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Diffstat (limited to 'trunk/src/base/logging.h')
| -rw-r--r-- | trunk/src/base/logging.h | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/trunk/src/base/logging.h b/trunk/src/base/logging.h new file mode 100644 index 0000000..6aa5c3f --- /dev/null +++ b/trunk/src/base/logging.h @@ -0,0 +1,245 @@ +// Copyright (c) 2005, 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. + +// --- +// This file contains #include information about logging-related stuff. +// Pretty much everybody needs to #include this file so that they can +// log various happenings. +// +#ifndef _LOGGING_H_ +#define _LOGGING_H_ + +#include <config.h> +#include <stdarg.h> +#include <stdlib.h> +#include <stdio.h> +#ifdef HAVE_UNISTD_H +#include <unistd.h> // for write() +#endif +#include <string.h> // for strlen(), strcmp() +#include <assert.h> +#include <errno.h> // for errno +#include "base/commandlineflags.h" + +// On some systems (like freebsd), we can't call write() at all in a +// global constructor, perhaps because errno hasn't been set up. +// Calling the write syscall is safer (it doesn't set errno), so we +// prefer that. Note we don't care about errno for logging: we just +// do logging on a best-effort basis. +#ifdef HAVE_SYS_SYSCALL_H +#include <sys/syscall.h> +#define WRITE_TO_STDERR(buf, len) syscall(SYS_write, STDERR_FILENO, buf, len) +#else +#define WRITE_TO_STDERR(buf, len) write(STDERR_FILENO, buf, len) +#endif + + +// We log all messages at this log-level and below. +// INFO == -1, WARNING == -2, ERROR == -3, FATAL == -4 +DECLARE_int32(verbose); + +// CHECK dies with a fatal error if condition is not true. It is *not* +// controlled by NDEBUG, so the check will be executed regardless of +// compilation mode. Therefore, it is safe to do things like: +// CHECK(fp->Write(x) == 4) +// Note we use write instead of printf/puts to avoid the risk we'll +// call malloc(). +#define CHECK(condition) \ + do { \ + if (!(condition)) { \ + WRITE_TO_STDERR("Check failed: " #condition "\n", \ + sizeof("Check failed: " #condition "\n")-1); \ + exit(1); \ + } \ + } while (0) + +// This takes a message to print. The name is historical. +#define RAW_CHECK(condition, message) \ + do { \ + if (!(condition)) { \ + WRITE_TO_STDERR("Check failed: " #condition ": " message "\n", \ + sizeof("Check failed: " #condition ": " message "\n")-1);\ + exit(1); \ + } \ + } while (0) + +// This is like RAW_CHECK, but only in debug-mode +#ifdef NDEBUG +enum { DEBUG_MODE = 0 }; +#define RAW_DCHECK(condition, message) +#else +enum { DEBUG_MODE = 1 }; +#define RAW_DCHECK(condition, message) RAW_CHECK(condition, message) +#endif + +// This prints errno as well. Note we use write instead of printf/puts to +// avoid the risk we'll call malloc(). +#define PCHECK(condition) \ + do { \ + if (!(condition)) { \ + const int err_no = errno; \ + WRITE_TO_STDERR("Check failed: " #condition ": ", \ + sizeof("Check failed: " #condition ": ")-1); \ + WRITE_TO_STDERR(strerror(err_no), strlen(strerror(err_no))); \ + WRITE_TO_STDERR("\n", sizeof("\n")-1); \ + exit(1); \ + } \ + } while (0) + +// Helper macro for binary operators; prints the two values on error +// Don't use this macro directly in your code, use CHECK_EQ et al below + +// WARNING: These don't compile correctly if one of the arguments is a pointer +// and the other is NULL. To work around this, simply static_cast NULL to the +// type of the desired pointer. + +// TODO(jandrews): Also print the values in case of failure. Requires some +// sort of type-sensitive ToString() function. +#define CHECK_OP(op, val1, val2) \ + do { \ + if (!