Merge "base: reimagine line splitting in logger.cpp" into rvc-dev
diff --git a/base/Android.bp b/base/Android.bp
index 0c78719..4556f9b 100644
--- a/base/Android.bp
+++ b/base/Android.bp
@@ -159,6 +159,7 @@
"errors_test.cpp",
"expected_test.cpp",
"file_test.cpp",
+ "logging_splitters_test.cpp",
"logging_test.cpp",
"macros_test.cpp",
"mapped_file_test.cpp",
diff --git a/base/include/android-base/logging.h b/base/include/android-base/logging.h
index accc225..26827fb 100644
--- a/base/include/android-base/logging.h
+++ b/base/include/android-base/logging.h
@@ -118,8 +118,10 @@
void SetDefaultTag(const std::string& tag);
-// We expose this even though it is the default because a user that wants to
-// override the default log buffer will have to construct this themselves.
+// The LogdLogger sends chunks of up to ~4000 bytes at a time to logd. It does not prevent other
+// threads from writing to logd between sending each chunk, so other threads may interleave their
+// messages. If preventing interleaving is required, then a custom logger that takes a lock before
+// calling this logger should be provided.
class LogdLogger {
public:
explicit LogdLogger(LogId default_log_id = android::base::MAIN);
diff --git a/base/logging.cpp b/base/logging.cpp
index 3c73fea..6e9c67f 100644
--- a/base/logging.cpp
+++ b/base/logging.cpp
@@ -61,6 +61,7 @@
#include <android-base/threads.h>
#include "liblog_symbols.h"
+#include "logging_splitters.h"
namespace android {
namespace base {
@@ -190,11 +191,6 @@
}
}
-static std::mutex& LoggingLock() {
- static auto& logging_lock = *new std::mutex();
- return logging_lock;
-}
-
static LogFunction& Logger() {
#ifdef __ANDROID__
static auto& logger = *new LogFunction(LogdLogger());
@@ -239,8 +235,8 @@
static LogSeverity gMinimumLogSeverity = INFO;
#if defined(__linux__)
-void KernelLogger(android::base::LogId, android::base::LogSeverity severity,
- const char* tag, const char*, unsigned int, const char* msg) {
+static void KernelLogLine(const char* msg, int length, android::base::LogSeverity severity,
+ const char* tag) {
// clang-format off
static constexpr int kLogSeverityToKernelLogLevel[] = {
[android::base::VERBOSE] = 7, // KERN_DEBUG (there is no verbose kernel log
@@ -265,7 +261,7 @@
// TODO: should we automatically break up long lines into multiple lines?
// Or we could log but with something like "..." at the end?
char buf[1024];
- size_t size = snprintf(buf, sizeof(buf), "<%d>%s: %s\n", level, tag, msg);
+ size_t size = snprintf(buf, sizeof(buf), "<%d>%s: %.*s\n", level, tag, length, msg);
if (size > sizeof(buf)) {
size = snprintf(buf, sizeof(buf), "<%d>%s: %zu-byte message too long for printk\n",
level, tag, size);
@@ -276,6 +272,11 @@
iov[0].iov_len = size;
TEMP_FAILURE_RETRY(writev(klog_fd, iov, 1));
}
+
+void KernelLogger(android::base::LogId, android::base::LogSeverity severity, const char* tag,
+ const char*, unsigned int, const char* full_message) {
+ SplitByLines(full_message, KernelLogLine, severity, tag);
+}
#endif
void StderrLogger(LogId, LogSeverity severity, const char* tag, const char* file, unsigned int line,
@@ -288,21 +289,10 @@
#else
localtime_r(&t, &now);
#endif
+ auto output_string =
+ StderrOutputGenerator(now, getpid(), GetThreadId(), severity, tag, file, line, message);
- char timestamp[32];
- strftime(timestamp, sizeof(timestamp), "%m-%d %H:%M:%S", &now);
-
- static const char log_characters[] = "VDIWEFF";
- static_assert(arraysize(log_characters) - 1 == FATAL + 1,
