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-rw-r--r--gdb/thread-db.c992
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diff --git a/gdb/thread-db.c b/gdb/thread-db.c
new file mode 100644
index 00000000000..7c3c0ae28fa
--- /dev/null
+++ b/gdb/thread-db.c
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+/* libthread_db assisted debugging support, generic parts.
+ Copyright 1999, 2000 Free Software Foundation, Inc.
+
+ 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 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., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+
+#include "gdb_assert.h"
+#include <dlfcn.h>
+#include "gdb_proc_service.h"
+#include "gdb_thread_db.h"
+
+#include "gdbthread.h"
+#include "inferior.h"
+#include "target.h"
+
+#ifndef LIBTHREAD_DB_SO
+#define LIBTHREAD_DB_SO "libthread_db.so.1"
+#endif
+
+/* If we're running on Linux, we must explicitly attach to any new threads. */
+
+/* FIXME: There is certainly some room for improvements:
+ - Cache LWP ids.
+ - Bypass libthread_db when fetching or storing registers for
+ threads bound to a LWP. */
+
+/* This module's target vector. */
+static struct target_ops thread_db_ops;
+
+/* The target vector that we call for things this module can't handle. */
+static struct target_ops *target_beneath;
+
+/* Pointer to the next function on the objfile event chain. */
+static void (*target_new_objfile_chain) (struct objfile *objfile);
+
+/* Non-zero if we're using this module's target vector. */
+static int using_thread_db;
+
+/* Non-zero if we have determined the signals used by the threads
+ library. */
+static int thread_signals;
+static sigset_t thread_stop_set;
+static sigset_t thread_print_set;
+
+/* Structure that identifies the child process for the
+ <proc_service.h> interface. */
+static struct ps_prochandle proc_handle;
+
+/* Connection to the libthread_db library. */
+static td_thragent_t *thread_agent;
+
+/* Pointers to the libthread_db functions. */
+
+static td_err_e (*td_init_p) (void);
+
+static td_err_e (*td_ta_new_p) (struct ps_prochandle *ps, td_thragent_t **ta);
+static td_err_e (*td_ta_map_id2thr_p) (const td_thragent_t *ta, thread_t pt,
+ td_thrhandle_t *__th);
+static td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta, lwpid_t lwpid,
+ td_thrhandle_t *th);
+static td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta,
+ td_thr_iter_f *callback,
+ void *cbdata_p, td_thr_state_e state,
+ int ti_pri, sigset_t *ti_sigmask_p,
+ unsigned int ti_user_flags);
+static td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta,
+ td_event_e event, td_notify_t *ptr);
+static td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta,
+ td_thr_events_t *event);
+static td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta,
+ td_event_msg_t *msg);
+
+static td_err_e (*td_thr_validate_p) (const td_thrhandle_t *th);
+static td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th,
+ td_thrinfo_t *infop);
+static td_err_e (*td_thr_getfpregs_p) (const td_thrhandle_t *th,
+ gdb_prfpregset_t *regset);
+static td_err_e (*td_thr_getgregs_p) (const td_thrhandle_t *th,
+ prgregset_t gregs);
+static td_err_e (*td_thr_setfpregs_p) (const td_thrhandle_t *th,
