Linux: on attach, attach to lwps listed under /proc/$pid/task/

[deliverable/binutils-gdb.git] / gdb / nat / linux-ptrace.c

diff --git a/gdb/nat/linux-ptrace.c b/gdb/nat/linux-ptrace.c
index 9eac8ffeaddcb56f6122cb5355d3876e275a358e..39815928103d20c67e63e162aa1c9ab32a2e4e3b 100644 (file)
--- a/gdb/nat/linux-ptrace.c
+++ b/gdb/nat/linux-ptrace.c
@@ -43,18 +43,44 @@ linux_ptrace_attach_fail_reason (pid_t pid, struct buffer *buffer)
 {
   pid_t tracerpid;
 
-  tracerpid = linux_proc_get_tracerpid (pid);
+  tracerpid = linux_proc_get_tracerpid_nowarn (pid);
   if (tracerpid > 0)
     buffer_xml_printf (buffer, _("process %d is already traced "
                                 "by process %d"),
                       (int) pid, (int) tracerpid);
 
-  if (linux_proc_pid_is_zombie (pid))
+  if (linux_proc_pid_is_zombie_nowarn (pid))
     buffer_xml_printf (buffer, _("process %d is a zombie "
                                 "- the process has already terminated"),
                       (int) pid);
 }
 
+/* See linux-ptrace.h.  */
+
+char *
+linux_ptrace_attach_fail_reason_string (ptid_t ptid, int err)
+{
+  static char *reason_string;
+  struct buffer buffer;
+  char *warnings;
+  long lwpid = ptid_get_lwp (ptid);
+
+  xfree (reason_string);
+
+  buffer_init (&buffer);
+  linux_ptrace_attach_fail_reason (lwpid, &buffer);
+  buffer_grow_str0 (&buffer, "");
+  warnings = buffer_finish (&buffer);
+  if (warnings[0] != '\0')
+    reason_string = xstrprintf ("%s (%d), %s",
+                               strerror (err), err, warnings);
+  else
+    reason_string = xstrprintf ("%s (%d)",
+                               strerror (err), err);
+  xfree (warnings);
+  return reason_string;
+}
+
 #if defined __i386__ || defined __x86_64__
 
 /* Address of the 'ret' instruction in asm code block below.  */
@@ -508,7 +534,8 @@ linux_disable_event_reporting (pid_t pid)
 static int
 ptrace_supports_feature (int ptrace_options)
 {
-  gdb_assert (current_ptrace_options >= 0);
+  if (current_ptrace_options == -1)
+    linux_check_ptrace_features ();
 
   return ((current_ptrace_options & ptrace_options) == ptrace_options);
 }