- "Mismatch in size of log_characters and values in LogSeverity");
- char severity_char = log_characters[severity];
- if (file != nullptr) {
- fprintf(stderr, "%s %c %s %5d %5" PRIu64 " %s:%u] %s\n", tag ? tag : "nullptr", severity_char,
- timestamp, getpid(), GetThreadId(), file, line, message);
- } else {
- fprintf(stderr, "%s %c %s %5d %5" PRIu64 " %s\n", tag ? tag : "nullptr", severity_char,
- timestamp, getpid(), GetThreadId(), message);
- }
+ fputs(output_string.c_str(), stderr);
}
void StdioLogger(LogId, LogSeverity severity, const char* /*tag*/, const char* /*file*/,
@@ -324,26 +314,9 @@
abort();
}
-
-LogdLogger::LogdLogger(LogId default_log_id) : default_log_id_(default_log_id) {
-}
-
-void LogdLogger::operator()(LogId id, LogSeverity severity, const char* tag,
- const char* file, unsigned int line,
- const char* message) {
- int32_t priority = LogSeverityToPriority(severity);
- if (id == DEFAULT) {
- id = default_log_id_;
- }
-
+static void LogdLogChunk(LogId id, LogSeverity severity, const char* tag, const char* message) {
int32_t lg_id = LogIdTolog_id_t(id);
-
- char log_message_with_file[4068]; // LOGGER_ENTRY_MAX_PAYLOAD, not available in the NDK.
- if (priority == ANDROID_LOG_FATAL && file != nullptr) {
- snprintf(log_message_with_file, sizeof(log_message_with_file), "%s:%u] %s", file, line,
- message);
- message = log_message_with_file;
- }
+ int32_t priority = LogSeverityToPriority(severity);
static auto& liblog_functions = GetLibLogFunctions();
if (liblog_functions) {
@@ -355,6 +328,17 @@
}
}
+LogdLogger::LogdLogger(LogId default_log_id) : default_log_id_(default_log_id) {}
+
+void LogdLogger::operator()(LogId id, LogSeverity severity, const char* tag, const char* file,
+ unsigned int line, const char* message) {
+ if (id == DEFAULT) {
+ id = default_log_id_;
+ }
+
+ SplitByLogdChunks(id, severity, tag, file, line, message, LogdLogChunk);
+}
+
void InitLogging(char* argv[], LogFunction&& logger, AbortFunction&& aborter) {
SetLogger(std::forward<LogFunction>(logger));
SetAborter(std::forward<AbortFunction>(aborter));
@@ -515,26 +499,8 @@
#endif
}
- {
- // Do the actual logging with the lock held.
- std::lock_guard<std::mutex> lock(LoggingLock());
- if (msg.find('\n') == std::string::npos) {
- LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(), data_->GetTag(),
- msg.c_str());
- } else {
- msg += '\n';
- size_t i = 0;
- while (i < msg.size()) {
- size_t nl = msg.find('\n', i);
- msg[nl] = '\0';
- LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(), data_->GetTag(),
- &msg[i]);
- // Undo the zero-termination so we can give the complete message to the aborter.
- msg[nl] = '\n';
- i = nl + 1;
- }
- }
- }
+ LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(), data_->GetTag(),
+ msg.c_str());
// Abort if necessary.
if (data_->GetSeverity() == FATAL) {
diff --git a/base/logging_splitters.h b/base/logging_splitters.h
new file mode 100644
index 0000000..2ec2b20
--- /dev/null
+++ b/base/logging_splitters.h
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#pragma once
+
+#include <inttypes.h>
+
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+
+#define LOGGER_ENTRY_MAX_PAYLOAD 4068 // This constant is not in the NDK.
+
+namespace android {
+namespace base {
+
+// This splits the message up line by line, by calling log_function with a pointer to the start of
+// each line and the size up to the newline character. It sends size = -1 for the final line.
