+++ /dev/null
-Status: submitted for comments
-
-2004-11-12 Daniel Jacobowitz <dan@debian.org>
-
- * linux-nat.c (my_waitpid): New function.
- (linux_test_for_tracefork): Make more robust and verbose. Take
- an ORIGINAL_PID argument and test for PTRACE_SETOPTIONS first.
- (linux_supports_tracefork, linux_supports_tracevforkdone): Take a PID
- argument. Update calls to linux_test_for_tracefork.
- (linux_enable_event_reporting, child_follow_fork)
- (child_insert_fork_catchpoint, child_insert_vfork_catchpoint)
- (child_insert_exec_catchpoint): Update calls to
- linux_supports_tracefork and linux_supports_tracevforkdone.
-
-Index: gdb-6.3/gdb/linux-nat.c
-===================================================================
---- gdb-6.3.orig/gdb/linux-nat.c 2004-10-08 16:29:47.000000000 -0400
-+++ gdb-6.3/gdb/linux-nat.c 2004-11-13 16:41:51.368720845 -0500
-@@ -150,18 +150,47 @@ linux_tracefork_child (void)
- exit (0);
- }
-
--/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. We
-+/* Wrapper function for waitpid which handles EINTR. */
-+
-+static int
-+my_waitpid (int pid, int *status, int flags)
-+{
-+ int ret;
-+ do
-+ {
-+ ret = waitpid (pid, status, flags);
-+ }
-+ while (ret == -1 && errno == EINTR);
-+
-+ return ret;
-+}
-+
-+/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
-+
-+ First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
-+ we know that the feature is not available. This may change the tracing
-+ options for ORIGINAL_PID, but we'll be setting them shortly anyway.
-+
-+ However, if it succeeds, we don't know for sure that the feature is
-+ available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
- create a child process, attach to it, use PTRACE_SETOPTIONS to enable
-- fork tracing, and let it fork. If the process exits, we assume that
-- we can't use TRACEFORK; if we get the fork notification, and we can
-- extract the new child's PID, then we assume that we can. */
-+ fork tracing, and let it fork. If the process exits, we assume that we
-+ can't use TRACEFORK; if we get the fork notification, and we can extract
-+ the new child's PID, then we assume that we can. */
-
- static void
--linux_test_for_tracefork (void)
-+linux_test_for_tracefork (int original_pid)
- {
- int child_pid, ret, status;
- long second_pid;
-
-+ linux_supports_tracefork_flag = 0;
-+ linux_supports_tracevforkdone_flag = 0;
-+
-+ ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
-+ if (ret != 0)
-+ return;
-+
- child_pid = fork ();
- if (child_pid == -1)
- perror_with_name ("linux_test_for_tracefork: fork");
-@@ -169,7 +198,7 @@ linux_test_for_tracefork (void)
- if (child_pid == 0)
- linux_tracefork_child ();
-
-- ret = waitpid (child_pid, &status, 0);
-+ ret = my_waitpid (child_pid, &status, 0);
- if (ret == -1)
- perror_with_name ("linux_test_for_tracefork: waitpid");
- else if (ret != child_pid)
-@@ -177,13 +206,23 @@ linux_test_for_tracefork (void)
- if (! WIFSTOPPED (status))
- error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status);
-
-- linux_supports_tracefork_flag = 0;
--
- ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK);
- if (ret != 0)
- {
-- ptrace (PTRACE_KILL, child_pid, 0, 0);
-- waitpid (child_pid, &status, 0);
-+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
-+ if (ret != 0)
-+ {
-+ warning ("linux_test_for_tracefork: failed to kill child");
-+ return;
-+ }
-+
-+ ret = my_waitpid (child_pid, &status, 0);
-+ if (ret != child_pid)
-+ warning ("linux_test_for_tracefork: failed to wait for killed child");
-+ else if (!WIFSIGNALED (status))
-+ warning ("linux_test_for_tracefork: unexpected wait status 0x%x from "
