platform_system_core/base/logging.cpp

302 lines
8.7 KiB
C++

/*
* Copyright (C) 2015 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 "base/logging.h"
#include <iostream>
#include <limits>
#include <sstream>
#include <string>
#include <vector>
#include "base/strings.h"
#include "cutils/threads.h"
// Headers for LogMessage::LogLine.
#ifdef __ANDROID__
#include <android/set_abort_message.h>
#include "cutils/log.h"
#else
#include <sys/types.h>
#include <unistd.h>
#endif
namespace android {
namespace base {
static std::mutex logging_lock;
static LogSeverity gMinimumLogSeverity = INFO;
static std::unique_ptr<std::string> gCmdLine;
static std::unique_ptr<std::string> gProgramInvocationName;
static std::unique_ptr<std::string> gProgramInvocationShortName;
const char* GetCmdLine() {
return (gCmdLine.get() != nullptr) ? gCmdLine->c_str() : nullptr;
}
const char* ProgramInvocationName() {
return (gProgramInvocationName.get() != nullptr)
? gProgramInvocationName->c_str()
: "unknown";
}
const char* ProgramInvocationShortName() {
return (gProgramInvocationShortName.get() != nullptr)
? gProgramInvocationShortName->c_str()
: "unknown";
}
void InitLogging(char* argv[]) {
if (gCmdLine.get() != nullptr) {
return;
}
// Stash the command line for later use. We can use /proc/self/cmdline on
// Linux to recover this, but we don't have that luxury on the Mac, and there
// are a couple of argv[0] variants that are commonly used.
if (argv != nullptr) {
gCmdLine.reset(new std::string(argv[0]));
for (size_t i = 1; argv[i] != nullptr; ++i) {
gCmdLine->append(" ");
gCmdLine->append(argv[i]);
}
gProgramInvocationName.reset(new std::string(argv[0]));
const char* last_slash = strrchr(argv[0], '/');
gProgramInvocationShortName.reset(
new std::string((last_slash != nullptr) ? last_slash + 1 : argv[0]));
} else {
// TODO: fall back to /proc/self/cmdline when argv is NULL on Linux.
gCmdLine.reset(new std::string("<unset>"));
}
const char* tags = getenv("ANDROID_LOG_TAGS");
if (tags == nullptr) {
return;
}
std::vector<std::string> specs = Split(tags, " ");
for (size_t i = 0; i < specs.size(); ++i) {
// "tag-pattern:[vdiwefs]"
std::string spec(specs[i]);
if (spec.size() == 3 && StartsWith(spec, "*:")) {
switch (spec[2]) {
case 'v':
gMinimumLogSeverity = VERBOSE;
continue;
case 'd':
gMinimumLogSeverity = DEBUG;
continue;
case 'i':
gMinimumLogSeverity = INFO;
continue;
case 'w':
gMinimumLogSeverity = WARNING;
continue;
case 'e':
gMinimumLogSeverity = ERROR;
continue;
case 'f':
gMinimumLogSeverity = FATAL;
continue;
// liblog will even suppress FATAL if you say 's' for silent, but that's
// crazy!
case 's':
gMinimumLogSeverity = FATAL;
continue;
}
}
LOG(FATAL) << "unsupported '" << spec << "' in ANDROID_LOG_TAGS (" << tags
<< ")";
}
}
// This indirection greatly reduces the stack impact of having lots of
// checks/logging in a function.
class LogMessageData {
public:
LogMessageData(const char* file, unsigned int line, LogSeverity severity,
int error)
: file_(file), line_number_(line), severity_(severity), error_(error) {
const char* last_slash = strrchr(file, '/');
file = (last_slash == nullptr) ? file : last_slash + 1;
}
const char* GetFile() const {
return file_;
}
unsigned int GetLineNumber() const {
return line_number_;
}
LogSeverity GetSeverity() const {
return severity_;
}
int GetError() const {
return error_;
}
std::ostream& GetBuffer() {
return buffer_;
}
std::string ToString() const {
return buffer_.str();
}
private:
std::ostringstream buffer_;
const char* const file_;
const unsigned int line_number_;
const LogSeverity severity_;
const int error_;
DISALLOW_COPY_AND_ASSIGN(LogMessageData);
};
LogMessage::LogMessage(const char* file, unsigned int line,
LogSeverity severity, int error)
: data_(new LogMessageData(file, line, severity, error)) {
}
LogMessage::~LogMessage() {
if (data_->GetSeverity() < gMinimumLogSeverity) {
return; // No need to format something we're not going to output.
