1 files changed, 27 insertions, 7 deletions
diff --git a/test/core/util/test_config.c b/test/core/util/test_config.c
index 30caf4b1ef..84b376ad3e 100644
--- a/test/core/util/test_config.c
+++ b/test/core/util/test_config.c
@@ -35,6 +35,7 @@
 
 #include <grpc/support/port_platform.h>
 #include <grpc/support/log.h>
+#include "src/core/support/string.h"
 #include <stdlib.h>
 #include <signal.h>
 
@@ -88,25 +89,43 @@ static void install_crash_handler() {
 #include <stdio.h>
 #include <string.h>
 #include <grpc/support/useful.h>
+#include <errno.h>
 
 static char g_alt_stack[MINSIGSTKSZ];
 
 #define MAX_FRAMES 32
 
+/* signal safe output */
+static void output_string(const char *string) {
+  size_t len = strlen(string);
+  ssize_t r;
+
+  do {
+    r = write(STDERR_FILENO, string, len);
+  } while (r == -1 && errno == EINTR);
+}
+
+static void output_num(long num) {
+  char buf[GPR_LTOA_MIN_BUFSIZE];
+  gpr_ltoa(num, buf);
+  output_string(buf);
+}
+
 static void crash_handler(int signum, siginfo_t *info, void *data) {
   void *addrlist[MAX_FRAMES + 1];
   int addrlen;
-  int i;
-  char **symlist;
 
-  fprintf(stderr, "Caught signal %d\n", signum);
+  output_string("\n\n\n*******************************\nCaught signal ");
+  output_num(signum);
+  output_string("\n");
+
   addrlen = backtrace(addrlist, GPR_ARRAY_SIZE(addrlist));
 
-  symlist = backtrace_symbols(addrlist, addrlen);
-  for (i = 0; i < addrlen; i++) {
-    fprintf(stderr, "  %s\n", symlist[i]);
+  if (addrlen == 0) {
+    output_string("  no backtrace\n");
+  } else {
+    backtrace_symbols_fd(addrlist, addrlen, STDERR_FILENO);
   }
-  free(symlist);
 
   raise(signum);
 }
@@ -114,6 +133,7 @@ static void crash_handler(int signum, siginfo_t *info, void *data) {
 static void install_crash_handler() {
   stack_t ss;
   struct sigaction sa;
+
   memset(&ss, 0, sizeof(ss));
   memset(&sa, 0, sizeof(sa));
   ss.ss_size = sizeof(g_alt_stack);