* dec-thread.c: New file.

        * config/alpha/alpha-osf3.mh (NATDEPFILES): Add dec-thread.o.
        (NAT_CLIBS): Define.

1 files changed, 683 insertions, 0 deletions

diff --git a/gdb/dec-thread.c b/gdb/dec-thread.c
new file mode 100644
index 0000000..7f26166
--- /dev/null
+++ b/gdb/dec-thread.c
@@ -0,0 +1,683 @@
+/* Copyright (C) 2008 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 3 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, see <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "command.h"
+#include "gdbcmd.h"
+#include "target.h"
+#include "observer.h"
+#include <sys/procfs.h>
+#include "gregset.h"
+#include "regcache.h"
+#include "inferior.h"
+#include "gdbthread.h"
+
+#include <pthread_debug.h>
+
+/* Print debugging traces if set to non-zero.  */
+static int debug_dec_thread = 0;
+
+/* Non-zero if the dec-thread layer is active.  */
+static int dec_thread_active = 0;
+
+/* The pthread_debug context.  */
+pthreadDebugContext_t debug_context;
+
+/* The dec-thread target_ops structure.  */
+static struct target_ops dec_thread_ops;
+
+/* A copy of the target_ops over which our dec_thread_ops is pushed.  */
+static struct target_ops base_target;
+
+/* Print a debug trace if DEBUG_DEC_THREAD is set (its value is adjusted
+   by the user using "set debug dec-thread ...").  */
+
+static void
+debug (char *format, ...)
+{
+  if (debug_dec_thread)
+    {
+      va_list args;
+
+      va_start (args, format);
+      printf_unfiltered ("DEC Threads: ");
+      vprintf_unfiltered (format, args);
+      printf_unfiltered ("\n");
+      va_end (args);
+    }
+}
+
+/* pthread debug callbacks.  */
+
+static int
+suspend_clbk (void *caller_context)
+{
+  return ESUCCESS;
+}
+
+static int
+resume_clbk (void *caller_context)
+{
+  return ESUCCESS;
+} 
+
+static int
+hold_clbk (void *caller_context, pthreadDebugKId_t kernel_tid)
+{ 
+  return ESUCCESS;
+}
+
+static int
+unhold_clbk (void *caller_context, pthreadDebugKId_t kernel_tid)
+{
+  return ESUCCESS;
+}
+
+static int
+read_clbk (void *caller_context, void *address, void *buffer,
+           unsigned long size)
+{
+  int status = target_read_memory ((CORE_ADDR) address, buffer, size);
+
+  if (status != 0)
+    return EINVAL;
+
+  return ESUCCESS;
+}
+
+static int
+write_clbk (void *caller_context, void *address, void *buffer,
+            unsigned long size)
+{
+  int status = target_write_memory ((CORE_ADDR) address, buffer, size);
+  
+  if (status != 0)
+    return EINVAL;
+
+  return ESUCCESS;
+}
+
+/* Get integer regs */
+
+static int
+get_reg_clbk(void *caller_context, pthreadDebugGetRegRtn_t regs,
+             pthreadDebugKId_t kernel_tid)
+{
+  debug ("get_reg_clbk");
+
+  /* Not sure that we actually need to do anything in this callback.  */
+  return ESUCCESS;
+}
+
+/* Set integer regs */
+
+static int
+set_reg_clbk(void *caller_context, const pthreadDebugRegs_t *regs,
+             pthreadDebugKId_t kernel_tid)
+{
+  debug ("set_reg_clbk");
+
+  /* Not sure that we actually need to do anything in this callback.  */
+  return ESUCCESS;
+}
+
+static int
+output_clbk (void *caller_context, char *line)
+{
+  printf_filtered ("%s\n", line);
+  return ESUCCESS;
+}
+
+static int
+error_clbk (void *caller_context, char *line)
+{
+  fprintf_filtered (gdb_stderr, "%s\n", line);
+  return ESUCCESS;
+}
+
+/* Get floating-point regs.  */
+
+static int
