-/* Start (run) and stop the inferior process, for GDB.
- Copyright 1986, 1987, 1988, 1989, 1991, 1992 Free Software Foundation, Inc.
+/* Target-struct-independent code to start (run) and stop an inferior process.
+ Copyright 1986-1989, 1991-1999 Free Software Foundation, Inc.
-This file is part of GDB.
+ This file is part of GDB.
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
-/* Notes on the algorithm used in wait_for_inferior to determine if we
- just did a subroutine call when stepping. We have the following
- information at that point:
+#include "defs.h"
+#include "gdb_string.h"
+#include <ctype.h>
+#include "symtab.h"
+#include "frame.h"
+#include "inferior.h"
+#include "breakpoint.h"
+#include "wait.h"
+#include "gdbcore.h"
+#include "gdbcmd.h"
+#include "target.h"
+#include "gdbthread.h"
+#include "annotate.h"
+#include "symfile.h" /* for overlay functions */
+#include "top.h"
+#include <signal.h>
+#include "event-loop.h"
+#include "event-top.h"
+#include "remote.h" /* For cleanup_sigint_signal_handler. */
- Current and previous (just before this step) pc.
- Current and previous sp.
- Current and previous start of current function.
+/* Prototypes for local functions */
- If the starts of the functions don't match, then
+static void signals_info (char *, int);
- a) We did a subroutine call.
+static void handle_command (char *, int);
- In this case, the pc will be at the beginning of a function.
+static void sig_print_info (enum target_signal);
- b) We did a subroutine return.
+static void sig_print_header (void);
- Otherwise.
+static void resume_cleanups (int);
- c) We did a longjmp.
+static int hook_stop_stub (void *);
- If we did a longjump, we were doing "nexti", since a next would
- have attempted to skip over the assembly language routine in which
- the longjmp is coded and would have simply been the equivalent of a
- continue. I consider this ok behaivior. We'd like one of two
- things to happen if we are doing a nexti through the longjmp()
- routine: 1) It behaves as a stepi, or 2) It acts like a continue as
- above. Given that this is a special case, and that anybody who
- thinks that the concept of sub calls is meaningful in the context
- of a longjmp, I'll take either one. Let's see what happens.
+static void delete_breakpoint_current_contents (void *);
- Acts like a subroutine return. I can handle that with no problem
- at all.
+static void set_follow_fork_mode_command (char *arg, int from_tty,
+ struct cmd_list_element * c);
- -->So: If the current and previous beginnings of the current
- function don't match, *and* the pc is at the start of a function,
- we've done a subroutine call. If the pc is not at the start of a
- function, we *didn't* do a subroutine call.
+static void complete_execution (void);
- -->If the beginnings of the current and previous function do match,
- either:
+static struct inferior_status *xmalloc_inferior_status (void);
- a) We just did a recursive call.
+static void free_inferior_status (struct inferior_status *);
- In this case, we would be at the very beginning of a
- function and 1) it will have a prologue (don't jump to
- before prologue, or 2) (we assume here that it doesn't have
- a prologue) there will have been a change in the stack
- pointer over the last instruction. (Ie. it's got to put
- the saved pc somewhere. The stack is the usual place. In
- a recursive call a register is only an option if there's a
- prologue to do something with it. This is even true on
- register window machines; the prologue sets up the new
- window. It might not be true on a register window machine
- where the call instruction moved the register window
- itself. Hmmm. One would hope that the stack pointer would
- also change. If it doesn't, somebody send me a note, and
- I'll work out a more general theory.
- bug-gdb@prep.ai.mit.edu). This is true (albeit slipperly
- so) on all machines I'm aware of:
+static int restore_selected_frame (void *);
- m68k: Call changes stack pointer. Regular jumps don't.
+static void build_infrun (void);
- sparc: Recursive calls must have frames and therefor,
- prologues.
+static void follow_inferior_fork (int parent_pid, int child_pid,
+ int has_forked, int has_vforked);
- vax: All calls have frames and hence change the
- stack pointer.
+static void follow_fork (int parent_pid, int child_pid);
- b) We did a return from a recursive call. I don't see that we
- have either the ability or the need to distinguish this
- from an ordinary jump. The stack frame will be printed
- when and if the frame pointer changes; if we are in a
- function without a frame pointer, it's the users own
- lookout.
+static void follow_vfork (int parent_pid, int child_pid);
- c) We did a jump within a function. We assume that this is
- true if we didn't do a recursive call.
+static void set_schedlock_func (char *args, int from_tty,
+ struct cmd_list_element * c);
- d) We are in no-man's land ("I see no symbols here"). We
- don't worry about this; it will make calls look like simple
- jumps (and the stack frames will be printed when the frame
- pointer moves), which is a reasonably non-violent response.
-*/
+static int is_internal_shlib_eventpoint (struct breakpoint * ep);
-#include "defs.h"
-#include <string.h>
-#include "symtab.h"
-#include "frame.h"
-#include "inferior.h"
-#include "breakpoint.h"
-#include "wait.h"
-#include "gdbcore.h"
-#include "command.h"
-#include "terminal.h" /* For #ifdef TIOCGPGRP and new_tty */
-#include "target.h"
+static int stopped_for_internal_shlib_event (bpstat bs);
-#include <signal.h>
+struct execution_control_state;
-/* unistd.h is needed to #define X_OK */
-#ifdef USG
-#include <unistd.h>
-#else
-#include <sys/file.h>
-#endif
+static int currently_stepping (struct execution_control_state *ecs);
-#ifdef SET_STACK_LIMIT_HUGE
-#include <sys/time.h>
-#include <sys/resource.h>
+static void xdb_handle_command (char *args, int from_tty);
-extern int original_stack_limit;
-#endif /* SET_STACK_LIMIT_HUGE */
+void _initialize_infrun (void);
-/* Prototypes for local functions */
+int inferior_ignoring_startup_exec_events = 0;
+int inferior_ignoring_leading_exec_events = 0;
-static void
-signals_info PARAMS ((char *, int));
+/* In asynchronous mode, but simulating synchronous execution. */
-static void
-handle_command PARAMS ((char *, int));
+int sync_execution = 0;
-static void
-sig_print_info PARAMS ((int));
+/* wait_for_inferior and normal_stop use this to notify the user
+ when the inferior stopped in a different thread than it had been
+ running in. */
-static void
-sig_print_header PARAMS ((void));
+static int switched_from_inferior_pid;
-static void
-remove_step_breakpoint PARAMS ((void));
+/* This will be true for configurations that may actually report an
+ inferior pid different from the original. At present this is only
+ true for HP-UX native. */
-static void
-insert_step_breakpoint PARAMS ((void));
+#ifndef MAY_SWITCH_FROM_INFERIOR_PID
+#define MAY_SWITCH_FROM_INFERIOR_PID (0)
+#endif
-static void
-resume PARAMS ((int, int));
+static int may_switch_from_inferior_pid = MAY_SWITCH_FROM_INFERIOR_PID;
-static void
-resume_cleanups PARAMS ((int));
+/* This is true for configurations that may follow through execl() and
+ similar functions. At present this is only true for HP-UX native. */
+
+#ifndef MAY_FOLLOW_EXEC
+#define MAY_FOLLOW_EXEC (0)
+#endif
+
+static int may_follow_exec = MAY_FOLLOW_EXEC;
-extern char **environ;
+/* resume and wait_for_inferior use this to ensure that when
+ stepping over a hit breakpoint in a threaded application
+ only the thread that hit the breakpoint is stepped and the
+ other threads don't continue. This prevents having another
+ thread run past the breakpoint while it is temporarily
+ removed.
-extern struct target_ops child_ops; /* In inftarg.c */
+ This is not thread-specific, so it isn't saved as part of
+ the infrun state.
-/* Sigtramp is a routine that the kernel calls (which then calls the
- signal handler). On most machines it is a library routine that
- is linked into the executable.
+ Versions of gdb which don't use the "step == this thread steps
+ and others continue" model but instead use the "step == this
+ thread steps and others wait" shouldn't do this. */
- This macro, given a program counter value and the name of the
- function in which that PC resides (which can be null if the
- name is not known), returns nonzero if the PC and name show
- that we are in sigtramp.
+static int thread_step_needed = 0;
- On most machines just see if the name is sigtramp (and if we have
- no name, assume we are not in sigtramp). */
-#if !defined (IN_SIGTRAMP)
-#define IN_SIGTRAMP(pc, name) \
- (name && !strcmp ("_sigtramp", name))
+/* This is true if thread_step_needed should actually be used. At
+ present this is only true for HP-UX native. */
+
+#ifndef USE_THREAD_STEP_NEEDED
+#define USE_THREAD_STEP_NEEDED (0)
#endif
+static int use_thread_step_needed = USE_THREAD_STEP_NEEDED;
+
/* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
program. It needs to examine the jmp_buf argument and extract the PC
from it. The return value is non-zero on success, zero otherwise. */
+
#ifndef GET_LONGJMP_TARGET
#define GET_LONGJMP_TARGET(PC_ADDR) 0
#endif
/* Some machines have trampoline code that sits between function callers
and the actual functions themselves. If this machine doesn't have
such things, disable their processing. */
+
#ifndef SKIP_TRAMPOLINE_CODE
#define SKIP_TRAMPOLINE_CODE(pc) 0
#endif
+/* Dynamic function trampolines are similar to solib trampolines in that they
+ are between the caller and the callee. The difference is that when you
+ enter a dynamic trampoline, you can't determine the callee's address. Some
+ (usually complex) code needs to run in the dynamic trampoline to figure out
+ the callee's address. This macro is usually called twice. First, when we
+ enter the trampoline (looks like a normal function call at that point). It
+ should return the PC of a point within the trampoline where the callee's
+ address is known. Second, when we hit the breakpoint, this routine returns
+ the callee's address. At that point, things proceed as per a step resume
+ breakpoint. */
+
+#ifndef DYNAMIC_TRAMPOLINE_NEXTPC
+#define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
+#endif
+
+/* If the program uses ELF-style shared libraries, then calls to
+ functions in shared libraries go through stubs, which live in a
+ table called the PLT (Procedure Linkage Table). The first time the
+ function is called, the stub sends control to the dynamic linker,
+ which looks up the function's real address, patches the stub so
+ that future calls will go directly to the function, and then passes
+ control to the function.
+
+ If we are stepping at the source level, we don't want to see any of
+ this --- we just want to skip over the stub and the dynamic linker.
+ The simple approach is to single-step until control leaves the
+ dynamic linker.
+
+ However, on some systems (e.g., Red Hat Linux 5.2) the dynamic
+ linker calls functions in the shared C library, so you can't tell
+ from the PC alone whether the dynamic linker is still running. In
+ this case, we use a step-resume breakpoint to get us past the
+ dynamic linker, as if we were using "next" to step over a function
+ call.
+
+ IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
+ linker code or not. Normally, this means we single-step. However,
+ if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
+ address where we can place a step-resume breakpoint to get past the
+ linker's symbol resolution function.
+
+ IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
+ pretty portable way, by comparing the PC against the address ranges
+ of the dynamic linker's sections.
+
+ SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
+ it depends on internal details of the dynamic linker. It's usually
+ not too hard to figure out where to put a breakpoint, but it
+ certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
+ sanity checking. If it can't figure things out, returning zero and
+ getting the (possibly confusing) stepping behavior is better than
+ signalling an error, which will obscure the change in the
+ inferior's state. */
+
+#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
+#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
+#endif
+
+#ifndef SKIP_SOLIB_RESOLVER
+#define SKIP_SOLIB_RESOLVER(pc) 0
+#endif
+
/* For SVR4 shared libraries, each call goes through a small piece of
- trampoline code in the ".init" section. IN_SOLIB_TRAMPOLINE evaluates
+ trampoline code in the ".plt" section. IN_SOLIB_CALL_TRAMPOLINE evaluates
to nonzero if we are current stopped in one of these. */
-#ifndef IN_SOLIB_TRAMPOLINE
-#define IN_SOLIB_TRAMPOLINE(pc,name) 0
+
+#ifndef IN_SOLIB_CALL_TRAMPOLINE
+#define IN_SOLIB_CALL_TRAMPOLINE(pc,name) 0
+#endif
+
+/* In some shared library schemes, the return path from a shared library
+ call may need to go through a trampoline too. */
+
+#ifndef IN_SOLIB_RETURN_TRAMPOLINE
+#define IN_SOLIB_RETURN_TRAMPOLINE(pc,name) 0
#endif
-/* Notify other parts of gdb that might care that signal handling may
- have changed for one or more signals. */
-#ifndef NOTICE_SIGNAL_HANDLING_CHANGE
-#define NOTICE_SIGNAL_HANDLING_CHANGE /* No actions */
+/* This function returns TRUE if pc is the address of an instruction
+ that lies within the dynamic linker (such as the event hook, or the
+ dld itself).
+
+ This function must be used only when a dynamic linker event has
+ been caught, and the inferior is being stepped out of the hook, or
+ undefined results are guaranteed. */
+
+#ifndef SOLIB_IN_DYNAMIC_LINKER
+#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
#endif
-#ifdef TDESC
-#include "tdesc.h"
-int safe_to_init_tdesc_context = 0;
-extern dc_dcontext_t current_context;
+/* On MIPS16, a function that returns a floating point value may call
+ a library helper function to copy the return value to a floating point
+ register. The IGNORE_HELPER_CALL macro returns non-zero if we
+ should ignore (i.e. step over) this function call. */
+#ifndef IGNORE_HELPER_CALL
+#define IGNORE_HELPER_CALL(pc) 0
#endif
-/* Tables of how to react to signals; the user sets them. */
+/* On some systems, the PC may be left pointing at an instruction that won't
+ actually be executed. This is usually indicated by a bit in the PSW. If
+ we find ourselves in such a state, then we step the target beyond the
+ nullified instruction before returning control to the user so as to avoid
+ confusion. */
-static char *signal_stop;
-static char *signal_print;
-static char *signal_program;
+#ifndef INSTRUCTION_NULLIFIED
+#define INSTRUCTION_NULLIFIED 0
+#endif
-/* Nonzero if breakpoints are now inserted in the inferior. */
-/* Nonstatic for initialization during xxx_create_inferior. FIXME. */
+/* We can't step off a permanent breakpoint in the ordinary way, because we
+ can't remove it. Instead, we have to advance the PC to the next
+ instruction. This macro should expand to a pointer to a function that
+ does that, or zero if we have no such function. If we don't have a
+ definition for it, we have to report an error. */
+#ifndef SKIP_PERMANENT_BREAKPOINT
+#define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
+static void
+default_skip_permanent_breakpoint ()
+{
+ error_begin ();
+ fprintf_filtered (gdb_stderr, "\
+The program is stopped at a permanent breakpoint, but GDB does not know\n\
+how to step past a permanent breakpoint on this architecture. Try using\n\
+a command like `return' or `jump' to continue execution.\n");
+ return_to_top_level (RETURN_ERROR);
+}
+#endif
+
-/*static*/ int breakpoints_inserted;
+/* Convert the #defines into values. This is temporary until wfi control
+ flow is completely sorted out. */
-/* Function inferior was in as of last step command. */
+#ifndef HAVE_STEPPABLE_WATCHPOINT
+#define HAVE_STEPPABLE_WATCHPOINT 0
+#else
+#undef HAVE_STEPPABLE_WATCHPOINT
+#define HAVE_STEPPABLE_WATCHPOINT 1
+#endif
+
+#ifndef HAVE_NONSTEPPABLE_WATCHPOINT
+#define HAVE_NONSTEPPABLE_WATCHPOINT 0
+#else
+#undef HAVE_NONSTEPPABLE_WATCHPOINT
+#define HAVE_NONSTEPPABLE_WATCHPOINT 1
+#endif
+
+#ifndef HAVE_CONTINUABLE_WATCHPOINT
+#define HAVE_CONTINUABLE_WATCHPOINT 0
+#else
+#undef HAVE_CONTINUABLE_WATCHPOINT
+#define HAVE_CONTINUABLE_WATCHPOINT 1
+#endif
+
+/* Tables of how to react to signals; the user sets them. */
+
+static unsigned char *signal_stop;
+static unsigned char *signal_print;
+static unsigned char *signal_program;
+
+#define SET_SIGS(nsigs,sigs,flags) \
+ do { \
+ int signum = (nsigs); \
+ while (signum-- > 0) \
+ if ((sigs)[signum]) \
+ (flags)[signum] = 1; \
+ } while (0)
+
+#define UNSET_SIGS(nsigs,sigs,flags) \
+ do { \
+ int signum = (nsigs); \
+ while (signum-- > 0) \
+ if ((sigs)[signum]) \
+ (flags)[signum] = 0; \
+ } while (0)
-static struct symbol *step_start_function;
-/* Nonzero => address for special breakpoint for resuming stepping. */
+/* Command list pointer for the "stop" placeholder. */
-static CORE_ADDR step_resume_break_address;
+static struct cmd_list_element *stop_command;
-/* Pointer to orig contents of the byte where the special breakpoint is. */
+/* Nonzero if breakpoints are now inserted in the inferior. */
-static char step_resume_break_shadow[BREAKPOINT_MAX];
+static int breakpoints_inserted;
-/* Nonzero means the special breakpoint is a duplicate
- so it has not itself been inserted. */
+/* Function inferior was in as of last step command. */
-static int step_resume_break_duplicate;
+static struct symbol *step_start_function;
/* Nonzero if we are expecting a trace trap and should proceed from it. */
static int trap_expected;
+#ifdef SOLIB_ADD
+/* Nonzero if we want to give control to the user when we're notified
+ of shared library events by the dynamic linker. */
+static int stop_on_solib_events;
+#endif
+
+#ifdef HP_OS_BUG
/* Nonzero if the next time we try to continue the inferior, it will
step one instruction and generate a spurious trace trap.
This is used to compensate for a bug in HP-UX. */
static int trap_expected_after_continue;
+#endif
/* Nonzero means expecting a trace trap
and should stop the inferior and return silently when it happens. */
int stop_soon_quietly;
-/* Nonzero if pc has been changed by the debugger
- since the inferior stopped. */
-
-int pc_changed;
-
/* Nonzero if proceed is being used for a "finish" command or a similar
situation when stop_registers should be saved. */
Thus this contains the return value from the called function (assuming
values are returned in a register). */
-char stop_registers[REGISTER_BYTES];
+char *stop_registers;
/* Nonzero if program stopped due to error trying to insert breakpoints. */
static int stop_print_frame;
-#ifdef NO_SINGLE_STEP
-extern int one_stepped; /* From machine dependent code */
-extern void single_step (); /* Same. */
-#endif /* NO_SINGLE_STEP */
+static struct breakpoint *step_resume_breakpoint = NULL;
+static struct breakpoint *through_sigtramp_breakpoint = NULL;
+
+/* On some platforms (e.g., HP-UX), hardware watchpoints have bad
+ interactions with an inferior that is running a kernel function
+ (aka, a system call or "syscall"). wait_for_inferior therefore
+ may have a need to know when the inferior is in a syscall. This
+ is a count of the number of inferior threads which are known to
+ currently be running in a syscall. */
+static int number_of_threads_in_syscalls;
+
+/* This is used to remember when a fork, vfork or exec event
+ was caught by a catchpoint, and thus the event is to be
+ followed at the next resume of the inferior, and not
+ immediately. */
+static struct
+ {
+ enum target_waitkind kind;
+ struct
+ {
+ int parent_pid;
+ int saw_parent_fork;
+ int child_pid;
+ int saw_child_fork;
+ int saw_child_exec;
+ }
+ fork_event;
+ char *execd_pathname;
+ }
+pending_follow;
+
+/* Some platforms don't allow us to do anything meaningful with a
+ vforked child until it has exec'd. Vforked processes on such
+ platforms can only be followed after they've exec'd.
+
+ When this is set to 0, a vfork can be immediately followed,
+ and an exec can be followed merely as an exec. When this is
+ set to 1, a vfork event has been seen, but cannot be followed
+ until the exec is seen.
+
+ (In the latter case, inferior_pid is still the parent of the
+ vfork, and pending_follow.fork_event.child_pid is the child. The
+ appropriate process is followed, according to the setting of
+ follow-fork-mode.) */
+static int follow_vfork_when_exec;
+
+static char *follow_fork_mode_kind_names[] =
+{
+/* ??rehrauer: The "both" option is broken, by what may be a 10.20
+ kernel problem. It's also not terribly useful without a GUI to
+ help the user drive two debuggers. So for now, I'm disabling
+ the "both" option.
+ "parent", "child", "both", "ask" };
+ */
+ "parent", "child", "ask"};
+
+static char *follow_fork_mode_string = NULL;
+\f
+
+static void
+follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
+ int has_vforked)
+{
+ int followed_parent = 0;
+ int followed_child = 0;
+
+ /* Which process did the user want us to follow? */
+ char *follow_mode =
+ savestring (follow_fork_mode_string, strlen (follow_fork_mode_string));
+
+ /* Or, did the user not know, and want us to ask? */
+ if (STREQ (follow_fork_mode_string, "ask"))
+ {
+ char requested_mode[100];
+
+ free (follow_mode);
+ error ("\"ask\" mode NYI");
+ follow_mode = savestring (requested_mode, strlen (requested_mode));
+ }
+
+ /* If we're to be following the parent, then detach from child_pid.