+ const gdb_prfpregset_t *fpregs);
+static td_err_e (*td_thr_setgregs_p) (const td_thrhandle_t *th,
+ prgregset_t gregs);
+static td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th, int event);
+
+/* Location of the thread creation event breakpoint. The code at this
+ location in the child process will be called by the pthread library
+ whenever a new thread is created. By setting a special breakpoint
+ at this location, GDB can detect when a new thread is created. We
+ obtain this location via the td_ta_event_addr call. */
+static CORE_ADDR td_create_bp_addr;
+
+/* Location of the thread death event breakpoint. */
+static CORE_ADDR td_death_bp_addr;
+
+/* Prototypes for local functions. */
+static int find_new_threads_callback (const td_thrhandle_t *th_p, void *data);
+
+
+/* Building process ids. */
+
+#ifndef TIDGET
+#define TIDGET(PID) (((PID) & 0x7fffffff) >> 16)
+#define PIDGET(PID) (((PID) & 0xffff))
+#define MERGEPID(PID, TID) (((PID) & 0xffff) | ((TID) << 16))
+#endif
+
+#define THREAD_FLAG 0x80000000
+
+#define is_lwp(pid) (((pid) & THREAD_FLAG) == 0 && TIDGET (pid))
+#define is_thread(pid) ((pid) & THREAD_FLAG)
+
+#define GET_PID(pid) PIDGET (pid)
+#define GET_LWP(pid) TIDGET (pid)
+#define GET_THREAD(pid) TIDGET (pid)
+
+#define BUILD_LWP(tid, pid) MERGEPID (pid, tid)
+#define BUILD_THREAD(tid, pid) (MERGEPID (pid, tid) | THREAD_FLAG)
+
+
+struct private_thread_info
+{
+ /* Cached LWP id. Must come first, see lin-lwp.c. */
+ lwpid_t lwpid;
+};
+
+
+/* Helper functions. */
+
+static void
+restore_inferior_pid (void *arg)
+{
+ int *saved_pid_ptr = arg;
+ inferior_pid = *saved_pid_ptr;
+ free (arg);
+}
+
+static struct cleanup *
+save_inferior_pid (void)
+{
+ int *saved_pid_ptr;
+
+ saved_pid_ptr = xmalloc (sizeof (int));
+ *saved_pid_ptr = inferior_pid;
+ return make_cleanup (restore_inferior_pid, saved_pid_ptr);
+}
+
+
+static char *
+thread_db_err_str (td_err_e err)
+{
+ static char buf[64];
+
+ switch (err)
+ {
+ case TD_OK:
+ return "generic 'call succeeded'";
+ case TD_ERR:
+ return "generic error";
+ case TD_NOTHR:
+ return "no thread to satisfy query";
+ case TD_NOSV:
+ return "no sync handle to satisfy query";
+ case TD_NOLWP:
+ return "no LWP to satisfy query";
+ case TD_BADPH:
+ return "invalid process handle";
+ case TD_BADTH:
+ return "invalid thread handle";
+ case TD_BADSH:
+ return "invalid synchronization handle";
+ case TD_BADTA:
+ return "invalid thread agent";
+ case TD_BADKEY:
+ return "invalid key";
+ case TD_NOMSG:
+ return "no event message for getmsg";
+ case TD_NOFPREGS:
+ return "FPU register set not available";
+ case TD_NOLIBTHREAD:
+ return "application not linked with libthread";
+ case TD_NOEVENT:
+ return "requested event is not supported";
+ case TD_NOCAPAB:
+ return "capability not available";
+ case TD_DBERR:
+ return "debugger service failed";
+ case TD_NOAPLIC:
+ return "operation not applicable to";
+ case TD_NOTSD:
+ return "no thread-specific data for this thread";
+ case TD_MALLOC:
+ return "malloc failed";
+ case TD_PARTIALREG:
+ return "only part of register set was written/read";
+ case TD_NOXREGS:
+ return "X register set not available for this thread";
+ default:
+ snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err);
+ return buf;
+ }
+}
+
+static char *
+thread_db_state_str (td_thr_state_e state)
+{
+ static char buf[64];
+
+ switch (state)
+ {
+ case TD_THR_STOPPED:
+ return "stopped by debugger";
+ case TD_THR_RUN:
+ return "runnable";
+ case TD_THR_ACTIVE:
+ return "active";
+ case TD_THR_ZOMBIE:
+ return "zombie";
+ case TD_THR_SLEEP:
+ return "sleeping";
+ case TD_THR_STOPPED_ASLEEP:
+ return "stopped by debugger AND blocked";
+ default:
+ snprintf (buf, sizeof (buf), "unknown thread_db state %d", state);
+ return buf;
+ }
+}
+
+
+/* Convert between user-level thread ids and LWP ids. */
+
+static int
+thread_from_lwp (int pid)
+{
+ td_thrinfo_t ti;
+ td_thrhandle_t th;
+ td_err_e err;
+
+ if (GET_LWP (pid) == 0)
+ pid = BUILD_LWP (pid, pid);
+
+ gdb_assert (is_lwp (pid));
+
+ err = td_ta_map_lwp2thr_p (thread_agent, GET_LWP (pid), &th);
+ if (err != TD_OK)
+ error ("Cannot find user-level thread for LWP %d: %s",
+ GET_LWP (pid), thread_db_err_str (err));
+
+ err = td_thr_get_info_p (&th, &ti);
+ if (err != TD_OK)
+ error ("Cannot get thread info: %s", thread_db_err_str (err));
+
+ return BUILD_THREAD (ti.ti_tid, GET_PID (pid));
+}
+
+static int
+lwp_from_thread (int pid)
+{
+ td_thrinfo_t ti;
+ td_thrhandle_t th;
+ td_err_e err;
+
+ if (! is_thread (pid))
+ return pid;
+
+ err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th);
+ if (err != TD_OK)
+ error ("Cannot find thread %ld: %s",
+ (long) GET_THREAD (pid), thread_db_err_str (err));
+
+ err = td_thr_get_info_p (&th, &ti);
+ if (err != TD_OK)
+ error ("Cannot get thread info: %s", thread_db_err_str (err));
+
+ return BUILD_LWP (ti.ti_lid, GET_PID (pid));
+}
+
+
+void
+thread_db_init (struct target_ops *target)
+{
+ target_beneath = target;
+}
+
+static int
+thread_db_load (void)
+{
+ void *handle;
+ td_err_e err;
+
+ handle = dlopen (LIBTHREAD_DB_SO, RTLD_NOW);
+ if (handle == NULL)
+ return 0;
+
+ /* Initialize pointers to the dynamic library functions we will use.
+ Essential functions first. */
+
+ td_init_p = dlsym (handle, "td_init");
+ if (td_init_p == NULL)
+ return 0;
+
+ td_ta_new_p = dlsym (handle, "td_ta_new");
+ if (td_ta_new_p == NULL)
+ return 0;
+
+ td_ta_map_id2thr_p = dlsym (handle, "td_ta_map_id2thr");
+ if (td_ta_map_id2thr_p == NULL)
+ return 0;
+
+ td_ta_map_lwp2thr_p = dlsym (handle, "td_ta_map_lwp2thr");
+ if (td_ta_map_lwp2thr_p == NULL)
+ return 0;
+
+ td_ta_thr_iter_p = dlsym (handle, "td_ta_thr_iter");
+ if (td_ta_thr_iter_p == NULL)
+ return 0;
+
+ td_thr_validate_p = dlsym (handle, "td_thr_validate");
+ if (td_thr_validate_p == NULL)
+ return 0;
+
+ td_thr_get_info_p = dlsym (handle, "td_thr_get_info");
+ if (td_thr_get_info_p == NULL)
+ return 0;
+
+ td_thr_getfpregs_p = dlsym (handle, "td_thr_getfpregs");
+ if (td_thr_getfpregs_p == NULL)
+ return 0;
+
+ td_thr_getgregs_p = dlsym (handle, "td_thr_getgregs");
+ if (td_thr_getgregs_p == NULL)
+ return 0;
+
+ td_thr_setfpregs_p = dlsym (handle, "td_thr_setfpregs");
+ if (td_thr_setfpregs_p == NULL)
+ return 0;
+
+ td_thr_setgregs_p = dlsym (handle, "td_thr_setgregs");
+ if (td_thr_setgregs_p == NULL)
+ return 0;
+
+ /* Initialize the library. */