+get_fpreg_clbk (void *caller_context, pthreadDebugFregs_p fregs,
+                pthreadDebugKId_t kernel_tid)
+{
+  debug ("get_fpreg_clbk");
+
+  /* Not sure that we actually need to do anything in this callback.  */
+  return ESUCCESS;
+}
+
+/* Set floating-point regs.  */
+
+static int
+set_fpreg_clbk (void *caller_context, const pthreadDebugFregs_t *fregs,
+                pthreadDebugKId_t kernel_tid)
+{
+  debug ("set_fpreg_clbk");
+
+  /* Not sure that we actually need to do anything in this callback.  */
+  return ESUCCESS;
+}
+
+static void *
+malloc_clbk (void *caller_context, size_t size)
+{
+  return xmalloc (size);
+}
+
+static void
+free_clbk (void *caller_context, void *address)
+{
+  xfree (address);
+}
+
+static int
+kthdinfo_clbk (pthreadDebugClient_t caller_context,
+               pthreadDebugKId_t kernel_tid,
+               pthreadDebugKThreadInfo_p thread_info)
+{
+  return ENOTSUP;
+}
+
+static int
+speckthd_clbk (pthreadDebugClient_t caller_context,
+               pthreadDebugSpecialType_t type,
+               pthreadDebugKId_t *kernel_tid)
+{
+  return ENOTSUP;
+}
+
+static pthreadDebugCallbacks_t debug_callbacks =
+{
+  PTHREAD_DEBUG_VERSION,
+  (pthreadDebugGetMemRtn_t) read_clbk,
+  (pthreadDebugSetMemRtn_t) write_clbk,
+  suspend_clbk,
+  resume_clbk,
+  kthdinfo_clbk,
+  hold_clbk,
+  unhold_clbk,
+  (pthreadDebugGetFregRtn_t) get_fpreg_clbk,
+  (pthreadDebugSetFregRtn_t) set_fpreg_clbk,
+  (pthreadDebugGetRegRtn_t) get_reg_clbk,
+  (pthreadDebugSetRegRtn_t) set_reg_clbk,
+  (pthreadDebugOutputRtn_t) output_clbk,
+  (pthreadDebugOutputRtn_t) error_clbk,
+  malloc_clbk,
+  free_clbk,
+  speckthd_clbk
+};
+
+/* Activate thread support if appropriate.  Do nothing if thread
+   support is already active.  */
+
+static void
+enable_dec_thread (void)
+{
+  struct minimal_symbol *msym;
+  void* caller_context;
+  int status;
+
+  /* If already active, nothing more to do.  */
+  if (dec_thread_active)
+    return;
+
+  msym = lookup_minimal_symbol ("__pthread_dbg_symtable", NULL, NULL);
+  if (msym == NULL)
+    {
+      debug ("enable_dec_thread: No __pthread_dbg_symtable");
+      return;
+    }
+
+  status = pthreadDebugContextInit (&caller_context, &debug_callbacks,
+                                    (void *) SYMBOL_VALUE_ADDRESS (msym),
+                                    &debug_context);
+  if (status != ESUCCESS)
+    {
+      debug ("enable_dec_thread: pthreadDebugContextInit -> %d",
+             status);
+      return;
+    }
+
+  base_target = current_target;
+  push_target (&dec_thread_ops);
+  dec_thread_active = 1;
+
+  debug ("enable_dec_thread: Thread support enabled.");
+}
+
+/* Deactivate thread support.  Do nothing is thread support is
+   already inactive.  */
+
+static void
+disable_dec_thread (void)
+{
+  if (!dec_thread_active)
+    return;
+
+  pthreadDebugContextDestroy (debug_context);
+  unpush_target (&dec_thread_ops);
+  dec_thread_active = 0;
+}
+
+/* A structure that contains a thread ID and is associated
+   pthreadDebugThreadInfo_t data.  */
+
+struct dec_thread_info
+{
+  pthreadDebugId_t thread;
+  pthreadDebugThreadInfo_t info;
+};
+typedef struct dec_thread_info dec_thread_info_s;
+
+/* The list of user threads.  */
+
+DEF_VEC_O (dec_thread_info_s);
+VEC(dec_thread_info_s) *dec_thread_list;
+
+/* Release the memory used by the given VECP thread list pointer.
