Adds support for detection of running in death test child processes.

include/gtest/gtest-death-test.h

@@ -51,6 +51,17 @@ GTEST_DECLARE_string_(death_test_style);
 
 #if GTEST_HAS_DEATH_TEST
 
+namespace internal {
+
+// Returns a Boolean value indicating whether the caller is currently
+// executing in the context of the death test child process.  Tools such as
+// Valgrind heap checkers may need this to modify their behavior in death
+// tests.  IMPORTANT: This is an internal utility.  Using it may break the
+// implementation of death tests.  User code MUST NOT use it.
+GTEST_API_ bool InDeathTestChild();
+
+}  // namespace internal
+
 // The following macros are useful for writing death tests.
 
 // Here's what happens when an ASSERT_DEATH* or EXPECT_DEATH* is

src/gtest-death-test.cc

@@ -109,13 +109,42 @@ GTEST_DEFINE_string_(
     "Indicates the file, line number, temporal index of "
     "the single death test to run, and a file descriptor to "
     "which a success code may be sent, all separated by "
-    "colons.  This flag is specified if and only if the current "
+    "the '|' characters.  This flag is specified if and only if the current "
     "process is a sub-process launched for running a thread-safe "
     "death test.  FOR INTERNAL USE ONLY.");
 }  // namespace internal
 
 #if GTEST_HAS_DEATH_TEST
 
+namespace internal {
+
+// Valid only for fast death tests. Indicates the code is running in the
+// child process of a fast style death test.
+static bool g_in_fast_death_test_child = false;
+
+// Returns a Boolean value indicating whether the caller is currently
+// executing in the context of the death test child process.  Tools such as
+// Valgrind heap checkers may need this to modify their behavior in death
+// tests.  IMPORTANT: This is an internal utility.  Using it may break the
+// implementation of death tests.  User code MUST NOT use it.
+bool InDeathTestChild() {
+# if GTEST_OS_WINDOWS
+
+  // On Windows, death tests are thread-safe regardless of the value of the
+  // death_test_style flag.
+  return !GTEST_FLAG(internal_run_death_test).empty();
+
+# else
+
+  if (GTEST_FLAG(death_test_style) == "threadsafe")
+    return !GTEST_FLAG(internal_run_death_test).empty();
+  else
+    return g_in_fast_death_test_child;
+#endif
+}
+
+}  // namespace internal
+
 // ExitedWithCode constructor.
 ExitedWithCode::ExitedWithCode(int exit_code) : exit_code_(exit_code) {
 }
@@ -825,6 +854,7 @@ DeathTest::TestRole NoExecDeathTest::AssumeRole() {
     // Event forwarding to the listeners of event listener API mush be shut
     // down in death test subprocesses.
     GetUnitTestImpl()->listeners()->SuppressEventForwarding();
+    g_in_fast_death_test_child = true;
     return EXECUTE_TEST;
   } else {
     GTEST_DEATH_TEST_CHECK_SYSCALL_(close(pipe_fd[1]));

test/gtest-death-test_test.cc

@@ -75,6 +75,7 @@ using testing::internal::DeathTestFactory;
 using testing::internal::FilePath;
 using testing::internal::GetLastErrnoDescription;
 using testing::internal::GetUnitTestImpl;
+using testing::internal::InDeathTestChild;
 using testing::internal::ParseNaturalNumber;
 using testing::internal::String;
 
@@ -1345,6 +1346,26 @@ TEST(ConditionalDeathMacrosSyntaxDeathTest, SwitchStatement) {
 #endif  // _MSC_VER
 }
 
+TEST(InDeathTestChildDeathTest, ReportsDeathTestCorrectlyInFastStyle) {
+  testing::GTEST_FLAG(death_test_style) = "fast";
+  EXPECT_FALSE(InDeathTestChild());
+  EXPECT_DEATH({
+    fprintf(stderr, InDeathTestChild() ? "Inside" : "Outside");
+    fflush(stderr);
+    _exit(1);
+  }, "Inside");
+}
+
+TEST(InDeathTestChildDeathTest, ReportsDeathTestCorrectlyInThreadSafeStyle) {
+  testing::GTEST_FLAG(death_test_style) = "threadsafe";
+  EXPECT_FALSE(InDeathTestChild());
+  EXPECT_DEATH({
+    fprintf(stderr, InDeathTestChild() ? "Inside" : "Outside");
+    fflush(stderr);
+    _exit(1);
+  }, "Inside");
+}
+
 // Tests that a test case whose name ends with "DeathTest" works fine
 // on Windows.
 TEST(NotADeathTest, Test) {