+ We're already following the parent, so need do nothing explicit
+ for it. */
+ if (STREQ (follow_mode, "parent"))
+ {
+ followed_parent = 1;
+
+ /* We're already attached to the parent, by default. */
+
+ /* Before detaching from the child, remove all breakpoints from
+ it. (This won't actually modify the breakpoint list, but will
+ physically remove the breakpoints from the child.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ detach_breakpoints (child_pid);
+#ifdef SOLIB_REMOVE_INFERIOR_HOOK
+ SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
+#endif
+ }
+
+ /* Detach from the child. */
+ dont_repeat ();
+
+ target_require_detach (child_pid, "", 1);
+ }
+
+ /* If we're to be following the child, then attach to it, detach
+ from inferior_pid, and set inferior_pid to child_pid. */
+ else if (STREQ (follow_mode, "child"))
+ {
+ char child_pid_spelling[100]; /* Arbitrary length. */
+
+ followed_child = 1;
+
+ /* Before detaching from the parent, detach all breakpoints from
+ the child. But only if we're forking, or if we follow vforks
+ as soon as they happen. (If we're following vforks only when
+ the child has exec'd, then it's very wrong to try to write
+ back the "shadow contents" of inserted breakpoints now -- they
+ belong to the child's pre-exec'd a.out.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ detach_breakpoints (child_pid);
+ }
+
+ /* Before detaching from the parent, remove all breakpoints from it. */
+ remove_breakpoints ();
+
+ /* Also reset the solib inferior hook from the parent. */
+#ifdef SOLIB_REMOVE_INFERIOR_HOOK
+ SOLIB_REMOVE_INFERIOR_HOOK (inferior_pid);
+#endif
+
+ /* Detach from the parent. */
+ dont_repeat ();
+ target_detach (NULL, 1);
+
+ /* Attach to the child. */
+ inferior_pid = child_pid;
+ sprintf (child_pid_spelling, "%d", child_pid);
+ dont_repeat ();
+
+ target_require_attach (child_pid_spelling, 1);
+
+ /* Was there a step_resume breakpoint? (There was if the user
+ did a "next" at the fork() call.) If so, explicitly reset its
+ thread number.
+
+ step_resumes are a form of bp that are made to be per-thread.
+ Since we created the step_resume bp when the parent process
+ was being debugged, and now are switching to the child process,
+ from the breakpoint package's viewpoint, that's a switch of
+ "threads". We must update the bp's notion of which thread
+ it is for, or it'll be ignored when it triggers... */
+ if (step_resume_breakpoint &&
+ (!has_vforked || !follow_vfork_when_exec))
+ breakpoint_re_set_thread (step_resume_breakpoint);
+
+ /* Reinsert all breakpoints in the child. (The user may've set
+ breakpoints after catching the fork, in which case those
+ actually didn't get set in the child, but only in the parent.) */
+ if (!has_vforked || !follow_vfork_when_exec)
+ {
+ breakpoint_re_set ();
+ insert_breakpoints ();
+ }
+ }
+
+ /* If we're to be following both parent and child, then fork ourselves,
+ and attach the debugger clone to the child. */
+ else if (STREQ (follow_mode, "both"))
+ {
+ char pid_suffix[100]; /* Arbitrary length. */
+
+ /* Clone ourselves to follow the child. This is the end of our
+ involvement with child_pid; our clone will take it from here... */
+ dont_repeat ();
+ target_clone_and_follow_inferior (child_pid, &followed_child);
+ followed_parent = !followed_child;
+
+ /* We continue to follow the parent. To help distinguish the two
+ debuggers, though, both we and our clone will reset our prompts. */
+ sprintf (pid_suffix, "[%d] ", inferior_pid);
+ set_prompt (strcat (get_prompt (), pid_suffix));
+ }
+
+ /* The parent and child of a vfork share the same address space.
+ Also, on some targets the order in which vfork and exec events
+ are received for parent in child requires some delicate handling
+ of the events.
+
+ For instance, on ptrace-based HPUX we receive the child's vfork
+ event first, at which time the parent has been suspended by the
+ OS and is essentially untouchable until the child's exit or second
+ exec event arrives. At that time, the parent's vfork event is
+ delivered to us, and that's when we see and decide how to follow
+ the vfork. But to get to that point, we must continue the child
+ until it execs or exits. To do that smoothly, all breakpoints
+ must be removed from the child, in case there are any set between
+ the vfork() and exec() calls. But removing them from the child
+ also removes them from the parent, due to the shared-address-space
+ nature of a vfork'd parent and child. On HPUX, therefore, we must
+ take care to restore the bp's to the parent before we continue it.
+ Else, it's likely that we may not stop in the expected place. (The
+ worst scenario is when the user tries to step over a vfork() call;
+ the step-resume bp must be restored for the step to properly stop
+ in the parent after the call completes!)
+
+ Sequence of events, as reported to gdb from HPUX:
+
+ Parent Child Action for gdb to take
+ -------------------------------------------------------
+ 1 VFORK Continue child
+ 2 EXEC
+ 3 EXEC or EXIT
+ 4 VFORK */
+ if (has_vforked)
+ {
+ target_post_follow_vfork (parent_pid,
+ followed_parent,
+ child_pid,
+ followed_child);
+ }
+
+ pending_follow.fork_event.saw_parent_fork = 0;
+ pending_follow.fork_event.saw_child_fork = 0;
+
+ free (follow_mode);
+}
+
+static void
+follow_fork (int parent_pid, int child_pid)
+{
+ follow_inferior_fork (parent_pid, child_pid, 1, 0);
+}
+
+
+/* Forward declaration. */
+static void follow_exec (int, char *);
+
+static void
+follow_vfork (int parent_pid, int child_pid)
+{
+ follow_inferior_fork (parent_pid, child_pid, 0, 1);
+
+ /* Did we follow the child? Had it exec'd before we saw the parent vfork? */
+ if (pending_follow.fork_event.saw_child_exec && (inferior_pid == child_pid))
+ {
+ pending_follow.fork_event.saw_child_exec = 0;
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_exec (inferior_pid, pending_follow.execd_pathname);
+ free (pending_follow.execd_pathname);
+ }
+}
+
+static void
+follow_exec (int pid, char *execd_pathname)
+{
+ int saved_pid = pid;
+ struct target_ops *tgt;
+
+ if (!may_follow_exec)
+ return;
+
+ /* Did this exec() follow a vfork()? If so, we must follow the
+ vfork now too. Do it before following the exec. */
+ if (follow_vfork_when_exec &&
+ (pending_follow.kind == TARGET_WAITKIND_VFORKED))
+ {
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
+ follow_vfork_when_exec = 0;
+ saved_pid = inferior_pid;
+
+ /* Did we follow the parent? If so, we're done. If we followed
+ the child then we must also follow its exec(). */
+ if (inferior_pid == pending_follow.fork_event.parent_pid)
+ return;
+ }
+
+ /* This is an exec event that we actually wish to pay attention to.
+ Refresh our symbol table to the newly exec'd program, remove any
+ momentary bp's, etc.
+
+ If there are breakpoints, they aren't really inserted now,
+ since the exec() transformed our inferior into a fresh set
+ of instructions.
+
+ We want to preserve symbolic breakpoints on the list, since
+ we have hopes that they can be reset after the new a.out's
+ symbol table is read.
+
+ However, any "raw" breakpoints must be removed from the list
+ (e.g., the solib bp's), since their address is probably invalid
+ now.
+
+ And, we DON'T want to call delete_breakpoints() here, since
+ that may write the bp's "shadow contents" (the instruction
+ value that was overwritten witha TRAP instruction). Since
+ we now have a new a.out, those shadow contents aren't valid. */
+ update_breakpoints_after_exec ();
+
+ /* If there was one, it's gone now. We cannot truly step-to-next
+ statement through an exec(). */
+ step_resume_breakpoint = NULL;
+ step_range_start = 0;
+ step_range_end = 0;
+
+ /* If there was one, it's gone now. */
+ through_sigtramp_breakpoint = NULL;
+
+ /* What is this a.out's name? */
+ printf_unfiltered ("Executing new program: %s\n", execd_pathname);
+
+ /* We've followed the inferior through an exec. Therefore, the
+ inferior has essentially been killed & reborn. */
+
+ /* First collect the run target in effect. */
+ tgt = find_run_target ();
+ /* If we can't find one, things are in a very strange state... */
+ if (tgt == NULL)
+ error ("Could find run target to save before following exec");
+
+ gdb_flush (gdb_stdout);
+ target_mourn_inferior ();
+ inferior_pid = saved_pid; /* Because mourn_inferior resets inferior_pid. */
+ push_target (tgt);
+
+ /* That a.out is now the one to use. */
+ exec_file_attach (execd_pathname, 0);
+
+ /* And also is where symbols can be found. */
+ symbol_file_command (execd_pathname, 0);
+
+ /* Reset the shared library package. This ensures that we get
+ a shlib event when the child reaches "_start", at which point
+ the dld will have had a chance to initialize the child. */
+#if defined(SOLIB_RESTART)
+ SOLIB_RESTART ();
+#endif
+#ifdef SOLIB_CREATE_INFERIOR_HOOK
+ SOLIB_CREATE_INFERIOR_HOOK (inferior_pid);
+#endif
+
+ /* Reinsert all breakpoints. (Those which were symbolic have
+ been reset to the proper address in the new a.out, thanks
+ to symbol_file_command...) */
+ insert_breakpoints ();
+ /* The next resume of this inferior should bring it to the shlib
+ startup breakpoints. (If the user had also set bp's on
+ "main" from the old (parent) process, then they'll auto-
+ matically get reset there in the new process.) */
+}
+
+/* Non-zero if we just simulating a single-step. This is needed
+ because we cannot remove the breakpoints in the inferior process
+ until after the `wait' in `wait_for_inferior'. */
+static int singlestep_breakpoints_inserted_p = 0;
\f
+
/* Things to clean up if we QUIT out of resume (). */
/* ARGSUSED */
static void
-resume_cleanups (arg)
- int arg;
+resume_cleanups (int arg)
{
normal_stop ();
}
+static char schedlock_off[] = "off";
+static char schedlock_on[] = "on";
+static char schedlock_step[] = "step";
+static char *scheduler_mode = schedlock_off;
+static char *scheduler_enums[] =
+{schedlock_off, schedlock_on, schedlock_step};
+
+static void
+set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
+{
+ if (c->type == set_cmd)
+ if (!target_can_lock_scheduler)
+ {
+ scheduler_mode = schedlock_off;
+ error ("Target '%s' cannot support this command.",
+ target_shortname);
+ }
+}
+
+
+
+
/* Resume the inferior, but allow a QUIT. This is useful if the user
wants to interrupt some lengthy single-stepping operation
(for child processes, the SIGINT goes to the inferior, and so
STEP nonzero if we should step (zero to continue instead).
SIG is the signal to give the inferior (zero for none). */
-static void
-resume (step, sig)
- int step;
- int sig;
+void
+resume (int step, enum target_signal sig)
{
- struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
+ int should_resume = 1;
+ struct cleanup *old_cleanups = make_cleanup ((make_cleanup_func)
+ resume_cleanups, 0);
QUIT;
-#ifdef NO_SINGLE_STEP
- if (step) {
- single_step(sig); /* Do it the hard way, w/temp breakpoints */
- step = 0; /* ...and don't ask hardware to do it. */
- }
+#ifdef CANNOT_STEP_BREAKPOINT
+ /* Most targets can step a breakpoint instruction, thus executing it
+ normally. But if this one cannot, just continue and we will hit
+ it anyway. */
+ if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
+ step = 0;
#endif
+ /* Normally, by the time we reach `resume', the breakpoints are either
+ removed or inserted, as appropriate. The exception is if we're sitting
+ at a permanent breakpoint; we need to step over it, but permanent
+ breakpoints can't be removed. So we have to test for it here. */
+ if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
+ SKIP_PERMANENT_BREAKPOINT ();
+
+ if (SOFTWARE_SINGLE_STEP_P && step)
+ {
+ /* Do it the hard way, w/temp breakpoints */
+ SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
+ /* ...and don't ask hardware to do it. */
+ step = 0;
+ /* and do not pull these breakpoints until after a `wait' in
+ `wait_for_inferior' */
+ singlestep_breakpoints_inserted_p = 1;
+ }
+
/* Handle any optimized stores to the inferior NOW... */
#ifdef DO_DEFERRED_STORES
DO_DEFERRED_STORES;
#endif
- target_resume (step, sig);
+ /* If there were any forks/vforks/execs that were caught and are
+ now to be followed, then do so. */
+ switch (pending_follow.kind)
+ {
+ case (TARGET_WAITKIND_FORKED):
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_fork (inferior_pid, pending_follow.fork_event.child_pid);
+ break;
+
+ case (TARGET_WAITKIND_VFORKED):
+ {
+ int saw_child_exec = pending_follow.fork_event.saw_child_exec;
+
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ follow_vfork (inferior_pid, pending_follow.fork_event.child_pid);
+
+ /* Did we follow the child, but not yet see the child's exec event?
+ If so, then it actually ought to be waiting for us; we respond to
+ parent vfork events. We don't actually want to resume the child
+ in this situation; we want to just get its exec event. */
+ if (!saw_child_exec &&
+ (inferior_pid == pending_follow.fork_event.child_pid))
+ should_resume = 0;
+ }
+ break;
+
+ case (TARGET_WAITKIND_EXECD):
+ /* If we saw a vfork event but couldn't follow it until we saw
+ an exec, then now might be the time! */
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ /* follow_exec is called as soon as the exec event is seen. */
+ break;
+
+ default:
+ break;
+ }
+
+ /* Install inferior's terminal modes. */
+ target_terminal_inferior ();
+
+ if (should_resume)
+ {
+ if (use_thread_step_needed && thread_step_needed)
+ {
+ /* We stopped on a BPT instruction;
+ don't continue other threads and
+ just step this thread. */
+ thread_step_needed = 0;
+
+ if (!breakpoint_here_p (read_pc ()))
+ {
+ /* Breakpoint deleted: ok to do regular resume
+ where all the threads either step or continue. */
+ target_resume (-1, step, sig);
+ }
+ else
+ {
+ if (!step)
+ {
+ warning ("Internal error, changing continue to step.");
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ trap_expected = 1;
+ step = 1;
+ }
+
+ target_resume (inferior_pid, step, sig);
+ }
+ }
+ else
+ {
+ /* Vanilla resume. */
+
+ if ((scheduler_mode == schedlock_on) ||
+ (scheduler_mode == schedlock_step && step != 0))
+ target_resume (inferior_pid, step, sig);
+ else
+ target_resume (-1, step, sig);
+ }
+ }
+
discard_cleanups (old_cleanups);
}
-
\f
+
/* Clear out all variables saying what to do when inferior is continued.
First do this, then set the ones you want, then call `proceed'. */
void
-clear_proceed_status ()
+clear_proceed_status (void)
{
trap_expected = 0;
step_range_start = 0;
step_range_end = 0;
step_frame_address = 0;
step_over_calls = -1;
- step_resume_break_address = 0;
stop_after_trap = 0;
stop_soon_quietly = 0;
proceed_to_finish = 0;
ADDR is the address to resume at, or -1 for resume where stopped.
SIGGNAL is the signal to give it, or 0 for none,
- or -1 for act according to how it stopped.
+ or -1 for act according to how it stopped.
STEP is nonzero if should trap after one instruction.
- -1 means return after that and print nothing.
- You should probably set various step_... variables
- before calling here, if you are stepping.
+ -1 means return after that and print nothing.
+ You should probably set various step_... variables
+ before calling here, if you are stepping.
You should call clear_proceed_status before calling proceed. */
void
-proceed (addr, siggnal, step)
- CORE_ADDR addr;
- int siggnal;
- int step;
+proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
{
int oneproc = 0;
if (step < 0)
stop_after_trap = 1;
- if (addr == (CORE_ADDR)-1)
+ if (addr == (CORE_ADDR) - 1)
{
/* If there is a breakpoint at the address we will resume at,
- step one instruction before inserting breakpoints
- so that we do not stop right away. */
+ step one instruction before inserting breakpoints
+ so that we do not stop right away (and report a second
+ hit at this breakpoint). */
- if (!pc_changed && breakpoint_here_p (read_pc ()))
+ if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
+ oneproc = 1;
+
+#ifndef STEP_SKIPS_DELAY
+#define STEP_SKIPS_DELAY(pc) (0)
+#define STEP_SKIPS_DELAY_P (0)
+#endif
+ /* Check breakpoint_here_p first, because breakpoint_here_p is fast
+ (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
+ is slow (it needs to read memory from the target). */
+ if (STEP_SKIPS_DELAY_P
+ && breakpoint_here_p (read_pc () + 4)
+ && STEP_SKIPS_DELAY (read_pc ()))
oneproc = 1;
}
else
{
- write_register (PC_REGNUM, addr);
-#ifdef NPC_REGNUM
- write_register (NPC_REGNUM, addr + 4);
-#ifdef NNPC_REGNUM
- write_register (NNPC_REGNUM, addr + 8);
-#endif
-#endif
+ write_pc (addr);
+
+ /* New address; we don't need to single-step a thread
+ over a breakpoint we just hit, 'cause we aren't
+ continuing from there.
+
+ It's not worth worrying about the case where a user
+ asks for a "jump" at the current PC--if they get the
+ hiccup of re-hiting a hit breakpoint, what else do
+ they expect? */
+ thread_step_needed = 0;
+ }
+
+#ifdef PREPARE_TO_PROCEED
+ /* In a multi-threaded task we may select another thread
+ and then continue or step.
+
+ But if the old thread was stopped at a breakpoint, it
+ will immediately cause another breakpoint stop without
+ any execution (i.e. it will report a breakpoint hit
+ incorrectly). So we must step over it first.
+
+ PREPARE_TO_PROCEED checks the current thread against the thread
+ that reported the most recent event. If a step-over is required
+ it returns TRUE and sets the current thread to the old thread. */
+ if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
+ {
+ oneproc = 1;
+ thread_step_needed = 1;
}
+#endif /* PREPARE_TO_PROCEED */
+
+#ifdef HP_OS_BUG
if (trap_expected_after_continue)
{
/* If (step == 0), a trap will be automatically generated after
- the first instruction is executed. Force step one
- instruction to clear this condition. This should not occur
- if step is nonzero, but it is harmless in that case. */
+ the first instruction is executed. Force step one
+ instruction to clear this condition. This should not occur
+ if step is nonzero, but it is harmless in that case. */
oneproc = 1;
trap_expected_after_continue = 0;
}
+#endif /* HP_OS_BUG */
if (oneproc)
/* We will get a trace trap after one instruction.
error ("Cannot insert breakpoints.\n\
The same program may be running in another process.");
}
+
breakpoints_inserted = 1;
}
- /* Install inferior's terminal modes. */
- target_terminal_inferior ();
-
- if (siggnal >= 0)
+ if (siggnal != TARGET_SIGNAL_DEFAULT)
stop_signal = siggnal;
/* If this signal should not be seen by program,
give it zero. Used for debugging signals. */
- else if (stop_signal < NSIG && !signal_program[stop_signal])
- stop_signal= 0;
+ else if (!signal_program[stop_signal])
+ stop_signal = TARGET_SIGNAL_0;
+
+ annotate_starting ();
+
+ /* Make sure that output from GDB appears before output from the
+ inferior. */
+ gdb_flush (gdb_stdout);
/* Resume inferior. */
resume (oneproc || step || bpstat_should_step (), stop_signal);
/* Wait for it to stop (if not standalone)
and in any case decode why it stopped, and act accordingly. */
-
- wait_for_inferior ();
- normal_stop ();
+ /* Do this only if we are not using the event loop, or if the target
+ does not support asynchronous execution. */
+ if (!async_p || !target_has_async)
+ {
+ wait_for_inferior ();
+ normal_stop ();
+ }
}
/* Record the pc and sp of the program the last time it stopped.
to be preserved over calls to it and cleared when the inferior
is started. */
static CORE_ADDR prev_pc;
-static CORE_ADDR prev_sp;
static CORE_ADDR prev_func_start;
static char *prev_func_name;
-
\f
-/* Start an inferior Unix child process and sets inferior_pid to its pid.
- EXEC_FILE is the file to run.
- ALLARGS is a string containing the arguments to the program.
- ENV is the environment vector to pass. Errors reported with error(). */
-#ifndef SHELL_FILE
-#define SHELL_FILE "/bin/sh"
-#endif
+/* Start remote-debugging of a machine over a serial link. */
void
-child_create_inferior (exec_file, allargs, env)
- char *exec_file;
- char *allargs;
- char **env;
+start_remote (void)
{
- int pid;
- char *shell_command;
- char *shell_file;
- static char default_shell_file[] = SHELL_FILE;
- int len;
- int pending_execs;
- /* Set debug_fork then attach to the child while it sleeps, to debug. */
- static int debug_fork = 0;
- /* This is set to the result of setpgrp, which if vforked, will be visible
- to you in the parent process. It's only used by humans for debugging. */
- static int debug_setpgrp = 657473;
- char **save_our_env;
-
- /* The user might want tilde-expansion, and in general probably wants
- the program to behave the same way as if run from
- his/her favorite shell. So we let the shell run it for us.
- FIXME, this should probably search the local environment (as
- modified by the setenv command), not the env gdb inherited. */
- shell_file = getenv ("SHELL");
- if (shell_file == NULL)
- shell_file = default_shell_file;
-
- len = 5 + strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop*/ 10;
- /* If desired, concat something onto the front of ALLARGS.