+ err = td_init_p ();
+ if (err != TD_OK)
+ {
+ warning ("Cannot initialize libthread_db: %s", thread_db_err_str (err));
+ return 0;
+ }
+
+ /* These are not essential. */
+ td_ta_event_addr_p = dlsym (handle, "td_ta_event_addr");
+ td_ta_set_event_p = dlsym (handle, "td_ta_set_event");
+ td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg");
+ td_thr_event_enable_p = dlsym (handle, "td_thr_event_enable");
+
+ return 1;
+}
+
+static void
+enable_thread_event_reporting (void)
+{
+ td_thr_events_t events;
+ td_notify_t notify;
+ td_err_e err;
+
+ /* We cannot use the thread event reporting facility if these
+ functions aren't available. */
+ if (td_ta_event_addr_p == NULL || td_ta_set_event_p == NULL
+ || td_ta_event_getmsg_p == NULL || td_thr_event_enable_p == NULL)
+ return;
+
+ /* Set the process wide mask saying which events we're interested in. */
+ td_event_emptyset (&events);
+ td_event_addset (&events, TD_CREATE);
+#if 0
+ /* FIXME: kettenis/2000-04-23: The event reporting facility is
+ broken for TD_DEATH events in glibc 2.1.3, so don't enable it for
+ now. */
+ td_event_addset (&events, TD_DEATH);
+#endif
+
+ err = td_ta_set_event_p (thread_agent, &events);
+ if (err != TD_OK)
+ {
+ warning ("Unable to set global thread event mask: %s",
+ thread_db_err_str (err));
+ return;
+ }
+
+ /* Delete previous thread event breakpoints, if any. */
+ remove_thread_event_breakpoints ();
+
+ /* Get address for thread creation breakpoint. */
+ err = td_ta_event_addr_p (thread_agent, TD_CREATE, &notify);
+ if (err != TD_OK)
+ {
+ warning ("Unable to get location for thread creation breakpoint: %s",
+ thread_db_err_str (err));
+ return;
+ }
+
+ /* Set up the breakpoint. */
+ td_create_bp_addr = (CORE_ADDR) notify.u.bptaddr;
+ create_thread_event_breakpoint (td_create_bp_addr);
+
+ /* Get address for thread death breakpoint. */
+ err = td_ta_event_addr_p (thread_agent, TD_DEATH, &notify);
+ if (err != TD_OK)
+ {
+ warning ("Unable to get location for thread creation breakpoint: %s",
+ thread_db_err_str (err));
+ return;
+ }
+
+ /* Set up the breakpoint. */
+ td_death_bp_addr = (CORE_ADDR) notify.u.bptaddr;
+ create_thread_event_breakpoint (td_death_bp_addr);
+}
+
+static void
+disable_thread_event_reporting (void)
+{
+ td_thr_events_t events;
+
+ /* Set the process wide mask saying we aren't interested in any
+ events anymore. */
+ td_event_emptyset (&events);
+ td_ta_set_event_p (thread_agent, &events);
+
+ /* Delete thread event breakpoints, if any. */
+ remove_thread_event_breakpoints ();
+ td_create_bp_addr = 0;
+ td_death_bp_addr = 0;
+}
+
+static void
+check_thread_signals (void)
+{
+#ifdef GET_THREAD_SIGNALS
+ if (! thread_signals)
+ {
+ sigset_t mask;
+ int i;
+
+ GET_THREAD_SIGNALS (&mask);
+ sigemptyset (&thread_stop_set);
+ sigemptyset (&thread_print_set);
+
+ for (i = 0; i < NSIG; i++)
+ {
+ if (sigismember (&mask, i))
+ {
+ if (signal_stop_update (target_signal_from_host (i), 0))
+ sigaddset (&thread_stop_set, i);
+ if (signal_print_update (target_signal_from_host (i), 0))
+ sigaddset (&thread_print_set, i);
+ thread_signals = 1;
+ }
+ }
+ }
+#endif
+}
+
+static void
+disable_thread_signals (void)
+{
+#ifdef GET_THREAD_SIGNALS
