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