- SHELL_COMMAND is the result. */
-#ifdef SHELL_COMMAND_CONCAT
- shell_command = (char *) alloca (strlen (SHELL_COMMAND_CONCAT) + len);
- strcpy (shell_command, SHELL_COMMAND_CONCAT);
-#else
- shell_command = (char *) alloca (len);
- shell_command[0] = '\0';
-#endif
- strcat (shell_command, "exec ");
- strcat (shell_command, exec_file);
- strcat (shell_command, " ");
- strcat (shell_command, allargs);
+ init_thread_list ();
+ init_wait_for_inferior ();
+ stop_soon_quietly = 1;
+ trap_expected = 0;
- /* exec is said to fail if the executable is open. */
- close_exec_file ();
+ /* Go on waiting only in case gdb is not started in async mode, or
+ in case the target doesn't support async execution. */
+ if (!async_p || !target_has_async)
+ {
+ wait_for_inferior ();
+ normal_stop ();
+ }
+ else
+ {
+ /* The 'tar rem' command should always look synchronous,
+ i.e. display the prompt only once it has connected and
+ started the target. */
+ sync_execution = 1;
+ push_prompt ("", "", "");
+ delete_file_handler (input_fd);
+ target_executing = 1;
+ }
+}
- /* Retain a copy of our environment variables, since the child will
- replace the value of environ and if we're vforked, we have to
- restore it. */
- save_our_env = environ;
+/* Initialize static vars when a new inferior begins. */
- /* Tell the terminal handling subsystem what tty we plan to run on;
- it will just record the information for later. */
+void
+init_wait_for_inferior (void)
+{
+ /* These are meaningless until the first time through wait_for_inferior. */
+ prev_pc = 0;
+ prev_func_start = 0;
+ prev_func_name = NULL;
- new_tty_prefork (inferior_io_terminal);
+#ifdef HP_OS_BUG
+ trap_expected_after_continue = 0;
+#endif
+ breakpoints_inserted = 0;
+ breakpoint_init_inferior (inf_starting);
- /* It is generally good practice to flush any possible pending stdio
- output prior to doing a fork, to avoid the possibility of both the
- parent and child flushing the same data after the fork. */
+ /* Don't confuse first call to proceed(). */
+ stop_signal = TARGET_SIGNAL_0;
- fflush (stdout);
- fflush (stderr);
+ /* The first resume is not following a fork/vfork/exec. */
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
+ pending_follow.fork_event.saw_parent_fork = 0;
+ pending_follow.fork_event.saw_child_fork = 0;
+ pending_follow.fork_event.saw_child_exec = 0;
-#if defined(USG) && !defined(HAVE_VFORK)
- pid = fork ();
-#else
- if (debug_fork)
- pid = fork ();
- else
- pid = vfork ();
-#endif
+ /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
+ number_of_threads_in_syscalls = 0;
- if (pid < 0)
- perror_with_name ("vfork");
+ clear_proceed_status ();
+}
- if (pid == 0)
+static void
+delete_breakpoint_current_contents (void *arg)
+{
+ struct breakpoint **breakpointp = (struct breakpoint **) arg;
+ if (*breakpointp != NULL)
{
- if (debug_fork)
- sleep (debug_fork);
+ delete_breakpoint (*breakpointp);
+ *breakpointp = NULL;
+ }
+}
+\f
+/* This enum encodes possible reasons for doing a target_wait, so that
+ wfi can call target_wait in one place. (Ultimately the call will be
+ moved out of the infinite loop entirely.) */
-#ifdef TIOCGPGRP
- /* Run inferior in a separate process group. */
-#ifdef NEED_POSIX_SETPGID
- debug_setpgrp = setpgid (0, 0);
-#else
-#if defined(USG) && !defined(SETPGRP_ARGS)
- debug_setpgrp = setpgrp ();
-#else
- debug_setpgrp = setpgrp (getpid (), getpid ());
-#endif /* USG */
-#endif /* NEED_POSIX_SETPGID */
- if (debug_setpgrp == -1)
- perror("setpgrp failed in child");
-#endif /* TIOCGPGRP */
-
-#ifdef SET_STACK_LIMIT_HUGE
- /* Reset the stack limit back to what it was. */
- {
- struct rlimit rlim;
+enum infwait_states
+{
+ infwait_normal_state,
+ infwait_thread_hop_state,
+ infwait_nullified_state,
+ infwait_nonstep_watch_state
+};
+
+/* This structure contains what used to be local variables in
+ wait_for_inferior. Probably many of them can return to being
+ locals in handle_inferior_event. */
+
+struct execution_control_state
+ {
+ struct target_waitstatus ws;
+ struct target_waitstatus *wp;
+ int another_trap;
+ int random_signal;
+ CORE_ADDR stop_func_start;
+ CORE_ADDR stop_func_end;
+ char *stop_func_name;
+ struct symtab_and_line sal;
+ int remove_breakpoints_on_following_step;
+ int current_line;
+ struct symtab *current_symtab;
+ int handling_longjmp; /* FIXME */
+ int pid;
+ int saved_inferior_pid;
+ int update_step_sp;
+ int stepping_through_solib_after_catch;
+ bpstat stepping_through_solib_catchpoints;
+ int enable_hw_watchpoints_after_wait;
+ int stepping_through_sigtramp;
+ int new_thread_event;
+ struct target_waitstatus tmpstatus;
+ enum infwait_states infwait_state;
+ int waiton_pid;
+ int wait_some_more;
+ };
+
+void init_execution_control_state (struct execution_control_state * ecs);
+
+void handle_inferior_event (struct execution_control_state * ecs);
+
+static void check_sigtramp2 (struct execution_control_state *ecs);
+static void step_into_function (struct execution_control_state *ecs);
+static void step_over_function (struct execution_control_state *ecs);
+static void stop_stepping (struct execution_control_state *ecs);
+static void prepare_to_wait (struct execution_control_state *ecs);
+static void keep_going (struct execution_control_state *ecs);
- getrlimit (RLIMIT_STACK, &rlim);
- rlim.rlim_cur = original_stack_limit;
- setrlimit (RLIMIT_STACK, &rlim);
- }
-#endif /* SET_STACK_LIMIT_HUGE */
+/* Wait for control to return from inferior to debugger.
+ If inferior gets a signal, we may decide to start it up again
+ instead of returning. That is why there is a loop in this function.
+ When this function actually returns it means the inferior
+ should be left stopped and GDB should read more commands. */
- /* Ask the tty subsystem to switch to the one we specified earlier
- (or to share the current terminal, if none was specified). */
+void
+wait_for_inferior (void)
+{
+ struct cleanup *old_cleanups;
+ struct execution_control_state ecss;
+ struct execution_control_state *ecs;
- new_tty ();
+ old_cleanups = make_cleanup (delete_breakpoint_current_contents,
+ &step_resume_breakpoint);
+ make_cleanup (delete_breakpoint_current_contents,
+ &through_sigtramp_breakpoint);
- /* Changing the signal handlers for the inferior after
- a vfork can also change them for the superior, so we don't mess
- with signals here. See comments in
- initialize_signals for how we get the right signal handlers
- for the inferior. */
+ /* wfi still stays in a loop, so it's OK just to take the address of
+ a local to get the ecs pointer. */
+ ecs = &ecss;
-#ifdef USE_PROC_FS
- proc_set_exec_trap (); /* Use SVR4 /proc interface */
-#else
- call_ptrace (0, 0, 0, 0); /* "Trace me, Dr. Memory!" */
-#endif
+ /* Fill in with reasonable starting values. */
+ init_execution_control_state (ecs);
- /* There is no execlpe call, so we have to set the environment
- for our child in the global variable. If we've vforked, this
- clobbers the parent, but environ is restored a few lines down
- in the parent. By the way, yes we do need to look down the
- path to find $SHELL. Rich Pixley says so, and I agree. */
- environ = env;
- execlp (shell_file, shell_file, "-c", shell_command, (char *)0);
-
- fprintf (stderr, "Cannot exec %s: %s.\n", shell_file,
- safe_strerror (errno));
- fflush (stderr);
- _exit (0177);
- }
+ thread_step_needed = 0;
- /* Restore our environment in case a vforked child clob'd it. */
- environ = save_our_env;
+ /* We'll update this if & when we switch to a new thread. */
+ if (may_switch_from_inferior_pid)
+ switched_from_inferior_pid = inferior_pid;
- /* Now that we have a child process, make it our target. */
- push_target (&child_ops);
+ overlay_cache_invalid = 1;
-#ifdef CREATE_INFERIOR_HOOK
- CREATE_INFERIOR_HOOK (pid);
-#endif
+ /* We have to invalidate the registers BEFORE calling target_wait
+ because they can be loaded from the target while in target_wait.
+ This makes remote debugging a bit more efficient for those
+ targets that provide critical registers as part of their normal
+ status mechanism. */
-/* The process was started by the fork that created it,
- but it will have stopped one instruction after execing the shell.
- Here we must get it up to actual execution of the real program. */
+ registers_changed ();
- inferior_pid = pid; /* Needed for wait_for_inferior stuff below */
+ while (1)
+ {
+ if (target_wait_hook)
+ ecs->pid = target_wait_hook (ecs->waiton_pid, ecs->wp);
+ else
+ ecs->pid = target_wait (ecs->waiton_pid, ecs->wp);
- clear_proceed_status ();
+ /* Now figure out what to do with the result of the result. */
+ handle_inferior_event (ecs);
- /* We will get a trace trap after one instruction.
- Continue it automatically. Eventually (after shell does an exec)
- it will get another trace trap. Then insert breakpoints and continue. */
+ if (!ecs->wait_some_more)
+ break;
+ }
+ do_cleanups (old_cleanups);
+}
-#ifdef START_INFERIOR_TRAPS_EXPECTED
- pending_execs = START_INFERIOR_TRAPS_EXPECTED;
-#else
- pending_execs = 2;
-#endif
+/* Asynchronous version of wait_for_inferior. It is called by the
+ event loop whenever a change of state is detected on the file
+ descriptor corresponding to the target. It can be called more than
+ once to complete a single execution command. In such cases we need
+ to keep the state in a global variable ASYNC_ECSS. If it is the
+ last time that this function is called for a single execution
+ command, then report to the user that the inferior has stopped, and
+ do the necessary cleanups. */
- init_wait_for_inferior ();
+struct execution_control_state async_ecss;
+struct execution_control_state *async_ecs;
- /* Set up the "saved terminal modes" of the inferior
- based on what modes we are starting it with. */
- target_terminal_init ();
+void
+fetch_inferior_event (client_data)
+ gdb_client_data client_data;
+{
+ static struct cleanup *old_cleanups;
- /* Install inferior's terminal modes. */
- target_terminal_inferior ();
+ async_ecs = &async_ecss;
- while (1)
+ if (!async_ecs->wait_some_more)
{
- stop_soon_quietly = 1; /* Make wait_for_inferior be quiet */
- wait_for_inferior ();
- if (stop_signal != SIGTRAP)
- {
- /* Let shell child handle its own signals in its own way */
- /* FIXME, what if child has exit()ed? Must exit loop somehow */
- resume (0, stop_signal);
- }
- else
- {
- /* We handle SIGTRAP, however; it means child did an exec. */
- if (0 == --pending_execs)
- break;
- resume (0, 0); /* Just make it go on */
- }
+ old_cleanups = make_exec_cleanup (delete_breakpoint_current_contents,
+ &step_resume_breakpoint);
+ make_exec_cleanup (delete_breakpoint_current_contents,
+ &through_sigtramp_breakpoint);
+
+ /* Fill in with reasonable starting values. */
+ init_execution_control_state (async_ecs);
+
+ thread_step_needed = 0;
+
+ /* We'll update this if & when we switch to a new thread. */
+ if (may_switch_from_inferior_pid)
+ switched_from_inferior_pid = inferior_pid;
+
+ overlay_cache_invalid = 1;
+
+ /* We have to invalidate the registers BEFORE calling target_wait
+ because they can be loaded from the target while in target_wait.
+ This makes remote debugging a bit more efficient for those
+ targets that provide critical registers as part of their normal
+ status mechanism. */
+
+ registers_changed ();
}
- stop_soon_quietly = 0;
- /* We are now in the child process of interest, having exec'd the
- correct program, and are poised at the first instruction of the
- new program. */
-#ifdef SOLIB_CREATE_INFERIOR_HOOK
- SOLIB_CREATE_INFERIOR_HOOK (pid);
-#endif
+ if (target_wait_hook)
+ async_ecs->pid = target_wait_hook (async_ecs->waiton_pid, async_ecs->wp);
+ else
+ async_ecs->pid = target_wait (async_ecs->waiton_pid, async_ecs->wp);
- /* Should this perhaps just be a "proceed" call? FIXME */
- insert_step_breakpoint ();
- breakpoints_failed = insert_breakpoints ();
- if (!breakpoints_failed)
+ /* Now figure out what to do with the result of the result. */
+ handle_inferior_event (async_ecs);
+
+ if (!async_ecs->wait_some_more)
{
- breakpoints_inserted = 1;
- target_terminal_inferior();
- /* Start the child program going on its first instruction, single-
- stepping if we need to. */
- resume (bpstat_should_step (), 0);
- wait_for_inferior ();
+ /* Do only the cleanups that have been added by this
+ function. Let the continuations for the commands do the rest,
+ if there are any. */
+ do_exec_cleanups (old_cleanups);
normal_stop ();
+ /* Is there anything left to do for the command issued to
+ complete? */
+ do_all_continuations ();
+ /* Reset things after target has stopped for the async commands. */
+ complete_execution ();
}
}
-/* Start remote-debugging of a machine over a serial link. */
+/* Prepare an execution control state for looping through a
+ wait_for_inferior-type loop. */
void
-start_remote ()
+init_execution_control_state (struct execution_control_state *ecs)
{
- init_wait_for_inferior ();
- clear_proceed_status ();
- stop_soon_quietly = 1;
- trap_expected = 0;
- wait_for_inferior ();
- normal_stop ();
+ ecs->random_signal = 0;
+ ecs->remove_breakpoints_on_following_step = 0;
+ ecs->handling_longjmp = 0; /* FIXME */
+ ecs->update_step_sp = 0;
+ ecs->stepping_through_solib_after_catch = 0;
+ ecs->stepping_through_solib_catchpoints = NULL;
+ ecs->enable_hw_watchpoints_after_wait = 0;
+ ecs->stepping_through_sigtramp = 0;
+ ecs->sal = find_pc_line (prev_pc, 0);
+ ecs->current_line = ecs->sal.line;
+ ecs->current_symtab = ecs->sal.symtab;
+ ecs->infwait_state = infwait_normal_state;
+ ecs->waiton_pid = -1;
+ ecs->wp = &(ecs->ws);
}
-/* Initialize static vars when a new inferior begins. */
-
-void
-init_wait_for_inferior ()
+/* Call this function before setting step_resume_breakpoint, as a
+ sanity check. There should never be more than one step-resume
+ breakpoint per thread, so we should never be setting a new
+ step_resume_breakpoint when one is already active. */
+static void
+check_for_old_step_resume_breakpoint (void)
{
- /* These are meaningless until the first time through wait_for_inferior. */
- prev_pc = 0;
- prev_sp = 0;
- prev_func_start = 0;
- prev_func_name = NULL;
-
- trap_expected_after_continue = 0;
- breakpoints_inserted = 0;
- mark_breakpoints_out ();
- stop_signal = 0; /* Don't confuse first call to proceed(). */
+ if (step_resume_breakpoint)
+ warning ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
}
-
-/* Attach to process PID, then initialize for debugging it
- and wait for the trace-trap that results from attaching. */
+/* Given an execution control state that has been freshly filled in
+ by an event from the inferior, figure out what it means and take
+ appropriate action. */
void
-child_attach (args, from_tty)
- char *args;
- int from_tty;
+handle_inferior_event (struct execution_control_state *ecs)
{
- char *exec_file;
- int pid;
+ CORE_ADDR tmp;
+ int stepped_after_stopped_by_watchpoint;
- dont_repeat();
+ /* Keep this extra brace for now, minimizes diffs. */
+ {
+ switch (ecs->infwait_state)
+ {
+ case infwait_normal_state:
+ /* Since we've done a wait, we have a new event. Don't
+ carry over any expectations about needing to step over a
+ breakpoint. */
+ thread_step_needed = 0;
+
+ /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
+ is serviced in this loop, below. */
+ if (ecs->enable_hw_watchpoints_after_wait)
+ {
+ TARGET_ENABLE_HW_WATCHPOINTS (inferior_pid);
+ ecs->enable_hw_watchpoints_after_wait = 0;
+ }
+ stepped_after_stopped_by_watchpoint = 0;
+ break;
+
+ case infwait_thread_hop_state:
+ insert_breakpoints ();
+
+ /* We need to restart all the threads now,
+ * unles we're running in scheduler-locked mode.
+ * FIXME: shouldn't we look at currently_stepping ()?
+ */
+ if (scheduler_mode == schedlock_on)
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ else
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ ecs->infwait_state = infwait_normal_state;
+ prepare_to_wait (ecs);
+ return;
+
+ case infwait_nullified_state:
+ break;
+
+ case infwait_nonstep_watch_state:
+ insert_breakpoints ();
+
+ /* FIXME-maybe: is this cleaner than setting a flag? Does it
+ handle things like signals arriving and other things happening
+ in combination correctly? */
+ stepped_after_stopped_by_watchpoint = 1;
+ break;
+ }
+ ecs->infwait_state = infwait_normal_state;
- if (!args)
- error_no_arg ("process-id to attach");
+ flush_cached_frames ();
-#ifndef ATTACH_DETACH
- error ("Can't attach to a process on this machine.");
-#else
- pid = atoi (args);
+ /* If it's a new process, add it to the thread database */
- if (pid == getpid()) /* Trying to masturbate? */
- error ("I refuse to debug myself!");
+ ecs->new_thread_event = ((ecs->pid != inferior_pid) && !in_thread_list (ecs->pid));
- if (target_has_execution)
- {
- if (query ("A program is being debugged already. Kill it? "))
- target_kill ();
- else
- error ("Inferior not killed.");
- }
-
- exec_file = (char *) get_exec_file (1);
+ if (ecs->ws.kind != TARGET_WAITKIND_EXITED
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
+ && ecs->new_thread_event)
+ {
+ add_thread (ecs->pid);
- if (from_tty)
- {
- printf ("Attaching program: %s pid %d\n",
- exec_file, pid);
- fflush (stdout);
- }
+ printf_filtered ("[New %s]\n", target_pid_or_tid_to_str (ecs->pid));
- attach (pid);
- inferior_pid = pid;
- push_target (&child_ops);
+#if 0
+ /* NOTE: This block is ONLY meant to be invoked in case of a
+ "thread creation event"! If it is invoked for any other
+ sort of event (such as a new thread landing on a breakpoint),
+ the event will be discarded, which is almost certainly
+ a bad thing!
+
+ To avoid this, the low-level module (eg. target_wait)
+ should call in_thread_list and add_thread, so that the
+ new thread is known by the time we get here. */
+
+ /* We may want to consider not doing a resume here in order
+ to give the user a chance to play with the new thread.
+ It might be good to make that a user-settable option. */
+
+ /* At this point, all threads are stopped (happens
+ automatically in either the OS or the native code).
+ Therefore we need to continue all threads in order to
+ make progress. */
+
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+#endif
+ }
- mark_breakpoints_out ();
- target_terminal_init ();
- clear_proceed_status ();
- stop_soon_quietly = 1;
- /*proceed (-1, 0, -2);*/
- target_terminal_inferior ();
- wait_for_inferior ();
+ switch (ecs->ws.kind)
+ {
+ case TARGET_WAITKIND_LOADED:
+ /* Ignore gracefully during startup of the inferior, as it
+ might be the shell which has just loaded some objects,
+ otherwise add the symbols for the newly loaded objects. */
#ifdef SOLIB_ADD
- SOLIB_ADD ((char *)0, from_tty, (struct target_ops *)0);
+ if (!stop_soon_quietly)
+ {
+ /* Remove breakpoints, SOLIB_ADD might adjust
+ breakpoint addresses via breakpoint_re_set. */
+ if (breakpoints_inserted)
+ remove_breakpoints ();
+
+ /* Check for any newly added shared libraries if we're
+ supposed to be adding them automatically. */
+ if (auto_solib_add)
+ {
+ /* Switch terminal for any messages produced by
+ breakpoint_re_set. */
+ target_terminal_ours_for_output ();
+ SOLIB_ADD (NULL, 0, NULL);
+ target_terminal_inferior ();
+ }
+
+ /* Reinsert breakpoints and continue. */
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+ }
#endif
- normal_stop ();
-#endif /* ATTACH_DETACH */
-}
-\f
-/* Wait for control to return from inferior to debugger.
- If inferior gets a signal, we may decide to start it up again
- instead of returning. That is why there is a loop in this function.
- When this function actually returns it means the inferior
- should be left stopped and GDB should read more commands. */
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+
+ case TARGET_WAITKIND_SPURIOUS:
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+
+ case TARGET_WAITKIND_EXITED:
+ target_terminal_ours (); /* Must do this before mourn anyway */
+ annotate_exited (ecs->ws.value.integer);
+ if (ecs->ws.value.integer)
+ printf_filtered ("\nProgram exited with code 0%o.\n",
+ (unsigned int) ecs->ws.value.integer);
+ else
+ printf_filtered ("\nProgram exited normally.\n");
+
+ /* Record the exit code in the convenience variable $_exitcode, so
+ that the user can inspect this again later. */
+ set_internalvar (lookup_internalvar ("_exitcode"),
+ value_from_longest (builtin_type_int,
+ (LONGEST) ecs->ws.value.integer));
+ gdb_flush (gdb_stdout);
+ target_mourn_inferior ();
+ singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
+ stop_print_frame = 0;
+ stop_stepping (ecs);
+ return;
+
+ case TARGET_WAITKIND_SIGNALLED:
+ stop_print_frame = 0;
+ stop_signal = ecs->ws.value.sig;
+ target_terminal_ours (); /* Must do this before mourn anyway */
+ annotate_signalled ();
+
+ /* This looks pretty bogus to me. Doesn't TARGET_WAITKIND_SIGNALLED
+ mean it is already dead? This has been here since GDB 2.8, so
+ perhaps it means rms didn't understand unix waitstatuses?