+ if (thread_signals)
+ {
+ int i;
+
+ for (i = 0; i < NSIG; i++)
+ {
+ if (sigismember (&thread_stop_set, i))
+ signal_stop_update (target_signal_from_host (i), 1);
+ if (sigismember (&thread_print_set, i))
+ signal_print_update (target_signal_from_host (i), 1);
+ }
+
+ thread_signals = 0;
+ }
+#endif
+}
+
+static void
+thread_db_push_target (void)
+{
+ using_thread_db = 1;
+
+ /* Push this target vector. */
+ push_target (&thread_db_ops);
+
+ enable_thread_event_reporting ();
+}
+
+static void
+thread_db_unpush_target (void)
+{
+ /* Unpush this target vector. */
+ unpush_target (&thread_db_ops);
+
+ using_thread_db = 0;
+}
+
+static void
+thread_db_new_objfile (struct objfile *objfile)
+{
+ td_err_e err;
+
+ if (using_thread_db)
+ /* Nothing to do. The thread library was already detected and the
+ target vector was already activated. */
+ goto quit;
+
+ if (objfile == NULL)
+ /* Un-interesting object file. */
+ goto quit;
+
+ /* Initialize the structure that identifies the child process. */
+ proc_handle.pid = GET_PID (inferior_pid);
+
+ /* Now attempt to open a connection to the thread library running in
+ the child process. */
+ err = td_ta_new_p (&proc_handle, &thread_agent);
+ switch (err)
+ {
+ case TD_NOLIBTHREAD:
+ /* No thread library found in the child process, probably
+ because the child process isn't running yet. */
+ break;
+
+ case TD_OK:
+ /* The thread library was detected in the child; we go live now! */
+ thread_db_push_target ();
+
+ /* Find all user-space threads. */
+ err = td_ta_thr_iter_p (thread_agent, find_new_threads_callback,
+ &inferior_pid, TD_THR_ANY_STATE,
+ TD_THR_LOWEST_PRIORITY, TD_SIGNO_MASK,
+ TD_THR_ANY_USER_FLAGS);
+ if (err != TD_OK)
+ error ("Finding new threads failed: %s", thread_db_err_str (err));
+ break;
+
+ default:
+ warning ("Cannot initialize thread debugging library: %s",
+ thread_db_err_str (err));
+ break;
+ }
+
+ quit:
+ if (target_new_objfile_chain)
+ target_new_objfile_chain (objfile);
+}
+
+static void
+attach_thread (int pid, const td_thrhandle_t *th_p,
+ const td_thrinfo_t *ti_p, int verbose)
+{
+ struct thread_info *tp;
+ td_err_e err;
+
+ check_thread_signals ();
+
+ if (verbose)
+ printf_unfiltered ("[New %s]\n", target_pid_to_str (pid));
+
+ /* Add the thread to GDB's thread list. */
+ tp = add_thread (pid);
+ tp->private = xmalloc (sizeof (struct private_thread_info));
+ tp->private->lwpid = ti_p->ti_lid;
+
+ /* Under Linux, we have to attach to each and every thread. */
+#ifdef ATTACH_LWP
+ if (ti_p->ti_lid != GET_PID (pid))
+ ATTACH_LWP (BUILD_LWP (ti_p->ti_lid, GET_PID (pid)), 0);
+#endif
+
+ /* Enable thread event reporting for this thread. */
+ err = td_thr_event_enable_p (th_p, 1);
+ if (err != TD_OK)
+ error ("Cannot enable thread event reporting for %s: %s",
+ target_pid_to_str (pid), thread_db_err_str (err));
+}
+
+static void
+detach_thread (int pid, int verbose)
+{
+ if (verbose)
+ printf_unfiltered ("[%s exited]\n", target_pid_to_str (pid));
+}
+
+static void
+thread_db_detach (char *args, int from_tty)
+{
+ disable_thread_event_reporting ();
+ thread_db_unpush_target ();
+
+ target_beneath->to_detach (args, from_tty);
+}
+
+static void
