gdb/linux-nat.h

   1 /* Native debugging support for GNU/Linux (LWP layer).
   2
   3    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
   4    2010, 2011 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "target.h"
  22
  23 #include <signal.h>
  24
  25 /* Ways to "resume" a thread.  */
  26
  27 enum resume_kind
  28 {
  29   /* Thread should continue.  */
  30   resume_continue,
  31
  32   /* Thread should single-step.  */
  33   resume_step,
  34
  35   /* Thread should be stopped.  */
  36   resume_stop
  37 };
  38
  39 /* Structure describing an LWP.  This is public only for the purposes
  40    of ALL_LWPS; target-specific code should generally not access it
  41    directly.  */
  42
  43 struct lwp_info
  44 {
  45   /* The process id of the LWP.  This is a combination of the LWP id
  46      and overall process id.  */
  47   ptid_t ptid;
  48
  49   /* Non-zero if this LWP is cloned.  In this context "cloned" means
  50      that the LWP is reporting to its parent using a signal other than
  51      SIGCHLD.  */
  52   int cloned;
  53
  54   /* Non-zero if we sent this LWP a SIGSTOP (but the LWP didn't report
  55      it back yet).  */
  56   int signalled;
  57
  58   /* Non-zero if this LWP is stopped.  */
  59   int stopped;
  60
  61   /* Non-zero if this LWP will be/has been resumed.  Note that an LWP
  62      can be marked both as stopped and resumed at the same time.  This
  63      happens if we try to resume an LWP that has a wait status
  64      pending.  We shouldn't let the LWP run until that wait status has
  65      been processed, but we should not report that wait status if GDB
  66      didn't try to let the LWP run.  */
  67   int resumed;
  68
  69   /* The last resume GDB requested on this thread.  */
  70   enum resume_kind last_resume_kind;
  71
  72   /* If non-zero, a pending wait status.  */
  73   int status;
  74
  75   /* Non-zero if we were stepping this LWP.  */
  76   int step;
  77
  78   /* Non-zero si_signo if this LWP stopped with a trap.  si_addr may
  79      be the address of a hardware watchpoint.  */
  80   struct siginfo siginfo;
  81
  82   /* STOPPED_BY_WATCHPOINT is non-zero if this LWP stopped with a data
  83      watchpoint trap.  */
  84   int stopped_by_watchpoint;
  85
  86   /* On architectures where it is possible to know the data address of
  87      a triggered watchpoint, STOPPED_DATA_ADDRESS_P is non-zero, and
  88      STOPPED_DATA_ADDRESS contains such data address.  Otherwise,
  89      STOPPED_DATA_ADDRESS_P is false, and STOPPED_DATA_ADDRESS is
  90      undefined.  Only valid if STOPPED_BY_WATCHPOINT is true.  */
  91   int stopped_data_address_p;
  92   CORE_ADDR stopped_data_address;
  93
  94   /* Non-zero if we expect a duplicated SIGINT.  */
  95   int ignore_sigint;
  96
  97   /* If WAITSTATUS->KIND != TARGET_WAITKIND_SPURIOUS, the waitstatus
  98      for this LWP's last event.  This may correspond to STATUS above,
  99      or to a local variable in lin_lwp_wait.  */
 100   struct target_waitstatus waitstatus;
 101
 102   /* Signal wether we are in a SYSCALL_ENTRY or
 103      in a SYSCALL_RETURN event.
 104      Values:
 105      - TARGET_WAITKIND_SYSCALL_ENTRY
 106      - TARGET_WAITKIND_SYSCALL_RETURN */
 107   int syscall_state;
 108
 109   /* The processor core this LWP was last seen on.  */
 110   int core;
 111
 112   /* Next LWP in list.  */
 113   struct lwp_info *next;
 114 };
 115
 116 /* The global list of LWPs, for ALL_LWPS.  Unlike the threads list,
 117    there is always at least one LWP on the list while the GNU/Linux
 118    native target is active.  */
 119 extern struct lwp_info *lwp_list;
 120
 121 /* Iterate over the PTID each active thread (light-weight process).  There
 122    must be at least one.  */
 123 #define ALL_LWPS(LP, PTID)                                              \
 124   for ((LP) = lwp_list, (PTID) = (LP)->ptid;                            \
 125        (LP) != NULL;                                                    \
 126        (LP) = (LP)->next, (PTID) = (LP) ? (LP)->ptid : (PTID))
 127
 128 #define GET_LWP(ptid)           ptid_get_lwp (ptid)
 129 #define GET_PID(ptid)           ptid_get_pid (ptid)
 130 #define is_lwp(ptid)            (GET_LWP (ptid) != 0)
 131 #define BUILD_LWP(lwp, pid)     ptid_build (pid, lwp, 0)
 132
 133 /* Attempt to initialize libthread_db.  */
 134 void check_for_thread_db (void);
 135
 136 int thread_db_attach_lwp (ptid_t ptid);
 137
 138 /* Return the set of signals used by the threads library.  */
 139 extern void lin_thread_get_thread_signals (sigset_t *mask);
 140
 141 /* Find process PID's pending signal set from /proc/pid/status.  */
 142 void linux_proc_pending_signals (int pid, sigset_t *pending,
 143                                  sigset_t *blocked, sigset_t *ignored);
 144
 145 /* linux-nat functions for handling fork events.  */
 146 extern void linux_enable_event_reporting (ptid_t ptid);
 147
 148 extern int lin_lwp_attach_lwp (ptid_t ptid);
 149
 150 /* Iterator function for lin-lwp's lwp list.  */
 151 struct lwp_info *iterate_over_lwps (ptid_t filter,
 152                                     int (*callback) (struct lwp_info *,
 153                                                      void *),
 154                                     void *data);
 155
 156 /* Create a prototype generic GNU/Linux target.  The client can
 157    override it with local methods.  */
 158 struct target_ops * linux_target (void);
 159
 160 /* Create a generic GNU/Linux target using traditional
 161    ptrace register access.  */
 162 struct target_ops *
 163 linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int));
 164
 165 /* Register the customized GNU/Linux target.  This should be used
 166    instead of calling add_target directly.  */
 167 void linux_nat_add_target (struct target_ops *);
 168
 169 /* Register a method to call whenever a new thread is attached.  */
 170 void linux_nat_set_new_thread (struct target_ops *, void (*) (ptid_t));
 171
 172 /* Register a method that converts a siginfo object between the layout
 173    that ptrace returns, and the layout in the architecture of the
 174    inferior.  */
 175 void linux_nat_set_siginfo_fixup (struct target_ops *,
 176                                   int (*) (struct siginfo *,
 177                                            gdb_byte *,
 178                                            int));
 179
 180 /* Update linux-nat internal state when changing from one fork
 181    to another.  */
 182 void linux_nat_switch_fork (ptid_t new_ptid);
 183
 184 /* Return the saved siginfo associated with PTID.  */
 185 struct siginfo *linux_nat_get_siginfo (ptid_t ptid);
 186
 187 /* Compute and return the processor core of a given thread.  */
 188 int linux_nat_core_of_thread_1 (ptid_t ptid);
 189
 190 /* Set alternative SIGTRAP-like events recognizer.  */
 191 void linux_nat_set_status_is_event (struct target_ops *t,
 192                                     int (*status_is_event) (int status));