+ For the moment I'm just kludging around this in remote.c
+ rather than trying to change it here --kingdon, 5 Dec 1994. */
+ target_kill (); /* kill mourns as well */
+
+ printf_filtered ("\nProgram terminated with signal ");
+ annotate_signal_name ();
+ printf_filtered ("%s", target_signal_to_name (stop_signal));
+ annotate_signal_name_end ();
+ printf_filtered (", ");
+ annotate_signal_string ();
+ printf_filtered ("%s", target_signal_to_string (stop_signal));
+ annotate_signal_string_end ();
+ printf_filtered (".\n");
+
+ printf_filtered ("The program no longer exists.\n");
+ gdb_flush (gdb_stdout);
+ singlestep_breakpoints_inserted_p = 0; /*SOFTWARE_SINGLE_STEP_P */
+ stop_stepping (ecs);
+ return;
+
+ /* The following are the only cases in which we keep going;
+ the above cases end in a continue or goto. */
+ case TARGET_WAITKIND_FORKED:
+ stop_signal = TARGET_SIGNAL_TRAP;
+ pending_follow.kind = ecs->ws.kind;
+
+ /* Ignore fork events reported for the parent; we're only
+ interested in reacting to forks of the child. Note that
+ we expect the child's fork event to be available if we
+ waited for it now. */
+ if (inferior_pid == ecs->pid)
+ {
+ pending_follow.fork_event.saw_parent_fork = 1;
+ pending_follow.fork_event.parent_pid = ecs->pid;
+ pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
+ prepare_to_wait (ecs);
+ return;
+ }
+ else
+ {
+ pending_follow.fork_event.saw_child_fork = 1;
+ pending_follow.fork_event.child_pid = ecs->pid;
+ pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
+ }
-void
-wait_for_inferior ()
-{
- WAITTYPE w;
- int another_trap;
- int random_signal;
- CORE_ADDR stop_sp;
- CORE_ADDR stop_func_start;
- char *stop_func_name;
- CORE_ADDR prologue_pc, tmp;
- int stop_step_resume_break;
- struct symtab_and_line sal;
- int remove_breakpoints_on_following_step = 0;
- int current_line;
- int handling_longjmp = 0; /* FIXME */
-
- sal = find_pc_line(prev_pc, 0);
- current_line = sal.line;
+ stop_pc = read_pc_pid (ecs->pid);
+ ecs->saved_inferior_pid = inferior_pid;
+ inferior_pid = ecs->pid;
+ stop_bpstat = bpstat_stop_status
+ (&stop_pc,
+ (DECR_PC_AFTER_BREAK ?
+ (prev_pc != stop_pc - DECR_PC_AFTER_BREAK
+ && currently_stepping (ecs))
+ : 0)
+ );
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ inferior_pid = ecs->saved_inferior_pid;
+ goto process_event_stop_test;
+
+ /* If this a platform which doesn't allow a debugger to touch a
+ vfork'd inferior until after it exec's, then we'd best keep
+ our fingers entirely off the inferior, other than continuing
+ it. This has the unfortunate side-effect that catchpoints
+ of vforks will be ignored. But since the platform doesn't
+ allow the inferior be touched at vfork time, there's really
+ little choice. */
+ case TARGET_WAITKIND_VFORKED:
+ stop_signal = TARGET_SIGNAL_TRAP;
+ pending_follow.kind = ecs->ws.kind;
+
+ /* Is this a vfork of the parent? If so, then give any
+ vfork catchpoints a chance to trigger now. (It's
+ dangerous to do so if the child canot be touched until
+ it execs, and the child has not yet exec'd. We probably
+ should warn the user to that effect when the catchpoint
+ triggers...) */
+ if (ecs->pid == inferior_pid)
+ {
+ pending_follow.fork_event.saw_parent_fork = 1;
+ pending_follow.fork_event.parent_pid = ecs->pid;
+ pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
+ }
- while (1)
- {
- /* Clean up saved state that will become invalid. */
- pc_changed = 0;
- flush_cached_frames ();
- registers_changed ();
+ /* If we've seen the child's vfork event but cannot really touch
+ the child until it execs, then we must continue the child now.
+ Else, give any vfork catchpoints a chance to trigger now. */
+ else
+ {
+ pending_follow.fork_event.saw_child_fork = 1;
+ pending_follow.fork_event.child_pid = ecs->pid;
+ pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
+ target_post_startup_inferior (pending_follow.fork_event.child_pid);
+ follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
+ if (follow_vfork_when_exec)
+ {
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ }
- target_wait (&w);
+ stop_pc = read_pc ();
+ stop_bpstat = bpstat_stop_status
+ (&stop_pc,
+ (DECR_PC_AFTER_BREAK ?
+ (prev_pc != stop_pc - DECR_PC_AFTER_BREAK
+ && currently_stepping (ecs))
+ : 0)
+ );
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ goto process_event_stop_test;
+
+ case TARGET_WAITKIND_EXECD:
+ stop_signal = TARGET_SIGNAL_TRAP;
+
+ /* Is this a target which reports multiple exec events per actual
+ call to exec()? (HP-UX using ptrace does, for example.) If so,
+ ignore all but the last one. Just resume the exec'r, and wait
+ for the next exec event. */
+ if (inferior_ignoring_leading_exec_events)
+ {
+ inferior_ignoring_leading_exec_events--;
+ if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.parent_pid);
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ inferior_ignoring_leading_exec_events =
+ target_reported_exec_events_per_exec_call () - 1;
+
+ pending_follow.execd_pathname =
+ savestring (ecs->ws.value.execd_pathname,
+ strlen (ecs->ws.value.execd_pathname));
+
+ /* Did inferior_pid exec, or did a (possibly not-yet-followed)
+ child of a vfork exec?
+
+ ??rehrauer: This is unabashedly an HP-UX specific thing. On
+ HP-UX, events associated with a vforking inferior come in
+ threes: a vfork event for the child (always first), followed
+ a vfork event for the parent and an exec event for the child.
+ The latter two can come in either order.
+
+ If we get the parent vfork event first, life's good: We follow
+ either the parent or child, and then the child's exec event is
+ a "don't care".
+
+ But if we get the child's exec event first, then we delay
+ responding to it until we handle the parent's vfork. Because,
+ otherwise we can't satisfy a "catch vfork". */
+ if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ {
+ pending_follow.fork_event.saw_child_exec = 1;
+
+ /* On some targets, the child must be resumed before
+ the parent vfork event is delivered. A single-step
+ suffices. */
+ if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+ /* We expect the parent vfork event to be available now. */
+ prepare_to_wait (ecs);
+ return;
+ }
-#ifdef SIGTRAP_STOP_AFTER_LOAD
+ /* This causes the eventpoints and symbol table to be reset. Must
+ do this now, before trying to determine whether to stop. */
+ follow_exec (inferior_pid, pending_follow.execd_pathname);
+ free (pending_follow.execd_pathname);
+
+ stop_pc = read_pc_pid (ecs->pid);
+ ecs->saved_inferior_pid = inferior_pid;
+ inferior_pid = ecs->pid;
+ stop_bpstat = bpstat_stop_status
+ (&stop_pc,
+ (DECR_PC_AFTER_BREAK ?
+ (prev_pc != stop_pc - DECR_PC_AFTER_BREAK
+ && currently_stepping (ecs))
+ : 0)
+ );
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+ inferior_pid = ecs->saved_inferior_pid;
+ goto process_event_stop_test;
+
+ /* These syscall events are returned on HP-UX, as part of its
+ implementation of page-protection-based "hardware" watchpoints.
+ HP-UX has unfortunate interactions between page-protections and
+ some system calls. Our solution is to disable hardware watches
+ when a system call is entered, and reenable them when the syscall
+ completes. The downside of this is that we may miss the precise
+ point at which a watched piece of memory is modified. "Oh well."
+
+ Note that we may have multiple threads running, which may each
+ enter syscalls at roughly the same time. Since we don't have a
+ good notion currently of whether a watched piece of memory is
+ thread-private, we'd best not have any page-protections active
+ when any thread is in a syscall. Thus, we only want to reenable
+ hardware watches when no threads are in a syscall.
+
+ Also, be careful not to try to gather much state about a thread
+ that's in a syscall. It's frequently a losing proposition. */
+ case TARGET_WAITKIND_SYSCALL_ENTRY:
+ number_of_threads_in_syscalls++;
+ if (number_of_threads_in_syscalls == 1)
+ {
+ TARGET_DISABLE_HW_WATCHPOINTS (inferior_pid);
+ }
+ resume (0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+
+ /* Before examining the threads further, step this thread to
+ get it entirely out of the syscall. (We get notice of the
+ event when the thread is just on the verge of exiting a
+ syscall. Stepping one instruction seems to get it back
+ into user code.)
+
+ Note that although the logical place to reenable h/w watches
+ is here, we cannot. We cannot reenable them before stepping
+ the thread (this causes the next wait on the thread to hang).
+
+ Nor can we enable them after stepping until we've done a wait.
+ Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
+ here, which will be serviced immediately after the target
+ is waited on. */
+ case TARGET_WAITKIND_SYSCALL_RETURN:
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+
+ if (number_of_threads_in_syscalls > 0)
+ {
+ number_of_threads_in_syscalls--;
+ ecs->enable_hw_watchpoints_after_wait =
+ (number_of_threads_in_syscalls == 0);
+ }
+ prepare_to_wait (ecs);
+ return;
- /* Somebody called load(2), and it gave us a "trap signal after load".
- Ignore it gracefully. */
+ case TARGET_WAITKIND_STOPPED:
+ stop_signal = ecs->ws.value.sig;
+ break;
+ }
- SIGTRAP_STOP_AFTER_LOAD (w);
-#endif
+ /* We may want to consider not doing a resume here in order to give
+ the user a chance to play with the new thread. It might be good
+ to make that a user-settable option. */
- /* See if the process still exists; clean up if it doesn't. */
- if (WIFEXITED (w))
- {
- target_terminal_ours (); /* Must do this before mourn anyway */
- if (WEXITSTATUS (w))
- printf_filtered ("\nProgram exited with code 0%o.\n",
- (unsigned int)WEXITSTATUS (w));
- else
- if (!batch_mode())
- printf_filtered ("\nProgram exited normally.\n");
- fflush (stdout);
- target_mourn_inferior ();
-#ifdef NO_SINGLE_STEP
- one_stepped = 0;
+ /* At this point, all threads are stopped (happens automatically in
+ either the OS or the native code). Therefore we need to continue
+ all threads in order to make progress. */
+ if (ecs->new_thread_event)
+ {
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ stop_pc = read_pc_pid (ecs->pid);
+
+ /* See if a thread hit a thread-specific breakpoint that was meant for
+ another thread. If so, then step that thread past the breakpoint,
+ and continue it. */
+
+ if (stop_signal == TARGET_SIGNAL_TRAP)
+ {
+ if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
+ ecs->random_signal = 0;
+ else if (breakpoints_inserted
+ && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
+ {
+ ecs->random_signal = 0;
+ if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
+ ecs->pid))
+ {
+ int remove_status;
+
+ /* Saw a breakpoint, but it was hit by the wrong thread.
+ Just continue. */
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->pid);
+
+ remove_status = remove_breakpoints ();
+ /* Did we fail to remove breakpoints? If so, try
+ to set the PC past the bp. (There's at least
+ one situation in which we can fail to remove
+ the bp's: On HP-UX's that use ttrace, we can't
+ change the address space of a vforking child
+ process until the child exits (well, okay, not
+ then either :-) or execs. */
+ if (remove_status != 0)
+ {
+ write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4, ecs->pid);
+ }
+ else
+ { /* Single step */
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+ /* FIXME: What if a signal arrives instead of the
+ single-step happening? */
+
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->ws);
+ ecs->infwait_state = infwait_thread_hop_state;
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* We need to restart all the threads now,
+ * unles we're running in scheduler-locked mode.
+ * FIXME: shouldn't we look at currently_stepping ()?
+ */
+ if (scheduler_mode == schedlock_on)
+ target_resume (ecs->pid, 0, TARGET_SIGNAL_0);
+ else
+ target_resume (-1, 0, TARGET_SIGNAL_0);
+ prepare_to_wait (ecs);
+ return;
+ }
+ else
+ {
+ /* This breakpoint matches--either it is the right
+ thread or it's a generic breakpoint for all threads.
+ Remember that we'll need to step just _this_ thread
+ on any following user continuation! */
+ thread_step_needed = 1;
+ }
+ }
+ }
+ else
+ ecs->random_signal = 1;
+
+ /* See if something interesting happened to the non-current thread. If
+ so, then switch to that thread, and eventually give control back to
+ the user.
+
+ Note that if there's any kind of pending follow (i.e., of a fork,
+ vfork or exec), we don't want to do this now. Rather, we'll let
+ the next resume handle it. */
+ if ((ecs->pid != inferior_pid) &&
+ (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
+ {
+ int printed = 0;
+
+ /* If it's a random signal for a non-current thread, notify user
+ if he's expressed an interest. */
+ if (ecs->random_signal
+ && signal_print[stop_signal])
+ {
+/* ??rehrauer: I don't understand the rationale for this code. If the
+ inferior will stop as a result of this signal, then the act of handling
+ the stop ought to print a message that's couches the stoppage in user
+ terms, e.g., "Stopped for breakpoint/watchpoint". If the inferior
+ won't stop as a result of the signal -- i.e., if the signal is merely
+ a side-effect of something GDB's doing "under the covers" for the
+ user, such as stepping threads over a breakpoint they shouldn't stop
+ for -- then the message seems to be a serious annoyance at best.
+
+ For now, remove the message altogether. */
+#if 0
+ printed = 1;
+ target_terminal_ours_for_output ();
+ printf_filtered ("\nProgram received signal %s, %s.\n",
+ target_signal_to_name (stop_signal),
+ target_signal_to_string (stop_signal));
+ gdb_flush (gdb_stdout);
#endif
- stop_print_frame = 0;
- break;
- }
- else if (!WIFSTOPPED (w))
+ }
+
+ /* If it's not SIGTRAP and not a signal we want to stop for, then
+ continue the thread. */
+
+ if (stop_signal != TARGET_SIGNAL_TRAP
+ && !signal_stop[stop_signal])
+ {
+ if (printed)
+ target_terminal_inferior ();
+
+ /* Clear the signal if it should not be passed. */
+ if (signal_program[stop_signal] == 0)
+ stop_signal = TARGET_SIGNAL_0;
+
+ target_resume (ecs->pid, 0, stop_signal);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It's a SIGTRAP or a signal we're interested in. Switch threads,
+ and fall into the rest of wait_for_inferior(). */
+
+ /* Save infrun state for the old thread. */
+ save_infrun_state (inferior_pid, prev_pc,
+ prev_func_start, prev_func_name,
+ trap_expected, step_resume_breakpoint,
+ through_sigtramp_breakpoint,
+ step_range_start, step_range_end,
+ step_frame_address, ecs->handling_longjmp,
+ ecs->another_trap,
+ ecs->stepping_through_solib_after_catch,
+ ecs->stepping_through_solib_catchpoints,
+ ecs->stepping_through_sigtramp);
+
+ if (may_switch_from_inferior_pid)
+ switched_from_inferior_pid = inferior_pid;
+
+ inferior_pid = ecs->pid;
+
+ /* Load infrun state for the new thread. */
+ load_infrun_state (inferior_pid, &prev_pc,
+ &prev_func_start, &prev_func_name,
+ &trap_expected, &step_resume_breakpoint,
+ &through_sigtramp_breakpoint,
+ &step_range_start, &step_range_end,
+ &step_frame_address, &ecs->handling_longjmp,
+ &ecs->another_trap,
+ &ecs->stepping_through_solib_after_catch,
+ &ecs->stepping_through_solib_catchpoints,
+ &ecs->stepping_through_sigtramp);
+
+ if (context_hook)
+ context_hook (pid_to_thread_id (ecs->pid));
+
+ printf_filtered ("[Switching to %s]\n", target_pid_to_str (ecs->pid));
+ flush_cached_frames ();
+ }
+
+ if (SOFTWARE_SINGLE_STEP_P && singlestep_breakpoints_inserted_p)
+ {
+ /* Pull the single step breakpoints out of the target. */
+ SOFTWARE_SINGLE_STEP (0, 0);
+ singlestep_breakpoints_inserted_p = 0;
+ }
+
+ /* If PC is pointing at a nullified instruction, then step beyond
+ it so that the user won't be confused when GDB appears to be ready
+ to execute it. */
+
+ /* if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
+ if (INSTRUCTION_NULLIFIED)
+ {
+ registers_changed ();
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0);
+
+ /* We may have received a signal that we want to pass to
+ the inferior; therefore, we must not clobber the waitstatus
+ in WS. */
+
+ ecs->infwait_state = infwait_nullified_state;
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->tmpstatus);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It may not be necessary to disable the watchpoint to stop over
+ it. For example, the PA can (with some kernel cooperation)
+ single step over a watchpoint without disabling the watchpoint. */
+ if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
+ {
+ resume (1, 0);
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It is far more common to need to disable a watchpoint to step
+ the inferior over it. FIXME. What else might a debug
+ register or page protection watchpoint scheme need here? */
+ if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
+ {
+ /* At this point, we are stopped at an instruction which has
+ attempted to write to a piece of memory under control of
+ a watchpoint. The instruction hasn't actually executed
+ yet. If we were to evaluate the watchpoint expression
+ now, we would get the old value, and therefore no change
+ would seem to have occurred.
+
+ In order to make watchpoints work `right', we really need
+ to complete the memory write, and then evaluate the
+ watchpoint expression. The following code does that by
+ removing the watchpoint (actually, all watchpoints and
+ breakpoints), single-stepping the target, re-inserting
+ watchpoints, and then falling through to let normal
+ single-step processing handle proceed. Since this
+ includes evaluating watchpoints, things will come to a
+ stop in the correct manner. */
+
+ write_pc (stop_pc - DECR_PC_AFTER_BREAK);
+
+ remove_breakpoints ();
+ registers_changed ();
+ target_resume (ecs->pid, 1, TARGET_SIGNAL_0); /* Single step */
+
+ ecs->waiton_pid = ecs->pid;
+ ecs->wp = &(ecs->ws);
+ ecs->infwait_state = infwait_nonstep_watch_state;
+ prepare_to_wait (ecs);
+ return;
+ }
+
+ /* It may be possible to simply continue after a watchpoint. */
+ if (HAVE_CONTINUABLE_WATCHPOINT)
+ STOPPED_BY_WATCHPOINT (ecs->ws);
+
+ ecs->stop_func_start = 0;
+ ecs->stop_func_end = 0;
+ ecs->stop_func_name = 0;
+ /* Don't care about return value; stop_func_start and stop_func_name
+ will both be 0 if it doesn't work. */
+ find_pc_partial_function (stop_pc, &ecs->stop_func_name,
+ &ecs->stop_func_start, &ecs->stop_func_end);
+ ecs->stop_func_start += FUNCTION_START_OFFSET;
+ ecs->another_trap = 0;
+ bpstat_clear (&stop_bpstat);
+ stop_step = 0;
+ stop_stack_dummy = 0;
+ stop_print_frame = 1;
+ ecs->random_signal = 0;
+ stopped_by_random_signal = 0;
+ breakpoints_failed = 0;
+
+ /* Look at the cause of the stop, and decide what to do.
+ The alternatives are:
+ 1) break; to really stop and return to the debugger,
+ 2) drop through to start up again
+ (set ecs->another_trap to 1 to single step once)
+ 3) set ecs->random_signal to 1, and the decision between 1 and 2
+ will be made according to the signal handling tables. */
+
+ /* First, distinguish signals caused by the debugger from signals
+ that have to do with the program's own actions.
+ Note that breakpoint insns may cause SIGTRAP or SIGILL
+ or SIGEMT, depending on the operating system version.
+ Here we detect when a SIGILL or SIGEMT is really a breakpoint
+ and change it to SIGTRAP. */
+
+ if (stop_signal == TARGET_SIGNAL_TRAP
+ || (breakpoints_inserted &&
+ (stop_signal == TARGET_SIGNAL_ILL
+ || stop_signal == TARGET_SIGNAL_EMT
+ ))
+ || stop_soon_quietly)
+ {
+ if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
+ {
+ stop_print_frame = 0;
+ stop_stepping (ecs);
+ return;
+ }
+ if (stop_soon_quietly)
+ {
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* Don't even think about breakpoints
+ if just proceeded over a breakpoint.
+
+ However, if we are trying to proceed over a breakpoint
+ and end up in sigtramp, then through_sigtramp_breakpoint
+ will be set and we should check whether we've hit the
+ step breakpoint. */
+ if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
+ && through_sigtramp_breakpoint == NULL)
+ bpstat_clear (&stop_bpstat);
+ else
+ {
+ /* See if there is a breakpoint at the current PC. */
+ stop_bpstat = bpstat_stop_status
+ (&stop_pc,
+ (DECR_PC_AFTER_BREAK ?
+ /* Notice the case of stepping through a jump
+ that lands just after a breakpoint.
+ Don't confuse that with hitting the breakpoint.
+ What we check for is that 1) stepping is going on
+ and 2) the pc before the last insn does not match
+ the address of the breakpoint before the current pc
+ and 3) we didn't hit a breakpoint in a signal handler
+ without an intervening stop in sigtramp, which is
+ detected by a new stack pointer value below
+ any usual function calling stack adjustments. */
+ (currently_stepping (ecs)
+ && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
+ && !(step_range_end
+ && INNER_THAN (read_sp (), (step_sp - 16)))) :
+ 0)
+ );
+ /* Following in case break condition called a
+ function. */
+ stop_print_frame = 1;
+ }
+
+ if (stop_signal == TARGET_SIGNAL_TRAP)
+ ecs->random_signal
+ = !(bpstat_explains_signal (stop_bpstat)
+ || trap_expected
+ || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
+ && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ())))
+ || (step_range_end && step_resume_breakpoint == NULL));
+
+ else
+ {
+ ecs->random_signal
+ = !(bpstat_explains_signal (stop_bpstat)
+ /* End of a stack dummy. Some systems (e.g. Sony
+ news) give another signal besides SIGTRAP, so
+ check here as well as above. */
+ || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
+ && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ())))
+ );
+ if (!ecs->random_signal)
+ stop_signal = TARGET_SIGNAL_TRAP;
+ }
+ }
+
+ /* When we reach this point, we've pretty much decided
+ that the reason for stopping must've been a random
+ (unexpected) signal. */
+
+ else
+ ecs->random_signal = 1;
+ /* If a fork, vfork or exec event was seen, then there are two
+ possible responses we can make:
+
+ 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
+ then we must stop now and issue a prompt. We will resume
+ the inferior when the user tells us to.
+ 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
+ then we must resume the inferior now and keep checking.