+thread_db_resume (int pid, int step, enum target_signal signo)
+{
+ struct cleanup *old_chain = save_inferior_pid ();
+
+ if (pid == -1)
+ inferior_pid = lwp_from_thread (inferior_pid);
+ else if (is_thread (pid))
+ pid = lwp_from_thread (pid);
+
+ target_beneath->to_resume (pid, step, signo);
+
+ do_cleanups (old_chain);
+}
+
+/* Check if PID is currently stopped at the location of a thread event
+ breakpoint location. If it is, read the event message and act upon
+ the event. */
+
+static void
+check_event (int pid)
+{
+ td_event_msg_t msg;
+ td_thrinfo_t ti;
+ td_err_e err;
+ CORE_ADDR stop_pc;
+
+ /* Bail out early if we're not at a thread event breakpoint. */
+ stop_pc = read_pc_pid (pid) - DECR_PC_AFTER_BREAK;
+ if (stop_pc != td_create_bp_addr && stop_pc != td_death_bp_addr)
+ return;
+
+ err = td_ta_event_getmsg_p (thread_agent, &msg);
+ if (err != TD_OK)
+ {
+ if (err == TD_NOMSG)
+ return;
+
+ error ("Cannot get thread event message: %s", thread_db_err_str (err));
+ }
+
+ err = td_thr_get_info_p (msg.th_p, &ti);
+ if (err != TD_OK)
+ error ("Cannot get thread info: %s", thread_db_err_str (err));
+
+ pid = BUILD_THREAD (ti.ti_tid, GET_PID (pid));
+
+ switch (msg.event)
+ {
+ case TD_CREATE:
+#if 0
+ /* FIXME: kettenis/2000-08-26: Since we use td_ta_event_getmsg,
+ there is no guarantee that the breakpoint will match the
+ event. Should we use td_thr_event_getmsg instead? */
+
+ if (stop_pc != td_create_bp_addr)
+ error ("Thread creation event doesn't match breakpoint.");
+#endif
+
+ if (in_thread_list (pid))
+ error ("Spurious thread creation event.");
+
+ attach_thread (pid, msg.th_p, &ti, 1);
+ return;
+
+ case TD_DEATH:
+#if 0
+ /* FIXME: See TD_CREATE. */
+
+ if (stop_pc != td_death_bp_addr)
+ error ("Thread death event doesn't match breakpoint.");
+#endif
+
+ if (! in_thread_list (pid))
+ error ("Spurious thread death event.");
+
+ detach_thread (pid, 1);
+ return;
+
+ default:
+ error ("Spurious thread event.");
+ }
+}
+
+static int
+thread_db_wait (int pid, struct target_waitstatus *ourstatus)
+{
+ extern int trap_pid;
+
+ if (pid != -1 && is_thread (pid))
+ pid = lwp_from_thread (pid);
+
+ pid = target_beneath->to_wait (pid, ourstatus);
+
+ if (ourstatus->kind == TARGET_WAITKIND_EXITED)
+ return -1;
+
+ if (ourstatus->kind == TARGET_WAITKIND_STOPPED
+ && ourstatus->value.sig == TARGET_SIGNAL_TRAP)
+ /* Check for a thread event. */
+ check_event (pid);
+
+ if (trap_pid)
+ trap_pid = thread_from_lwp (trap_pid);
+
+ return thread_from_lwp (pid);
+}
+
+static int
+thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
+ struct target_ops *target)
+{
+ struct cleanup *old_chain = save_inferior_pid ();
+ int xfer;
+
+ if (is_thread (inferior_pid))
+ {
+ /* FIXME: This seems to be necessary to make sure breakpoints
+ are removed. */
+ if (! target_thread_alive (inferior_pid))
+ inferior_pid = GET_PID (inferior_pid);
+ else
+ inferior_pid = lwp_from_thread (inferior_pid);
+ }
+
+ xfer = target_beneath->to_xfer_memory (memaddr, myaddr, len, write, target);
+
+ do_cleanups (old_chain);
+ return xfer;
+}
+
+static void
+thread_db_fetch_registers (int regno)
+{
+ td_thrhandle_t th;
+ prgregset_t gregset;
+ gdb_prfpregset_t fpregset;
+ td_err_e err;
+
