[PATCH 2/4] Remove socket file at exit.

[Yao Qi <yao at codesourcery dot com>]

This patch is to add code to call 'unlink' to make sure agent can remove socket
when inferior (after detached from GDB/GDBserver) exits.  It fixes the fail
below:

  FAIL: gdb.trace/strace.exp: remove_socket_after_detach: socket file removed

gdb/gdbserver:

2012-06-09  Yao Qi  <yao@codesourcery.com>

	PR gdb/14161.
	* tracepoint.c (gdb_agent_socket_init): Removed.
	(gdb_agent_remove_socket): New.
	(gdb_agent_helper_thread): Call gdb_agent_remove_socket at
	exit.
	Inline gdb_agent_socket_init here.
---
 gdb/gdbserver/tracepoint.c |   56 +++++++++++++++++++++----------------------
 1 files changed, 27 insertions(+), 29 deletions(-)

diff --git a/gdb/gdbserver/tracepoint.c b/gdb/gdbserver/tracepoint.c
index f103dfc..4e6c3ec 100644
--- a/gdb/gdbserver/tracepoint.c
+++ b/gdb/gdbserver/tracepoint.c
@@ -6748,29 +6748,6 @@ init_named_socket (const char *name)
   return fd;
 }
 
-static int
-gdb_agent_socket_init (void)
-{
-  int result, fd;
-  char name[UNIX_PATH_MAX];
-
-  result = xsnprintf (name, UNIX_PATH_MAX, "%s/gdb_ust%d",
-		      SOCK_DIR, getpid ());
-  if (result >= UNIX_PATH_MAX)
-    {
-      trace_debug ("string overflow allocating socket name");
-      return -1;
-    }
-
-  fd = init_named_socket (name);
-  if (fd < 0)
-    warning ("Error initializing named socket (%s) for communication with the "
-	     "ust helper thread. Check that directory exists and that it "
-	     "is writable.", name);
-
-  return fd;
-}
-
 #ifdef HAVE_UST
 
 /* The next marker to be returned on a qTsSTM command.  */
@@ -6995,27 +6972,48 @@ gdb_ust_init (void)
 #endif /* HAVE_UST */
 
 #include <sys/syscall.h>
+#include <stdlib.h>
+
+static char agent_socket_name[UNIX_PATH_MAX];
+
+static void
+gdb_agent_remove_socket (void)
+{
+  unlink (agent_socket_name);
+}
 
 /* Helper thread of agent.  */
 
 static void *
 gdb_agent_helper_thread (void *arg)
 {
-  int listen_fd;
+  atexit (gdb_agent_remove_socket);
 
   while (1)
     {
-      listen_fd = gdb_agent_socket_init ();
+      int listen_fd, result;
 
-      if (helper_thread_id == 0)
-	helper_thread_id = syscall (SYS_gettid);
+      result = xsnprintf (agent_socket_name, UNIX_PATH_MAX, "%s/gdb_ust%d",
+			  SOCK_DIR, getpid ());
+      if (result >= UNIX_PATH_MAX)
+	{
+	  trace_debug ("string overflow allocating socket name");
+	  break;
+	}
 
-      if (listen_fd == -1)
+      listen_fd = init_named_socket (agent_socket_name);
+      if (listen_fd < 0)
 	{
-	  warning ("could not create sync socket\n");
+	  warning ("Error initializing named socket (%s) for communication "
+		   "with the ust helper thread. Check that directory exists"
+		   " and that it is writable.", agent_socket_name);
 	  break;
+
 	}
 
+      if (helper_thread_id == 0)
+	helper_thread_id = syscall (SYS_gettid);
+
       while (1)
 	{
 	  socklen_t tmp;
-- 
1.7.0.4