about summary refs log tree commit diff
path: root/src/raw_logging.cc
diff options
context:
space:
mode:
Diffstat (limited to 'src/raw_logging.cc')
-rw-r--r--src/raw_logging.cc158
1 files changed, 158 insertions, 0 deletions
diff --git a/src/raw_logging.cc b/src/raw_logging.cc
new file mode 100644
index 000000000000..ba65961e9053
--- /dev/null
+++ b/src/raw_logging.cc
@@ -0,0 +1,158 @@
+// 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_