Display per-thread information for threads in FreeBSD cores.

Display the LWP ID of each thread in a FreeBSD core.  Extract thread
names from the per-thread THRMISC note.

gdb/ChangeLog:

	* fbsd_tdep.c (fbsd_core_pid_to_str): New function.
	(fbsd_core_thread_name): New function.
	(fbsd_init_abi): Add "core_pid_to_str" gdbarch method.
	Add "core_thread_name" gdbarch method.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index b54ac3f7d1336f92c2a4bba257d183febca544c4..400305a49b27c0390f2134704883924f0354f55c 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2016-01-19  John Baldwin  <jhb@FreeBSD.org>
+
+       * fbsd_tdep.c (fbsd_core_pid_to_str): New function.
+       (fbsd_core_thread_name): New function.
+       (fbsd_init_abi): Add "core_pid_to_str" gdbarch method.
+       Add "core_thread_name" gdbarch method.
+
 2016-01-19  John Baldwin  <jhb@FreeBSD.org>
 
        * corelow.c (core_thread_name): New function.

diff --git a/gdb/fbsd-tdep.c b/gdb/fbsd-tdep.c
index 0ef94d6b7e0efdbb017b1d194ce291d967179dbd..4284f3809b41ed65f15de41f221481b61aeea90a 100644 (file)
--- a/gdb/fbsd-tdep.c
+++ b/gdb/fbsd-tdep.c
@@ -28,6 +28,70 @@
 #include "fbsd-tdep.h"
 
 
+/* This is how we want PTIDs from core files to be printed.  */
+
+static char *
+fbsd_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid)
+{
+  static char buf[80];
+
+  if (ptid_get_lwp (ptid) != 0)
+    {
+      xsnprintf (buf, sizeof buf, "LWP %ld", ptid_get_lwp (ptid));
+      return buf;
+    }
+
+  return normal_pid_to_str (ptid);
+}
+
+/* Extract the name assigned to a thread from a core.  Returns the
+   string in a static buffer.  */
+
+static const char *
+fbsd_core_thread_name (struct gdbarch *gdbarch, struct thread_info *thr)
+{
+  static char buf[80];
+  struct bfd_section *section;
+  bfd_size_type size;
+  char sectionstr[32];
+
+  if (ptid_get_lwp (thr->ptid) != 0)
+    {
+      /* FreeBSD includes a NT_FREEBSD_THRMISC note for each thread
+        whose contents are defined by a "struct thrmisc" declared in
+        <sys/procfs.h> on FreeBSD.  The per-thread name is stored as
+        a null-terminated string as the first member of the
+        structure.  Rather than define the full structure here, just
+        extract the null-terminated name from the start of the
+        note.  */
+      xsnprintf (sectionstr, sizeof sectionstr, ".thrmisc/%ld",
+               ptid_get_lwp (thr->ptid));
+      section = bfd_get_section_by_name (core_bfd, sectionstr);
+      if (section != NULL && bfd_section_size (core_bfd, section) > 0)
+       {
+         /* Truncate the name if it is longer than "buf".  */
+         size = bfd_section_size (core_bfd, section);
+         if (size > sizeof buf - 1)
+           size = sizeof buf - 1;
+         if (bfd_get_section_contents (core_bfd, section, buf, (file_ptr) 0,
+                                       size)
+             && buf[0] != '\0')
+           {
+             buf[size] = '\0';
+
+             /* Note that each thread will report the process command
+                as its thread name instead of an empty name if a name
+                has not been set explicitly.  Return a NULL name in
+                that case.  */
+             if (strcmp (buf, elf_tdata (core_bfd)->core->program) != 0)
+               return buf;
+           }
+       }
+    }
+
+  return NULL;
+}
+
 static int
 find_signalled_thread (struct thread_info *info, void *data)
 {
@@ -132,5 +196,7 @@ fbsd_make_corefile_notes (struct gdbarch *gdbarch, bfd *obfd, int *note_size)
 void
 fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
+  set_gdbarch_core_pid_to_str (gdbarch, fbsd_core_pid_to_str);
+  set_gdbarch_core_thread_name (gdbarch, fbsd_core_thread_name);
   set_gdbarch_make_corefile_notes (gdbarch, fbsd_make_corefile_notes);
 }