+template <typename F, typename... Args>
+static void SplitByLines(const char* msg, const F& log_function, Args&&... args) {
+ const char* newline = strchr(msg, '\n');
+ while (newline != nullptr) {
+ log_function(msg, newline - msg, args...);
+ msg = newline + 1;
+ newline = strchr(msg, '\n');
+ }
+
+ log_function(msg, -1, args...);
+}
+
+// This splits the message up into chunks that logs can process delimited by new lines. It calls
+// log_function with the exact null terminated message that should be sent to logd.
+// Note, despite the loops and snprintf's, if severity is not fatal and there are no new lines,
+// this function simply calls log_function with msg without any extra overhead.
+template <typename F>
+static void SplitByLogdChunks(LogId log_id, LogSeverity severity, const char* tag, const char* file,
+ unsigned int line, const char* msg, const F& log_function) {
+ // The maximum size of a payload, after the log header that logd will accept is
+ // LOGGER_ENTRY_MAX_PAYLOAD, so subtract the other elements in the payload to find the size of
+ // the string that we can log in each pass.
+ // The protocol is documented in liblog/README.protocol.md.
+ // Specifically we subtract a byte for the priority, the length of the tag + its null terminator,
+ // and an additional byte for the null terminator on the payload. We subtract an additional 32
+ // bytes for slack, similar to java/android/util/Log.java.
+ ptrdiff_t max_size = LOGGER_ENTRY_MAX_PAYLOAD - strlen(tag) - 35;
+ if (max_size <= 0) {
+ abort();
+ }
+ // If we're logging a fatal message, we'll append the file and line numbers.
+ bool add_file = file != nullptr && (severity == FATAL || severity == FATAL_WITHOUT_ABORT);
+
+ std::string file_header;
+ if (add_file) {
+ file_header = StringPrintf("%s:%u] ", file, line);
+ }
+ int file_header_size = file_header.size();
+
+ __attribute__((uninitialized)) char logd_chunk[max_size + 1];
+ ptrdiff_t chunk_position = 0;
+
+ auto call_log_function = [&]() {
+ log_function(log_id, severity, tag, logd_chunk);
+ chunk_position = 0;
+ };
+
+ auto write_to_logd_chunk = [&](const char* message, int length) {
+ int size_written = 0;
+ const char* new_line = chunk_position > 0 ? "\n" : "";
+ if (add_file) {
+ size_written = snprintf(logd_chunk + chunk_position, sizeof(logd_chunk) - chunk_position,
+ "%s%s%.*s", new_line, file_header.c_str(), length, message);
+ } else {
+ size_written = snprintf(logd_chunk + chunk_position, sizeof(logd_chunk) - chunk_position,
+ "%s%.*s", new_line, length, message);
+ }
+
+ // This should never fail, if it does and we set size_written to 0, which will skip this line
+ // and move to the next one.
+ if (size_written < 0) {
+ size_written = 0;
+ }
+ chunk_position += size_written;
+ };
+
+ const char* newline = strchr(msg, '\n');
+ while (newline != nullptr) {
+ // If we have data in the buffer and this next line doesn't fit, write the buffer.
+ if (chunk_position != 0 && chunk_position + (newline - msg) + 1 + file_header_size > max_size) {
+ call_log_function();
+ }
+
+ // Otherwise, either the next line fits or we have any empty buffer and too large of a line to
+ // ever fit, in both cases, we add it to the buffer and continue.
+ write_to_logd_chunk(msg, newline - msg);
+
+ msg = newline + 1;
+ newline = strchr(msg, '\n');
+ }
+
+ // If we have left over data in the buffer and we can fit the rest of msg, add it to the buffer
+ // then write the buffer.
