diff options
| author | Bruno Haible <bruno@clisp.org> | 2019-03-19 23:34:47 +0100 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2019-03-19 23:34:47 +0100 |
| commit | 4a7bec23342ecb43d6e367ed43d067e2a0507f6d (patch) | |
| tree | edb976c5082002583b5c6e77a8d6121d82ae60ec | |
| parent | cf8abf91bee57994da2b891077e6c7d4fb113445 (diff) | |
| download | gnulib-4a7bec23342ecb43d6e367ed43d067e2a0507f6d.tar.gz | |
c-stack: Make signal handlers more reliable.
* lib/c-stack.c (progname): New variable.
(die): Use it.
(c_stack_action): Initialize it.
(segv_handler): Save and restore errno.
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | lib/c-stack.c | 8 |
2 files changed, 15 insertions, 1 deletions
@@ -1,5 +1,13 @@ 2019-03-19 Bruno Haible <bruno@clisp.org> + c-stack: Make signal handlers more reliable. + * lib/c-stack.c (progname): New variable. + (die): Use it. + (c_stack_action): Initialize it. + (segv_handler): Save and restore errno. + +2019-03-19 Bruno Haible <bruno@clisp.org> + Help making signal handlers more reliable. * m4/gnulib-common.m4 (gl_COMMON_BODY): Emit definition of _GL_ASYNC_SAFE into config.h. diff --git a/lib/c-stack.c b/lib/c-stack.c index 929bb3a315..f50a4a5dc9 100644 --- a/lib/c-stack.c +++ b/lib/c-stack.c @@ -107,6 +107,8 @@ static char const * volatile stack_overflow_message; appears to have been a stack overflow, or with a core dump otherwise. This function is async-signal-safe. */ +static char const * volatile progname; + static _GL_ASYNC_SAFE _Noreturn void die (int signo) { @@ -119,7 +121,7 @@ die (int signo) #endif /* !SIGINFO_WORKS && !HAVE_LIBSIGSEGV */ segv_action (signo); message = signo ? program_error_message : stack_overflow_message; - ignore_value (write (STDERR_FILENO, getprogname (), strlen (getprogname ()))); + ignore_value (write (STDERR_FILENO, progname, strlen (progname))); ignore_value (write (STDERR_FILENO, ": ", 2)); ignore_value (write (STDERR_FILENO, message, strlen (message))); ignore_value (write (STDERR_FILENO, "\n", 1)); @@ -170,8 +172,10 @@ segv_handler (void *address _GL_UNUSED, int serious) # if DEBUG { char buf[1024]; + int saved_errno = errno; sprintf (buf, "segv_handler serious=%d\n", serious); write (STDERR_FILENO, buf, strlen (buf)); + errno = saved_errno; } # endif @@ -206,6 +210,7 @@ c_stack_action (_GL_ASYNC_SAFE void (*action) (int)) segv_action = action ? action : null_action; program_error_message = _("program error"); stack_overflow_message = _("stack overflow"); + progname = getprogname (); /* Always install the overflow handler. */ if (stackoverflow_install_handler (overflow_handler, @@ -298,6 +303,7 @@ c_stack_action (_GL_ASYNC_SAFE void (*action) (int)) segv_action = action ? action : null_action; program_error_message = _("program error"); stack_overflow_message = _("stack overflow"); + progname = getprogname (); sigemptyset (&act.sa_mask); |