Files
ortools-clone/ortools/base/raw_logging.cc
2022-09-09 16:42:22 +02:00

129 lines
4.4 KiB
C++

// Copyright 2010-2022 Google LLC
// 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 "ortools/base/raw_logging.h"
#include <errno.h>
#include <fcntl.h> // for open()
#include <stdarg.h>
#include <stdio.h>
#include <time.h>
#include "absl/base/macros.h"
#include "absl/debugging/stacktrace.h"
#include "ortools/base/flags.h"
#include "ortools/base/log.h"
#include "ortools/base/log_severity.h"
#include "ortools/base/logging_utilities.h"
#if !defined(_MSC_VER)
#include <sys/syscall.h> // for syscall()
#define safe_write(fd, s, len) syscall(SYS_write, fd, s, len)
#else
#include <io.h> // _write()
// Not so safe, but what can you do?
#define safe_write(fd, s, len) _write(fd, s, len)
#endif
#if defined(_MSC_VER) && !defined(__MINGW32__)
enum { STDIN_FILENO = 0, STDOUT_FILENO = 1, STDERR_FILENO = 2 };
#endif
namespace google {
// 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 logging_internal::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 (!(absl::GetFlag(FLAGS_logtostderr) ||
severity >= absl::GetFlag(FLAGS_stderrthreshold) ||
absl::GetFlag(FLAGS_alsologtostderr) ||
!logging_internal::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, "%c0000 00:00:00.000000 %5u %s:%d] RAW: ",
LogSeverityNames[severity][0], logging_internal::GetTID(),
logging_internal::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 (!logging_internal::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;
crash_reason.depth = absl::GetStackTrace(
crash_reason.stack, ABSL_ARRAYSIZE(crash_reason.stack), 1);
SetCrashReason(&crash_reason);
}
LogMessage::Fail(); // abort()
}
}
} // namespace google