SERVER-12259 Make custom signal handlers defer to default behavior rather than calling quickExit.

On systems with good support for POSIX signals, by configuring the MongoDB
custom signal handlers to automatically reset to the default handler when
executing, and to re-raise fatal signals at the end of the custom handler
instead of calling quickExit, we can get proper OS behavior for core dumping and
exiting with signal codes.

1 files changed, 103 insertions, 0 deletions

diff --git a/src/mongo/util/signal_handlers_synchronous_test.cpp b/src/mongo/util/signal_handlers_synchronous_test.cpp
new file mode 100644
index 00000000000..f4104bafa16
--- /dev/null
+++ b/src/mongo/util/signal_handlers_synchronous_test.cpp
@@ -0,0 +1,103 @@
+/**
+ *    Copyright (C) 2015 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kDefault
+
+#include "mongo/platform/basic.h"
+
+#include <cmath>
+#include <cstdlib>
+#include <csignal>
+
+#include "mongo/unittest/unittest.h"
+#include "mongo/unittest/death_test.h"
+#include "mongo/util/signal_handlers_synchronous.h"
+
+namespace {
+using namespace mongo;
+
+// Tests of signals that should be ignored raise each signal twice, to ensure that the handler isn't
+// reset.
+#define IGNORED_SIGNAL(SIGNUM)           \
+    TEST(IgnoredSignalTest, SIGNUM##_) { \
+        ASSERT_EQ(0, raise(SIGNUM));     \
+        ASSERT_EQ(0, raise(SIGNUM));     \
+    }
+
+#define FATAL_SIGNAL(SIGNUM)                                                                   \
+    DEATH_TEST(FatalSignalTest, SIGNUM##_, str::stream() << "Got signal: " << SIGNUM << " ") { \
+        ASSERT_EQ(0, raise(SIGNUM));                                                           \
+    }
+
+IGNORED_SIGNAL(SIGUSR2)
+IGNORED_SIGNAL(SIGHUP)
+IGNORED_SIGNAL(SIGPIPE)
+FATAL_SIGNAL(SIGQUIT)
+FATAL_SIGNAL(SIGABRT)
+FATAL_SIGNAL(SIGFPE)
+FATAL_SIGNAL(SIGILL)
+
+#if not defined(__has_feature)
+#define __has_feature(X) 0
+#endif
+
+#if !__has_feature(address_sanitizer)
+// These signals trip the leak sanitizer
+FATAL_SIGNAL(SIGSEGV)
+FATAL_SIGNAL(SIGBUS)
+#endif
+
+DEATH_TEST(FatalTerminateTest,
+           TerminateIsFatalWithoutException,
+           "terminate() called. No exception") {
+    std::terminate();
+}
+
+DEATH_TEST(FatalTerminateTest,
+           TerminateIsFatalWithDBException,
+           " terminate() called. An exception is active") {
+    try {
+        uasserted(28720, "Fatal DBException occurrence");
+    } catch (...) {
+        std::terminate();
+    }
+}
+
+DEATH_TEST(FatalTerminateTest,
+           TerminateIsFatalWithDoubleException,
+           "terminate() called. An exception is active") {
+    class ThrowInDestructor {
+    public:
+        ~ThrowInDestructor() {
+            uasserted(28721, "Fatal second exception");
+        }
+    } tid;
+    uasserted(28719, "Non-fatal first exception");
+}
+
+}  // namespace