commit bb15dc1ebd520cb902124c982abbba135af183b5 Author: Nick Mathewson nickm@torproject.org Date: Wed Jun 20 14:04:03 2018 -0400
Allow raw_assert() to dump stack traces.
It doesn't do this as beautifully as tor_assert(), but it doesn't depend on any higher-level code. --- src/common/backtrace.c | 20 ++++++++++++++++++++ src/common/backtrace.h | 1 + src/common/torerr.c | 3 +++ 3 files changed, 24 insertions(+)
diff --git a/src/common/backtrace.c b/src/common/backtrace.c index af939b0a8..d83cbba0e 100644 --- a/src/common/backtrace.c +++ b/src/common/backtrace.c @@ -167,6 +167,21 @@ crash_handler(int sig, siginfo_t *si, void *ctx_) abort(); }
+/** Write a backtrace to all of the emergency-error fds. */ +void +dump_stack_symbols_to_error_fds(void) +{ + int n_fds, i; + const int *fds = NULL; + size_t depth; + + depth = backtrace(cb_buf, MAX_DEPTH); + + n_fds = tor_log_get_sigsafe_err_fds(&fds); + for (i=0; i < n_fds; ++i) + backtrace_symbols_fd(cb_buf, (int)depth, fds[i]); +} + /** 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 @@ -234,6 +249,11 @@ static void remove_bt_handler(void) { } + +void +dump_stack_symbols_to_error_fds(void) +{ +} #endif /* defined(NO_BACKTRACE_IMPL) */
/** Set up code to handle generating error messages on crashes. */ diff --git a/src/common/backtrace.h b/src/common/backtrace.h index 7182aeb07..0a145fc92 100644 --- a/src/common/backtrace.h +++ b/src/common/backtrace.h @@ -14,6 +14,7 @@ void log_backtrace_impl(int severity, int domain, const char *msg, tor_log_fn logger); int configure_backtrace_handler(const char *tor_version); void clean_up_backtrace_handler(void); +void dump_stack_symbols_to_error_fds(void);
#define log_backtrace(sev, dom, msg) \ log_backtrace_impl((sev), (dom), (msg), tor_log) diff --git a/src/common/torerr.c b/src/common/torerr.c index c22526254..5dbdc629a 100644 --- a/src/common/torerr.c +++ b/src/common/torerr.c @@ -29,6 +29,7 @@ #endif
#include "common/torerr.h" +#include "common/backtrace.h"
/** Array of fds to log crash-style warnings to. */ static int sigsafe_log_fds[TOR_SIGSAFE_LOG_MAX_FDS] = { STDERR_FILENO }; @@ -140,6 +141,8 @@ tor_raw_assertion_failed_msg_(const char *file, int line, const char *expr, tor_log_err_sigsafe_write(msg); tor_log_err_sigsafe_write("\n"); } + + dump_stack_symbols_to_error_fds(); }
/* As format_{hex,dex}_number_sigsafe, but takes a <b>radix</b> argument