+ if (chunk_position != 0 &&
+ chunk_position + static_cast<int>(strlen(msg)) + 1 + file_header_size <= max_size) {
+ write_to_logd_chunk(msg, -1);
+ call_log_function();
+ } else {
+ // If the buffer is not empty and we can't fit the rest of msg into it, write its contents.
+ if (chunk_position != 0) {
+ call_log_function();
+ }
+ // Then write the rest of the msg.
+ if (add_file) {
+ snprintf(logd_chunk, sizeof(logd_chunk), "%s%s", file_header.c_str(), msg);
+ log_function(log_id, severity, tag, logd_chunk);
+ } else {
+ log_function(log_id, severity, tag, msg);
+ }
+ }
+}
+
+static std::pair<int, int> CountSizeAndNewLines(const char* message) {
+ int size = 0;
+ int new_lines = 0;
+ while (*message != '\0') {
+ size++;
+ if (*message == '\n') {
+ ++new_lines;
+ }
+ ++message;
+ }
+ return {size, new_lines};
+}
+
+// This adds the log header to each line of message and returns it as a string intended to be
+// written to stderr.
+static std::string StderrOutputGenerator(const struct tm& now, int pid, uint64_t tid,
+ LogSeverity severity, const char* tag, const char* file,
+ unsigned int line, const char* message) {
+ char timestamp[32];
+ strftime(timestamp, sizeof(timestamp), "%m-%d %H:%M:%S", &now);
+
+ static const char log_characters[] = "VDIWEFF";
+ static_assert(arraysize(log_characters) - 1 == FATAL + 1,
+ "Mismatch in size of log_characters and values in LogSeverity");
+ char severity_char = log_characters[severity];
+ std::string line_prefix;
+ if (file != nullptr) {
+ line_prefix = StringPrintf("%s %c %s %5d %5" PRIu64 " %s:%u] ", tag ? tag : "nullptr",
+ severity_char, timestamp, pid, tid, file, line);
+ } else {
+ line_prefix = StringPrintf("%s %c %s %5d %5" PRIu64 " ", tag ? tag : "nullptr", severity_char,
+ timestamp, pid, tid);
+ }
+
+ auto [size, new_lines] = CountSizeAndNewLines(message);
+ std::string output_string;
+ output_string.reserve(size + new_lines * line_prefix.size() + 1);
+
+ auto concat_lines = [&](const char* message, int size) {
+ output_string.append(line_prefix);
+ if (size == -1) {
+ output_string.append(message);
+ } else {
+ output_string.append(message, size);
+ }
+ output_string.append("\n");
+ };
+ SplitByLines(message, concat_lines);
+ return output_string;
+}
+
+} // namespace base
+} // namespace android
diff --git a/base/logging_splitters_test.cpp b/base/logging_splitters_test.cpp
new file mode 100644
index 0000000..679d19e
--- /dev/null
+++ b/base/logging_splitters_test.cpp
@@ -0,0 +1,325 @@
+/*
+ * Copyright (C) 2020 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 "logging_splitters.h"
+
+#include <string>
+#include <vector>
+
+#include <android-base/strings.h>
+#include <gtest/gtest.h>
+
+namespace android {
+namespace base {
+
+void TestNewlineSplitter(const std::string& input,
+ const std::vector<std::string>& expected_output) {
+ std::vector<std::string> output;
+ auto logger_function = [&](const char* msg, int length) {
+ if (length == -1) {
+ output.push_back(msg);
+ } else {
+ output.push_back(std::string(msg, length));
+ }
+ };
+ SplitByLines(input.c_str(), logger_function);
+
+ EXPECT_EQ(expected_output, output);
+}
+
+TEST(logging_splitters, NewlineSplitter_EmptyString) {
+ TestNewlineSplitter("", std::vector<std::string>{""});
