RFA: lin-lwp cleanup

Daniel Jacobowitz
2003-08-26T19:32:24Z

This patch doesn't do anything particularly important. I just moved some
code from stop_wait_callback out to a new function. I thought I'd need it
for my next patch; I turned out not to, but it's still cleaner this way.

Also fixes the two small problems I asked Jeff about earlier today - an
extra call to lin_lwp_thread_alive and a missing delete_thread.

Is this OK?

--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer

2003-08-26 Daniel Jacobowitz <drow@mvista.com>

* lin-lwp.c (wait_lwp): New function, copied from
stop_wait_callback. Clean up.
(stop_wait_callback): Use wait_lwp.

Index: lin-lwp.c
===================================================================
RCS file: /cvs/src/src/gdb/lin-lwp.c,v
retrieving revision 1.49
diff -u -p -r1.49 lin-lwp.c
--- lin-lwp.c 17 Aug 2003 18:52:59 -0000 1.49
+++ lin-lwp.c 26 Aug 2003 19:26:43 -0000
@@ -585,6 +585,77 @@ kill_lwp (int lwpid, int signo)
return kill (lwpid, signo);
}

+/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
+ exited. */
+
+static int
+wait_lwp (struct lwp_info *lp)
+{
+ pid_t pid;
+ int status;
+ int thread_dead = 0;
+
+ gdb_assert (!lp->stopped);
+ gdb_assert (lp->status == 0);
+
+ pid = waitpid (GET_LWP (lp->ptid), &status, 0);
+ if (pid == -1 && errno == ECHILD)
+ {
+ pid = waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
+ if (pid == -1 && errno == ECHILD)
+ {
+ /* The thread has previously exited. We need to delete it now
+ because in the case of NPTL threads, there won't be an
+ exit event unless it is the main thread. */
+ thread_dead = 1;
+ if (debug_lin_lwp)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
+ target_pid_to_str (lp->ptid));
+ }
+ }
+
+ if (!thread_dead)
+ {
+ gdb_assert (pid == GET_LWP (lp->ptid));
+
+ if (debug_lin_lwp)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "WL: waitpid %s received %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str (status));
+ }
+ }
+
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ {
+ thread_dead = 1;
+ if (debug_lin_lwp)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+ }
+
+ if (thread_dead)
+ {
+ if (in_thread_list (lp->ptid))
+ {
+ /* Core GDB cannot deal with us deleting the current thread. */
+ if (!ptid_equal (lp->ptid, inferior_ptid))
+ delete_thread (lp->ptid);
+ printf_unfiltered ("[%s exited]\n",
+ target_pid_to_str (lp->ptid));
+ }
+
+ delete_lwp (lp->ptid);
+ return 0;
+ }
+
+ gdb_assert (WIFSTOPPED (status));
+
+ return status;
+}
+
/* Send a SIGSTOP to LP. */

static int
@@ -627,86 +698,11 @@ stop_wait_callback (struct lwp_info *lp,

if (!lp->stopped && lp->signalled)
{
- pid_t pid;
int status;

- gdb_assert (lp->status == 0);
-
- pid = waitpid (GET_LWP (lp->ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
- {
- pid = waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
- if (pid == -1 && errno == ECHILD)
- {
- /* The thread has previously exited. We need to delete it now
- because in the case of nptl threads, there won't be an
- exit event unless it is the main thread. */
- if (debug_lin_lwp)
- fprintf_unfiltered (gdb_stdlog,
- "SWC: %s exited.\n",
- target_pid_to_str (lp->ptid));
- delete_lwp (lp->ptid);
- return 0;
- }
- }
-
- gdb_assert (pid == GET_LWP (lp->ptid));
-
- if (debug_lin_lwp)
- {
- fprintf_unfiltered (gdb_stdlog,
- "SWC: waitpid %s received %s\n",
- target_pid_to_str (lp->ptid),
- status_to_str (status));
- }
-
- /* Check if the thread has exited. */
- if (WIFEXITED (status) || WIFSIGNALED (status))
- {
- gdb_assert (num_lwps > 1);
-
- if (in_thread_list (lp->ptid))
- {
- /* Core GDB cannot deal with us deleting the current
- thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- printf_unfiltered ("[%s exited]\n",
- target_pid_to_str (lp->ptid));
- }
- if (debug_lin_lwp)
- fprintf_unfiltered (gdb_stdlog,
- "SWC: %s exited.\n",
- target_pid_to_str (lp->ptid));
-
- delete_lwp (lp->ptid);
- return 0;
- }
-
- /* Check if the current LWP has previously exited. For nptl threads,
- there is no exit signal issued for LWPs that are not the
- main thread so we should check whenever the thread is stopped. */
- if (!lin_lwp_thread_alive (lp->ptid))
- {
- if (in_thread_list (lp->ptid))
- {
- /* Core GDB cannot deal with us deleting the current
- thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- printf_unfiltered ("[%s exited]\n",
- target_pid_to_str (lp->ptid));
- }
- if (debug_lin_lwp)
- fprintf_unfiltered (gdb_stdlog,
- "SWC: %s already exited.\n",
- target_pid_to_str (lp->ptid));
-
- delete_lwp (lp->ptid);
- return 0;
- }
-
- gdb_assert (WIFSTOPPED (status));
+ status = wait_lwp (lp);
+ if (status == 0)
+ return 0;

/* Ignore any signals in FLUSH_MASK. */
if (flush_mask && sigismember (flush_mask, WSTOPSIG (status)))