1 files changed, 193 insertions, 0 deletions
diff --git a/src/third_party/unwind/dist/tests/test-async-sig.c b/src/third_party/unwind/dist/tests/test-async-sig.c
new file mode 100644
index 00000000000..2ce8b4bb711
--- /dev/null
+++ b/src/third_party/unwind/dist/tests/test-async-sig.c
@@ -0,0 +1,193 @@
+/* libunwind - a platform-independent unwind library
+   Copyright (C) 2004 Hewlett-Packard Co
+	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
+
+/* Check whether basic unwinding truly is async-signal safe.  */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "compiler.h"
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/time.h>
+
+#define UNW_LOCAL_ONLY
+#include <libunwind.h>
+
+static const int nerrors_max = 100;
+
+struct itimerval interval =
+  {
+    .it_interval = { .tv_sec = 0, .tv_usec = 0 },
+    .it_value    = { .tv_sec = 0, .tv_usec = 1000 }
+  };
+
+int verbose;
+int nerrors;
+int sigcount;
+
+#ifndef CONFIG_BLOCK_SIGNALS
+/* When libunwind is configured with --enable-block-signals=no, the caller
+   is responsible for preventing recursion via signal handlers.
+   We use a simple global here.  In a multithreaded program, one would use
+   a thread-local variable.  */
+int recurcount;
+#endif
+
+#define panic(args...)					\
+	{ ++nerrors; fprintf (stderr, args); return; }
+
+static void
+do_backtrace (int may_print, int get_proc_name)
+{
+  char buf[512], name[256];
+  unw_cursor_t cursor;
+  unw_word_t ip, sp, off;
+  unw_context_t uc;
+  int ret;
+  int depth = 0;
+
+#ifndef CONFIG_BLOCK_SIGNALS
+  if (recurcount > 0)
+    return;
+  recurcount += 1;
+#endif
+
+  unw_getcontext (&uc);
+  if (unw_init_local (&cursor, &uc) < 0)
+    panic ("unw_init_local failed!\n");
+
+  do
+    {
+      unw_get_reg (&cursor, UNW_REG_IP, &ip);
+      unw_get_reg (&cursor, UNW_REG_SP, &sp);
+
+      buf[0] = '\0';
+      if (get_proc_name || (may_print && verbose))
+	{
+	  ret = unw_get_proc_name (&cursor, name, sizeof (name), &off);
+	  if (ret == 0 && (may_print && verbose))
+	    {
+	      if (off)
+		snprintf (buf, sizeof (buf), "<%s+0x%lx>", name, (long) off);
+	      else
+		{
+		  size_t len = strlen (name);
+		  buf[0] = '<';
+		  memcpy (buf + 1, name, len);
+		  buf[len + 1] = '>';
+		  buf[len + 2] = '\0';
+		}
+	    }
+	}
+
+      if (may_print && verbose)
+	printf ("%016lx %-32s (sp=%016lx)\n", (long) ip, buf, (long) sp);
+
+      ret = unw_step (&cursor);
+      if (ret < 0)
+	{
+	  unw_get_reg (&cursor, UNW_REG_IP, &ip);
+	  panic ("FAILURE: unw_step() returned %d for ip=%lx\n",
+		 ret, (long) ip);
+	}
+      if (depth++ > 100)
+        {
+	  panic ("FAILURE: unw_step() looping over %d iterations\n", depth);
+	  break;
+        }
+    }
+  while (ret > 0);
+
+#ifndef CONFIG_BLOCK_SIGNALS
+  recurcount -= 1;
+#endif
+}
+
+void
+sighandler (int signal)
+{
+  if (verbose)
+    printf ("sighandler(signal=%d, count=%d)\n", signal, sigcount);
+
+  do_backtrace (1, 1);
+
+  ++sigcount;
+
+  if (sigcount == 100)
+    unw_set_caching_policy (unw_local_addr_space, UNW_CACHE_GLOBAL);
+  else if (sigcount == 200)
+    unw_set_caching_policy (unw_local_addr_space, UNW_CACHE_PER_THREAD);
+  else if (sigcount == 300 || nerrors > nerrors_max)
+    {
+      if (nerrors > nerrors_max)
+        panic ("Too many errors (%d)\n", nerrors);
+      if (nerrors)
+	{
+	  fprintf (stderr, "FAILURE: detected %d errors\n", nerrors);
+	  exit (-1);
+	}
+      if (verbose)
+	printf ("SUCCESS.\n");
+      exit (0);
+    }
+  setitimer (ITIMER_VIRTUAL, &interval, NULL);
+}
+
+int
+main (int argc, char **argv UNUSED)
+{
+  struct sigaction act;
+  long i = 0;
+
+  if (argc > 1)
+    verbose = 1;
+
+  unw_set_caching_policy (unw_local_addr_space, UNW_CACHE_NONE);
+
+  memset (&act, 0, sizeof (act));
+  act.sa_handler = sighandler;
+  act.sa_flags = SA_SIGINFO;
+  sigaction (SIGVTALRM, &act, NULL);
+
+  setitimer (ITIMER_VIRTUAL, &interval, NULL);
+
+  while (1)
+    {
+      if (0 && verbose)
+	printf ("%s: starting backtrace\n", __FUNCTION__);
+      do_backtrace (0, (i++ % 100) == 0);
+      if (nerrors > nerrors_max)
+        {
+	  fprintf (stderr, "Too many errors (%d)\n", nerrors);
+	  exit (-1);
+        }
+    }
+  return (0);
+}