+}
+
+TEST(logging_splitters, NewlineSplitter_BasicString) {
+ TestNewlineSplitter("normal string", std::vector<std::string>{"normal string"});
+}
+
+TEST(logging_splitters, NewlineSplitter_ormalBasicStringTrailingNewline) {
+ TestNewlineSplitter("normal string\n", std::vector<std::string>{"normal string", ""});
+}
+
+TEST(logging_splitters, NewlineSplitter_MultilineTrailing) {
+ TestNewlineSplitter("normal string\nsecond string\nthirdstring",
+ std::vector<std::string>{"normal string", "second string", "thirdstring"});
+}
+
+TEST(logging_splitters, NewlineSplitter_MultilineTrailingNewline) {
+ TestNewlineSplitter(
+ "normal string\nsecond string\nthirdstring\n",
+ std::vector<std::string>{"normal string", "second string", "thirdstring", ""});
+}
+
+TEST(logging_splitters, NewlineSplitter_MultilineEmbeddedNewlines) {
+ TestNewlineSplitter(
+ "normal string\n\n\nsecond string\n\nthirdstring\n",
+ std::vector<std::string>{"normal string", "", "", "second string", "", "thirdstring", ""});
+}
+
+void TestLogdChunkSplitter(const std::string& tag, const std::string& file,
+ const std::string& input,
+ const std::vector<std::string>& expected_output) {
+ std::vector<std::string> output;
+ auto logger_function = [&](LogId, LogSeverity, const char*, const char* msg) {
+ output.push_back(msg);
+ };
+
+ SplitByLogdChunks(MAIN, FATAL, tag.c_str(), file.empty() ? nullptr : file.c_str(), 1000,
+ input.c_str(), logger_function);
+
+ auto return_lengths = [&] {
+ std::string sizes;
+ sizes += "expected_output sizes:";
+ for (const auto& string : expected_output) {
+ sizes += " " + std::to_string(string.size());
+ }
+ sizes += "\noutput sizes:";
+ for (const auto& string : output) {
+ sizes += " " + std::to_string(string.size());
+ }
+ return sizes;
+ };
+
+ EXPECT_EQ(expected_output, output) << return_lengths();
+}
+
+TEST(logging_splitters, LogdChunkSplitter_EmptyString) {
+ TestLogdChunkSplitter("tag", "", "", std::vector<std::string>{""});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_BasicString) {
+ TestLogdChunkSplitter("tag", "", "normal string", std::vector<std::string>{"normal string"});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_NormalBasicStringTrailingNewline) {
+ TestLogdChunkSplitter("tag", "", "normal string\n", std::vector<std::string>{"normal string\n"});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_MultilineTrailing) {
+ TestLogdChunkSplitter("tag", "", "normal string\nsecond string\nthirdstring",
+ std::vector<std::string>{"normal string\nsecond string\nthirdstring"});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_MultilineTrailingNewline) {
+ TestLogdChunkSplitter("tag", "", "normal string\nsecond string\nthirdstring\n",
+ std::vector<std::string>{"normal string\nsecond string\nthirdstring\n"});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_MultilineEmbeddedNewlines) {
+ TestLogdChunkSplitter(
+ "tag", "", "normal string\n\n\nsecond string\n\nthirdstring\n",
+ std::vector<std::string>{"normal string\n\n\nsecond string\n\nthirdstring\n"});
+}
+
+// This test should return the same string, the logd logger itself will truncate down to size.
+// This has historically been the behavior both in libbase and liblog.
