Reading from logd in WRAP mode is expected to take a long time,
don't abort it after 30s.
Adds a new CTS test to verify the behaviour.
Bug: 64143705
Test: New and existing CTS tests pass. Manual testing with logcat.
(cherry picked from commit 64acdf77d6f89a72be9192b35e0fc34242c23e34)
Change-Id: Ic2ec131a3aee293ee865c46e62566ddd82ec2507
diff --git a/liblog/logd_reader.c b/liblog/logd_reader.c
index 600f4bb..603ba24 100644
--- a/liblog/logd_reader.c
+++ b/liblog/logd_reader.c
@@ -590,20 +590,30 @@
memset(log_msg, 0, sizeof(*log_msg));
+ unsigned int new_alarm = 0;
if (logger_list->mode & ANDROID_LOG_NONBLOCK) {
+ if ((logger_list->mode & ANDROID_LOG_WRAP) &&
+ (logger_list->start.tv_sec || logger_list->start.tv_nsec)) {
+ /* b/64143705 */
+ new_alarm = (ANDROID_LOG_WRAP_DEFAULT_TIMEOUT * 11) / 10 + 10;
+ logger_list->mode &= ~ANDROID_LOG_WRAP;
+ } else {
+ new_alarm = 30;
+ }
+
memset(&ignore, 0, sizeof(ignore));
ignore.sa_handler = caught_signal;
sigemptyset(&ignore.sa_mask);
/* particularily useful if tombstone is reporting for logd */
sigaction(SIGALRM, &ignore, &old_sigaction);
- old_alarm = alarm(30);
+ old_alarm = alarm(new_alarm);
}
/* NOTE: SOCK_SEQPACKET guarantees we read exactly one full entry */
ret = recv(ret, log_msg, LOGGER_ENTRY_MAX_LEN, 0);
e = errno;
- if (logger_list->mode & ANDROID_LOG_NONBLOCK) {
+ if (new_alarm) {
if ((ret == 0) || (e == EINTR)) {
e = EAGAIN;
ret = -1;
diff --git a/liblog/tests/Android.mk b/liblog/tests/Android.mk
index 91044ab..5571ce9 100644
--- a/liblog/tests/Android.mk
+++ b/liblog/tests/Android.mk
@@ -64,7 +64,8 @@
log_radio_test.cpp \
log_read_test.cpp \
log_system_test.cpp \
- log_time_test.cpp
+ log_time_test.cpp \
+ log_wrap_test.cpp
# Build tests for the device (with .so). Run with:
# adb shell /data/nativetest/liblog-unit-tests/liblog-unit-tests
diff --git a/liblog/tests/log_wrap_test.cpp b/liblog/tests/log_wrap_test.cpp
new file mode 100644
index 0000000..ebf0b15
--- /dev/null
+++ b/liblog/tests/log_wrap_test.cpp
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2013-2017 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 <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <string>
+
+#include <android-base/chrono_utils.h>
+#include <android-base/stringprintf.h>
+#include <android/log.h> // minimal logging API
+#include <gtest/gtest.h>
+#include <log/log_properties.h>
+#include <log/log_read.h>
+#include <log/log_time.h>
+#include <log/log_transport.h>
+
+#ifdef __ANDROID__
+static void read_with_wrap() {
+ android_set_log_transport(LOGGER_LOGD);
+
+ // Read the last line in the log to get a starting timestamp. We're assuming
+ // the log is not empty.
+ const int mode = ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK;
+ struct logger_list* logger_list =
+ android_logger_list_open(LOG_ID_MAIN, mode, 1000, 0);
+
+ ASSERT_NE(logger_list, nullptr);
+
+ log_msg log_msg;
+ int ret = android_logger_list_read(logger_list, &log_msg);
+ android_logger_list_close(logger_list);
+ ASSERT_GT(ret, 0);
+
+ log_time start(log_msg.entry.sec, log_msg.entry.nsec);
+ ASSERT_NE(start, log_time());
+
+ logger_list =
+ android_logger_list_alloc_time(mode | ANDROID_LOG_WRAP, start, 0);
+ ASSERT_NE(logger_list, nullptr);
+
+ struct logger* logger = android_logger_open(logger_list, LOG_ID_MAIN);
+ EXPECT_NE(logger, nullptr);
+ if (logger) {
+ android_logger_list_read(logger_list, &log_msg);
+ }
+
+ android_logger_list_close(logger_list);
+}
+
+static void caught_signal(int /* signum */) {
+}
+#endif
+
+// b/64143705 confirm fixed
+TEST(liblog, wrap_mode_blocks) {
+#ifdef __ANDROID__
+
+ android::base::Timer timer;
+
+ // The read call is expected to take up to 2 hours in the happy case.
+ // We only want to make sure it waits for longer than 30s, but we can't
+ // use an alarm as the implementation uses it. So we run the test in
+ // a separate process.
+ pid_t pid = fork();
+
+ if (pid == 0) {
+ // child
+ read_with_wrap();
+ _exit(0);
+ }
+
+ struct sigaction ignore, old_sigaction;
+ memset(&ignore, 0, sizeof(ignore));
+ ignore.sa_handler = caught_signal;
+ sigemptyset(&ignore.sa_mask);
+ sigaction(SIGALRM, &ignore, &old_sigaction);
+ alarm(45);
+
+ bool killed = false;
+ for (;;) {
+ siginfo_t info = {};
+ // This wait will succeed if the child exits, or fail with EINTR if the
+ // alarm goes off first - a loose approximation to a timed wait.
+ int ret = waitid(P_PID, pid, &info, WEXITED);
+ if (ret >= 0 || errno != EINTR) {
+ EXPECT_EQ(ret, 0);
+ if (!killed) {
+ EXPECT_EQ(info.si_status, 0);
+ }
+ break;
+ }
+ unsigned int alarm_left = alarm(0);
+ if (alarm_left > 0) {
+ alarm(alarm_left);
+ } else {
+ kill(pid, SIGTERM);
+ killed = true;
+ }
+ }
+
+ alarm(0);
+ EXPECT_GT(timer.duration(), std::chrono::seconds(40));
+#else
+ GTEST_LOG_(INFO) << "This test does nothing.\n";
+#endif
+}