+   Then set *VECP to NULL.  */
+
+static void
+free_dec_thread_info_vec (VEC(dec_thread_info_s) **vecp)
+{
+  int i;
+  struct dec_thread_info *item;
+  VEC(dec_thread_info_s) *vec = *vecp;
+
+  for (i = 0; VEC_iterate (dec_thread_info_s, vec, i, item); i++)
+     xfree (item);
+  VEC_free (dec_thread_info_s, vec);
+  *vecp = NULL;
+}
+
+/* Return a thread's ptid given its associated INFO.  */
+
+static ptid_t
+ptid_build_from_info (struct dec_thread_info info)
+{
+  int pid = ptid_get_pid (inferior_ptid);
+
+  return ptid_build (pid, 0, (long) info.thread);
+}
+
+/* Recompute the list of user threads and store the result in
+   DEC_THREAD_LIST.  */
+
+static void
+update_dec_thread_list (void)
+{
+  pthreadDebugId_t thread;
+  pthreadDebugThreadInfo_t info;
+  int res;
+
+  free_dec_thread_info_vec (&dec_thread_list);
+  res = pthreadDebugThdSeqInit (debug_context, &thread);
+  while (res == ESUCCESS)
+    {
+
+      res = pthreadDebugThdGetInfo (debug_context, thread, &info);
+      if (res != ESUCCESS)
+        warning (_("unable to get thread info, ignoring thread %ld"),
+                   thread);
+      else if (info.kind == PTHREAD_DEBUG_THD_KIND_INITIAL
+               || info.kind == PTHREAD_DEBUG_THD_KIND_NORMAL)
+        {
+          struct dec_thread_info *item = 
+            xmalloc (sizeof (struct dec_thread_info));
+
+          item->thread = thread;
+          item->info = info;
+          VEC_safe_push (dec_thread_info_s, dec_thread_list, item);
+        }
+      res = pthreadDebugThdSeqNext (debug_context, &thread);
+    }
+  pthreadDebugThdSeqDestroy (debug_context);
+}
+
+/* A callback to count the number of threads known to GDB.  */
+
+static int
+dec_thread_count_gdb_threads (struct thread_info *ignored, void *context)
+{
+  int *count = (int *) context;
+
+  *count++;
+  return 0;
+}
+
+/* A callback that saves the given thread INFO at the end of an
+   array.  The end of the array is given in the CONTEXT and is
+   incremented once the info has been added.  */
+
+static int
+dec_thread_add_gdb_thread (struct thread_info *info, void *context)
+{
+  struct thread_info ***listp = (struct thread_info ***) context;
+  
+  **listp = info;
+  *listp++;
+  return 0;
+}
+
+/* Resynchronize the list of threads known by GDB with the actual
+   list of threads reported by libpthread_debug.  */
+
+static void
+resync_thread_list (void)
+{
+  int i;
+  struct dec_thread_info *info;
+  int num_gdb_threads = 0;
+  struct thread_info **gdb_thread_list;
+  struct thread_info **next_thread_info;
+
+  update_dec_thread_list ();
+
+  /* Add new threads.  */
+
+  for (i = 0; VEC_iterate (dec_thread_info_s, dec_thread_list, i, info);
+       i++)
+    {
+      ptid_t ptid = ptid_build_from_info (*info);
+
+      if (!in_thread_list (ptid))
+        add_thread (ptid);
+    }
+
+  /* Remove threads that no longer exist.  To help with the search,
+     we build an array of GDB threads, and then iterate over this
+     array.  */
+
+  iterate_over_threads (dec_thread_count_gdb_threads,
+                        (void *) &num_gdb_threads);
+  gdb_thread_list = alloca (num_gdb_threads * sizeof (struct thread_info *));
+  next_thread_info = gdb_thread_list;
+  iterate_over_threads (dec_thread_add_gdb_thread, (void *) &next_thread_info);
+  for (i = 0; i < num_gdb_threads; i++)
+    {
+      int j;
+
+      for (j = 0; VEC_iterate (dec_thread_info_s, dec_thread_list, j, info);
+           j++)
+        if (ptid_equal (gdb_thread_list[i]->ptid,
+                         ptid_build_from_info (*info)))
+          break;
+      delete_thread (gdb_thread_list[i]->ptid);
+    }
+}
+
+/* The "to_detach" method of the dec_thread_ops.  */
+
+static void
+dec_thread_detach (char *args, int from_tty)
+{   
+  debug ("dec_thread_detach");
+
+  disable_dec_thread ();
+  base_target.to_detach (args, from_tty);
+}
+
+/* Return the ptid of the thread that is currently active.  */
+
+static ptid_t
+get_active_ptid (void)
+{
+  int i;
+  struct dec_thread_info *info;
+
+  for (i = 0; VEC_iterate (dec_thread_info_s, dec_thread_list, i, info);
+       i++)
+    if (info->info.state == PTHREAD_DEBUG_STATE_RUNNING)
+      return ptid_build_from_info (*info);
+
+  /* No active thread found.  This can happen when the program
+     has just exited.  */
+  return null_ptid;
+}
+
+/* The "to_wait" method of the dec_thread_ops.  */
+
+static ptid_t
+dec_thread_wait (ptid_t ptid, struct target_waitstatus *status)
+{
+  ptid_t active_ptid;
+
+  debug ("dec_thread_wait");
+
+  ptid = base_target.to_wait (ptid, status);
+
+  /* The ptid returned by the base_target is the ptid of the process.
+     We need to find which thread is currently active and return its
+     ptid.  */
+  resync_thread_list ();
+  active_ptid = get_active_ptid ();
+  if (ptid_equal (active_ptid, null_ptid))
+    return ptid;
+  return active_ptid;
+}
+
+/* Fetch the general purpose and floating point registers for the given
+   thread TID, and store the result in GREGSET and FPREGSET.  Return
+   zero if successful.  */
+
+static int
+dec_thread_get_regsets (pthreadDebugId_t tid, gdb_gregset_t *gregset,
+                        gdb_fpregset_t *fpregset)
+{
+  int res;
+  pthreadDebugRegs_t regs;
+  pthreadDebugFregs_t fregs;
+
+  res = pthreadDebugThdGetReg (debug_context, tid, &regs);
+  if (res != ESUCCESS)
+    {
+      debug ("dec_thread_fetch_registers: pthreadDebugThdGetReg -> %d", res);
+      return -1;
+    }
+  memcpy (gregset->regs, &regs, sizeof (regs));
+
+  res = pthreadDebugThdGetFreg (debug_context, tid, &fregs);
+  if (res != ESUCCESS)
+    {
+      debug ("dec_thread_fetch_registers: pthreadDebugThdGetFreg -> %d", res);
+      return -1;
+    }
+  memcpy (fpregset->regs, &fregs, sizeof (fregs));
+
+  return 0;
+}
+
+/* The "to_fetch_registers" method of the dec_thread_ops.
+
+   Because the dec-thread debug API doesn't allow us to fetch
+   only one register, we simply ignore regno and fetch+supply all
+   registers.  */
+
+static void
+dec_thread_fetch_registers (struct regcache *regcache, int regno)
+{
+  pthreadDebugId_t tid = ptid_get_tid (inferior_ptid);
+  gregset_t gregset;
+  fpregset_t fpregset;
+  int res;
+
+  debug ("dec_thread_fetch_registers (tid=%ld, regno=%d)", tid, regno);
+
+
+  if (tid == 0 || ptid_equal (inferior_ptid, get_active_ptid ()))
+    {
+      base_target.to_fetch_registers (regcache, regno);
+      return;
+    }
+
+  res = dec_thread_get_regsets (tid, &gregset, &fpregset);
+  if (res != 0)
+    return;
+
+  supply_gregset (regcache, &gregset);
+  supply_fpregset (regcache, &fpregset);
+}
+
+/* Store the registers given in GREGSET and FPREGSET into the associated
+   general purpose and floating point registers of thread TID.  Return
+   zero if successful.  */
+
+static int
+dec_thread_set_regsets (pthreadDebugId_t tid, gdb_gregset_t gregset,
+                        gdb_fpregset_t fpregset)
+{
+  int res;
+  pthreadDebugRegs_t regs;
+  pthreadDebugFregs_t fregs;
+
+  memcpy (&regs, gregset.regs, sizeof (regs));
+  res = pthreadDebugThdSetReg (debug_context, tid, &regs);
+  if (res != ESUCCESS)
+    {
+      debug ("dec_thread_fetch_registers: pthreadDebugThdSetReg -> %d", res);
+      return -1;
+    }
+
+  memcpy (&fregs, fpregset.regs, sizeof (fregs));
+  res = pthreadDebugThdSetFreg (debug_context, tid, &fregs);
+  if (res != ESUCCESS)
+    {
+      debug ("dec_thread_fetch_registers: pthreadDebugThdSetFreg -> %d", res);
+      return -1;
+    }
+
+  return 0;
+}
+
+/* The "to_store_registers" method of the dec_thread_ops.
+
+   Because the dec-thread debug API doesn't allow us to store
+   just one register, we store all the registers.  */
+
+static void
+dec_thread_store_registers (struct regcache *regcache, int regno)
+{
+  pthreadDebugId_t tid = ptid_get_tid (inferior_ptid);
+  gregset_t gregset;
+  fpregset_t fpregset;
+  int res;
+
+  debug ("dec_thread_store_registers (tid=%ld, regno=%d)", tid, regno);
+
+  if (tid == 0 || ptid_equal (inferior_ptid, get_active_ptid ()))
+    {
+      base_target.to_store_registers (regcache, regno);
+      return;
+    }
+
+  /* FIXME: brobecker/2008-05-28: I wonder if we could simply check
+     in which register set the register is and then only store the
+     registers for that register set, instead of storing both register
+     sets.  */
+  fill_gregset (regcache, &gregset, -1);
+  fill_fpregset (regcache, &fpregset, -1);
+  
+  res = dec_thread_set_regsets (tid, gregset, fpregset);
+  if (res != 0)
+    warning (_("failed to store registers."));
+}
+
+/* The "to_mourn_inferior" method of the dec_thread_ops.  */
+
+static void
+dec_thread_mourn_inferior (void)
+{
+  debug ("dec_thread_mourn_inferior");
+
+  disable_dec_thread ();
+  base_target.to_mourn_inferior ();
+}
+
+/* The "to_thread_alive" method of the dec_thread_ops.  */
+static int
+dec_thread_thread_alive (ptid_t ptid)
+{
+  debug ("dec_thread_thread_alive (tid=%ld)", ptid_get_tid (ptid));
+
+  /* The thread list maintained by GDB is up to date, since we update
+     it everytime we stop.   So check this list.  */
+  return in_thread_list (ptid);
+}
+
+/* The "to_pid_to_str" method of the dec_thread_ops.  */
+
+static char *
+dec_thread_pid_to_str (ptid_t ptid)
+{
+  static char *ret = NULL;
+
+  if (ptid_get_tid (ptid) == 0)
+    return base_target.to_pid_to_str (ptid);
+
+  /* Free previous return value; a new one will be allocated by
+     xstrprintf().  */
+  xfree (ret);
+
+  ret = xstrprintf (_("Thread %ld"), ptid_get_tid (ptid));
+  return ret;
+}
+
+/* A "new-objfile" observer.  Used to activate/deactivate dec-thread
+   support.  */
+
+static void
+dec_thread_new_objfile_observer (struct objfile *objfile)
+{
+  if (objfile != NULL)
+     enable_dec_thread ();
+  else
+     disable_dec_thread ();
+}
+
+static void
+init_dec_thread_ops (void)
+{
+  dec_thread_ops.to_shortname          = "dec-threads";
+  dec_thread_ops.to_longname           = _("DEC threads support");
+  dec_thread_ops.to_doc                = _("DEC threads support");
+  dec_thread_ops.to_detach             = dec_thread_detach;
+  dec_thread_ops.to_wait               = dec_thread_wait;
+  dec_thread_ops.to_fetch_registers    = dec_thread_fetch_registers;
+  dec_thread_ops.to_store_registers    = dec_thread_store_registers;
+  dec_thread_ops.to_mourn_inferior     = dec_thread_mourn_inferior;
+  dec_thread_ops.to_thread_alive       = dec_thread_thread_alive;
+  dec_thread_ops.to_pid_to_str         = dec_thread_pid_to_str;
+  dec_thread_ops.to_stratum            = thread_stratum;
+  dec_thread_ops.to_magic              = OPS_MAGIC;
+}
+
+void
+_initialize_dec_thread (void)
+{
+  init_dec_thread_ops ();
+  add_target (&dec_thread_ops);
+
+  observer_attach_new_objfile (dec_thread_new_objfile_observer);
+
+  add_setshow_boolean_cmd ("dec-thread", class_maintenance, &debug_dec_thread,
+                            _("Set debugging of DEC threads module."),
+                            _("Show debugging of DEC threads module."),
+                            _("Enables debugging output (used to debug GDB)."),
+                            NULL, NULL,
+                            &setdebuglist, &showdebuglist);
+}