From 1a0c76fa55e46c7caf0f9af53299524963e52382 Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Tue, 16 Jul 2013 11:28:04 +0000
Subject: [PATCH] tsan: support sigsuspend() call Intercepting it makes it
 process pending signal before return.

llvm-svn: 186400
---
 compiler-rt/lib/tsan/lit_tests/sigsuspend.cc  | 38 +++++++++++++++++++++++++++
 compiler-rt/lib/tsan/rtl/tsan_interceptors.cc |  6 +++++
 compiler-rt/lib/tsan/rtl/tsan_stat.cc         |  1 +
 compiler-rt/lib/tsan/rtl/tsan_stat.h          |  1 +
 4 files changed, 46 insertions(+)
 create mode 100644 compiler-rt/lib/tsan/lit_tests/sigsuspend.cc

diff --git a/compiler-rt/lib/tsan/lit_tests/sigsuspend.cc b/compiler-rt/lib/tsan/lit_tests/sigsuspend.cc
new file mode 100644
index 0000000..4da20a6
--- /dev/null
+++ b/compiler-rt/lib/tsan/lit_tests/sigsuspend.cc
@@ -0,0 +1,38 @@
+// RUN: %clangxx_tsan -O1 %s -o %t && %t 2>&1 | FileCheck %s
+#include <assert.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdio.h>
+
+static bool signal_handler_ran = false;
+
+void do_nothing_signal_handler(int signum) {
+  write(1, "HANDLER\n", 8);
+  signal_handler_ran = true;
+}
+
+int main() {
+  const int kSignalToTest = SIGSYS;
+  assert(SIG_ERR != signal(kSignalToTest, do_nothing_signal_handler));
+  sigset_t empty_set;
+  assert(0 == sigemptyset(&empty_set));
+  sigset_t one_signal = empty_set;
+  assert(0 == sigaddset(&one_signal, kSignalToTest));
+  sigset_t old_set;
+  assert(0 == sigprocmask(SIG_BLOCK, &one_signal, &old_set));
+  raise(kSignalToTest);
+  assert(!signal_handler_ran);
+  sigset_t all_but_one;
+  assert(0 == sigfillset(&all_but_one));
+  assert(0 == sigdelset(&all_but_one, kSignalToTest));
+  sigsuspend(&all_but_one);
+  assert(signal_handler_ran);
+
+  // Restore the original set.
+  assert(0 == sigprocmask(SIG_SETMASK, &old_set, NULL));
+  printf("DONE");
+}
+
+// CHECK: HANDLER
+// CHECK: DONE
diff --git a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
index 35a582c..92d8ae1 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
@@ -1707,6 +1707,11 @@ TSAN_INTERCEPTOR(sighandler_t, signal, int sig, sighandler_t h) {
   return old.sa_handler;
 }
 
+TSAN_INTERCEPTOR(int, sigsuspend, const sigset_t *mask) {
+  SCOPED_TSAN_INTERCEPTOR(sigsuspend, mask);
+  return REAL(sigsuspend)(mask);
+}
+
 TSAN_INTERCEPTOR(int, raise, int sig) {
   SCOPED_TSAN_INTERCEPTOR(raise, sig);
   SignalContext *sctx = SigCtx(thr);
@@ -2071,6 +2076,7 @@ void InitializeInterceptors() {
 
   TSAN_INTERCEPT(sigaction);
   TSAN_INTERCEPT(signal);
+  TSAN_INTERCEPT(sigsuspend);
   TSAN_INTERCEPT(raise);
   TSAN_INTERCEPT(kill);
   TSAN_INTERCEPT(pthread_kill);
diff --git a/compiler-rt/lib/tsan/rtl/tsan_stat.cc b/compiler-rt/lib/tsan/rtl/tsan_stat.cc
index 3f153b6..5e8cc18 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_stat.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_stat.cc
@@ -257,6 +257,7 @@ void StatOutput(u64 *stat) {
   name[StatInt_poll]                     = "  poll                            ";
   name[StatInt_sigaction]                = "  sigaction                       ";
   name[StatInt_signal]                   = "  signal                          ";
+  name[StatInt_sigsuspend]               = "  sigsuspend                      ";
   name[StatInt_raise]                    = "  raise                           ";
   name[StatInt_kill]                     = "  kill                            ";
   name[StatInt_pthread_kill]             = "  pthread_kill                    ";
diff --git a/compiler-rt/lib/tsan/rtl/tsan_stat.h b/compiler-rt/lib/tsan/rtl/tsan_stat.h
index 36b298e..6131721 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_stat.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_stat.h
@@ -252,6 +252,7 @@ enum StatType {
   StatInt_poll,
   StatInt_sigaction,
   StatInt_signal,
+  StatInt_sigsuspend,
   StatInt_raise,
   StatInt_kill,
   StatInt_pthread_kill,
-- 
2.7.4