}
// Finish constructing the message.
if (data_->GetError() != -1) {
data_->GetBuffer() << ": " << strerror(data_->GetError());
}
std::string msg(data_->ToString());
// Do the actual logging with the lock held.
{
std::lock_guard<std::mutex> lock(logging_lock);
if (msg.find('\n') == std::string::npos) {
LogLine(data_->GetFile(), data_->GetLineNumber(), data_->GetSeverity(),
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(),
&msg[i]);
i = nl + 1;
}
}
}
// Abort if necessary.
if (data_->GetSeverity() == FATAL) {
#ifdef __ANDROID__
android_set_abort_message(msg.c_str());
#endif
abort();
}
}
std::ostream& LogMessage::stream() {
return data_->GetBuffer();
}
#ifdef __ANDROID__
static const android_LogPriority kLogSeverityToAndroidLogPriority[] = {
ANDROID_LOG_VERBOSE, ANDROID_LOG_DEBUG, ANDROID_LOG_INFO,
ANDROID_LOG_WARN, ANDROID_LOG_ERROR, ANDROID_LOG_FATAL};
static_assert(arraysize(kLogSeverityToAndroidLogPriority) == FATAL + 1,
"Mismatch in size of kLogSeverityToAndroidLogPriority and values "
"in LogSeverity");
#endif
void LogMessage::LogLine(const char* file, unsigned int line,
LogSeverity log_severity, const char* message) {
#ifdef __ANDROID__
const char* tag = ProgramInvocationShortName();
int priority = kLogSeverityToAndroidLogPriority[log_severity];
if (priority == ANDROID_LOG_FATAL) {
LOG_PRI(priority, tag, "%s:%u] %s", file, line, message);
} else {
LOG_PRI(priority, tag, "%s", message);
}
#else
static const char* log_characters = "VDIWEF";
CHECK_EQ(strlen(log_characters), FATAL + 1U);
char severity = log_characters[log_severity];
fprintf(stderr, "%s %c %5d %5d %s:%u] %s\n", ProgramInvocationShortName(),
severity, getpid(), gettid(), file, line, message);
#endif
}
void LogMessage::LogLineLowStack(const char* file, unsigned int line,
LogSeverity log_severity, const char* message) {
#ifdef __ANDROID__
// Use android_writeLog() to avoid stack-based buffers used by
// android_printLog().
const char* tag = ProgramInvocationShortName();
int priority = kLogSeverityToAndroidLogPriority[log_severity];
char* buf = nullptr;
size_t buf_size = 0u;
if (priority == ANDROID_LOG_FATAL) {
// Allocate buffer for snprintf(buf, buf_size, "%s:%u] %s", file, line,
// message) below. If allocation fails, fall back to printing only the
// message.
buf_size = strlen(file) + 1 /* ':' */ +
std::numeric_limits<typeof(line)>::max_digits10 + 2 /* "] " */ +
strlen(message) + 1 /* terminating 0 */;
buf = reinterpret_cast<char*>(malloc(buf_size));
}
if (buf != nullptr) {
snprintf(buf, buf_size, "%s:%u] %s", file, line, message);
android_writeLog(priority, tag, buf);
free(buf);
} else {
android_writeLog(priority, tag, message);
}
#else
static const char* log_characters = "VDIWEF";
CHECK_EQ(strlen(log_characters), FATAL + 1U);
const char* program_name = ProgramInvocationShortName();
write(STDERR_FILENO, program_name, strlen(program_name));
write(STDERR_FILENO, " ", 1);
write(STDERR_FILENO, &log_characters[log_severity], 1);
write(STDERR_FILENO, " ", 1);
// TODO: pid and tid.
write(STDERR_FILENO, file, strlen(file));
// TODO: line.
UNUSED(line);
write(STDERR_FILENO, "] ", 2);
write(STDERR_FILENO, message, strlen(message));
write(STDERR_FILENO, "\n", 1);
#endif
}
ScopedLogSeverity::ScopedLogSeverity(LogSeverity level) {
old_ = gMinimumLogSeverity;
gMinimumLogSeverity = level;
}
ScopedLogSeverity::~ScopedLogSeverity() {
gMinimumLogSeverity = old_;
}
} // namespace base
} // namespace android