-+ "killed child", status);
-+
- return;
- }
-
-@@ -192,8 +231,12 @@ linux_test_for_tracefork (void)
- PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
- linux_supports_tracevforkdone_flag = (ret == 0);
-
-- ptrace (PTRACE_CONT, child_pid, 0, 0);
-- ret = waitpid (child_pid, &status, 0);
-+ ret = ptrace (PTRACE_CONT, child_pid, 0, 0);
-+ if (ret != 0)
-+ warning ("linux_test_for_tracefork: failed to resume child");
-+
-+ ret = my_waitpid (child_pid, &status, 0);
-+
- if (ret == child_pid && WIFSTOPPED (status)
- && status >> 16 == PTRACE_EVENT_FORK)
- {
-@@ -204,34 +247,38 @@ linux_test_for_tracefork (void)
- int second_status;
-
- linux_supports_tracefork_flag = 1;
-- waitpid (second_pid, &second_status, 0);
-- ptrace (PTRACE_DETACH, second_pid, 0, 0);
-+ my_waitpid (second_pid, &second_status, 0);
-+ ret = ptrace (PTRACE_KILL, second_pid, 0, 0);
-+ if (ret != 0)
-+ warning ("linux_test_for_tracefork: failed to kill second child");
- }
- }
-+ else
-+ warning ("linux_test_for_tracefork: unexpected result from waitpid "
-+ "(%d, status 0x%x)", ret, status);
-
-- if (WIFSTOPPED (status))
-- {
-- ptrace (PTRACE_DETACH, child_pid, 0, 0);
-- waitpid (child_pid, &status, 0);
-- }
-+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
-+ if (ret != 0)
-+ warning ("linux_test_for_tracefork: failed to kill child");
-+ my_waitpid (child_pid, &status, 0);
- }
-
- /* Return non-zero iff we have tracefork functionality available.
- This function also sets linux_supports_tracefork_flag. */
-
- static int
--linux_supports_tracefork (void)
-+linux_supports_tracefork (int pid)
- {
- if (linux_supports_tracefork_flag == -1)
-- linux_test_for_tracefork ();
-+ linux_test_for_tracefork (pid);
- return linux_supports_tracefork_flag;
- }
-
- static int
--linux_supports_tracevforkdone (void)
-+linux_supports_tracevforkdone (int pid)
- {
- if (linux_supports_tracefork_flag == -1)
-- linux_test_for_tracefork ();
-+ linux_test_for_tracefork (pid);
- return linux_supports_tracevforkdone_flag;
- }
-
-@@ -242,12 +289,12 @@ linux_enable_event_reporting (ptid_t pti
- int pid = ptid_get_pid (ptid);
- int options;
-
-- if (! linux_supports_tracefork ())
-+ if (! linux_supports_tracefork (pid))
- return;
-
- options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC
- | PTRACE_O_TRACECLONE;
-- if (linux_supports_tracevforkdone ())
-+ if (linux_supports_tracevforkdone (pid))
- options |= PTRACE_O_TRACEVFORKDONE;
-
- /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
-@@ -308,7 +355,8 @@ child_follow_fork (int follow_child)
-
- if (has_vforked)
- {
-- if (linux_supports_tracevforkdone ())
-+ gdb_assert (linux_supports_tracefork_flag >= 0);
-+ if (linux_supports_tracevforkdone (0))
- {
- int status;
-
-@@ -476,7 +524,7 @@ linux_handle_extended_wait (int pid, int
- int
- child_insert_fork_catchpoint (int pid)
- {
-- if (! linux_supports_tracefork ())
-+ if (! linux_supports_tracefork (pid))
- error ("Your system does not support fork catchpoints.");
-
- return 0;
-@@ -485,7 +533,7 @@ child_insert_fork_catchpoint (int pid)
- int
- child_insert_vfork_catchpoint (int pid)
- {
-- if (!linux_supports_tracefork ())
-+ if (!linux_supports_tracefork (pid))
- error ("Your system does not support vfork catchpoints.");
-
- return 0;
-@@ -494,7 +542,7 @@ child_insert_vfork_catchpoint (int pid)
- int
- child_insert_exec_catchpoint (int pid)
- {
-- if (!linux_supports_tracefork ())
-+ if (!linux_supports_tracefork (pid))
- error ("Your system does not support exec catchpoints.");
-
- return 0;
projects / openwrt.git / blobdiff