+
+ In either case, we must take appropriate steps to "follow" the
+ the fork/vfork/exec when the inferior is resumed. For example,
+ if follow-fork-mode is "child", then we must detach from the
+ parent inferior and follow the new child inferior.
+
+ In either case, setting pending_follow causes the next resume()
+ to take the appropriate following action. */
+ process_event_stop_test:
+ if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
+ {
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ trap_expected = 1;
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+ else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
+ {
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+ else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
+ {
+ pending_follow.kind = ecs->ws.kind;
+ if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
+ {
+ trap_expected = 1;
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ /* For the program's own signals, act according to
+ the signal handling tables. */
+
+ if (ecs->random_signal)
+ {
+ /* Signal not for debugging purposes. */
+ int printed = 0;
+
+ stopped_by_random_signal = 1;
+
+ if (signal_print[stop_signal])
+ {
+ printed = 1;
+ target_terminal_ours_for_output ();
+ annotate_signal ();
+ printf_filtered ("\nProgram received signal ");
+ annotate_signal_name ();
+ printf_filtered ("%s", target_signal_to_name (stop_signal));
+ annotate_signal_name_end ();
+ printf_filtered (", ");
+ annotate_signal_string ();
+ printf_filtered ("%s", target_signal_to_string (stop_signal));
+ annotate_signal_string_end ();
+ printf_filtered (".\n");
+ gdb_flush (gdb_stdout);
+ }
+ if (signal_stop[stop_signal])
+ {
+ stop_stepping (ecs);
+ return;
+ }
+ /* If not going to stop, give terminal back
+ if we took it away. */
+ else if (printed)
+ target_terminal_inferior ();
+
+ /* Clear the signal if it should not be passed. */
+ if (signal_program[stop_signal] == 0)
+ stop_signal = TARGET_SIGNAL_0;
+
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going.
+
+ This used to jump to step_over_function if we are stepping,
+ which is wrong.
+
+ Suppose the user does a `next' over a function call, and while
+ that call is in progress, the inferior receives a signal for
+ which GDB does not stop (i.e., signal_stop[SIG] is false). In
+ that case, when we reach this point, there is already a
+ step-resume breakpoint established, right where it should be:
+ immediately after the function call the user is "next"-ing
+ over. If we call step_over_function now, two bad things
+ happen:
+
+ - we'll create a new breakpoint, at wherever the current
+ frame's return address happens to be. That could be
+ anywhere, depending on what function call happens to be on
+ the top of the stack at that point. Point is, it's probably
+ not where we need it.
+
+ - the existing step-resume breakpoint (which is at the correct
+ address) will get orphaned: step_resume_breakpoint will point
+ to the new breakpoint, and the old step-resume breakpoint
+ will never be cleaned up.
+
+ The old behavior was meant to help HP-UX single-step out of
+ sigtramps. It would place the new breakpoint at prev_pc, which
+ was certainly wrong. I don't know the details there, so fixing
+ this probably breaks that. As with anything else, it's up to
+ the HP-UX maintainer to furnish a fix that doesn't break other
+ platforms. --JimB, 20 May 1999 */
+ check_sigtramp2 (ecs);
+ }
+
+ /* Handle cases caused by hitting a breakpoint. */
+ {
+ CORE_ADDR jmp_buf_pc;
+ struct bpstat_what what;
+
+ what = bpstat_what (stop_bpstat);
+
+ if (what.call_dummy)
{
- stop_print_frame = 0;
- stop_signal = WTERMSIG (w);
- target_terminal_ours (); /* Must do this before mourn anyway */
- target_kill (); /* kill mourns as well */
-#ifdef PRINT_RANDOM_SIGNAL
- printf_filtered ("\nProgram terminated: ");
- PRINT_RANDOM_SIGNAL (stop_signal);
-#else
- printf_filtered ("\nProgram terminated with signal %d, %s\n",
- stop_signal, safe_strsignal (stop_signal));
-#endif
- printf_filtered ("The inferior process no longer exists.\n");
- fflush (stdout);
-#ifdef NO_SINGLE_STEP
- one_stepped = 0;
+ stop_stack_dummy = 1;
+#ifdef HP_OS_BUG
+ trap_expected_after_continue = 1;
#endif
- break;
}
-
-#ifdef NO_SINGLE_STEP
- if (one_stepped)
- single_step (0); /* This actually cleans up the ss */
-#endif /* NO_SINGLE_STEP */
-
- stop_pc = read_pc ();
- set_current_frame ( create_new_frame (read_register (FP_REGNUM),
- read_pc ()));
-
- stop_frame_address = FRAME_FP (get_current_frame ());
- stop_sp = read_register (SP_REGNUM);
- stop_func_start = 0;
- stop_func_name = 0;
- /* Don't care about return value; stop_func_start and stop_func_name
- will both be 0 if it doesn't work. */
- (void) find_pc_partial_function (stop_pc, &stop_func_name,
- &stop_func_start);
- stop_func_start += FUNCTION_START_OFFSET;
- another_trap = 0;
- bpstat_clear (&stop_bpstat);
- stop_step = 0;
- stop_stack_dummy = 0;
- stop_print_frame = 1;
- stop_step_resume_break = 0;
- random_signal = 0;
- stopped_by_random_signal = 0;
- breakpoints_failed = 0;
-
- /* Look at the cause of the stop, and decide what to do.
- The alternatives are:
- 1) break; to really stop and return to the debugger,
- 2) drop through to start up again
- (set another_trap to 1 to single step once)
- 3) set random_signal to 1, and the decision between 1 and 2
- will be made according to the signal handling tables. */
-
- stop_signal = WSTOPSIG (w);
-
- /* First, distinguish signals caused by the debugger from signals
- that have to do with the program's own actions.
- Note that breakpoint insns may cause SIGTRAP or SIGILL
- or SIGEMT, depending on the operating system version.
- Here we detect when a SIGILL or SIGEMT is really a breakpoint
- and change it to SIGTRAP. */
-
- if (stop_signal == SIGTRAP
- || (breakpoints_inserted &&
- (stop_signal == SIGILL
-#ifdef SIGEMT
- || stop_signal == SIGEMT
-#endif
- ))
- || stop_soon_quietly)
+
+ switch (what.main_action)
{
- if (stop_signal == SIGTRAP && stop_after_trap)
+ case BPSTAT_WHAT_SET_LONGJMP_RESUME:
+ /* If we hit the breakpoint at longjmp, disable it for the
+ duration of this command. Then, install a temporary
+ breakpoint at the target of the jmp_buf. */
+ disable_longjmp_breakpoint ();
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+ if (!GET_LONGJMP_TARGET (&jmp_buf_pc))
{
- stop_print_frame = 0;
- break;
+ keep_going (ecs);
+ return;
}
- if (stop_soon_quietly)
- break;
- /* Don't even think about breakpoints
- if just proceeded over a breakpoint.
+ /* Need to blow away step-resume breakpoint, as it
+ interferes with us */
+ if (step_resume_breakpoint != NULL)
+ {
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
+ }
+ /* Not sure whether we need to blow this away too, but probably
+ it is like the step-resume breakpoint. */
+ if (through_sigtramp_breakpoint != NULL)
+ {
+ delete_breakpoint (through_sigtramp_breakpoint);
+ through_sigtramp_breakpoint = NULL;
+ }
- However, if we are trying to proceed over a breakpoint
- and end up in sigtramp, then step_resume_break_address
- will be set and we should check whether we've hit the
- step breakpoint. */
- if (stop_signal == SIGTRAP && trap_expected
- && step_resume_break_address == 0)
- bpstat_clear (&stop_bpstat);
+#if 0
+ /* FIXME - Need to implement nested temporary breakpoints */
+ if (step_over_calls > 0)
+ set_longjmp_resume_breakpoint (jmp_buf_pc,
+ get_current_frame ());
else
+#endif /* 0 */
+ set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
+ ecs->handling_longjmp = 1; /* FIXME */
+ keep_going (ecs);
+ return;
+
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
+ case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
+#if 0
+ /* FIXME - Need to implement nested temporary breakpoints */
+ if (step_over_calls
+ && (INNER_THAN (FRAME_FP (get_current_frame ()),
+ step_frame_address)))
{
- /* See if there is a breakpoint at the current PC. */
-#if DECR_PC_AFTER_BREAK
- /* Notice the case of stepping through a jump
- that lands just after a breakpoint.
- Don't confuse that with hitting the breakpoint.
- What we check for is that 1) stepping is going on
- and 2) the pc before the last insn does not match
- the address of the breakpoint before the current pc. */
- if (prev_pc == stop_pc - DECR_PC_AFTER_BREAK
- || !step_range_end
- || step_resume_break_address
- || handling_longjmp /* FIXME */)
-#endif /* DECR_PC_AFTER_BREAK not zero */
- {
- /* See if we stopped at the special breakpoint for
- stepping over a subroutine call. If both are zero,
- this wasn't the reason for the stop. */
- if (step_resume_break_address
- && stop_pc - DECR_PC_AFTER_BREAK
- == step_resume_break_address)
- {
- stop_step_resume_break = 1;
- if (DECR_PC_AFTER_BREAK)
- {
- stop_pc -= DECR_PC_AFTER_BREAK;
- write_register (PC_REGNUM, stop_pc);
- pc_changed = 0;
- }
- }
- else
- {
- stop_bpstat =
- bpstat_stop_status (&stop_pc, stop_frame_address);
- /* Following in case break condition called a
- function. */
- stop_print_frame = 1;
- }
- }
+ ecs->another_trap = 1;
+ keep_going (ecs);
+ return;
}
-
- if (stop_signal == SIGTRAP)
- random_signal
- = !(bpstat_explains_signal (stop_bpstat)
- || trap_expected
- || stop_step_resume_break
- || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
- || (step_range_end && !step_resume_break_address));
- else
+#endif /* 0 */
+ disable_longjmp_breakpoint ();
+ ecs->handling_longjmp = 0; /* FIXME */
+ if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
+ break;
+ /* else fallthrough */
+
+ case BPSTAT_WHAT_SINGLE:
+ if (breakpoints_inserted)
{
- random_signal
- = !(bpstat_explains_signal (stop_bpstat)
- || stop_step_resume_break
- /* End of a stack dummy. Some systems (e.g. Sony
- news) give another signal besides SIGTRAP,
- so check here as well as above. */
- || PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address)
- );
- if (!random_signal)
- stop_signal = SIGTRAP;
+ thread_step_needed = 1;
+ remove_breakpoints ();
}
- }
- else
- random_signal = 1;
-
- /* For the program's own signals, act according to
- the signal handling tables. */
-
- if (random_signal)
- {
- /* Signal not for debugging purposes. */
- int printed = 0;
-
- stopped_by_random_signal = 1;
-
- if (stop_signal >= NSIG
- || signal_print[stop_signal])
+ breakpoints_inserted = 0;
+ ecs->another_trap = 1;
+ /* Still need to check other stuff, at least the case
+ where we are stepping and step out of the right range. */
+ break;
+
+ case BPSTAT_WHAT_STOP_NOISY:
+ stop_print_frame = 1;
+
+ /* We are about to nuke the step_resume_breakpoint and
+ through_sigtramp_breakpoint via the cleanup chain, so
+ no need to worry about it here. */
+
+ stop_stepping (ecs);
+ return;
+
+ case BPSTAT_WHAT_STOP_SILENT:
+ stop_print_frame = 0;
+
+ /* We are about to nuke the step_resume_breakpoint and
+ through_sigtramp_breakpoint via the cleanup chain, so
+ no need to worry about it here. */
+
+ stop_stepping (ecs);
+ return;
+
+ case BPSTAT_WHAT_STEP_RESUME:
+ /* This proably demands a more elegant solution, but, yeah
+ right...
+
+ This function's use of the simple variable
+ step_resume_breakpoint doesn't seem to accomodate
+ simultaneously active step-resume bp's, although the
+ breakpoint list certainly can.
+
+ If we reach here and step_resume_breakpoint is already
+ NULL, then apparently we have multiple active
+ step-resume bp's. We'll just delete the breakpoint we
+ stopped at, and carry on.
+
+ Correction: what the code currently does is delete a
+ step-resume bp, but it makes no effort to ensure that
+ the one deleted is the one currently stopped at. MVS */
+
+ if (step_resume_breakpoint == NULL)
{
- printed = 1;
- target_terminal_ours_for_output ();
-#ifdef PRINT_RANDOM_SIGNAL
- PRINT_RANDOM_SIGNAL (stop_signal);
-#else
- printf_filtered ("\nProgram received signal %d, %s\n",
- stop_signal, safe_strsignal (stop_signal));
-#endif /* PRINT_RANDOM_SIGNAL */
- fflush (stdout);
+ step_resume_breakpoint =
+ bpstat_find_step_resume_breakpoint (stop_bpstat);
}
- if (stop_signal >= NSIG
- || signal_stop[stop_signal])
- break;
- /* If not going to stop, give terminal back
- if we took it away. */
- else if (printed)
- target_terminal_inferior ();
-
- /* Note that virtually all the code below does `if !random_signal'.
- Perhaps this code should end with a goto or continue. At least
- one (now fixed) bug was caused by this -- a !random_signal was
- missing in one of the tests below. */
- }
+ delete_breakpoint (step_resume_breakpoint);
+ step_resume_breakpoint = NULL;
+ break;
- /* Handle cases caused by hitting a breakpoint. */
+ case BPSTAT_WHAT_THROUGH_SIGTRAMP:
+ if (through_sigtramp_breakpoint)
+ delete_breakpoint (through_sigtramp_breakpoint);
+ through_sigtramp_breakpoint = NULL;
+
+ /* If were waiting for a trap, hitting the step_resume_break
+ doesn't count as getting it. */
+ if (trap_expected)
+ ecs->another_trap = 1;
+ break;
- if (!random_signal)
- if (bpstat_explains_signal (stop_bpstat))
+ case BPSTAT_WHAT_CHECK_SHLIBS:
+ case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
+#ifdef SOLIB_ADD
{
- CORE_ADDR jmp_buf_pc;
+ /* Remove breakpoints, we eventually want to step over the
+ shlib event breakpoint, and SOLIB_ADD might adjust
+ breakpoint addresses via breakpoint_re_set. */
+ if (breakpoints_inserted)
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
- switch (stop_bpstat->breakpoint_at->type) /* FIXME */
+ /* Check for any newly added shared libraries if we're
+ supposed to be adding them automatically. */
+ if (auto_solib_add)
{
- /* If we hit the breakpoint at longjmp, disable it for the
- duration of this command. Then, install a temporary
- breakpoint at the target of the jmp_buf. */
- case bp_longjmp:
- disable_longjmp_breakpoint();
- remove_breakpoints ();
- breakpoints_inserted = 0;
- if (!GET_LONGJMP_TARGET(&jmp_buf_pc)) goto keep_going;
-
- /* Need to blow away step-resume breakpoint, as it
- interferes with us */
- remove_step_breakpoint ();
- step_resume_break_address = 0;
- stop_step_resume_break = 0;
-
-#if 0 /* FIXME - Need to implement nested temporary breakpoints */
- if (step_over_calls > 0)
- set_longjmp_resume_breakpoint(jmp_buf_pc,
- get_current_frame());
- else
-#endif /* 0 */
- set_longjmp_resume_breakpoint(jmp_buf_pc, NULL);
- handling_longjmp = 1; /* FIXME */
- goto keep_going;
-
- case bp_longjmp_resume:
- remove_breakpoints ();
- breakpoints_inserted = 0;
-#if 0 /* FIXME - Need to implement nested temporary breakpoints */
- if (step_over_calls
- && (stop_frame_address
- INNER_THAN step_frame_address))
- {
- another_trap = 1;
- goto keep_going;
- }
-#endif /* 0 */
- disable_longjmp_breakpoint();
- handling_longjmp = 0; /* FIXME */
- break;
+ /* Switch terminal for any messages produced by
+ breakpoint_re_set. */
+ target_terminal_ours_for_output ();
+ SOLIB_ADD (NULL, 0, NULL);
+ target_terminal_inferior ();
+ }
- default:
- fprintf(stderr, "Unknown breakpoint type %d\n",
- stop_bpstat->breakpoint_at->type);
- case bp_watchpoint:
- case bp_breakpoint:
- case bp_until:
- case bp_finish:
- /* Does a breakpoint want us to stop? */
- if (bpstat_stop (stop_bpstat))
- {
- stop_print_frame = bpstat_should_print (stop_bpstat);
- goto stop_stepping;
- }
- /* Otherwise, must remove breakpoints and single-step
- to get us past the one we hit. */
- else
- {
- remove_breakpoints ();
- remove_step_breakpoint ();
- breakpoints_inserted = 0;
- another_trap = 1;
- }
+ /* Try to reenable shared library breakpoints, additional
+ code segments in shared libraries might be mapped in now. */
+ re_enable_breakpoints_in_shlibs ();
+
+ /* If requested, stop when the dynamic linker notifies
+ gdb of events. This allows the user to get control
+ and place breakpoints in initializer routines for
+ dynamically loaded objects (among other things). */
+ if (stop_on_solib_events)
+ {
+ stop_print_frame = 0;
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* If we stopped due to an explicit catchpoint, then the
+ (see above) call to SOLIB_ADD pulled in any symbols
+ from a newly-loaded library, if appropriate.
+
+ We do want the inferior to stop, but not where it is
+ now, which is in the dynamic linker callback. Rather,
+ we would like it stop in the user's program, just after
+ the call that caused this catchpoint to trigger. That
+ gives the user a more useful vantage from which to
+ examine their program's state. */
+ else if (what.main_action == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
+ {
+ /* ??rehrauer: If I could figure out how to get the
+ right return PC from here, we could just set a temp
+ breakpoint and resume. I'm not sure we can without
+ cracking open the dld's shared libraries and sniffing
+ their unwind tables and text/data ranges, and that's
+ not a terribly portable notion.
+
+ Until that time, we must step the inferior out of the
+ dld callback, and also out of the dld itself (and any
+ code or stubs in libdld.sl, such as "shl_load" and
+ friends) until we reach non-dld code. At that point,
+ we can stop stepping. */
+ bpstat_get_triggered_catchpoints (stop_bpstat,
+ &ecs->stepping_through_solib_catchpoints);
+ ecs->stepping_through_solib_after_catch = 1;
+
+ /* Be sure to lift all breakpoints, so the inferior does
+ actually step past this point... */
+ ecs->another_trap = 1;
break;
}
- }
- else if (stop_step_resume_break)
- {
- /* But if we have hit the step-resumption breakpoint,
- remove it. It has done its job getting us here.
- The sp test is to make sure that we don't get hung
- up in recursive calls in functions without frame
- pointers. If the stack pointer isn't outside of
- where the breakpoint was set (within a routine to be
- stepped over), we're in the middle of a recursive
- call. Not true for reg window machines (sparc)
- because the must change frames to call things and
- the stack pointer doesn't have to change if it
- the bp was set in a routine without a frame (pc can
- be stored in some other window).
-
- The removal of the sp test is to allow calls to
- alloca. Nasty things were happening. Oh, well,
- gdb can only handle one level deep of lack of
- frame pointer. */
-
- /*
- Disable test for step_frame_address match so that we always stop even if the
- frames don't match. Reason: if we hit the step_resume_breakpoint, there is
- no way to temporarily disable it so that we can step past it. If we leave
- the breakpoint in, then we loop forever repeatedly hitting, but never
- getting past the breakpoint. This change keeps nexting over recursive
- function calls from hanging gdb.
- */
-#if 0
- if (* step_frame_address == 0
- || (step_frame_address == stop_frame_address))
-#endif
+ else
{
- remove_step_breakpoint ();
- step_resume_break_address = 0;
-
- /* If were waiting for a trap, hitting the step_resume_break
- doesn't count as getting it. */
- if (trap_expected)
- another_trap = 1;
+ /* We want to step over this breakpoint, then keep going. */
+ ecs->another_trap = 1;
+ break;
}
}
+#endif
+ break;
- /* We come here if we hit a breakpoint but should not
- stop for it. Possibly we also were stepping
- and should stop for that. So fall through and
- test for stepping. But, if not stepping,
- do not stop. */
+ case BPSTAT_WHAT_LAST:
+ /* Not a real code, but listed here to shut up gcc -Wall. */
- /* If this is the breakpoint at the end of a stack dummy,
- just stop silently. */
- if (!random_signal
- && PC_IN_CALL_DUMMY (stop_pc, stop_sp, stop_frame_address))
+ case BPSTAT_WHAT_KEEP_CHECKING:
+ break;
+ }
+ }
+
+ /* We come here if we hit a breakpoint but should not
+ stop for it. Possibly we also were stepping
+ and should stop for that. So fall through and
+ test for stepping. But, if not stepping,
+ do not stop. */
+
+ /* Are we stepping to get the inferior out of the dynamic
+ linker's hook (and possibly the dld itself) after catching
+ a shlib event? */
+ if (ecs->stepping_through_solib_after_catch)
+ {
+#if defined(SOLIB_ADD)
+ /* Have we reached our destination? If not, keep going. */
+ if (SOLIB_IN_DYNAMIC_LINKER (ecs->pid, stop_pc))
+ {
+ ecs->another_trap = 1;
+ keep_going (ecs);
+ return;
+ }
+#endif
+ /* Else, stop and report the catchpoint(s) whose triggering
+ caused us to begin stepping. */
+ ecs->stepping_through_solib_after_catch = 0;
+ bpstat_clear (&stop_bpstat);
+ stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
+ bpstat_clear (&ecs->stepping_through_solib_catchpoints);
+ stop_print_frame = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
+ {
+ /* This is the old way of detecting the end of the stack dummy.
