// Copyright (c) 2006, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: Maxim Lifantsev
//
// logging_unittest.cc covers the functionality herein
#include "utilities.h"
#include <stdarg.h>
#include <stdio.h>
#include <errno.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h> // for close() and write()
#endif
#include <fcntl.h> // for open()
#include <time.h>
#include "config.h"
#include "glog/logging.h" // To pick up flag settings etc.
#include "glog/raw_logging.h"
#include "base/commandlineflags.h"
#ifdef HAVE_STACKTRACE
# include "stacktrace.h"
#endif
#if defined(HAVE_SYSCALL_H)
#include <syscall.h> // for syscall()
#elif defined(HAVE_SYS_SYSCALL_H)
#include <sys/syscall.h> // for syscall()
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#if defined(HAVE_SYSCALL_H) || defined(HAVE_SYS_SYSCALL_H)
# define safe_write(fd, s, len) syscall(SYS_write, fd, s, len)
#else
// Not so safe, but what can you do?
# define safe_write(fd, s, len) write(fd, s, len)
#endif
_START_GOOGLE_NAMESPACE_
// CAVEAT: vsnprintf called from *DoRawLog below has some (exotic) code paths
// that invoke malloc() and getenv() that might acquire some locks.
// If this becomes a problem we should reimplement a subset of vsnprintf
// that does not need locks and malloc.
// Helper for RawLog__ below.
// *DoRawLog writes to *buf of *size and move them past the written portion.
// It returns true iff there was no overflow or error.
static bool DoRawLog(char** buf, int* size, const char* format, ...) {
va_list ap;
va_start(ap, format);
int n = vsnprintf(*buf, *size, format, ap);
va_end(ap);
if (n < 0 || n > *size) return false;
*size -= n;
*buf += n;
return true;
}
// Helper for RawLog__ below.
inline static bool VADoRawLog(char** buf, int* size,
const char* format, va_list ap) {
int n = vsnprintf(*buf, *size, format, ap);
if (n < 0 || n > *size) return false;
*size -= n;
*buf += n;
return true;
}
static const int kLogBufSize = 3000;
static bool crashed = false;
static CrashReason crash_reason;
static char crash_buf[kLogBufSize + 1] = { 0 }; // Will end in '\0'
void RawLog__(LogSeverity severity, const char* file, int line,
const char* format, ...) {
if (!(FLAGS_logtostderr || severity >= FLAGS_stderrthreshold ||
FLAGS_alsologtostderr || !IsGoogleLoggingInitialized())) {
return; // this stderr log message is suppressed
}
// can't call localtime_r here: it can allocate
char buffer[kLogBufSize];
char* buf = buffer;
int size = sizeof(buffer);
// NOTE: this format should match the specification in base/logging.h
DoRawLog(&buf, &size, "%c00000000 00:00:00.000000 %5u %s:%d] RAW: ",
LogSeverityNames[severity][0],
static_cast<unsigned int>(GetTID()),
const_basename(const_cast<char *>(file)), line);
// Record the position and size of the buffer after the prefix
const char* msg_start = buf;
const int msg_size = size;
va_list ap;
va_start(ap, format);
bool no_chop = VADoRawLog(&buf, &size, format, ap);
va_end(ap);
if (no_chop) {
DoRawLog(&buf, &size, "\n");
} else {
DoRawLog(&buf, &size, "RAW_LOG ERROR: The Message was too long!\n");
}
// We make a raw syscall to write directly to the stderr file descriptor,
// avoiding FILE buffering (to avoid invoking malloc()), and bypassing
// libc (to side-step any libc interception).
// We write just once to avoid races with other invocations of RawLog__.
safe_write(STDERR_FILENO, buffer, strlen(buffer));
if (severity == GLOG_FATAL) {
if (!sync_val_compare_and_swap(&crashed, false, true)) {
crash_reason.filename = file;
crash_reason.line_number = line;
memcpy(crash_buf, msg_start, msg_size); // Don't include prefix
crash_reason.message = crash_buf;
#ifdef HAVE_STACKTRACE
crash_reason.depth =
GetStackTrace(crash_reason.stack, ARRAYSIZE(crash_reason.stack), 1);
#else
crash_reason.depth = 0;
#endif
SetCrashReason(&crash_reason);
}
LogMessage::Fail(); // abort()
}
}
_END_GOOGLE_NAMESPACE_