+TEST(logging_splitters, LogdChunkSplitter_HugeLineNoNewline) {
+ auto long_string = std::string(LOGGER_ENTRY_MAX_PAYLOAD, 'x');
+ ASSERT_EQ(LOGGER_ENTRY_MAX_PAYLOAD, static_cast<int>(long_string.size()));
+
+ TestLogdChunkSplitter("tag", "", long_string, std::vector{long_string});
+}
+
+std::string ReduceToMaxSize(const std::string& tag, const std::string& string) {
+ return string.substr(0, LOGGER_ENTRY_MAX_PAYLOAD - tag.size() - 35);
+}
+
+TEST(logging_splitters, LogdChunkSplitter_MultipleHugeLineNoNewline) {
+ auto long_string_x = std::string(LOGGER_ENTRY_MAX_PAYLOAD, 'x');
+ auto long_string_y = std::string(LOGGER_ENTRY_MAX_PAYLOAD, 'y');
+ auto long_string_z = std::string(LOGGER_ENTRY_MAX_PAYLOAD, 'z');
+
+ auto long_strings = long_string_x + '\n' + long_string_y + '\n' + long_string_z;
+
+ std::string tag = "tag";
+ std::vector expected = {ReduceToMaxSize(tag, long_string_x), ReduceToMaxSize(tag, long_string_y),
+ long_string_z};
+
+ TestLogdChunkSplitter(tag, "", long_strings, expected);
+}
+
+// With a ~4k buffer, we should print 2 long strings per logger call.
+TEST(logging_splitters, LogdChunkSplitter_Multiple2kLines) {
+ std::vector expected = {
+ std::string(2000, 'a') + '\n' + std::string(2000, 'b'),
+ std::string(2000, 'c') + '\n' + std::string(2000, 'd'),
+ std::string(2000, 'e') + '\n' + std::string(2000, 'f'),
+ };
+
+ auto long_strings = Join(expected, '\n');
+
+ TestLogdChunkSplitter("tag", "", long_strings, expected);
+}
+
+TEST(logging_splitters, LogdChunkSplitter_ExactSizedLines) {
+ const char* tag = "tag";
+ ptrdiff_t max_size = LOGGER_ENTRY_MAX_PAYLOAD - strlen(tag) - 35;
+ auto long_string_a = std::string(max_size, 'a');
+ auto long_string_b = std::string(max_size, 'b');
+ auto long_string_c = std::string(max_size, 'c');
+
+ auto long_strings = long_string_a + '\n' + long_string_b + '\n' + long_string_c;
+
+ TestLogdChunkSplitter(tag, "", long_strings,
+ std::vector{long_string_a, long_string_b, long_string_c});
+}
+
+TEST(logging_splitters, LogdChunkSplitter_UnderEqualOver) {
+ std::string tag = "tag";
+ ptrdiff_t max_size = LOGGER_ENTRY_MAX_PAYLOAD - tag.size() - 35;
+
+ auto first_string_size = 1000;
+ auto first_string = std::string(first_string_size, 'a');
+ auto second_string_size = max_size - first_string_size - 1;
+ auto second_string = std::string(second_string_size, 'b');
+
+ auto exact_string = std::string(max_size, 'c');
+
+ auto large_string = std::string(max_size + 50, 'd');
+
+ auto final_string = std::string("final string!\n\nfinal \n \n final \n");
+
+ std::vector expected = {first_string + '\n' + second_string, exact_string,
+ ReduceToMaxSize(tag, large_string), final_string};
+
+ std::vector input_strings = {first_string + '\n' + second_string, exact_string, large_string,
+ final_string};
+ auto long_strings = Join(input_strings, '\n');
+
+ TestLogdChunkSplitter(tag, "", long_strings, expected);
+}
+
+TEST(logging_splitters, LogdChunkSplitter_WithFile) {
+ std::string tag = "tag";
+ std::string file = "/path/to/myfile.cpp";
+ int line = 1000;
+ auto file_header = StringPrintf("%s:%d] ", file.c_str(), line);
+ ptrdiff_t max_size = LOGGER_ENTRY_MAX_PAYLOAD - tag.size() - 35;
+
+ auto first_string_size = 1000;
+ auto first_string = std::string(first_string_size, 'a');
+ auto second_string_size = max_size - first_string_size - 1 - 2 * file_header.size();
+ auto second_string = std::string(second_string_size, 'b');
+
+ auto exact_string = std::string(max_size - file_header.size(), 'c');
+
+ auto large_string = std::string(max_size + 50, 'd');
+
+ auto final_string = std::string("final string!");
+
+ std::vector expected = {
+ file_header + first_string + '\n' + file_header + second_string, file_header + exact_string,
+ file_header + ReduceToMaxSize(file_header + tag, large_string), file_header + final_string};
+
+ std::vector input_strings = {first_string + '\n' + second_string, exact_string, large_string,
+ final_string};
+ auto long_strings = Join(input_strings, '\n');
+
+ TestLogdChunkSplitter(tag, file, long_strings, expected);
+}
+
+// We set max_size based off of tag, so if it's too large, the buffer will be sized wrong.