+ An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
+ handled above. As soon as we can test it on all of them, all
+ architectures should define it. */
+
+ /* If this is the breakpoint at the end of a stack dummy,
+ just stop silently, unless the user was doing an si/ni, in which
+ case she'd better know what she's doing. */
+
+ if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
+ FRAME_FP (get_current_frame ()))
+ && !step_range_end)
{
stop_print_frame = 0;
stop_stack_dummy = 1;
#ifdef HP_OS_BUG
trap_expected_after_continue = 1;
#endif
- break;
+ stop_stepping (ecs);
+ return;
}
-
- if (step_resume_break_address)
+ }
+
+ if (step_resume_breakpoint)
+ {
/* Having a step-resume breakpoint overrides anything
else having to do with stepping commands until
that breakpoint is reached. */
- ;
- /* If stepping through a line, keep going if still within it. */
- else if (!random_signal
- && step_range_end
- && stop_pc >= step_range_start
- && stop_pc < step_range_end
- /* The step range might include the start of the
- function, so if we are at the start of the
- step range and either the stack or frame pointers
- just changed, we've stepped outside */
- && !(stop_pc == step_range_start
- && stop_frame_address
- && (stop_sp INNER_THAN prev_sp
- || stop_frame_address != step_frame_address)))
- {
- ;
- }
-
- /* We stepped out of the stepping range. See if that was due
- to a subroutine call that we should proceed to the end of. */
- else if (!random_signal && step_range_end)
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ if (step_range_end == 0)
+ {
+ /* Likewise if we aren't even stepping. */
+ /* I'm not sure whether this needs to be check_sigtramp2 or
+ whether it could/should be keep_going. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* If stepping through a line, keep going if still within it.
+
+ Note that step_range_end is the address of the first instruction
+ beyond the step range, and NOT the address of the last instruction
+ within it! */
+ if (stop_pc >= step_range_start
+ && stop_pc < step_range_end)
+ {
+ /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
+ So definately need to check for sigtramp here. */
+ check_sigtramp2 (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* We stepped out of the stepping range. */
+
+ /* If we are stepping at the source level and entered the runtime
+ loader dynamic symbol resolution code, we keep on single stepping
+ until we exit the run time loader code and reach the callee's
+ address. */
+ if (step_over_calls < 0 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
+ {
+ CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
+
+ if (pc_after_resolver)
+ {
+ /* Set up a step-resume breakpoint at the address
+ indicated by SKIP_SOLIB_RESOLVER. */
+ struct symtab_and_line sr_sal;
+ INIT_SAL (&sr_sal);
+ sr_sal.pc = pc_after_resolver;
+
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+ }
+
+ keep_going (ecs);
+ return;
+ }
+
+ /* We can't update step_sp every time through the loop, because
+ reading the stack pointer would slow down stepping too much.
+ But we can update it every time we leave the step range. */
+ ecs->update_step_sp = 1;
+
+ /* Did we just take a signal? */
+ if (IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && INNER_THAN (read_sp (), step_sp))
+ {
+ /* We've just taken a signal; go until we are back to
+ the point where we took it and one more. */
+
+ /* Note: The test above succeeds not only when we stepped
+ into a signal handler, but also when we step past the last
+ statement of a signal handler and end up in the return stub
+ of the signal handler trampoline. To distinguish between
+ these two cases, check that the frame is INNER_THAN the
+ previous one below. pai/1997-09-11 */
+
+
{
- if (stop_func_start)
- {
- prologue_pc = stop_func_start;
- SKIP_PROLOGUE (prologue_pc);
- }
+ CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
- /* Did we just take a signal? */
- if (IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
+ if (INNER_THAN (current_frame, step_frame_address))
{
+ /* We have just taken a signal; go until we are back to
+ the point where we took it and one more. */
+
/* This code is needed at least in the following case:
- The user types "next" and then a signal arrives (before
- the "next" is done). */
- /* We've just taken a signal; go until we are back to
- the point where we took it and one more. */
- step_resume_break_address = prev_pc;
- step_resume_break_duplicate =
- breakpoint_here_p (step_resume_break_address);
+ The user types "next" and then a signal arrives (before
+ the "next" is done). */
+
+ /* Note that if we are stopped at a breakpoint, then we need
+ the step_resume breakpoint to override any breakpoints at
+ the same location, so that we will still step over the
+ breakpoint even though the signal happened. */
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal);
+ sr_sal.symtab = NULL;
+ sr_sal.line = 0;
+ sr_sal.pc = prev_pc;
+ /* We could probably be setting the frame to
+ step_frame_address; I don't think anyone thought to
+ try it. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
if (breakpoints_inserted)
- insert_step_breakpoint ();
- /* Make sure that the stepping range gets us past
- that instruction. */
- if (step_range_end == 1)
- step_range_end = (step_range_start = prev_pc) + 1;
- remove_breakpoints_on_following_step = 1;
- goto save_pc;
+ insert_breakpoints ();
+ }
+ else
+ {
+ /* We just stepped out of a signal handler and into
+ its calling trampoline.
+
+ Normally, we'd call step_over_function from
+ here, but for some reason GDB can't unwind the
+ stack correctly to find the real PC for the point
+ user code where the signal trampoline will return
+ -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
+ But signal trampolines are pretty small stubs of
+ code, anyway, so it's OK instead to just
+ single-step out. Note: assuming such trampolines
+ don't exhibit recursion on any platform... */
+ find_pc_partial_function (stop_pc, &ecs->stop_func_name,
+ &ecs->stop_func_start,
+ &ecs->stop_func_end);
+ /* Readjust stepping range */
+ step_range_start = ecs->stop_func_start;
+ step_range_end = ecs->stop_func_end;
+ ecs->stepping_through_sigtramp = 1;
}
+ }
+
+
+ /* If this is stepi or nexti, make sure that the stepping range
+ gets us past that instruction. */
+ if (step_range_end == 1)
+ /* FIXME: Does this run afoul of the code below which, if
+ we step into the middle of a line, resets the stepping
+ range? */
+ step_range_end = (step_range_start = prev_pc) + 1;
+
+ ecs->remove_breakpoints_on_following_step = 1;
+ keep_going (ecs);
+ return;
+ }
+
+ if (stop_pc == ecs->stop_func_start /* Quick test */
+ || (in_prologue (stop_pc, ecs->stop_func_start) &&
+ !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
+ || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
+ || ecs->stop_func_name == 0)
+ {
+ /* It's a subroutine call. */
- /* ==> See comments at top of file on this algorithm. <==*/
-
- if ((stop_pc == stop_func_start
- || IN_SOLIB_TRAMPOLINE (stop_pc, stop_func_name))
- && (stop_func_start != prev_func_start
- || prologue_pc != stop_func_start
- || stop_sp != prev_sp))
+ if (step_over_calls == 0)
+ {
+ /* I presume that step_over_calls is only 0 when we're
+ supposed to be stepping at the assembly language level
+ ("stepi"). Just stop. */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ if (step_over_calls > 0 || IGNORE_HELPER_CALL (stop_pc))
+ {
+ /* We're doing a "next". */
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
+ }
+
+ /* If we are in a function call trampoline (a stub between
+ the calling routine and the real function), locate the real
+ function. That's what tells us (a) whether we want to step
+ into it at all, and (b) what prologue we want to run to
+ the end of, if we do step into it. */
+ tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+ if (tmp != 0)
+ ecs->stop_func_start = tmp;
+ else
+ {
+ tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
+ if (tmp)
+ {
+ struct symtab_and_line xxx;
+ /* Why isn't this s_a_l called "sr_sal", like all of the
+ other s_a_l's where this code is duplicated? */
+ INIT_SAL (&xxx); /* initialize to zeroes */
+ xxx.pc = tmp;
+ xxx.section = find_pc_overlay (xxx.pc);
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (xxx, NULL, bp_step_resume);
+ insert_breakpoints ();
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ /* If we have line number information for the function we
+ are thinking of stepping into, step into it.
+
+ If there are several symtabs at that PC (e.g. with include
+ files), just want to know whether *any* of them have line
+ numbers. find_pc_line handles this. */
+ {
+ struct symtab_and_line tmp_sal;
+
+ tmp_sal = find_pc_line (ecs->stop_func_start, 0);
+ if (tmp_sal.line != 0)
{
- /* It's a subroutine call.
- (0) If we are not stepping over any calls ("stepi"), we
- just stop.
- (1) If we're doing a "next", we want to continue through
- the call ("step over the call").
- (2) If we are in a function-call trampoline (a stub between
- the calling routine and the real function), locate
- the real function and change stop_func_start.
- (3) If we're doing a "step", and there are no debug symbols
- at the target of the call, we want to continue through
- it ("step over the call").
- (4) Otherwise, we want to stop soon, after the function
- prologue ("step into the call"). */
-
- if (step_over_calls == 0)
- {
- /* I presume that step_over_calls is only 0 when we're
- supposed to be stepping at the assembly language level. */
- stop_step = 1;
- break;
- }
+ step_into_function (ecs);
+ return;
+ }
+ }
+ step_over_function (ecs);
+ keep_going (ecs);
+ return;
- if (step_over_calls > 0)
- goto step_over_function;
+ }
- tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
- if (tmp != 0)
- stop_func_start = tmp;
+ /* We've wandered out of the step range. */
- if (find_pc_function (stop_func_start) != 0)
- goto step_into_function;
+ ecs->sal = find_pc_line (stop_pc, 0);
-step_over_function:
- /* A subroutine call has happened. */
- /* Set a special breakpoint after the return */
- step_resume_break_address =
- ADDR_BITS_REMOVE
- (SAVED_PC_AFTER_CALL (get_current_frame ()));
- step_resume_break_duplicate
- = breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- goto save_pc;
-
-step_into_function:
- /* Subroutine call with source code we should not step over.
- Do step to the first line of code in it. */
- SKIP_PROLOGUE (stop_func_start);
- sal = find_pc_line (stop_func_start, 0);
- /* Use the step_resume_break to step until
- the end of the prologue, even if that involves jumps
- (as it seems to on the vax under 4.2). */
- /* If the prologue ends in the middle of a source line,
- continue to the end of that source line.
- Otherwise, just go to end of prologue. */
+ if (step_range_end == 1)
+ {
+ /* It is stepi or nexti. We always want to stop stepping after
+ one instruction. */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* If we're in the return path from a shared library trampoline,
+ we want to proceed through the trampoline when stepping. */
+ if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
+ {
+ CORE_ADDR tmp;
+
+ /* Determine where this trampoline returns. */
+ tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
+
+ /* Only proceed through if we know where it's going. */
+ if (tmp)
+ {
+ /* And put the step-breakpoint there and go until there. */
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = tmp;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
+ /* Do not specify what the fp should be when we stop
+ since on some machines the prologue
+ is where the new fp value is established. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ /* Restart without fiddling with the step ranges or
+ other state. */
+ keep_going (ecs);
+ return;
+ }
+ }
+
+ if (ecs->sal.line == 0)
+ {
+ /* We have no line number information. That means to stop
+ stepping (does this always happen right after one instruction,
+ when we do "s" in a function with no line numbers,
+ or can this happen as a result of a return or longjmp?). */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ if ((stop_pc == ecs->sal.pc)
+ && (ecs->current_line != ecs->sal.line || ecs->current_symtab != ecs->sal.symtab))
+ {
+ /* We are at the start of a different line. So stop. Note that
+ we don't stop if we step into the middle of a different line.
+ That is said to make things like for (;;) statements work
+ better. */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+
+ /* We aren't done stepping.
+
+ Optimize by setting the stepping range to the line.
+ (We might not be in the original line, but if we entered a
+ new line in mid-statement, we continue stepping. This makes
+ things like for(;;) statements work better.) */
+
+ if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
+ {
+ /* If this is the last line of the function, don't keep stepping
+ (it would probably step us out of the function).
+ This is particularly necessary for a one-line function,
+ in which after skipping the prologue we better stop even though
+ we will be in mid-line. */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+ step_range_start = ecs->sal.pc;
+ step_range_end = ecs->sal.end;
+ step_frame_address = FRAME_FP (get_current_frame ());
+ ecs->current_line = ecs->sal.line;
+ ecs->current_symtab = ecs->sal.symtab;
+
+ /* In the case where we just stepped out of a function into the middle
+ of a line of the caller, continue stepping, but step_frame_address
+ must be modified to current frame */
+ {
+ CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
+ if (!(INNER_THAN (current_frame, step_frame_address)))
+ step_frame_address = current_frame;
+ }
+
+ keep_going (ecs);
+
+ } /* extra brace, to preserve old indentation */
+}
+
+/* Are we in the middle of stepping? */
+
+static int
+currently_stepping (struct execution_control_state *ecs)
+{
+ return ((through_sigtramp_breakpoint == NULL
+ && !ecs->handling_longjmp
+ && ((step_range_end && step_resume_breakpoint == NULL)
+ || trap_expected))
+ || ecs->stepping_through_solib_after_catch
+ || bpstat_should_step ());
+}
+
+static void
+check_sigtramp2 (struct execution_control_state *ecs)
+{
+ if (trap_expected
+ && IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
+ && !IN_SIGTRAMP (prev_pc, prev_func_name)
+ && INNER_THAN (read_sp (), step_sp))
+ {
+ /* What has happened here is that we have just stepped the
+ inferior with a signal (because it is a signal which
+ shouldn't make us stop), thus stepping into sigtramp.
+
+ So we need to set a step_resume_break_address breakpoint and
+ continue until we hit it, and then step. FIXME: This should
+ be more enduring than a step_resume breakpoint; we should
+ know that we will later need to keep going rather than
+ re-hitting the breakpoint here (see the testsuite,
+ gdb.base/signals.exp where it says "exceedingly difficult"). */
+
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = prev_pc;
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
+ /* We perhaps could set the frame if we kept track of what the
+ frame corresponding to prev_pc was. But we don't, so don't. */
+ through_sigtramp_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ ecs->remove_breakpoints_on_following_step = 1;
+ ecs->another_trap = 1;
+ }
+}
+
+/* Subroutine call with source code we should not step over. Do step
+ to the first line of code in it. */
+
+static void
+step_into_function (struct execution_control_state *ecs)
+{
+ struct symtab *s;
+ struct symtab_and_line sr_sal;
+
+ s = find_pc_symtab (stop_pc);
+ if (s && s->language != language_asm)
+ ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
+
+ ecs->sal = find_pc_line (ecs->stop_func_start, 0);
+ /* Use the step_resume_break to step until the end of the prologue,
+ even if that involves jumps (as it seems to on the vax under
+ 4.2). */
+ /* If the prologue ends in the middle of a source line, continue to
+ the end of that source line (if it is still within the function).
+ Otherwise, just go to end of prologue. */
#ifdef PROLOGUE_FIRSTLINE_OVERLAP
- /* no, don't either. It skips any code that's
- legitimately on the first line. */
+ /* no, don't either. It skips any code that's legitimately on the
+ first line. */
#else
- if (sal.end && sal.pc != stop_func_start)
- stop_func_start = sal.end;
+ if (ecs->sal.end
+ && ecs->sal.pc != ecs->stop_func_start
+ && ecs->sal.end < ecs->stop_func_end)
+ ecs->stop_func_start = ecs->sal.end;
#endif
- if (stop_func_start == stop_pc)
- {
- /* We are already there: stop now. */
- stop_step = 1;
- break;
- }
- else
- /* Put the step-breakpoint there and go until there. */
- {
- step_resume_break_address = stop_func_start;
-
- step_resume_break_duplicate
- = breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- /* Do not specify what the fp should be when we stop
- since on some machines the prologue
- is where the new fp value is established. */
- step_frame_address = 0;
- /* And make sure stepping stops right away then. */
- step_range_end = step_range_start;
- }
- goto save_pc;
- }
+ if (ecs->stop_func_start == stop_pc)
+ {
+ /* We are already there: stop now. */
+ stop_step = 1;
+ stop_stepping (ecs);
+ return;
+ }
+ else
+ {
+ /* Put the step-breakpoint there and go until there. */
+ INIT_SAL (&sr_sal); /* initialize to zeroes */
+ sr_sal.pc = ecs->stop_func_start;
+ sr_sal.section = find_pc_overlay (ecs->stop_func_start);
+ /* Do not specify what the fp should be when we stop since on
+ some machines the prologue is where the new fp value is
+ established. */
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+
+ /* And make sure stepping stops right away then. */
+ step_range_end = step_range_start;
+ }
+ keep_going (ecs);
+}
- /* We've wandered out of the step range (but haven't done a
- subroutine call or return). */
+/* We've just entered a callee, and we wish to resume until it returns
+ to the caller. Setting a step_resume breakpoint on the return
+ address will catch a return from the callee.
+
+ However, if the callee is recursing, we want to be careful not to
+ catch returns of those recursive calls, but only of THIS instance
+ of the call.
- sal = find_pc_line(stop_pc, 0);
-
- if (step_range_end == 1 || /* stepi or nexti */
- sal.line == 0 || /* ...or no line # info */
- (stop_pc == sal.pc /* ...or we're at the start */
- && current_line != sal.line)) { /* of a different line */
- /* Stop because we're done stepping. */
- stop_step = 1;
- break;
- } else {
- /* We aren't done stepping, and we have line number info for $pc.
- Optimize by setting the step_range for the line.
- (We might not be in the original line, but if we entered a
- new line in mid-statement, we continue stepping. This makes
- things like for(;;) statements work better.) */
- step_range_start = sal.pc;
- step_range_end = sal.end;
- goto save_pc;
- }
- /* We never fall through here */
- }
+ To do this, we set the step_resume bp's frame to our current
+ caller's frame (step_frame_address, which is set by the "next" or
+ "until" command, before execution begins). */
+
+static void
+step_over_function (struct execution_control_state *ecs)
+{
+ struct symtab_and_line sr_sal;
+
+ INIT_SAL (&sr_sal); /* initialize to zeros */
+ sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
+ sr_sal.section = find_pc_overlay (sr_sal.pc);
+
+ check_for_old_step_resume_breakpoint ();
+ step_resume_breakpoint =
+ set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
- if (trap_expected
- && IN_SIGTRAMP (stop_pc, stop_func_name)
- && !IN_SIGTRAMP (prev_pc, prev_func_name))
+ if (!IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
+ step_resume_breakpoint->frame = step_frame_address;
+
+ if (breakpoints_inserted)
+ insert_breakpoints ();
+}
+
+static void
+stop_stepping (struct execution_control_state *ecs)
+{
+ if (target_has_execution)
+ {
+ /* Are we stopping for a vfork event? We only stop when we see
+ the child's event. However, we may not yet have seen the
+ parent's event. And, inferior_pid is still set to the
+ parent's pid, until we resume again and follow either the
+ parent or child.
+
+ To ensure that we can really touch inferior_pid (aka, the
+ parent process) -- which calls to functions like read_pc
+ implicitly do -- wait on the parent if necessary. */
+ if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ && !pending_follow.fork_event.saw_parent_fork)
{
- /* What has happened here is that we have just stepped the inferior
- with a signal (because it is a signal which shouldn't make
- us stop), thus stepping into sigtramp.
-
- So we need to set a step_resume_break_address breakpoint
- and continue until we hit it, and then step. */
- step_resume_break_address = prev_pc;
- /* Always 1, I think, but it's probably easier to have
- the step_resume_break as usual rather than trying to
- re-use the breakpoint which is already there. */
- step_resume_break_duplicate =
- breakpoint_here_p (step_resume_break_address);
- if (breakpoints_inserted)
- insert_step_breakpoint ();
- remove_breakpoints_on_following_step = 1;
- another_trap = 1;
- }
+ int parent_pid;
-/* My apologies to the gods of structured programming. */
-/* Come to this label when you need to resume the inferior. It's really much
- cleaner at this time to do a goto than to try and figure out what the
- if-else chain ought to look like!! */
+ do
+ {
+ if (target_wait_hook)
+ parent_pid = target_wait_hook (-1, &(ecs->ws));
+ else
+ parent_pid = target_wait (-1, &(ecs->ws));
+ }
+ while (parent_pid != inferior_pid);
+ }
- keep_going:
+ /* Assuming the inferior still exists, set these up for next
+ time, just like we did above if we didn't break out of the
+ loop. */
+ prev_pc = read_pc ();
+ prev_func_start = ecs->stop_func_start;
+ prev_func_name = ecs->stop_func_name;
+ }
-save_pc:
- /* Save the pc before execution, to compare with pc after stop. */
- prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
- prev_func_start = stop_func_start; /* Ok, since if DECR_PC_AFTER
- BREAK is defined, the
- original pc would not have
- been at the start of a
- function. */
- prev_func_name = stop_func_name;
- prev_sp = stop_sp;
+ /* Let callers know we don't want to wait for the inferior anymore. */
+ ecs->wait_some_more = 0;
+}
- /* If we did not do break;, it means we should keep
- running the inferior and not return to debugger. */
+/* This function handles various cases where we need to continue
+ waiting for the inferior. */
+/* (Used to be the keep_going: label in the old wait_for_inferior) */
- if (trap_expected && stop_signal != SIGTRAP)
+static void
+keep_going (struct execution_control_state *ecs)
+{
+ /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
+ vforked child between its creation and subsequent exit or call to
+ exec(). However, I had big problems in this rather creaky exec
+ engine, getting that to work. The fundamental problem is that
+ I'm trying to debug two processes via an engine that only
+ understands a single process with possibly multiple threads.
+
+ Hence, this spot is known to have problems when
+ target_can_follow_vfork_prior_to_exec returns 1. */
+
+ /* Save the pc before execution, to compare with pc after stop. */
+ prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
+ prev_func_start = ecs->stop_func_start; /* Ok, since if DECR_PC_AFTER
+ BREAK is defined, the
+ original pc would not have
+ been at the start of a
+ function. */
+ prev_func_name = ecs->stop_func_name;
+
+ if (ecs->update_step_sp)
+ step_sp = read_sp ();
+ ecs->update_step_sp = 0;
+
+ /* If we did not do break;, it means we should keep running the
+ inferior and not return to debugger. */
+
+ if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
+ {
+ /* We took a signal (which we are supposed to pass through to
+ the inferior, else we'd have done a break above) and we
+ haven't yet gotten our trap. Simply continue. */
+ resume (currently_stepping (ecs), stop_signal);
+ }
+ else
+ {
+ /* Either the trap was not expected, but we are continuing
+ anyway (the user asked that this signal be passed to the
+ child)
+ -- or --
+ The signal was SIGTRAP, e.g. it was our signal, but we
+ decided we should resume from it.
