diff options
Diffstat (limited to 'src/lib/err/backtrace.c')
| -rw-r--r-- | src/lib/err/backtrace.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/src/lib/err/backtrace.c b/src/lib/err/backtrace.c index c2011285c0..8bc7e6965c 100644 --- a/src/lib/err/backtrace.c +++ b/src/lib/err/backtrace.c @@ -57,7 +57,8 @@ #include "lib/err/torerr.h" #if defined(HAVE_EXECINFO_H) && defined(HAVE_BACKTRACE) && \ - defined(HAVE_BACKTRACE_SYMBOLS_FD) && defined(HAVE_SIGACTION) + defined(HAVE_BACKTRACE_SYMBOLS_FD) && defined(HAVE_SIGACTION) && \ + defined(HAVE_PTHREAD_H) #define USE_BACKTRACE #endif @@ -190,13 +191,15 @@ dump_stack_symbols_to_error_fds(void) backtrace_symbols_fd(cb_buf, (int)depth, fds[i]); } +/* The signals that we want our backtrace handler to trap */ +static int trap_signals[] = { SIGSEGV, SIGILL, SIGFPE, SIGBUS, SIGSYS, + SIGIO, -1 }; + /** Install signal handlers as needed so that when we crash, we produce a * useful stack trace. Return 0 on success, -errno on failure. */ static int install_bt_handler(void) { - int trap_signals[] = { SIGSEGV, SIGILL, SIGFPE, SIGBUS, SIGSYS, - SIGIO, -1 }; int i, rv=0; struct sigaction sa; @@ -232,6 +235,23 @@ install_bt_handler(void) static void remove_bt_handler(void) { + int i; + + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = SIG_DFL; + sigfillset(&sa.sa_mask); + + for (i = 0; trap_signals[i] >= 0; ++i) { + /* remove_bt_handler() is called on shutdown, from low-level code. + * It's not a fatal error, so we just ignore it. */ + (void)sigaction(trap_signals[i], &sa, NULL); + } + + /* cb_buf_mutex is statically initialised, so we can not destroy it. + * If we destroy it, and then re-initialise tor, all our backtraces will + * fail. */ } #endif /* defined(USE_BACKTRACE) */ |