gdb/linux-nat.h

   1 /* Native debugging support for GNU/Linux (LWP layer).
   2
   3    Copyright (C) 2000-2012 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "target.h"
  21
  22 #include <signal.h>
  23
  24 struct arch_lwp_info;
  25
  26 /* Ways to "resume" a thread.  */
  27
  28 enum resume_kind
  29 {
  30   /* Thread should continue.  */
  31   resume_continue,
  32
  33   /* Thread should single-step.  */
  34   resume_step,
  35
  36   /* Thread should be stopped.  */
  37   resume_stop
  38 };
  39
  40 /* Structure describing an LWP.  This is public only for the purposes
  41    of ALL_LWPS; target-specific code should generally not access it
  42    directly.  */
  43
  44 struct lwp_info
  45 {
  46   /* The process id of the LWP.  This is a combination of the LWP id
  47      and overall process id.  */
  48   ptid_t ptid;
  49
  50   /* Non-zero if this LWP is cloned.  In this context "cloned" means
  51      that the LWP is reporting to its parent using a signal other than
  52      SIGCHLD.  */
  53   int cloned;
  54
  55   /* Non-zero if we sent this LWP a SIGSTOP (but the LWP didn't report
  56      it back yet).  */
  57   int signalled;
  58
  59   /* Non-zero if this LWP is stopped.  */
  60   int stopped;
  61
  62   /* Non-zero if this LWP will be/has been resumed.  Note that an LWP
  63      can be marked both as stopped and resumed at the same time.  This
  64      happens if we try to resume an LWP that has a wait status
  65      pending.  We shouldn't let the LWP run until that wait status has
  66      been processed, but we should not report that wait status if GDB
  67      didn't try to let the LWP run.  */
  68   int resumed;
  69
  70   /* The last resume GDB requested on this thread.  */
  71   enum resume_kind last_resume_kind;
  72
  73   /* If non-zero, a pending wait status.  */
  74   int status;
  75
  76   /* Non-zero if we were stepping this LWP.  */
  77   int step;
  78
  79   /* Non-zero si_signo if this LWP stopped with a trap.  si_addr may
  80      be the address of a hardware watchpoint.  */
  81   siginfo_t siginfo;
  82
  83   /* STOPPED_BY_WATCHPOINT is non-zero if this LWP stopped with a data
  84      watchpoint trap.  */
  85   int stopped_by_watchpoint;
  86
  87   /* On architectures where it is possible to know the data address of
  88      a triggered watchpoint, STOPPED_DATA_ADDRESS_P is non-zero, and
  89      STOPPED_DATA_ADDRESS contains such data address.  Otherwise,
  90      STOPPED_DATA_ADDRESS_P is false, and STOPPED_DATA_ADDRESS is
  91      undefined.  Only valid if STOPPED_BY_WATCHPOINT is true.  */
  92   int stopped_data_address_p;
  93   CORE_ADDR stopped_data_address;
  94
  95   /* Non-zero if we expect a duplicated SIGINT.  */
  96   int ignore_sigint;
  97
  98   /* If WAITSTATUS->KIND != TARGET_WAITKIND_SPURIOUS, the waitstatus
  99      for this LWP's last event.  This may correspond to STATUS above,
 100      or to a local variable in lin_lwp_wait.  */
 101   struct target_waitstatus waitstatus;
 102
 103   /* Signal wether we are in a SYSCALL_ENTRY or
 104      in a SYSCALL_RETURN event.