+ if (! is_thread (inferior_pid))
+ {
+ /* Pass the request to the target beneath us. */
+ target_beneath->to_fetch_registers (regno);
+ return;
+ }
+
+ err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (inferior_pid), &th);
+ if (err != TD_OK)
+ error ("Cannot find thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+
+ err = td_thr_getgregs_p (&th, gregset);
+ if (err != TD_OK)
+ error ("Cannot fetch general-purpose registers for thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+
+ err = td_thr_getfpregs_p (&th, &fpregset);
+ if (err != TD_OK)
+ error ("Cannot get floating-point registers for thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+
+ /* Note that we must call supply_gregset after calling the thread_db
+ routines because the thread_db routines call ps_lgetgregs and
+ friends which clobber GDB's register cache. */
+ supply_gregset ((gdb_gregset_t *) gregset);
+ supply_fpregset (&fpregset);
+}
+
+static void
+thread_db_store_registers (int regno)
+{
+ td_thrhandle_t th;
+ prgregset_t gregset;
+ gdb_prfpregset_t fpregset;
+ td_err_e err;
+
+ if (! is_thread (inferior_pid))
+ {
+ /* Pass the request to the target beneath us. */
+ target_beneath->to_store_registers (regno);
+ return;
+ }
+
+ err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (inferior_pid), &th);
+ if (err != TD_OK)
+ error ("Cannot find thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+
+ if (regno != -1)
+ {
+ char raw[MAX_REGISTER_RAW_SIZE];
+
+ read_register_gen (regno, raw);
+ thread_db_fetch_registers (-1);
+ supply_register (regno, raw);
+ }
+
+ fill_gregset ((gdb_gregset_t *) gregset, -1);
+ fill_fpregset (&fpregset, -1);
+
+ err = td_thr_setgregs_p (&th, gregset);
+ if (err != TD_OK)
+ error ("Cannot store general-purpose registers for thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+ err = td_thr_setfpregs_p (&th, &fpregset);
+ if (err != TD_OK)
+ error ("Cannot store floating-point registers for thread %ld: %s",
+ (long) GET_THREAD (inferior_pid), thread_db_err_str (err));
+}
+
+static void
+thread_db_kill (void)
+{
+ target_beneath->to_kill ();
+}
+
+static void
+thread_db_create_inferior (char *exec_file, char *allargs, char **env)
+{
+ /* We never want to actually create the inferior! If this is ever
+ called, it means we were on the target stack when the user said
+ "run". But we don't want to be on the new inferior's target
+ stack until the libthread_db connection is ready to be made. So
+ we unpush ourselves from the stack, and then invoke
+ find_default_create_inferior, which will invoke the appropriate
+ process_stratum target to do the create. */
+
+ thread_db_unpush_target ();
+
+ find_default_create_inferior (exec_file, allargs, env);
+}
+
+static void
+thread_db_mourn_inferior (void)
+{
+ remove_thread_event_breakpoints ();
+ thread_db_unpush_target ();
+
+ target_beneath->to_mourn_inferior ();
+}
+
+static int
+thread_db_thread_alive (int pid)
+{
+ if (is_thread (pid))
+ {
+ td_thrhandle_t th;
+ td_err_e err;
+
+ err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th);
+ if (err != TD_OK)
+ return 0;
+
+ err = td_thr_validate_p (&th);
+ if (err != TD_OK)
+ return 0;
+
+ return 1;
+ }
+
+ if (target_beneath->to_thread_alive)