+
+ We're going to run this baby now!
+
+ Insert breakpoints now, unless we are trying to one-proceed
+ past a breakpoint. */
+ /* If we've just finished a special step resume and we don't
+ want to hit a breakpoint, pull em out. */
+ if (step_resume_breakpoint == NULL
+ && through_sigtramp_breakpoint == NULL
+ && ecs->remove_breakpoints_on_following_step)
{
- /* We took a signal (which we are supposed to pass through to
- the inferior, else we'd have done a break above) and we
- haven't yet gotten our trap. Simply continue. */
- resume ((step_range_end && !step_resume_break_address)
- || (trap_expected && !step_resume_break_address)
- || bpstat_should_step (),
- stop_signal);
+ ecs->remove_breakpoints_on_following_step = 0;
+ remove_breakpoints ();
+ breakpoints_inserted = 0;
}
- else
+ else if (!breakpoints_inserted &&
+ (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
{
- /* Either the trap was not expected, but we are continuing
- anyway (the user asked that this signal be passed to the
- child)
- -- or --
- The signal was SIGTRAP, e.g. it was our signal, but we
- decided we should resume from it.
-
- We're going to run this baby now!
-
- Insert breakpoints now, unless we are trying
- to one-proceed past a breakpoint. */
- /* If we've just finished a special step resume and we don't
- want to hit a breakpoint, pull em out. */
- if (!step_resume_break_address &&
- remove_breakpoints_on_following_step)
- {
- remove_breakpoints_on_following_step = 0;
- remove_breakpoints ();
- breakpoints_inserted = 0;
- }
- else if (!breakpoints_inserted &&
- (step_resume_break_address != 0 || !another_trap))
+ breakpoints_failed = insert_breakpoints ();
+ if (breakpoints_failed)
{
- insert_step_breakpoint ();
- breakpoints_failed = insert_breakpoints ();
- if (breakpoints_failed)
- break;
- breakpoints_inserted = 1;
+ stop_stepping (ecs);
+ return;
}
+ breakpoints_inserted = 1;
+ }
+
+ trap_expected = ecs->another_trap;
+
+ /* Do not deliver SIGNAL_TRAP (except when the user explicitly
+ specifies that such a signal should be delivered to the
+ target program).
- trap_expected = another_trap;
+ Typically, this would occure when a user is debugging a
+ target monitor on a simulator: the target monitor sets a
+ breakpoint; the simulator encounters this break-point and
+ halts the simulation handing control to GDB; GDB, noteing
+ that the break-point isn't valid, returns control back to the
+ simulator; the simulator then delivers the hardware
+ equivalent of a SIGNAL_TRAP to the program being debugged. */
- if (stop_signal == SIGTRAP)
- stop_signal = 0;
+ if (stop_signal == TARGET_SIGNAL_TRAP
+ && !signal_program[stop_signal])
+ stop_signal = TARGET_SIGNAL_0;
#ifdef SHIFT_INST_REGS
- /* I'm not sure when this following segment applies. I do know, now,
- that we shouldn't rewrite the regs when we were stopped by a
- random signal from the inferior process. */
-
- if (!bpstat_explains_signal (stop_bpstat)
- && (stop_signal != SIGCLD)
- && !stopped_by_random_signal)
- {
- CORE_ADDR pc_contents = read_register (PC_REGNUM);
- CORE_ADDR npc_contents = read_register (NPC_REGNUM);
- if (pc_contents != npc_contents)
- {
- write_register (NNPC_REGNUM, npc_contents);
- write_register (NPC_REGNUM, pc_contents);
- }
- }
+ /* I'm not sure when this following segment applies. I do know,
+ now, that we shouldn't rewrite the regs when we were stopped
+ by a random signal from the inferior process. */
+ /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
+ (this is only used on the 88k). */
+
+ if (!bpstat_explains_signal (stop_bpstat)
+ && (stop_signal != TARGET_SIGNAL_CHLD)
+ && !stopped_by_random_signal)
+ SHIFT_INST_REGS ();
#endif /* SHIFT_INST_REGS */
- resume ((!step_resume_break_address
- && !handling_longjmp
- && (step_range_end
- || trap_expected))
- || bpstat_should_step (),
- stop_signal);
- }
+ resume (currently_stepping (ecs), stop_signal);
}
- stop_stepping:
- if (target_has_execution)
+ prepare_to_wait (ecs);
+}
+
+/* This function normally comes after a resume, before
+ handle_inferior_event exits. It takes care of any last bits of
+ housekeeping, and sets the all-important wait_some_more flag. */
+
+static void
+prepare_to_wait (struct execution_control_state *ecs)
+{
+ if (ecs->infwait_state == infwait_normal_state)
{
- /* Assuming the inferior still exists, set these up for next
- time, just like we did above if we didn't break out of the
- loop. */
- prev_pc = read_pc ();
- prev_func_start = stop_func_start;
- prev_func_name = stop_func_name;
- prev_sp = stop_sp;
+ overlay_cache_invalid = 1;
+
+ /* We have to invalidate the registers BEFORE calling
+ target_wait because they can be loaded from the target while
+ in target_wait. This makes remote debugging a bit more
+ efficient for those targets that provide critical registers
+ as part of their normal status mechanism. */
+
+ registers_changed ();
+ ecs->waiton_pid = -1;
+ ecs->wp = &(ecs->ws);
+ }
+ /* This is the old end of the while loop. Let everybody know we
+ want to wait for the inferior some more and get called again
+ soon. */
+ ecs->wait_some_more = 1;
+}
+
+/* This function returns TRUE if ep is an internal breakpoint
+ set to catch generic shared library (aka dynamically-linked
+ library) events. (This is *NOT* the same as a catchpoint for a
+ shlib event. The latter is something a user can set; this is
+ something gdb sets for its own use, and isn't ever shown to a
+ user.) */
+static int
+is_internal_shlib_eventpoint (struct breakpoint *ep)
+{
+ return
+ (ep->type == bp_shlib_event)
+ ;
+}
+
+/* This function returns TRUE if bs indicates that the inferior
+ stopped due to a shared library (aka dynamically-linked library)
+ event. */
+
+static int
+stopped_for_internal_shlib_event (bpstat bs)
+{
+ /* Note that multiple eventpoints may've caused the stop. Any
+ that are associated with shlib events will be accepted. */
+ for (; bs != NULL; bs = bs->next)
+ {
+ if ((bs->breakpoint_at != NULL)
+ && is_internal_shlib_eventpoint (bs->breakpoint_at))
+ return 1;
}
+
+ /* If we get here, then no candidate was found. */
+ return 0;
}
\f
+/* Reset proper settings after an asynchronous command has finished.
+ If the execution command was in synchronous mode, register stdin
+ with the event loop, and reset the prompt. */
+
+static void
+complete_execution (void)
+{
+ target_executing = 0;
+ if (sync_execution)
+ {
+ add_file_handler (input_fd, stdin_event_handler, 0);
+ pop_prompt ();
+ sync_execution = 0;
+ cleanup_sigint_signal_handler ();
+ display_gdb_prompt (0);
+ }
+ else
+ {
+ if (exec_done_display_p)
+ printf_unfiltered ("completed.\n");
+ }
+}
+
/* Here to return control to GDB when the inferior stops for real.
Print appropriate messages, remove breakpoints, give terminal our modes.
attempting to insert breakpoints. */
void
-normal_stop ()
+normal_stop (void)
{
+ /* As with the notification of thread events, we want to delay
+ notifying the user that we've switched thread context until
+ the inferior actually stops.
+
+ (Note that there's no point in saying anything if the inferior
+ has exited!) */
+ if (may_switch_from_inferior_pid
+ && (switched_from_inferior_pid != inferior_pid)
+ && target_has_execution)
+ {
+ target_terminal_ours_for_output ();
+ printf_filtered ("[Switched to %s]\n",
+ target_pid_or_tid_to_str (inferior_pid));
+ switched_from_inferior_pid = inferior_pid;
+ }
+
/* Make sure that the current_frame's pc is correct. This
is a correction for setting up the frame info before doing
DECR_PC_AFTER_BREAK */
- if (target_has_execution)
+ if (target_has_execution && get_current_frame ())
(get_current_frame ())->pc = read_pc ();
-
+
if (breakpoints_failed)
{
target_terminal_ours_for_output ();
The same program may be running in another process.\n");
}
- if (target_has_execution)
- remove_step_breakpoint ();
-
if (target_has_execution && breakpoints_inserted)
- if (remove_breakpoints ())
- {
- target_terminal_ours_for_output ();
- printf_filtered ("Cannot remove breakpoints because program is no longer writable.\n\
-It might be running in another process.\n\
-Further execution is probably impossible.\n");
- }
-
+ {
+ if (remove_breakpoints ())
+ {
+ target_terminal_ours_for_output ();
+ printf_filtered ("Cannot remove breakpoints because ");
+ printf_filtered ("program is no longer writable.\n");
+ printf_filtered ("It might be running in another process.\n");
+ printf_filtered ("Further execution is probably impossible.\n");
+ }
+ }
breakpoints_inserted = 0;
/* Delete the breakpoint we stopped at, if it wants to be deleted.
if (stopped_by_random_signal)
disable_current_display ();
+ /* Don't print a message if in the middle of doing a "step n"
+ operation for n > 1 */
if (step_multi && stop_step)
- return;
+ goto done;
target_terminal_ours ();
+ /* Did we stop because the user set the stop_on_solib_events
+ variable? (If so, we report this as a generic, "Stopped due
+ to shlib event" message.) */
+ if (stopped_for_internal_shlib_event (stop_bpstat))
+ {
+ printf_filtered ("Stopped due to shared library event\n");
+ }
+
+ /* Look up the hook_stop and run it if it exists. */
+
+ if (stop_command && stop_command->hook)
+ {
+ catch_errors (hook_stop_stub, stop_command->hook,
+ "Error while running hook_stop:\n", RETURN_MASK_ALL);
+ }
+
if (!target_has_stack)
- return;
+ {
+
+ goto done;
+ }
+
+ /* Select innermost stack frame - i.e., current frame is frame 0,
+ and current location is based on that.
+ Don't do this on return from a stack dummy routine,
+ or if the program has exited. */
- /* Select innermost stack frame except on return from a stack dummy routine,
- or if the program has exited. Print it without a level number if
- we have changed functions or hit a breakpoint. Print source line
- if we have one. */
if (!stop_stack_dummy)
{
select_frame (get_current_frame (), 0);
+ /* Print current location without a level number, if
+ we have changed functions or hit a breakpoint.
+ Print source line if we have one.
+ bpstat_print() contains the logic deciding in detail
+ what to print, based on the event(s) that just occurred. */
+
if (stop_print_frame)
{
- int source_only;
-
- source_only = bpstat_print (stop_bpstat);
- source_only = source_only ||
- ( stop_step
- && step_frame_address == stop_frame_address
- && step_start_function == find_pc_function (stop_pc));
-
- print_stack_frame (selected_frame, -1, source_only? -1: 1);
+ int bpstat_ret;
+ int source_flag;
+
+ bpstat_ret = bpstat_print (stop_bpstat);
+ /* bpstat_print() returned one of:
+ -1: Didn't print anything
+ 0: Printed preliminary "Breakpoint n, " message, desires
+ location tacked on
+ 1: Printed something, don't tack on location */
+
+ if (bpstat_ret == -1)
+ if (stop_step
+ && step_frame_address == FRAME_FP (get_current_frame ())
+ && step_start_function == find_pc_function (stop_pc))
+ source_flag = -1; /* finished step, just print source line */
+ else
+ source_flag = 1; /* print location and source line */
+ else if (bpstat_ret == 0) /* hit bpt, desire location */
+ source_flag = 1; /* print location and source line */
+ else /* bpstat_ret == 1, hit bpt, do not desire location */
+ source_flag = -1; /* just print source line */
+
+ /* The behavior of this routine with respect to the source
+ flag is:
+ -1: Print only source line
+ 0: Print only location
+ 1: Print location and source line */
+ show_and_print_stack_frame (selected_frame, -1, source_flag);
/* Display the auto-display expressions. */
do_displays ();
{
/* Pop the empty frame that contains the stack dummy.
POP_FRAME ends with a setting of the current frame, so we
- can use that next. */
+ can use that next. */
POP_FRAME;
+ /* Set stop_pc to what it was before we called the function.
+ Can't rely on restore_inferior_status because that only gets
+ called if we don't stop in the called function. */
+ stop_pc = read_pc ();
select_frame (get_current_frame (), 0);
}
+
+
+ TUIDO (((TuiOpaqueFuncPtr) tui_vCheckDataValues, selected_frame));
+
+done:
+ annotate_stopped ();
+}
+
+static int
+hook_stop_stub (void *cmd)
+{
+ execute_user_command ((struct cmd_list_element *) cmd, 0);
+ return (0);
}
\f
-static void
-insert_step_breakpoint ()
+int
+signal_stop_state (int signo)
{
- if (step_resume_break_address && !step_resume_break_duplicate)
- target_insert_breakpoint (step_resume_break_address,
- step_resume_break_shadow);
+ return signal_stop[signo];
}
-static void
-remove_step_breakpoint ()
+int
+signal_print_state (int signo)
{
- if (step_resume_break_address && !step_resume_break_duplicate)
- target_remove_breakpoint (step_resume_break_address,
- step_resume_break_shadow);
+ return signal_print[signo];
}
-\f
-int signal_stop_state (signo)
+
+int
+signal_pass_state (int signo)
+{
+ return signal_program[signo];
+}
+
+int signal_stop_update (signo, state)
int signo;
+ int state;
{
- return ((signo >= 0 && signo < NSIG) ? signal_stop[signo] : 0);
+ int ret = signal_stop[signo];
+ signal_stop[signo] = state;
+ return ret;
}
-int signal_print_state (signo)
+int signal_print_update (signo, state)
int signo;
+ int state;
{
- return ((signo >= 0 && signo < NSIG) ? signal_print[signo] : 0);
+ int ret = signal_print[signo];
+ signal_print[signo] = state;
+ return ret;
}
-int signal_pass_state (signo)
+int signal_pass_update (signo, state)
int signo;
+ int state;
{
- return ((signo >= 0 && signo < NSIG) ? signal_program[signo] : 0);
+ int ret = signal_program[signo];
+ signal_program[signo] = state;
+ return ret;
}
static void
-sig_print_header ()
+sig_print_header (void)
{
- printf_filtered ("Signal\t\tStop\tPrint\tPass to program\tDescription\n");
+ printf_filtered ("\
+Signal Stop\tPrint\tPass to program\tDescription\n");
}
static void
-sig_print_info (number)
- int number;
+sig_print_info (enum target_signal oursig)
{
- char *name;
-
- if ((name = strsigno (number)) == NULL)
- printf_filtered ("%d\t\t", number);
- else
- printf_filtered ("%s (%d)\t", name, number);
- printf_filtered ("%s\t", signal_stop[number] ? "Yes" : "No");
- printf_filtered ("%s\t", signal_print[number] ? "Yes" : "No");
- printf_filtered ("%s\t\t", signal_program[number] ? "Yes" : "No");
- printf_filtered ("%s\n", safe_strsignal (number));
+ char *name = target_signal_to_name (oursig);
+ int name_padding = 13 - strlen (name);
+
+ if (name_padding <= 0)
+ name_padding = 0;
+
+ printf_filtered ("%s", name);
+ printf_filtered ("%*.*s ", name_padding, name_padding,
+ " ");
+ printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
+ printf_filtered ("%s\n", target_signal_to_string (oursig));
}
/* Specify how various signals in the inferior should be handled. */
static void
-handle_command (args, from_tty)
- char *args;
- int from_tty;
+handle_command (char *args, int from_tty)
{
- register char *p = args;
- int signum = 0;
- register int digits, wordlen;
- char *nextarg;
+ char **argv;
+ int digits, wordlen;
+ int sigfirst, signum, siglast;
+ enum target_signal oursig;
+ int allsigs;
+ int nsigs;
+ unsigned char *sigs;
+ struct cleanup *old_chain;
+
+ if (args == NULL)
+ {
+ error_no_arg ("signal to handle");
+ }
+
+ /* Allocate and zero an array of flags for which signals to handle. */
+
+ nsigs = (int) TARGET_SIGNAL_LAST;
+ sigs = (unsigned char *) alloca (nsigs);
+ memset (sigs, 0, nsigs);
- if (!args)
- error_no_arg ("signal to handle");
+ /* Break the command line up into args. */
- while (*p)
+ argv = buildargv (args);
+ if (argv == NULL)
{
- /* Find the end of the next word in the args. */
- for (wordlen = 0;
- p[wordlen] && p[wordlen] != ' ' && p[wordlen] != '\t';
- wordlen++);
- /* Set nextarg to the start of the word after the one we just
- found, and null-terminate this one. */
- if (p[wordlen] == '\0')
- nextarg = p + wordlen;
- else
- {
- p[wordlen] = '\0';
- nextarg = p + wordlen + 1;
- }
-
+ nomem (0);
+ }
+ old_chain = make_cleanup_freeargv (argv);
- for (digits = 0; p[digits] >= '0' && p[digits] <= '9'; digits++);
+ /* Walk through the args, looking for signal oursigs, signal names, and
+ actions. Signal numbers and signal names may be interspersed with
+ actions, with the actions being performed for all signals cumulatively
+ specified. Signal ranges can be specified as <LOW>-<HIGH>. */
- if (signum == 0)
+ while (*argv != NULL)
+ {
+ wordlen = strlen (*argv);
+ for (digits = 0; isdigit ((*argv)[digits]); digits++)
+ {;
+ }
+ allsigs = 0;
+ sigfirst = siglast = -1;
+
+ if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
{
- /* It is the first argument--must be the signal to operate on. */
- if (digits == wordlen)
- {
- /* Numeric. */
- signum = atoi (p);
- if (signum <= 0 || signum > signo_max ())
- {
- p[wordlen] = '\0';
- error ("Invalid signal %s given as argument to \"handle\".", p);
- }
- }
- else
+ /* Apply action to all signals except those used by the
+ debugger. Silently skip those. */
+ allsigs = 1;
+ sigfirst = 0;
+ siglast = nsigs - 1;
+ }
+ else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_stop);
+ SET_SIGS (nsigs, sigs, signal_print);
+ }
+ else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_print);
+ }
+ else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_stop);
+ }
+ else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
+ {
+ SET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_print);
+ UNSET_SIGS (nsigs, sigs, signal_stop);
+ }
+ else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
+ {
+ UNSET_SIGS (nsigs, sigs, signal_program);
+ }
+ else if (digits > 0)
+ {
+ /* It is numeric. The numeric signal refers to our own
+ internal signal numbering from target.h, not to host/target
+ signal number. This is a feature; users really should be
+ using symbolic names anyway, and the common ones like
+ SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
+
+ sigfirst = siglast = (int)
+ target_signal_from_command (atoi (*argv));
+ if ((*argv)[digits] == '-')
{
- /* Symbolic. */
- signum = strtosigno (p);
- if (signum == 0)
- error ("No such signal \"%s\"", p);
+ siglast = (int)
+ target_signal_from_command (atoi ((*argv) + digits + 1));
}
-
- if (signum == SIGTRAP || signum == SIGINT)
+ if (sigfirst > siglast)
{
- if (!query ("%s is used by the debugger.\nAre you sure you want to change it? ", strsigno (signum)))
- error ("Not confirmed.");
+ /* Bet he didn't figure we'd think of this case... */
+ signum = sigfirst;
+ sigfirst = siglast;
+ siglast = signum;
}
}
- /* Else, if already got a signal number, look for flag words
- saying what to do for it. */
- else if (!strncmp (p, "stop", wordlen))
- {
- signal_stop[signum] = 1;
- signal_print[signum] = 1;
- }
- else if (wordlen >= 2 && !strncmp (p, "print", wordlen))
- signal_print[signum] = 1;
- else if (wordlen >= 2 && !strncmp (p, "pass", wordlen))
- signal_program[signum] = 1;
- else if (!strncmp (p, "ignore", wordlen))
- signal_program[signum] = 0;
- else if (wordlen >= 3 && !strncmp (p, "nostop", wordlen))
- signal_stop[signum] = 0;
- else if (wordlen >= 4 && !strncmp (p, "noprint", wordlen))
+ else
{
- signal_print[signum] = 0;
- signal_stop[signum] = 0;
+ oursig = target_signal_from_name (*argv);
+ if (oursig != TARGET_SIGNAL_UNKNOWN)
+ {
+ sigfirst = siglast = (int) oursig;
+ }
+ else
+ {
+ /* Not a number and not a recognized flag word => complain. */
+ error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
+ }
}
- else if (wordlen >= 4 && !strncmp (p, "nopass", wordlen))
- signal_program[signum] = 0;
- else if (wordlen >= 3 && !strncmp (p, "noignore", wordlen))
- signal_program[signum] = 1;
- /* Not a number and not a recognized flag word => complain. */
- else
+
+ /* If any signal numbers or symbol names were found, set flags for
+ which signals to apply actions to. */
+
+ for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
{
- error ("Unrecognized or ambiguous flag word: \"%s\".", p);
+ switch ((enum target_signal) signum)
+ {
+ case TARGET_SIGNAL_TRAP:
+ case TARGET_SIGNAL_INT:
+ if (!allsigs && !sigs[signum])
+ {
+ if (query ("%s is used by the debugger.\n\
+Are you sure you want to change it? ",
+ target_signal_to_name
+ ((enum target_signal) signum)))
+ {
+ sigs[signum] = 1;
+ }
+ else
+ {
+ printf_unfiltered ("Not confirmed, unchanged.\n");
+ gdb_flush (gdb_stdout);
+ }
+ }
+ break;
+ case TARGET_SIGNAL_0:
+ case TARGET_SIGNAL_DEFAULT:
+ case TARGET_SIGNAL_UNKNOWN:
+ /* Make sure that "all" doesn't print these. */
+ break;
+ default:
+ sigs[signum] = 1;
+ break;
+ }
}
- /* Find start of next word. */
- p = nextarg;
- while (*p == ' ' || *p == '\t') p++;
+ argv++;
}
- NOTICE_SIGNAL_HANDLING_CHANGE;
+ target_notice_signals (inferior_pid);
if (from_tty)
{
/* Show the results. */
sig_print_header ();
- sig_print_info (signum);
+ for (signum = 0; signum < nsigs; signum++)
+ {
+ if (sigs[signum])
+ {
+ sig_print_info (signum);
+ }
+ }
+ }
+
+ do_cleanups (old_chain);
+}
+
+static void
+xdb_handle_command (char *args, int from_tty)
+{
+ char **argv;
+ struct cleanup *old_chain;
+
+ /* Break the command line up into args. */
+
+ argv = buildargv (args);
+ if (argv == NULL)
+ {
+ nomem (0);
+ }
+ old_chain = make_cleanup_freeargv (argv);
+ if (argv[1] != (char *) NULL)
+ {
+ char *argBuf;
+ int bufLen;
+
+ bufLen = strlen (argv[0]) + 20;
+ argBuf = (char *) xmalloc (bufLen);
+ if (argBuf)
+ {
+ int validFlag = 1;
+ enum target_signal oursig;
+
+ oursig = target_signal_from_name (argv[0]);
+ memset (argBuf, 0, bufLen);
+ if (strcmp (argv[1], "Q") == 0)
+ sprintf (argBuf, "%s %s", argv[0], "noprint");
+ else
+ {
+ if (strcmp (argv[1], "s") == 0)
+ {
+ if (!signal_stop[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "stop");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "nostop");
+ }
+ else if (strcmp (argv[1], "i") == 0)
+ {
+ if (!signal_program[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "pass");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "nopass");
+ }
+ else if (strcmp (argv[1], "r") == 0)
+ {
+ if (!signal_print[oursig])
+ sprintf (argBuf, "%s %s", argv[0], "print");
+ else
+ sprintf (argBuf, "%s %s", argv[0], "noprint");
+ }
+ else
+ validFlag = 0;
+ }
+ if (validFlag)
+ handle_command (argBuf, from_tty);
+ else
+ printf_filtered ("Invalid signal handling flag.\n");
+ if (argBuf)
+ free (argBuf);
+ }
}
+ do_cleanups (old_chain);
}
-/* Print current contents of the tables set by the handle command. */
+/* Print current contents of the tables set by the handle command.