+// We could recover from this, but it's certainly an error for someone to attempt to use a tag this
+// large, so we abort instead.
+TEST(logging_splitters, LogdChunkSplitter_TooLongTag) {
+ auto long_tag = std::string(5000, 'x');
+ auto logger_function = [](LogId, LogSeverity, const char*, const char*) {};
+ ASSERT_DEATH(
+ SplitByLogdChunks(MAIN, ERROR, long_tag.c_str(), nullptr, 0, "message", logger_function), "");
+}
+
+// We do handle excessively large file names correctly however.
+TEST(logging_splitters, LogdChunkSplitter_TooLongFile) {
+ auto long_file = std::string(5000, 'x');
+ std::string tag = "tag";
+
+ std::vector expected = {ReduceToMaxSize(tag, long_file), ReduceToMaxSize(tag, long_file)};
+
+ TestLogdChunkSplitter(tag, long_file, "can't see me\nor me", expected);
+}
+
+void TestStderrOutputGenerator(const char* tag, const char* file, int line, const char* message,
+ const std::string& expected) {
+ // All log messages will show "01-01 00:00:00"
+ struct tm now = {
+ .tm_sec = 0,
+ .tm_min = 0,
+ .tm_hour = 0,
+ .tm_mday = 1,
+ .tm_mon = 0,
+ .tm_year = 1970,
+ };
+
+ int pid = 1234; // All log messages will have 1234 for their PID.
+ uint64_t tid = 4321; // All log messages will have 4321 for their TID.
+
+ auto result = StderrOutputGenerator(now, pid, tid, ERROR, tag, file, line, message);
+ EXPECT_EQ(expected, result);
+}
+
+TEST(logging_splitters, StderrOutputGenerator_Basic) {
+ TestStderrOutputGenerator(nullptr, nullptr, 0, "simple message",
+ "nullptr E 01-01 00:00:00 1234 4321 simple message\n");
+ TestStderrOutputGenerator("tag", nullptr, 0, "simple message",
+ "tag E 01-01 00:00:00 1234 4321 simple message\n");
+ TestStderrOutputGenerator(
+ "tag", "/path/to/some/file", 0, "simple message",
+ "tag E 01-01 00:00:00 1234 4321 /path/to/some/file:0] simple message\n");
+}
+
+TEST(logging_splitters, StderrOutputGenerator_NewlineTagAndFile) {
+ TestStderrOutputGenerator("tag\n\n", nullptr, 0, "simple message",
+ "tag\n\n E 01-01 00:00:00 1234 4321 simple message\n");
+ TestStderrOutputGenerator(
+ "tag", "/path/to/some/file\n\n", 0, "simple message",
+ "tag E 01-01 00:00:00 1234 4321 /path/to/some/file\n\n:0] simple message\n");
+}
+
+TEST(logging_splitters, StderrOutputGenerator_TrailingNewLine) {
+ TestStderrOutputGenerator(
+ "tag", nullptr, 0, "simple message\n",
+ "tag E 01-01 00:00:00 1234 4321 simple message\ntag E 01-01 00:00:00 1234 4321 \n");
+}
+
+TEST(logging_splitters, StderrOutputGenerator_MultiLine) {
+ const char* expected_result =
+ "tag E 01-01 00:00:00 1234 4321 simple message\n"
+ "tag E 01-01 00:00:00 1234 4321 \n"
+ "tag E 01-01 00:00:00 1234 4321 \n"
+ "tag E 01-01 00:00:00 1234 4321 another message \n"
+ "tag E 01-01 00:00:00 1234 4321 \n"
+ "tag E 01-01 00:00:00 1234 4321 final message \n"
