gdb/gdbserver/linux-low.h

   1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
   2    Copyright (C) 2002-2013 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "gdb_thread_db.h"
  20 #include <signal.h>
  21
  22 #include "gdbthread.h"
  23 #include "gdb_proc_service.h"
  24
  25 #define PTRACE_ARG3_TYPE void *
  26 #define PTRACE_ARG4_TYPE void *
  27 #define PTRACE_XFER_TYPE long
  28
  29 #ifdef HAVE_LINUX_REGSETS
  30 typedef void (*regset_fill_func) (struct regcache *, void *);
  31 typedef void (*regset_store_func) (struct regcache *, const void *);
  32 enum regset_type {
  33   GENERAL_REGS,
  34   FP_REGS,
  35   EXTENDED_REGS,
  36 };
  37
  38 struct regset_info
  39 {
  40   int get_request, set_request;
  41   /* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
  42      argument and the 4th argument should be "const struct iovec *".  */
  43   int nt_type;
  44   int size;
  45   enum regset_type type;
  46   regset_fill_func fill_function;
  47   regset_store_func store_function;
  48 };
  49 extern struct regset_info target_regsets[];
  50 #endif
  51
  52 struct process_info_private
  53 {
  54   /* Arch-specific additions.  */
  55   struct arch_process_info *arch_private;
  56
  57   /* libthread_db-specific additions.  Not NULL if this process has loaded
  58      thread_db, and it is active.  */
  59   struct thread_db *thread_db;
  60
  61   /* &_r_debug.  0 if not yet determined.  -1 if no PT_DYNAMIC in Phdrs.  */
  62   CORE_ADDR r_debug;
  63 };
  64
  65 struct lwp_info;
  66
  67 struct linux_target_ops
  68 {
  69   /* Architecture-specific setup.  */
  70   void (*arch_setup) (void);
  71
  72   int num_regs;
  73   int *regmap;
  74
  75   /* Regset support bitmap: 1 for registers that are transferred as a part
  76      of a regset, 0 for ones that need to be handled individually.  This
  77      can be NULL if all registers are transferred with regsets or regsets
  78      are not supported.  */
  79   unsigned char *regset_bitmap;
  80   int (*cannot_fetch_register) (int);
  81
  82   /* Returns 0 if we can store the register, 1 if we can not
  83      store the register, and 2 if failure to store the register
  84      is acceptable.  */
  85   int (*cannot_store_register) (int);
  86
  87   /* Hook to fetch a register in some non-standard way.  Used for
  88      example by backends that have read-only registers with hardcoded
  89      values (e.g., IA64's gr0/fr0/fr1).  Returns true if register
  90      REGNO was supplied, false if not, and we should fallback to the
  91      standard ptrace methods.  */
  92   int (*fetch_register) (struct regcache *regcache, int regno);
  93
  94   CORE_ADDR (*get_pc) (struct regcache *regcache);
  95   void (*set_pc) (struct regcache *regcache, CORE_ADDR newpc);
  96   const unsigned char *breakpoint;
  97   int breakpoint_len;
  98   CORE_ADDR (*breakpoint_reinsert_addr) (void);
  99
 100   int decr_pc_after_break;
 101   int (*breakpoint_at) (CORE_ADDR pc);
 102
 103   /* Breakpoint and watchpoint related functions.  See target.h for
 104      comments.  */
 105   int (*insert_point) (char type, CORE_ADDR addr, int len);
 106   int (*remove_point) (char type, CORE_ADDR addr, int len);
 107   int (*stopped_by_watchpoint) (void);
 108   CORE_ADDR (*stopped_data_address) (void);
 109
 110   /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
 111      for registers smaller than an xfer unit).  */
 112   void (*collect_ptrace_register) (struct regcache *regcache,
 113                                    int regno, char *buf);
 114   void (*supply_ptrace_register) (struct regcache *regcache,
 115                                   int regno, const char *buf);
 116
 117   /* Hook to convert from target format to ptrace format and back.
 118      Returns true if any conversion was done; false otherwise.
 119      If DIRECTION is 1, then copy from INF to NATIVE.
 120      If DIRECTION is 0, copy from NATIVE to INF.  */
 121   int (*siginfo_fixup) (siginfo_t *native, void *inf, int direction);
 122
 123   /* Hook to call when a new process is created or attached to.
 124      If extra per-process architecture-specific data is needed,
 125      allocate it here.  */
 126   struct arch_process_info * (*new_process) (void);
 127
 128   /* Hook to call when a new thread is detected.
 129      If extra per-thread architecture-specific data is needed,
 130      allocate it here.  */
 131   struct arch_lwp_info * (*new_thread) (void);
 132
 133   /* Hook to call prior to resuming a thread.  */
 134   void (*prepare_to_resume) (struct lwp_info *);
 135
 136   /* Hook to support target specific qSupported.  */
 137   void (*process_qsupported) (const char *);
 138
 139   /* Returns true if the low target supports tracepoints.  */
 140   int (*supports_tracepoints) (void);
 141
 142   /* Fill ADDRP with the thread area address of LWPID.  Returns 0 on
 143      success, -1 on failure.  */
 144   int (*get_thread_area) (int lwpid, CORE_ADDR *addrp);
 145
 146   /* Install a fast tracepoint jump pad.  See target.h for
 147      comments.  */
 148   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 149                                            CORE_ADDR collector,
 150                                            CORE_ADDR lockaddr,
 151                                            ULONGEST orig_size,
 152                                            CORE_ADDR *jump_entry,
 153                                            CORE_ADDR *trampoline,
 154                                            ULONGEST *trampoline_size,
 155                                            unsigned char *jjump_pad_insn,
 156                                            ULONGEST *jjump_pad_insn_size,
 157                                            CORE_ADDR *adjusted_insn_addr,
 158                                            CORE_ADDR *adjusted_insn_addr_end,
 159                                            char *err);
 160
 161   /* Return the bytecode operations vector for the current inferior.
