Fix signal chain to allow for signal() call to be used
Bug: 17320614
Change-Id: Ia917307fb1b593644f524518e11e295b3c64be01
diff --git a/sigchainlib/sigchain.cc b/sigchainlib/sigchain.cc
index c655226..50bfe70 100644
--- a/sigchainlib/sigchain.cc
+++ b/sigchainlib/sigchain.cc
@@ -34,7 +34,7 @@
class SignalAction {
public:
- SignalAction() : claimed_(false) {
+ SignalAction() : claimed_(false), uses_old_style_(false) {
}
// Claim the signal and keep the action specified.
@@ -60,13 +60,22 @@
}
// Change the recorded action to that specified.
- void SetAction(const struct sigaction& action) {
+ // If oldstyle is true then this action is from an older style signal()
+ // call as opposed to sigaction(). In this case the sa_handler is
+ // used when invoking the user's handler.
+ void SetAction(const struct sigaction& action, bool oldstyle) {
action_ = action;
+ uses_old_style_ = oldstyle;
+ }
+
+ bool OldStyle() const {
+ return uses_old_style_;
}
private:
struct sigaction action_; // Action to be performed.
bool claimed_; // Whether signal is claimed or not.
+ bool uses_old_style_; // Action is created using signal(). Use sa_handler.
};
// User's signal handlers
@@ -115,7 +124,7 @@
}
const struct sigaction& action = user_sigactions[sig].GetAction();
- if ((action.sa_flags & SA_SIGINFO) == 0) {
+ if (user_sigactions[sig].OldStyle()) {
if (action.sa_handler != NULL) {
action.sa_handler(sig);
} else {
@@ -145,7 +154,7 @@
*old_action = user_sigactions[signal].GetAction();
}
if (new_action != NULL) {
- user_sigactions[signal].SetAction(*new_action);
+ user_sigactions[signal].SetAction(*new_action, false);
}
return 0;
}
@@ -168,6 +177,45 @@
return linked_sigaction(signal, new_action, old_action);
}
+sighandler_t signal(int signal, sighandler_t handler) {
+ struct sigaction sa;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_handler = handler;
+ sa.sa_flags = SA_RESTART;
+ sighandler_t oldhandler;
+
+ // If this signal has been claimed as a signal chain, record the user's
+ // action but don't pass it on to the kernel.
+ // Note that we check that the signal number is in range here. An out of range signal
+ // number should behave exactly as the libc sigaction.
+ if (signal > 0 && signal < _NSIG && user_sigactions[signal].IsClaimed()) {
+ oldhandler = reinterpret_cast<sighandler_t>(user_sigactions[signal].GetAction().sa_handler);
+ user_sigactions[signal].SetAction(sa, true);
+ return oldhandler;
+ }
+
+ // Will only get here if the signal chain has not been claimed. We want
+ // to pass the sigaction on to the kernel via the real sigaction in libc.
+
+ void* linked_sigaction_sym = dlsym(RTLD_NEXT, "sigaction");
+ if (linked_sigaction_sym == nullptr) {
+ linked_sigaction_sym = dlsym(RTLD_DEFAULT, "sigaction");
+ if (linked_sigaction_sym == nullptr ||
+ linked_sigaction_sym == reinterpret_cast<void*>(sigaction)) {
+ log("Unable to find next sigaction in signal chain");
+ abort();
+ }
+ }
+
+ typedef int (*SigAction)(int, const struct sigaction*, struct sigaction*);
+ SigAction linked_sigaction = reinterpret_cast<SigAction>(linked_sigaction_sym);
+ if (linked_sigaction(signal, &sa, &sa) == -1) {
+ return SIG_ERR;
+ }
+
+ return reinterpret_cast<sighandler_t>(sa.sa_handler);
+}
+
int sigprocmask(int how, const sigset_t* bionic_new_set, sigset_t* bionic_old_set) {
const sigset_t* new_set_ptr = bionic_new_set;
sigset_t tmpset;
diff --git a/test/004-SignalTest/signaltest.cc b/test/004-SignalTest/signaltest.cc
index f09fc26..a6d9b66 100644
--- a/test/004-SignalTest/signaltest.cc
+++ b/test/004-SignalTest/signaltest.cc
@@ -87,12 +87,12 @@
// Prevent the compiler being a smart-alec and optimizing out the assignment
// to nullptr.
-char *p = nullptr;
+char *go_away_compiler = nullptr;
extern "C" JNIEXPORT jint JNICALL Java_Main_testSignal(JNIEnv*, jclass) {
#if defined(__arm__) || defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
// On supported architectures we cause a real SEGV.
- *p = 'a';
+ *go_away_compiler = 'a';
#else
// On other architectures we simulate SEGV.
kill(getpid(), SIGSEGV);
diff --git a/test/004-SignalTest2/expected.txt b/test/004-SignalTest2/expected.txt
new file mode 100644
index 0000000..fd5ec00
--- /dev/null
+++ b/test/004-SignalTest2/expected.txt
@@ -0,0 +1,5 @@
+init signal test
+Caught NullPointerException
+Caught StackOverflowError
+signal caught
+Signal test OK
diff --git a/test/004-SignalTest2/info.txt b/test/004-SignalTest2/info.txt
new file mode 100644
index 0000000..00b0d9a
--- /dev/null
+++ b/test/004-SignalTest2/info.txt
@@ -0,0 +1 @@
+Imported from oat tests.
diff --git a/test/004-SignalTest2/signaltest.cc b/test/004-SignalTest2/signaltest.cc
new file mode 100644
index 0000000..47b1eb6
--- /dev/null
+++ b/test/004-SignalTest2/signaltest.cc
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "jni.h"
+
+#include <sys/ucontext.h>
+
+static int signal_count;
+static const int kMaxSignal = 2;
+
+static void signalhandler(int sig) {
+ printf("signal caught\n");
+ ++signal_count;
+ if (signal_count > kMaxSignal) {
+ printf("too many signals\n");
+ abort();
+ }
+ printf("Signal test OK\n");
+ exit(0);
+}
+
+sighandler_t oldsignal;
+
+extern "C" JNIEXPORT void JNICALL Java_Main_initSignalTest2(JNIEnv*, jclass) {
+ oldsignal = signal(SIGSEGV, reinterpret_cast<sighandler_t>(signalhandler));
+}
+
+// Prevent the compiler being a smart-alec and optimizing out the assignment
+// to nullptr.
+char *go_away_compiler2 = nullptr;
+
+extern "C" JNIEXPORT void JNICALL Java_Main_testSignal2(JNIEnv*, jclass) {
+ *go_away_compiler2 = 'a';
+}
+
diff --git a/test/004-SignalTest2/src/Main.java b/test/004-SignalTest2/src/Main.java
new file mode 100644
index 0000000..7799e8c
--- /dev/null
+++ b/test/004-SignalTest2/src/Main.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class Main {
+ private static native void initSignalTest2();
+ private static native void testSignal2();
+
+ private static void stackOverflow() {
+ stackOverflow();
+ }
+
+ public static void main(String[] args) {
+ System.loadLibrary("arttest");
+
+ System.out.println("init signal test");
+ initSignalTest2();
+ try {
+ Object o = null;
+ int hash = o.hashCode();
+
+ // Should never get here.
+ System.out.println("hash: " + hash);
+ throw new AssertionError();
+ } catch (NullPointerException e) {
+ System.out.println("Caught NullPointerException");
+ }
+ try {
+ stackOverflow();
+
+ // Should never get here.
+ throw new AssertionError();
+ } catch (StackOverflowError e) {
+ System.out.println("Caught StackOverflowError");
+ }
+
+ // Test that a signal in native code works.
+ testSignal2();
+ }
+}
diff --git a/test/Android.libarttest.mk b/test/Android.libarttest.mk
index 2d139a6..1054203 100644
--- a/test/Android.libarttest.mk
+++ b/test/Android.libarttest.mk
@@ -21,6 +21,7 @@
LIBARTTEST_COMMON_SRC_FILES := \
004-JniTest/jni_test.cc \
004-SignalTest/signaltest.cc \
+ 004-SignalTest2/signaltest.cc \
004-ReferenceMap/stack_walk_refmap_jni.cc \
004-StackWalk/stack_walk_jni.cc \
004-UnsafeTest/unsafe_test.cc \
diff --git a/test/Android.run-test.mk b/test/Android.run-test.mk
index e4ee4a7..0b6b27a 100644
--- a/test/Android.run-test.mk
+++ b/test/Android.run-test.mk
@@ -189,6 +189,7 @@
# Tests that are broken with tracing.
TEST_ART_BROKEN_TRACE_RUN_TESTS := \
004-SignalTest \
+ 004-SignalTest2 \
018-stack-overflow \
097-duplicate-method \
107-int-math2