 105      Values:
 106      - TARGET_WAITKIND_SYSCALL_ENTRY
 107      - TARGET_WAITKIND_SYSCALL_RETURN */
 108   int syscall_state;
 109
 110   /* The processor core this LWP was last seen on.  */
 111   int core;
 112
 113   /* Arch-specific additions.  */
 114   struct arch_lwp_info *arch_private;
 115
 116   /* Next LWP in list.  */
 117   struct lwp_info *next;
 118 };
 119
 120 /* The global list of LWPs, for ALL_LWPS.  Unlike the threads list,
 121    there is always at least one LWP on the list while the GNU/Linux
 122    native target is active.  */
 123 extern struct lwp_info *lwp_list;
 124
 125 /* Iterate over each active thread (light-weight process).  */
 126 #define ALL_LWPS(LP)                                                    \
 127   for ((LP) = lwp_list;                                                 \
 128        (LP) != NULL;                                                    \
 129        (LP) = (LP)->next)
 130
 131 #define GET_LWP(ptid)           ptid_get_lwp (ptid)
 132 #define GET_PID(ptid)           ptid_get_pid (ptid)
 133 #define is_lwp(ptid)            (GET_LWP (ptid) != 0)
 134 #define BUILD_LWP(lwp, pid)     ptid_build (pid, lwp, 0)
 135
 136 /* Attempt to initialize libthread_db.  */
 137 void check_for_thread_db (void);
 138
 139 int thread_db_attach_lwp (ptid_t ptid);
 140
 141 /* Return the set of signals used by the threads library.  */
 142 extern void lin_thread_get_thread_signals (sigset_t *mask);
 143
 144 /* Find process PID's pending signal set from /proc/pid/status.  */
 145 void linux_proc_pending_signals (int pid, sigset_t *pending,
 146                                  sigset_t *blocked, sigset_t *ignored);
 147
 148 /* linux-nat functions for handling fork events.  */
 149 extern void linux_enable_event_reporting (ptid_t ptid);
 150
 151 extern int lin_lwp_attach_lwp (ptid_t ptid);
 152
 153 extern void linux_stop_lwp (struct lwp_info *lwp);
 154
 155 /* Iterator function for lin-lwp's lwp list.  */
 156 struct lwp_info *iterate_over_lwps (ptid_t filter,
 157                                     int (*callback) (struct lwp_info *,
 158                                                      void *),
 159                                     void *data);
 160
 161 typedef int (*linux_nat_iterate_watchpoint_lwps_ftype) (struct lwp_info *lwp,
 162                                                         void *arg);
 163
 164 extern void linux_nat_iterate_watchpoint_lwps
 165   (linux_nat_iterate_watchpoint_lwps_ftype callback, void *callback_data);
 166
 167 /* Create a prototype generic GNU/Linux target.  The client can
 168    override it with local methods.  */
 169 struct target_ops * linux_target (void);
 170
 171 /* Create a generic GNU/Linux target using traditional
 172    ptrace register access.  */
 173 struct target_ops *
 174 linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int));
 175
 176 /* Register the customized GNU/Linux target.  This should be used
 177    instead of calling add_target directly.  */
 178 void linux_nat_add_target (struct target_ops *);
 179
 180 /* Register a method to call whenever a new thread is attached.  */
 181 void linux_nat_set_new_thread (struct target_ops *, void (*) (struct lwp_info *));
 182
 183 /* Register a method that converts a siginfo object between the layout
 184    that ptrace returns, and the layout in the architecture of the
 185    inferior.  */
 186 void linux_nat_set_siginfo_fixup (struct target_ops *,
 187                                   int (*) (siginfo_t *,
 188                                            gdb_byte *,
 189                                            int));
 190
 191 /* Register a method to call prior to resuming a thread.  */
 192
 193 void linux_nat_set_prepare_to_resume (struct target_ops *,
 194                                       void (*) (struct lwp_info *));
 195
 196 /* Update linux-nat internal state when changing from one fork
 197    to another.  */
 198 void linux_nat_switch_fork (ptid_t new_ptid);
 199
 200 /* Return the saved siginfo associated with PTID.  */
 201 siginfo_t *linux_nat_get_siginfo (ptid_t ptid);
 202
 203 /* Set alternative SIGTRAP-like events recognizer.  */
 204 void linux_nat_set_status_is_event (struct target_ops *t,
 205                                     int (*status_is_event) (int status));