+ return target_beneath->to_thread_alive (pid);
+
+ return 0;
+}
+
+static int
+find_new_threads_callback (const td_thrhandle_t *th_p, void *data)
+{
+ td_thrinfo_t ti;
+ td_err_e err;
+ int pid;
+
+ err = td_thr_get_info_p (th_p, &ti);
+ if (err != TD_OK)
+ error ("Cannot get thread info: %s", thread_db_err_str (err));
+
+ pid = BUILD_THREAD (ti.ti_tid, GET_PID (inferior_pid));
+
+ if (! in_thread_list (pid))
+ attach_thread (pid, th_p, &ti, 1);
+
+ return 0;
+}
+
+static void
+thread_db_find_new_threads (void)
+{
+ td_err_e err;
+
+ /* Iterate over all user-space threads to discover new threads. */
+ err = td_ta_thr_iter_p (thread_agent, find_new_threads_callback, NULL,
+ TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY,
+ TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS);
+ if (err != TD_OK)
+ error ("Cannot find new threads: %s", thread_db_err_str (err));
+}
+
+static char *
+thread_db_pid_to_str (int pid)
+{
+ if (is_thread (pid))
+ {
+ static char buf[64];
+ td_thrhandle_t th;
+ td_thrinfo_t ti;
+ td_err_e err;
+
+ err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th);
+ if (err != TD_OK)
+ error ("Cannot find thread %ld: %s",
+ (long) GET_THREAD (pid), thread_db_err_str (err));
+
+ err = td_thr_get_info_p (&th, &ti);
+ if (err != TD_OK)
+ error ("Cannot get thread info for thread %ld: %s",
+ (long) GET_THREAD (pid), thread_db_err_str (err));
+
+ if (ti.ti_state == TD_THR_ACTIVE && ti.ti_lid != 0)
+ {
+ snprintf (buf, sizeof (buf), "Thread %ld (LWP %d)",
+ (long) ti.ti_tid, ti.ti_lid);
+ }
+ else
+ {
+ snprintf (buf, sizeof (buf), "Thread %ld (%s)",
+ (long) ti.ti_tid, thread_db_state_str (ti.ti_state));
+ }
+
+ return buf;
+ }
+
+ if (target_beneath->to_pid_to_str (pid))
+ return target_beneath->to_pid_to_str (pid);
+
+ return normal_pid_to_str (pid);
+}
+
+static void
+init_thread_db_ops (void)
+{
+ thread_db_ops.to_shortname = "multi-thread";
+ thread_db_ops.to_longname = "multi-threaded child process.";
+ thread_db_ops.to_doc = "Threads and pthreads support.";
+ thread_db_ops.to_detach = thread_db_detach;
+ thread_db_ops.to_resume = thread_db_resume;
+ thread_db_ops.to_wait = thread_db_wait;
+ thread_db_ops.to_fetch_registers = thread_db_fetch_registers;
+ thread_db_ops.to_store_registers = thread_db_store_registers;
+ thread_db_ops.to_xfer_memory = thread_db_xfer_memory;
+ thread_db_ops.to_kill = thread_db_kill;
+ thread_db_ops.to_create_inferior = thread_db_create_inferior;
+ thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior;
+ thread_db_ops.to_thread_alive = thread_db_thread_alive;
+ thread_db_ops.to_find_new_threads = thread_db_find_new_threads;
+ thread_db_ops.to_pid_to_str = thread_db_pid_to_str;
+ thread_db_ops.to_stratum = thread_stratum;
+ thread_db_ops.to_has_thread_control = tc_schedlock;
+ thread_db_ops.to_magic = OPS_MAGIC;
+}
+
+void
+_initialize_thread_db (void)
+{
+ /* Only initialize the module if we can load libthread_db. */
+ if (thread_db_load ())
+ {
+ init_thread_db_ops ();
+ add_target (&thread_db_ops);
+
+ /* Add ourselves to objfile event chain. */
+ target_new_objfile_chain = target_new_objfile_hook;
+ target_new_objfile_hook = thread_db_new_objfile;
+ }
+}