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

Pedro Alves
2012-06-12T15:14:59Z

On 06/09/2012 01:46 PM, Yao Qi wrote:

> 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
>

(Just as reminder, ideally, at check in time, the patches would be sequenced
to not introduce any FAILs along the way.)

> gdb/gdbserver:
>
> 2012-06-09 Yao Qi <yao@codesourcery.com>
>
> PR gdb/14161.
> * tracepoint.c (gdb_agent_socket_init): Removed.

"Remove".

> (gdb_agent_remove_socket): New.
> (gdb_agent_helper_thread): Call gdb_agent_remove_socket at
> exit.
> Inline gdb_agent_socket_init here.

But why inline? We should just need to move the "name" local
of gdb_agent_socket_init a global? (btw, the 'agent_socket_name'
global is missing from the ChangeLog.)

> ---
> 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;

--
Pedro Alves