 162      Returns NULL if bytecode compilation is not supported.  */
 163   struct emit_ops *(*emit_ops) (void);
 164
 165   /* Return the minimum length of an instruction that can be safely overwritten
 166      for use as a fast tracepoint.  */
 167   int (*get_min_fast_tracepoint_insn_len) (void);
 168
 169 };
 170
 171 extern struct linux_target_ops the_low_target;
 172
 173 #define ptid_of(proc) ((proc)->head.id)
 174 #define pid_of(proc) ptid_get_pid ((proc)->head.id)
 175 #define lwpid_of(proc) ptid_get_lwp ((proc)->head.id)
 176
 177 #define get_lwp(inf) ((struct lwp_info *)(inf))
 178 #define get_thread_lwp(thr) (get_lwp (inferior_target_data (thr)))
 179 #define get_lwp_thread(proc) ((struct thread_info *)                    \
 180                               find_inferior_id (&all_threads,           \
 181                                                 get_lwp (proc)->head.id))
 182
 183 struct lwp_info
 184 {
 185   struct inferior_list_entry head;
 186
 187   /* If this flag is set, the next SIGSTOP will be ignored (the
 188      process will be immediately resumed).  This means that either we
 189      sent the SIGSTOP to it ourselves and got some other pending event
 190      (so the SIGSTOP is still pending), or that we stopped the
 191      inferior implicitly via PTRACE_ATTACH and have not waited for it
 192      yet.  */
 193   int stop_expected;
 194
 195   /* When this is true, we shall not try to resume this thread, even
 196      if last_resume_kind isn't resume_stop.  */
 197   int suspended;
 198
 199   /* If this flag is set, the lwp is known to be stopped right now (stop
 200      event already received in a wait()).  */
 201   int stopped;
 202
 203   /* If this flag is set, the lwp is known to be dead already (exit
 204      event already received in a wait(), and is cached in
 205      status_pending).  */
 206   int dead;
 207
 208   /* When stopped is set, the last wait status recorded for this lwp.  */
 209   int last_status;
 210
 211   /* When stopped is set, this is where the lwp stopped, with
 212      decr_pc_after_break already accounted for.  */
 213   CORE_ADDR stop_pc;
 214
 215   /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
 216      been reported.  */
 217   int status_pending_p;
 218   int status_pending;
 219
 220   /* STOPPED_BY_WATCHPOINT is non-zero if this LWP stopped with a data
 221      watchpoint trap.  */
 222   int stopped_by_watchpoint;
 223
 224   /* On architectures where it is possible to know the data address of
 225      a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
 226      contains such data address.  Only valid if STOPPED_BY_WATCHPOINT
 227      is true.  */
 228   CORE_ADDR stopped_data_address;
 229
 230   /* If this is non-zero, it is a breakpoint to be reinserted at our next
 231      stop (SIGTRAP stops only).  */
 232   CORE_ADDR bp_reinsert;
 233
 234   /* If this flag is set, the last continue operation at the ptrace
 235      level on this process was a single-step.  */
 236   int stepping;
 237
 238   /* If this flag is set, we need to set the event request flags the
 239      next time we see this LWP stop.  */
 240   int must_set_ptrace_flags;
 241
 242   /* If this is non-zero, it points to a chain of signals which need to
 243      be delivered to this process.  */
 244   struct pending_signals *pending_signals;
 245
 246   /* A link used when resuming.  It is initialized from the resume request,
 247      and then processed and cleared in linux_resume_one_lwp.  */
 248   struct thread_resume *resume;
 249
 250   /* True if it is known that this lwp is presently collecting a fast
 251      tracepoint (it is in the jump pad or in some code that will
 252      return to the jump pad.  Normally, we won't care about this, but
 253      we will if a signal arrives to this lwp while it is
 254      collecting.  */
 255   int collecting_fast_tracepoint;
 256
 257   /* If this is non-zero, it points to a chain of signals which need
 258      to be reported to GDB.  These were deferred because the thread
 259      was doing a fast tracepoint collect when they arrived.  */
 260   struct pending_signals *pending_signals_to_report;
 261
 262   /* When collecting_fast_tracepoint is first found to be 1, we insert
 263      a exit-jump-pad-quickly breakpoint.  This is it.  */
 264   struct breakpoint *exit_jump_pad_bkpt;
 265
 266   /* True if the LWP was seen stop at an internal breakpoint and needs
 267      stepping over later when it is resumed.  */
 268   int need_step_over;
 269
 270 #ifdef USE_THREAD_DB
 271   int thread_known;
 272   /* The thread handle, used for e.g. TLS access.  Only valid if
 273      THREAD_KNOWN is set.  */
 274   td_thrhandle_t th;
 275 #endif
 276
 277   /* Arch-specific additions.  */
 278   struct arch_lwp_info *arch_private;
 279 };
 280
 281 extern struct inferior_list all_lwps;
 282
 283 int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);
 284
 285 void linux_attach_lwp (unsigned long pid);
 286 struct lwp_info *find_lwp_pid (ptid_t ptid);
 287 void linux_stop_lwp (struct lwp_info *lwp);
 288
 289 /* From thread-db.c  */
 290 int thread_db_init (int use_events);
 291 void thread_db_detach (struct process_info *);
 292 void thread_db_mourn (struct process_info *);
 293 int thread_db_handle_monitor_command (char *);
 294 int thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
 295                                CORE_ADDR load_module, CORE_ADDR *address);
 296 int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp);