* bsd-uthread.h: New file.

* bsd-uthread.c: New file.
* Makefile.in (bsd_uthread_h): New variable.
(ALLDEPFILES): Add bsd-uthread.c.
(bsd-uthread.o): New dependency.

1 files changed, 516 insertions, 0 deletions

diff --git a/gdb/bsd-uthread.c b/gdb/bsd-uthread.c
new file mode 100644
index 00000000000..5041eb871e6
--- /dev/null
+++ b/gdb/bsd-uthread.c
@@ -0,0 +1,516 @@
+/* BSD user-level threads support.
+
+   Copyright 2005 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 "gdbcore.h"
+#include "gdbthread.h"
+#include "inferior.h"
+#include "objfiles.h"
+#include "observer.h"
+#include "regcache.h"
+#include "solist.h"
+#include "symfile.h"
+#include "target.h"
+
+#include "gdb_assert.h"
+#include "gdb_obstack.h"
+
+#include "bsd-uthread.h"
+
+/* HACK: Save the bsd_uthreads ops returned by bsd_uthread_target.  */
+static struct target_ops *bsd_uthread_ops_hack;
+
+
+/* Architecture-specific operations.  */
+
+/* Per-architecture data key.  */
+static struct gdbarch_data *bsd_uthread_data;
+
+struct bsd_uthread_ops
+{
+  /* Supply registers for an inactive thread to a register cache.  */
+  void (*supply_uthread)(struct regcache *, int, CORE_ADDR);
+
+  /* Collect registers for an inactive thread from a register cache.  */
+  void (*collect_uthread)(const struct regcache *, int, CORE_ADDR);
+};
+
+static void *
+bsd_uthread_init (struct obstack *obstack)
+{
+  struct bsd_uthread_ops *ops;
+
+  ops = OBSTACK_ZALLOC (obstack, struct bsd_uthread_ops);
+  return ops;
+}
+
+/* Set the function that supplies registers from an inactive thread
+   for architecture GDBARCH to SUPPLY_UTHREAD.  */
+
+void
+bsd_uthread_set_supply_uthread (struct gdbarch *gdbarch,
+				void (*supply_uthread) (struct regcache *,
+							int, CORE_ADDR))
+{
+  struct bsd_uthread_ops *ops = gdbarch_data (gdbarch, bsd_uthread_data);
+  ops->supply_uthread = supply_uthread;
+}
+
+/* Set the function that collects registers for an inactive thread for
+   architecture GDBARCH to SUPPLY_UTHREAD.  */
+
+void
+bsd_uthread_set_collect_uthread (struct gdbarch *gdbarch,
+			 void (*collect_uthread) (const struct regcache *,
+						  int, CORE_ADDR))
+{
+  struct bsd_uthread_ops *ops = gdbarch_data (gdbarch, bsd_uthread_data);
+  ops->collect_uthread = collect_uthread;
+}
+
+/* Magic number to help recognize a valid thread structure.  */
+#define BSD_UTHREAD_PTHREAD_MAGIC	0xd09ba115
+
+/* Check whether the thread structure at ADDR is valid.  */
+
+static void
+bsd_uthread_check_magic (CORE_ADDR addr)
+{
+  ULONGEST magic = read_memory_unsigned_integer (addr, 4);
+
+  if (magic != BSD_UTHREAD_PTHREAD_MAGIC)
+    error ("Bad magic");
+}
+
+/* Thread states.  */
+#define BSD_UTHREAD_PS_RUNNING	0
+#define BSD_UTHREAD_PS_DEAD	18
+
+/* Address of the pointer to the the thread structure for the running
+   thread.  */
+static CORE_ADDR bsd_uthread_thread_run_addr;
+
+/* Address of the list of all threads.  */
+static CORE_ADDR bsd_uthread_thread_list_addr;
+
+/* Offsets of various "interesting" bits in the thread structure.  */
+static int bsd_uthread_thread_state_offset = -1;
+static int bsd_uthread_thread_next_offset = -1;
+static int bsd_uthread_thread_ctx_offset;
+
+/* Name of shared threads library.  */
+static const char *bsd_uthread_solib_name;
+
+/* Non-zero if the thread startum implemented by this module is active.  */
+static int bsd_uthread_active;
+
+static CORE_ADDR
+bsd_uthread_lookup_address (const char *name, struct objfile *objfile)
+{
+  struct minimal_symbol *sym;
+
+  sym = lookup_minimal_symbol (name, NULL, objfile);
+  if (sym)
+    return SYMBOL_VALUE_ADDRESS (sym);
+
+  return 0;
+}
+
+static int
+bsd_uthread_lookup_offset (const char *name, struct objfile *objfile)
+{
+  CORE_ADDR addr;
+
+  addr = bsd_uthread_lookup_address (name, objfile);
+  if (addr == 0)
+    return 0;
+
+  return read_memory_unsigned_integer (addr, 4);
+}
+
+/* If OBJFILE contains the symbols corresponding to one of the
+   supported user-level threads libraries, activate the thread stratum
+   implemented by this module.  */
+
+static int
+bsd_uthread_activate (struct objfile *objfile)
+{
+  struct gdbarch *gdbarch = current_gdbarch;
+  struct bsd_uthread_ops *ops = gdbarch_data (gdbarch, bsd_uthread_data);
+
+  /* Skip if the thread stratum has already been activated.  */
+  if (bsd_uthread_active)
+    return 0;
+
+  /* There's no point in enabling this module if no
+     architecture-specific operations are provided.  */
+  if (!ops->supply_uthread)
+    return 0;
+
+  bsd_uthread_thread_run_addr =
+    bsd_uthread_lookup_address ("_thread_run", objfile);
+  if (bsd_uthread_thread_run_addr == 0)
+    return 0;
+
+  bsd_uthread_thread_list_addr =
+    bsd_uthread_lookup_address ("_thread_list", objfile);
+  if (bsd_uthread_thread_list_addr == 0)
+    return 0;
+
+  bsd_uthread_thread_state_offset =
+    bsd_uthread_lookup_offset ("_thread_state_offset", objfile);
+  if (bsd_uthread_thread_state_offset == 0)
+    return 0;
+
+  bsd_uthread_thread_next_offset =
+    bsd_uthread_lookup_offset ("_thread_next_offset", objfile);
+  if (bsd_uthread_thread_next_offset == 0)
+    return 0;
+
+  bsd_uthread_thread_ctx_offset =
+    bsd_uthread_lookup_offset ("_thread_ctx_offset", objfile);
+
+  push_target (bsd_uthread_ops_hack);
+  bsd_uthread_active = 1;
+  return 1;
+}
+
+/* Deactivate the thread stratum implemented by this module.  */
+
+static void
+bsd_uthread_deactivate (void)
+{
+  /* Skip if the thread stratum has already been deactivated.  */
+  if (!bsd_uthread_active)
+    return;
+
+  bsd_uthread_active = 0;
+  unpush_target (bsd_uthread_ops_hack);
+
+  bsd_uthread_thread_run_addr = 0;
+  bsd_uthread_thread_list_addr = 0;
+  bsd_uthread_thread_state_offset = 0;
+  bsd_uthread_thread_next_offset = 0;
+  bsd_uthread_thread_ctx_offset = 0;
+  bsd_uthread_solib_name = NULL;
+}
+
+void
+bsd_uthread_inferior_created (struct target_ops *ops, int from_tty)
+{
+  bsd_uthread_activate (NULL);
+}
+
+/* Likely candidates for the threads library.  */
+static const char *bsd_uthread_solib_names[] =
+{
+  "/usr/lib/libc_r.so",		/* FreeBSD */
+  "/usr/lib/libpthread.so",	/* OpenBSD */
+  NULL
+};
+
+void
+bsd_uthread_solib_loaded (struct so_list *so)
+{
+  const char **names = bsd_uthread_solib_names;
+
+  for (names = bsd_uthread_solib_names; *names; names++)
+    {
+      if (strncmp (so->so_original_name, *names, strlen (*names)) == 0)
+	{
+	  solib_read_symbols (so, so->from_tty);
+
+	  if (bsd_uthread_activate (so->objfile))
+	    {
+	      bsd_uthread_solib_name == so->so_original_name;
+	      return;
+	    }
+	}
+    }
+}
+
+void
+bsd_uthread_solib_unloaded (struct so_list *so)
+{
+  if (!bsd_uthread_solib_name)
+    return;
+
+  if (strcmp (so->so_original_name, bsd_uthread_solib_name) == 0)
+    bsd_uthread_deactivate ();
+}
+
+static void
+bsd_uthread_mourn_inferior (void)
+{
+  find_target_beneath (bsd_uthread_ops_hack)->to_mourn_inferior ();
+  bsd_uthread_deactivate ();
+}
+
+static void
+bsd_uthread_fetch_registers (int regnum)
+{
+  struct gdbarch *gdbarch = current_gdbarch;
+  struct bsd_uthread_ops *ops = gdbarch_data (gdbarch, bsd_uthread_data);
+  CORE_ADDR addr = ptid_get_tid (inferior_ptid);
+  CORE_ADDR active_addr;
+
+  /* Always fetch the appropriate registers from the layer beneath.  */
+  find_target_beneath (bsd_uthread_ops_hack)->to_fetch_registers (regnum);
+
+  /* FIXME: That might have gotten us more than we asked for.  Make
+     sure we overwrite all relevant registers with values from the
+     thread structure.  This can go once we fix the underlying target.  */
+  regnum = -1;
+
+  active_addr = read_memory_typed_address (bsd_uthread_thread_run_addr,
+					   builtin_type_void_data_ptr);
+  if (addr != 0 && addr != active_addr)
+    {
+      bsd_uthread_check_magic (addr);
+      ops->supply_uthread (current_regcache, regnum,
+			   addr + bsd_uthread_thread_ctx_offset);
+    }
+}
+
+static void
+bsd_uthread_store_registers (int regnum)
+{
+  struct gdbarch *gdbarch = current_gdbarch;
+  struct bsd_uthread_ops *ops = gdbarch_data (gdbarch, bsd_uthread_data);
+  CORE_ADDR addr = ptid_get_tid (inferior_ptid);
+  CORE_ADDR active_addr;
+
+  active_addr = read_memory_typed_address (bsd_uthread_thread_run_addr,
+					   builtin_type_void_data_ptr);
+  if (addr != 0 && addr != active_addr)
+    {
+      bsd_uthread_check_magic (addr);
+      ops->collect_uthread (current_regcache, regnum,
+			    addr + bsd_uthread_thread_ctx_offset);
+    }
+  else
+    {
+      /* Updating the thread that is currently running; pass the
+         request to the layer beneath.  */
+      find_target_beneath (bsd_uthread_ops_hack)->to_store_registers (regnum);
+    }
+}
+
+/* FIXME: This function is only there because otherwise GDB tries to
+   invoke deprecate_xfer_memory.  */
+
+static LONGEST
+bsd_uthread_xfer_partial (struct target_ops *ops, enum target_object object,
+			  const char *annex, void *readbuf,
+			  const void *writebuf, ULONGEST offset, LONGEST len)
+{
+  gdb_assert (ops->beneath->to_xfer_partial);
+  return ops->beneath->to_xfer_partial (ops->beneath, object, annex, readbuf,
+					writebuf, offset, len);
+}
+
+static ptid_t
+bsd_uthread_wait (ptid_t ptid, struct target_waitstatus *status)
+{
+  CORE_ADDR addr;
+
+  /* Pass the request to the layer beneath.  */
+  ptid = find_target_beneath (bsd_uthread_ops_hack)->to_wait (ptid, status);
+
+  /* Fetch the corresponding thread ID, and augment the returned
+     process ID with it.  */
+  addr = read_memory_typed_address (bsd_uthread_thread_run_addr,
+				    builtin_type_void_data_ptr);
+  if (addr != 0)
+    {
+      char buf[4];
+
+      /* FIXME: For executables linked statically with the threads
+         library, we end up here before the program has actually been
+         executed.  In that case ADDR will be garbage since it has
+         been read from the wrong virtual memory image.  */
+      if (target_read_memory (addr, buf, 4) == 0)
+	{
+	  ULONGEST magic = extract_unsigned_integer (buf, 4);
+	  if (magic == BSD_UTHREAD_PTHREAD_MAGIC)
+	    ptid = ptid_build (ptid_get_pid (ptid), 0, addr);
+	}
+    }
+
+  /* HACK: Twiddle INFERIOR_PTID such that the initial thread of a
+     process isn't recognized as a new thread.  */
+  if (ptid_get_tid (ptid) != 0 && !in_thread_list (ptid)
+      && ptid_get_tid (inferior_ptid) == 0)
+    {
+      add_thread (ptid);
+      inferior_ptid = ptid;
+    }
+
+  return ptid;
+}
+
+static void
+bsd_uthread_resume (ptid_t ptid, int step, enum target_signal sig)
+{
+  /* Pass the request to the layer beneath.  */
+  find_target_beneath (bsd_uthread_ops_hack)->to_resume (ptid, step, sig);
+}
+
+static int
+bsd_uthread_thread_alive (ptid_t ptid)
+{
+  CORE_ADDR addr = ptid_get_tid (inferior_ptid);
+
+  if (addr != 0)
+    {
+      int offset = bsd_uthread_thread_state_offset;
+      ULONGEST state;
+
+      bsd_uthread_check_magic (addr);
+
+      state = read_memory_unsigned_integer (addr + offset, 4);
+      if (state == BSD_UTHREAD_PS_DEAD)
+	return 0;
+    }
+
+  return find_target_beneath (bsd_uthread_ops_hack)->to_thread_alive (ptid);
+}
+
+static void
+bsd_uthread_find_new_threads (void)
+{
+  pid_t pid = ptid_get_pid (inferior_ptid);
+  int offset = bsd_uthread_thread_next_offset;
+  CORE_ADDR addr;
+
+  addr = read_memory_typed_address (bsd_uthread_thread_list_addr,
+				    builtin_type_void_data_ptr);
+  while (addr != 0)
+    {
+      ptid_t ptid = ptid_build (pid, 0, addr);
+
+      if (!in_thread_list (ptid))
+	add_thread (ptid);
+
+      addr = read_memory_typed_address (addr + offset,
+					builtin_type_void_data_ptr);
+    }
+}
+
+/* Possible states a thread can be in.  */
+static char *bsd_uthread_state[] =
+{
+  "RUNNING",
+  "SIGTHREAD",
+  "MUTEX_WAIT",
+  "COND_WAIT",
+  "FDLR_WAIT",
+  "FDLW_WAIT",
+  "FDR_WAIT",
+  "FDW_WAIT",
+  "FILE_WAIT",
+  "POLL_WAIT",
+  "SELECT_WAIT",
+  "SLEEP_WAIT",
+  "WAIT_WAIT",
+  "SIGSUSPEND",
+  "SIGWAIT",
+  "SPINBLOCK",
+  "JOIN",
+  "SUSPENDED",
+  "DEAD",
+  "DEADLOCK"
+};
+
+/* Return a string describing th state of the thread specified by
+   INFO.  */
+
+static char *
+bsd_uthread_extra_thread_info (struct thread_info *info)
+{
+  CORE_ADDR addr = ptid_get_tid (info->ptid);
+
+  if (addr != 0)
+    {
+      int offset = bsd_uthread_thread_state_offset;
+      ULONGEST state;
+
+      state = read_memory_unsigned_integer (addr + offset, 4);
+      if (state < ARRAY_SIZE (bsd_uthread_state))
+	return bsd_uthread_state[state];
+    }
+
+  return NULL;
+}
+
+static char *
+bsd_uthread_pid_to_str (ptid_t ptid)
+{
+  if (ptid_get_tid (ptid) != 0)
+    {
+      static char buf[64];
+      int size;
+
+      size = snprintf (buf, sizeof buf, "process %d, thread 0x%lx",
+		       ptid_get_pid (ptid), ptid_get_tid (ptid));
+      gdb_assert (size < sizeof buf);
+      return buf;
+    }
+
+  return normal_pid_to_str (ptid);
+}
+
+struct target_ops *
+bsd_uthread_target (void)
+{
+  struct target_ops *t = XZALLOC (struct target_ops);
+
+  t->to_shortname = "bsd-uthreads";
+  t->to_longname = "BSD user-level threads";
+  t->to_doc = "BSD user-level threads";
+  t->to_mourn_inferior = bsd_uthread_mourn_inferior;
+  t->to_fetch_registers = bsd_uthread_fetch_registers;
+  t->to_store_registers = bsd_uthread_store_registers;
+  t->to_xfer_partial = bsd_uthread_xfer_partial;
+  t->to_wait = bsd_uthread_wait;
+  t->to_resume = bsd_uthread_resume;
+  t->to_thread_alive = bsd_uthread_thread_alive;
+  t->to_find_new_threads = bsd_uthread_find_new_threads;
+  t->to_extra_thread_info = bsd_uthread_extra_thread_info;
+  t->to_pid_to_str = bsd_uthread_pid_to_str;
+  t->to_stratum = thread_stratum;
+  t->to_magic = OPS_MAGIC;
+  bsd_uthread_ops_hack = t;
+
+  return t;
+}
+
+void
+_initialize_bsd_uthread (void)
+{
+  add_target (bsd_uthread_target ());
+
+  bsd_uthread_data = gdbarch_data_register_pre_init (bsd_uthread_init);
+
+  observer_attach_inferior_created (bsd_uthread_inferior_created);
+  observer_attach_solib_loaded (bsd_uthread_solib_loaded);
+  observer_attach_solib_unloaded (bsd_uthread_solib_unloaded);
+}