+ "tag E 01-01 00:00:00 1234 4321 \n"
+ "tag E 01-01 00:00:00 1234 4321 \n"
+ "tag E 01-01 00:00:00 1234 4321 \n";
+
+ TestStderrOutputGenerator("tag", nullptr, 0,
+ "simple message\n\n\nanother message \n\n final message \n\n\n",
+ expected_result);
+}
+
+TEST(logging_splitters, StderrOutputGenerator_MultiLineLong) {
+ auto long_string_a = std::string(4000, 'a');
+ auto long_string_b = std::string(4000, 'b');
+
+ auto message = long_string_a + '\n' + long_string_b;
+ auto expected_result = "tag E 01-01 00:00:00 1234 4321 " + long_string_a + '\n' +
+ "tag E 01-01 00:00:00 1234 4321 " + long_string_b + '\n';
+ TestStderrOutputGenerator("tag", nullptr, 0, message.c_str(), expected_result);
+}
+
+} // namespace base
+} // namespace android
diff --git a/base/logging_test.cpp b/base/logging_test.cpp
index 3a453e6..593e2c1 100644
--- a/base/logging_test.cpp
+++ b/base/logging_test.cpp
@@ -24,8 +24,10 @@
#include <regex>
#include <string>
+#include <thread>
#include "android-base/file.h"
+#include "android-base/scopeguard.h"
#include "android-base/stringprintf.h"
#include "android-base/test_utils.h"
@@ -596,7 +598,7 @@
CapturedStderr cap;
LOG(FATAL) << "foo\nbar";
- EXPECT_EQ(CountLineAborter::newline_count, 1U + 1U); // +1 for final '\n'.
+ EXPECT_EQ(CountLineAborter::newline_count, 1U);
}
__attribute__((constructor)) void TestLoggingInConstructor() {
@@ -617,3 +619,55 @@
// Whereas ERROR logging includes the program name.
ASSERT_EQ(android::base::Basename(android::base::GetExecutablePath()) + ": err\n", cap_err.str());
}
+
+TEST(logging, ForkSafe) {
+#if !defined(_WIN32)
+ using namespace android::base;
+ SetLogger(
+ [&](LogId, LogSeverity, const char*, const char*, unsigned int, const char*) { sleep(3); });
+
+ auto guard = make_scope_guard([&] {
+#ifdef __ANDROID__
+ SetLogger(LogdLogger());
+#else
+ SetLogger(StderrLogger);
+#endif
+ });
+
+ auto thread = std::thread([] {
+ LOG(ERROR) << "This should sleep for 3 seconds, long enough to fork another process, if there "
+ "is no intervention";
+ });
+ thread.detach();
+
+ auto pid = fork();
+ ASSERT_NE(-1, pid);
+
+ if (pid == 0) {
+ // Reset the logger, so the next message doesn't sleep().
+ SetLogger([](LogId, LogSeverity, const char*, const char*, unsigned int, const char*) {});
+ LOG(ERROR) << "This should succeed in the child, only if libbase is forksafe.";
+ _exit(EXIT_SUCCESS);
+ }
+
+ // Wait for up to 3 seconds for the child to exit.
+ int tries = 3;
+ bool found_child = false;
+ while (tries-- > 0) {
+ auto result = waitpid(pid, nullptr, WNOHANG);
+ EXPECT_NE(-1, result);
+ if (result == pid) {
+ found_child = true;
+ break;
+ }
+ sleep(1);
+ }
+
+ EXPECT_TRUE(found_child);
+
+ // Kill the child if it did not exit.
+ if (!found_child) {
+ kill(pid, SIGKILL);
+ }
+#endif
+}