diff options
| -rwxr-xr-x | configure | 27 | ||||
| -rw-r--r-- | unix.c | 81 |
2 files changed, 103 insertions, 5 deletions
@@ -484,6 +484,16 @@ int main() } ' +BACKTRACE_TESTCODE=' +#include <execinfo.h> + +int main() +{ + void *trace[16]; + return backtrace(trace, 16); +} +' + detect_resolv_dynamic() { case "$arch" in @@ -581,6 +591,19 @@ detect_nameser_has_ns_types() return $ret } +detect_backtrace() +{ + TMPFILE=$(mktemp /tmp/bitlbee-configure.XXXXXX) + ret=1 + echo "$BACKTRACE_TESTCODE" | $CC -o $TMPFILE -x c - >/dev/null 2>/dev/null + if [ "$?" = "0" ]; then + ret=0 + fi + + rm -f $TMPFILE + return $ret +} + if [ "$ssl" = "auto" ]; then detect_gnutls if [ "$ret" = "0" ]; then @@ -646,6 +669,10 @@ else echo 'Insufficient resolv routines. Jabber server must be set explicitly' fi +if detect_backtrace; then + echo '#define HAVE_BACKTRACE' >> config.h + echo '#define CRASHFILE "'$config'crash.log"' >> config.h +fi STORAGES="xml" @@ -45,6 +45,10 @@ #include "otr.h" #endif +#ifdef HAVE_BACKTRACE +#include <execinfo.h> +#endif + global_t global; /* Against global namespace pollution */ static struct { @@ -62,6 +66,9 @@ int main(int argc, char *argv[]) int i = 0; char *old_cwd = NULL; struct sigaction sig, old; +#ifdef HAVE_BACKTRACE + void *unused[1]; +#endif /* Required to make iconv to ASCII//TRANSLIT work. This makes BitlBee system-locale-sensitive. :-( */ @@ -175,6 +182,13 @@ int main(int argc, char *argv[]) sigaction(SIGINT, &sig, &old); sigaction(SIGTERM, &sig, &old); +#ifdef HAVE_BACKTRACE + /* As per the backtrace(3) man page, call this outside of the signal + * handler once to ensure any dynamic libraries are loaded in an + * async-signal-safe environment to prevent deadlocks */ + backtrace(unused, 1); +#endif + if (!getuid() || !geteuid()) { log_message(LOGLVL_WARNING, "BitlBee is running with root privileges. Why?"); } @@ -291,25 +305,82 @@ static void sighandler_shutdown(int signal) unused = write(shutdown_pipe.fd[1], "", 1); } +#ifdef HAVE_BACKTRACE +/* Writes a backtrace to (usually) /var/lib/bitlbee/crash.log + * No malloc allowed means not a lot can be written to that file */ +static void sighandler_crash_backtrace() +{ + int fd, mapsfd; + int size; + void *trace[128]; + const char message[] = "## " PACKAGE " crashed\n" + "## Version: " BITLBEE_VERSION "\n" + "## Configure args: " BITLBEE_CONFIGURE_ARGS "\n" + "##\n" + "## Backtrace:\n\n"; + const char message2[] = "\n" + "## Hint: To get details on addresses use\n" + "## addr2line -e <binary> <address>\n" + "## or\n" + "## gdb <binary> -ex 'l *<address>' -ex q\n" + "## where <binary> is a filename from above and <address> is the part between (...)\n" + "##\n\n"; + const char message3[] = "\n## End of memory maps. See above for the backtrace\n\n"; + + fd = open(CRASHFILE, O_WRONLY | O_APPEND | O_CREAT, 0600); + + if (fd == -1 || write(fd, message, sizeof(message) - 1) == -1) { + return; + } + + size = backtrace(trace, 128); + backtrace_symbols_fd(trace, size, fd); + + (void) write(fd, message2, sizeof(message2) - 1); + + /* a bit too linux-specific, so fail gracefully */ + mapsfd = open("/proc/self/maps", O_RDONLY, 0); + + if (mapsfd != -1) { + char buf[4096] = {0}; + ssize_t bytes; + + while ((bytes = read(mapsfd, buf, sizeof(buf))) > 0) { + (void) write(fd, buf, bytes); + } + (void) close(mapsfd); + (void) write(fd, message3, sizeof(message3) - 1); + } + + (void) close(fd); +} +#endif + /* Signal handler for SIGSEGV * A desperate attempt to tell the user that everything is wrong in the world. * Avoids using irc_abort() because it has several unsafe calls to malloc */ static void sighandler_crash(int signal) { GSList *l; - int unused G_GNUC_UNUSED; - const char *message = "ERROR :BitlBee crashed! (SIGSEGV received)\r\n"; - int len = strlen(message); + const char message[] = "ERROR :BitlBee crashed! (SIGSEGV received)\r\n" +#ifdef HAVE_BACKTRACE + "ERROR :Writing backtrace to " CRASHFILE "\r\n" +#endif + "ERROR :This is a bug either in BitlBee or a plugin, ask us on IRC if unsure\r\n"; for (l = irc_connection_list; l; l = l->next) { irc_t *irc = l->data; sock_make_blocking(irc->fd); if (irc->sendbuffer) { - unused = write(irc->fd, irc->sendbuffer, strlen(irc->sendbuffer)); + (void) write(irc->fd, irc->sendbuffer, strlen(irc->sendbuffer)); } - unused = write(irc->fd, message, len); + (void) write(irc->fd, message, sizeof(message) - 1); } +#ifdef HAVE_BACKTRACE + sighandler_crash_backtrace(); +#endif + raise(signal); } |