+ It is possible we should just be printing signals actually used
+ by the current target (but for things to work right when switching
+ targets, all signals should be in the signal tables). */
static void
-signals_info (signum_exp, from_tty)
- char *signum_exp;
- int from_tty;
+signals_info (char *signum_exp, int from_tty)
{
- register int i;
+ enum target_signal oursig;
sig_print_header ();
if (signum_exp)
{
/* First see if this is a symbol name. */
- i = strtosigno (signum_exp);
- if (i == 0)
+ oursig = target_signal_from_name (signum_exp);
+ if (oursig == TARGET_SIGNAL_UNKNOWN)
{
- /* Nope, maybe it's an address which evaluates to a signal
- number. */
- i = parse_and_eval_address (signum_exp);
- if (i >= NSIG || i < 0)
- error ("Signal number out of bounds.");
+ /* No, try numeric. */
+ oursig =
+ target_signal_from_command (parse_and_eval_address (signum_exp));
}
- sig_print_info (i);
+ sig_print_info (oursig);
return;
}
printf_filtered ("\n");
- for (i = 0; i < NSIG; i++)
+ /* These ugly casts brought to you by the native VAX compiler. */
+ for (oursig = TARGET_SIGNAL_FIRST;
+ (int) oursig < (int) TARGET_SIGNAL_LAST;
+ oursig = (enum target_signal) ((int) oursig + 1))
{
QUIT;
- sig_print_info (i);
+ if (oursig != TARGET_SIGNAL_UNKNOWN
+ && oursig != TARGET_SIGNAL_DEFAULT
+ && oursig != TARGET_SIGNAL_0)
+ sig_print_info (oursig);
}
printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
}
\f
+struct inferior_status
+{
+ enum target_signal stop_signal;
+ CORE_ADDR stop_pc;
+ bpstat stop_bpstat;
+ int stop_step;
+ int stop_stack_dummy;
+ int stopped_by_random_signal;
+ int trap_expected;
+ CORE_ADDR step_range_start;
+ CORE_ADDR step_range_end;
+ CORE_ADDR step_frame_address;
+ int step_over_calls;
+ CORE_ADDR step_resume_break_address;
+ int stop_after_trap;
+ int stop_soon_quietly;
+ CORE_ADDR selected_frame_address;
+ char *stop_registers;
+
+ /* These are here because if call_function_by_hand has written some
+ registers and then decides to call error(), we better not have changed
+ any registers. */
+ char *registers;
+
+ int selected_level;
+ int breakpoint_proceeded;
+ int restore_stack_info;
+ int proceed_to_finish;
+};
+
+static struct inferior_status *
+xmalloc_inferior_status (void)
+{
+ struct inferior_status *inf_status;
+ inf_status = xmalloc (sizeof (struct inferior_status));
+ inf_status->stop_registers = xmalloc (REGISTER_BYTES);
+ inf_status->registers = xmalloc (REGISTER_BYTES);
+ return inf_status;
+}
+
+static void
+free_inferior_status (struct inferior_status *inf_status)
+{
+ free (inf_status->registers);
+ free (inf_status->stop_registers);
+ free (inf_status);
+}
+
+void
+write_inferior_status_register (struct inferior_status *inf_status, int regno,
+ LONGEST val)
+{
+ int size = REGISTER_RAW_SIZE (regno);
+ void *buf = alloca (size);
+ store_signed_integer (buf, size, val);
+ memcpy (&inf_status->registers[REGISTER_BYTE (regno)], buf, size);
+}
+
/* Save all of the information associated with the inferior<==>gdb
connection. INF_STATUS is a pointer to a "struct inferior_status"
(defined in inferior.h). */
-void
-save_inferior_status (inf_status, restore_stack_info)
- struct inferior_status *inf_status;
- int restore_stack_info;
+struct inferior_status *
+save_inferior_status (int restore_stack_info)
{
- inf_status->pc_changed = pc_changed;
+ struct inferior_status *inf_status = xmalloc_inferior_status ();
+
inf_status->stop_signal = stop_signal;
inf_status->stop_pc = stop_pc;
- inf_status->stop_frame_address = stop_frame_address;
inf_status->stop_step = stop_step;
inf_status->stop_stack_dummy = stop_stack_dummy;
inf_status->stopped_by_random_signal = stopped_by_random_signal;
inf_status->step_range_end = step_range_end;
inf_status->step_frame_address = step_frame_address;
inf_status->step_over_calls = step_over_calls;
- inf_status->step_resume_break_address = step_resume_break_address;
inf_status->stop_after_trap = stop_after_trap;
inf_status->stop_soon_quietly = stop_soon_quietly;
- /* Save original bpstat chain here; replace it with copy of chain.
+ /* Save original bpstat chain here; replace it with copy of chain.
If caller's caller is walking the chain, they'll be happier if we
- hand them back the original chain when restore_i_s is called. */
+ hand them back the original chain when restore_inferior_status is
+ called. */
inf_status->stop_bpstat = stop_bpstat;
stop_bpstat = bpstat_copy (stop_bpstat);
inf_status->breakpoint_proceeded = breakpoint_proceeded;
inf_status->restore_stack_info = restore_stack_info;
inf_status->proceed_to_finish = proceed_to_finish;
-
- bcopy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
-
+
+ memcpy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
+
+ read_register_bytes (0, inf_status->registers, REGISTER_BYTES);
+
record_selected_frame (&(inf_status->selected_frame_address),
&(inf_status->selected_level));
- return;
+ return inf_status;
}
-void
-restore_inferior_status (inf_status)
- struct inferior_status *inf_status;
+struct restore_selected_frame_args
+{
+ CORE_ADDR frame_address;
+ int level;
+};
+
+static int
+restore_selected_frame (void *args)
{
- FRAME fid;
- int level = inf_status->selected_level;
+ struct restore_selected_frame_args *fr =
+ (struct restore_selected_frame_args *) args;
+ struct frame_info *frame;
+ int level = fr->level;
+
+ frame = find_relative_frame (get_current_frame (), &level);
+
+ /* If inf_status->selected_frame_address is NULL, there was no
+ previously selected frame. */
+ if (frame == NULL ||
+ /* FRAME_FP (frame) != fr->frame_address || */
+ /* elz: deleted this check as a quick fix to the problem that
+ for function called by hand gdb creates no internal frame
+ structure and the real stack and gdb's idea of stack are
+ different if nested calls by hands are made.
+
+ mvs: this worries me. */
+ level != 0)
+ {
+ warning ("Unable to restore previously selected frame.\n");
+ return 0;
+ }
+
+ select_frame (frame, fr->level);
+
+ return (1);
+}
- pc_changed = inf_status->pc_changed;
+void
+restore_inferior_status (struct inferior_status *inf_status)
+{
stop_signal = inf_status->stop_signal;
stop_pc = inf_status->stop_pc;
- stop_frame_address = inf_status->stop_frame_address;
stop_step = inf_status->stop_step;
stop_stack_dummy = inf_status->stop_stack_dummy;
stopped_by_random_signal = inf_status->stopped_by_random_signal;
step_range_end = inf_status->step_range_end;
step_frame_address = inf_status->step_frame_address;
step_over_calls = inf_status->step_over_calls;
- step_resume_break_address = inf_status->step_resume_break_address;
stop_after_trap = inf_status->stop_after_trap;
stop_soon_quietly = inf_status->stop_soon_quietly;
bpstat_clear (&stop_bpstat);
breakpoint_proceeded = inf_status->breakpoint_proceeded;
proceed_to_finish = inf_status->proceed_to_finish;
- bcopy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
+ /* FIXME: Is the restore of stop_registers always needed */
+ memcpy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
/* The inferior can be gone if the user types "print exit(0)"
(and perhaps other times). */
+ if (target_has_execution)
+ write_register_bytes (0, inf_status->registers, REGISTER_BYTES);
+
+ /* FIXME: If we are being called after stopping in a function which
+ is called from gdb, we should not be trying to restore the
+ selected frame; it just prints a spurious error message (The
+ message is useful, however, in detecting bugs in gdb (like if gdb
+ clobbers the stack)). In fact, should we be restoring the
+ inferior status at all in that case? . */
+
if (target_has_stack && inf_status->restore_stack_info)
{
- fid = find_relative_frame (get_current_frame (),
- &level);
-
- /* If inf_status->selected_frame_address is NULL, there was no
- previously selected frame. */
- if (fid == 0 ||
- FRAME_FP (fid) != inf_status->selected_frame_address ||
- level != 0)
- {
-#if 1
- /* I'm not sure this error message is a good idea. I have
- only seen it occur after "Can't continue previously
- requested operation" (we get called from do_cleanups), in
- which case it just adds insult to injury (one confusing
- error message after another. Besides which, does the
- user really care if we can't restore the previously
- selected frame? */
- fprintf (stderr, "Unable to restore previously selected frame.\n");
-#endif
- select_frame (get_current_frame (), 0);
- return;
- }
-
- select_frame (fid, inf_status->selected_level);
+ struct restore_selected_frame_args fr;
+ fr.level = inf_status->selected_level;
+ fr.frame_address = inf_status->selected_frame_address;
+ /* The point of catch_errors is that if the stack is clobbered,
+ walking the stack might encounter a garbage pointer and error()
+ trying to dereference it. */
+ if (catch_errors (restore_selected_frame, &fr,
+ "Unable to restore previously selected frame:\n",
+ RETURN_MASK_ERROR) == 0)
+ /* Error in restoring the selected frame. Select the innermost
+ frame. */
+
+
+ select_frame (get_current_frame (), 0);
+
}
+
+ free_inferior_status (inf_status);
+}
+
+void
+discard_inferior_status (struct inferior_status *inf_status)
+{
+ /* See save_inferior_status for info on stop_bpstat. */
+ bpstat_clear (&inf_status->stop_bpstat);
+ free_inferior_status (inf_status);
}
+static void
+set_follow_fork_mode_command (char *arg, int from_tty,
+ struct cmd_list_element *c)
+{
+ if (!STREQ (arg, "parent") &&
+ !STREQ (arg, "child") &&
+ !STREQ (arg, "both") &&
+ !STREQ (arg, "ask"))
+ error ("follow-fork-mode must be one of \"parent\", \"child\", \"both\" or \"ask\".");
+
+ if (follow_fork_mode_string != NULL)
+ free (follow_fork_mode_string);
+ follow_fork_mode_string = savestring (arg, strlen (arg));
+}
\f
+static void
+build_infrun (void)
+{
+ stop_registers = xmalloc (REGISTER_BYTES);
+}
+
void
-_initialize_infrun ()
+_initialize_infrun (void)
{
register int i;
register int numsigs;
+ struct cmd_list_element *c;
+
+ build_infrun ();
+
+ register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
+ register_gdbarch_swap (NULL, 0, build_infrun);
add_info ("signals", signals_info,
"What debugger does when program gets various signals.\n\
-Specify a signal number as argument to print info on that signal only.");
+Specify a signal as argument to print info on that signal only.");
+ add_info_alias ("handle", "signals", 0);
add_com ("handle", class_run, handle_command,
- "Specify how to handle a signal.\n\
-Args are signal number followed by flags.\n\
-Flags allowed are \"stop\", \"print\", \"pass\",\n\
- \"nostop\", \"noprint\" or \"nopass\".\n\
+ concat ("Specify how to handle a signal.\n\
+Args are signals and actions to apply to those signals.\n\
+Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
+from 1-15 are allowed for compatibility with old versions of GDB.\n\
+Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
+The special arg \"all\" is recognized to mean all signals except those\n\
+used by the debugger, typically SIGTRAP and SIGINT.\n",
+ "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
+\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
+Stop means reenter debugger if this signal happens (implies print).\n\
Print means print a message if this signal happens.\n\
+Pass means let program see this signal; otherwise program doesn't know.\n\
+Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
+Pass and Stop may be combined.", NULL));
+ if (xdb_commands)
+ {
+ add_com ("lz", class_info, signals_info,
+ "What debugger does when program gets various signals.\n\
+Specify a signal as argument to print info on that signal only.");
+ add_com ("z", class_run, xdb_handle_command,
+ concat ("Specify how to handle a signal.\n\
+Args are signals and actions to apply to those signals.\n\
+Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
+from 1-15 are allowed for compatibility with old versions of GDB.\n\
+Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
+The special arg \"all\" is recognized to mean all signals except those\n\
+used by the debugger, typically SIGTRAP and SIGINT.\n",
+ "Recognized actions include \"s\" (toggles between stop and nostop), \n\
+\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
+nopass), \"Q\" (noprint)\n\
Stop means reenter debugger if this signal happens (implies print).\n\
+Print means print a message if this signal happens.\n\
Pass means let program see this signal; otherwise program doesn't know.\n\
-Pass and Stop may be combined.");
+Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
+Pass and Stop may be combined.", NULL));
+ }
- numsigs = signo_max () + 1;
- signal_stop = xmalloc (sizeof (signal_stop[0]) * numsigs);
- signal_print = xmalloc (sizeof (signal_print[0]) * numsigs);
- signal_program = xmalloc (sizeof (signal_program[0]) * numsigs);
+ if (!dbx_commands)
+ stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command,
+ "There is no `stop' command, but you can set a hook on `stop'.\n\
+This allows you to set a list of commands to be run each time execution\n\
+of the program stops.", &cmdlist);
+
+ numsigs = (int) TARGET_SIGNAL_LAST;
+ signal_stop = (unsigned char *)
+ xmalloc (sizeof (signal_stop[0]) * numsigs);
+ signal_print = (unsigned char *)
+ xmalloc (sizeof (signal_print[0]) * numsigs);
+ signal_program = (unsigned char *)
+ xmalloc (sizeof (signal_program[0]) * numsigs);
for (i = 0; i < numsigs; i++)
{
signal_stop[i] = 1;
/* Signals caused by debugger's own actions
should not be given to the program afterwards. */
- signal_program[SIGTRAP] = 0;
- signal_program[SIGINT] = 0;
+ signal_program[TARGET_SIGNAL_TRAP] = 0;
+ signal_program[TARGET_SIGNAL_INT] = 0;
/* Signals that are not errors should not normally enter the debugger. */
-#ifdef SIGALRM
- signal_stop[SIGALRM] = 0;
- signal_print[SIGALRM] = 0;
-#endif /* SIGALRM */
-#ifdef SIGVTALRM
- signal_stop[SIGVTALRM] = 0;
- signal_print[SIGVTALRM] = 0;
-#endif /* SIGVTALRM */
-#ifdef SIGPROF
- signal_stop[SIGPROF] = 0;
- signal_print[SIGPROF] = 0;
-#endif /* SIGPROF */
-#ifdef SIGCHLD
- signal_stop[SIGCHLD] = 0;
- signal_print[SIGCHLD] = 0;
-#endif /* SIGCHLD */
-#ifdef SIGCLD
- signal_stop[SIGCLD] = 0;
- signal_print[SIGCLD] = 0;
-#endif /* SIGCLD */
-#ifdef SIGIO
- signal_stop[SIGIO] = 0;
- signal_print[SIGIO] = 0;
-#endif /* SIGIO */
-#ifdef SIGURG
- signal_stop[SIGURG] = 0;
- signal_print[SIGURG] = 0;
-#endif /* SIGURG */
+ signal_stop[TARGET_SIGNAL_ALRM] = 0;
+ signal_print[TARGET_SIGNAL_ALRM] = 0;
+ signal_stop[TARGET_SIGNAL_VTALRM] = 0;
+ signal_print[TARGET_SIGNAL_VTALRM] = 0;
+ signal_stop[TARGET_SIGNAL_PROF] = 0;
+ signal_print[TARGET_SIGNAL_PROF] = 0;
+ signal_stop[TARGET_SIGNAL_CHLD] = 0;
+ signal_print[TARGET_SIGNAL_CHLD] = 0;
+ signal_stop[TARGET_SIGNAL_IO] = 0;
+ signal_print[TARGET_SIGNAL_IO] = 0;
+ signal_stop[TARGET_SIGNAL_POLL] = 0;
+ signal_print[TARGET_SIGNAL_POLL] = 0;
+ signal_stop[TARGET_SIGNAL_URG] = 0;
+ signal_print[TARGET_SIGNAL_URG] = 0;
+ signal_stop[TARGET_SIGNAL_WINCH] = 0;
+ signal_print[TARGET_SIGNAL_WINCH] = 0;
+
+ /* These signals are used internally by user-level thread
+ implementations. (See signal(5) on Solaris.) Like the above
+ signals, a healthy program receives and handles them as part of
+ its normal operation. */
+ signal_stop[TARGET_SIGNAL_LWP] = 0;
+ signal_print[TARGET_SIGNAL_LWP] = 0;
+ signal_stop[TARGET_SIGNAL_WAITING] = 0;
+ signal_print[TARGET_SIGNAL_WAITING] = 0;
+ signal_stop[TARGET_SIGNAL_CANCEL] = 0;
+ signal_print[TARGET_SIGNAL_CANCEL] = 0;
+
+#ifdef SOLIB_ADD
+ add_show_from_set
+ (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
+ (char *) &stop_on_solib_events,
+ "Set stopping for shared library events.\n\
+If nonzero, gdb will give control to the user when the dynamic linker\n\
+notifies gdb of shared library events. The most common event of interest\n\
+to the user would be loading/unloading of a new library.\n",
+ &setlist),
+ &showlist);
+#endif
+
+ c = add_set_enum_cmd ("follow-fork-mode",
+ class_run,
+ follow_fork_mode_kind_names,
+ (char *) &follow_fork_mode_string,
+/* ??rehrauer: The "both" option is broken, by what may be a 10.20
+ kernel problem. It's also not terribly useful without a GUI to
+ help the user drive two debuggers. So for now, I'm disabling
+ the "both" option. */
+/* "Set debugger response to a program call of fork \
+ or vfork.\n\
+ A fork or vfork creates a new process. follow-fork-mode can be:\n\
+ parent - the original process is debugged after a fork\n\
+ child - the new process is debugged after a fork\n\
+ both - both the parent and child are debugged after a fork\n\
+ ask - the debugger will ask for one of the above choices\n\
+ For \"both\", another copy of the debugger will be started to follow\n\
+ the new child process. The original debugger will continue to follow\n\
+ the original parent process. To distinguish their prompts, the\n\
+ debugger copy's prompt will be changed.\n\
+ For \"parent\" or \"child\", the unfollowed process will run free.\n\
+ By default, the debugger will follow the parent process.",
+ */
+ "Set debugger response to a program call of fork \
+or vfork.\n\
+A fork or vfork creates a new process. follow-fork-mode can be:\n\
+ parent - the original process is debugged after a fork\n\
+ child - the new process is debugged after a fork\n\
+ ask - the debugger will ask for one of the above choices\n\
+For \"parent\" or \"child\", the unfollowed process will run free.\n\
+By default, the debugger will follow the parent process.",
+ &setlist);
+/* c->function.sfunc = ; */
+ add_show_from_set (c, &showlist);
+
+ set_follow_fork_mode_command ("parent", 0, NULL);
+
+ c = add_set_enum_cmd ("scheduler-locking", class_run,
+ scheduler_enums, /* array of string names */
+ (char *) &scheduler_mode, /* current mode */
+ "Set mode for locking scheduler during execution.\n\
+off == no locking (threads may preempt at any time)\n\
+on == full locking (no thread except the current thread may run)\n\
+step == scheduler locked during every single-step operation.\n\
+ In this mode, no other thread may run during a step command.\n\
+ Other threads may run while stepping over a function call ('next').",
+ &setlist);
+
+ c->function.sfunc = set_schedlock_func; /* traps on target vector */
+ add_show_from_set (c, &showlist);
}
projects / thirdparty / binutils-gdb.git / blobdiff