((val1) op (val2))) { \ + fprintf(stderr, "Check failed: %s %s %s\n", #val1, #op, #val2); \ + exit(1); \ + } \ + } while (0) + +#define CHECK_EQ(val1, val2) CHECK_OP(==, val1, val2) +#define CHECK_NE(val1, val2) CHECK_OP(!=, val1, val2) +#define CHECK_LE(val1, val2) CHECK_OP(<=, val1, val2) +#define CHECK_LT(val1, val2) CHECK_OP(< , val1, val2) +#define CHECK_GE(val1, val2) CHECK_OP(>=, val1, val2) +#define CHECK_GT(val1, val2) CHECK_OP(> , val1, val2) + +// Synonyms for CHECK_* that are used in some unittests. +#define EXPECT_EQ(val1, val2) CHECK_EQ(val1, val2) +#define EXPECT_NE(val1, val2) CHECK_NE(val1, val2) +#define EXPECT_LE(val1, val2) CHECK_LE(val1, val2) +#define EXPECT_LT(val1, val2) CHECK_LT(val1, val2) +#define EXPECT_GE(val1, val2) CHECK_GE(val1, val2) +#define EXPECT_GT(val1, val2) CHECK_GT(val1, val2) +#define ASSERT_EQ(val1, val2) EXPECT_EQ(val1, val2) +#define ASSERT_NE(val1, val2) EXPECT_NE(val1, val2) +#define ASSERT_LE(val1, val2) EXPECT_LE(val1, val2) +#define ASSERT_LT(val1, val2) EXPECT_LT(val1, val2) +#define ASSERT_GE(val1, val2) EXPECT_GE(val1, val2) +#define ASSERT_GT(val1, val2) EXPECT_GT(val1, val2) +// As are these variants. +#define EXPECT_TRUE(cond) CHECK(cond) +#define EXPECT_FALSE(cond) CHECK(!(cond)) +#define EXPECT_STREQ(a, b) CHECK(strcmp(a, b) == 0) +#define ASSERT_TRUE(cond) EXPECT_TRUE(cond) +#define ASSERT_FALSE(cond) EXPECT_FALSE(cond) +#define ASSERT_STREQ(a, b) EXPECT_STREQ(a, b) + +// Used for (libc) functions that return -1 and set errno +#define CHECK_ERR(invocation) PCHECK((invocation) != -1) + +// A few more checks that only happen in debug mode +#ifdef NDEBUG +#define DCHECK_EQ(val1, val2) +#define DCHECK_NE(val1, val2) +#define DCHECK_LE(val1, val2) +#define DCHECK_LT(val1, val2) +#define DCHECK_GE(val1, val2) +#define DCHECK_GT(val1, val2) +#else +#define DCHECK_EQ(val1, val2) CHECK_EQ(val1, val2) +#define DCHECK_NE(val1, val2) CHECK_NE(val1, val2) +#define DCHECK_LE(val1, val2) CHECK_LE(val1, val2) +#define DCHECK_LT(val1, val2) CHECK_LT(val1, val2) +#define DCHECK_GE(val1, val2) CHECK_GE(val1, val2) +#define DCHECK_GT(val1, val2) CHECK_GT(val1, val2) +#endif + + +#ifdef ERROR +#undef ERROR // may conflict with ERROR macro on windows +#endif +enum LogSeverity {INFO = -1, WARNING = -2, ERROR = -3, FATAL = -4}; + +// NOTE: we add a newline to the end of the output if it's not there already +inline void LogPrintf(int severity, const char* pat, va_list ap) { + // We write directly to the stderr file descriptor and avoid FILE + // buffering because that may invoke malloc() + char buf[600]; + vsnprintf(buf, sizeof(buf)-1, pat, ap); + if (buf[0] != '\0' && buf[strlen(buf)-1] != '\n') { + assert(strlen(buf)+1 < sizeof(buf)); + strcat(buf, "\n"); + } + WRITE_TO_STDERR(buf, strlen(buf)); + if ((severity) == FATAL) + abort(); // LOG(FATAL) indicates a big problem, so don't run atexit() calls +} + +// Note that since the order of global constructors is unspecified, +// global code that calls RAW_LOG may execute before FLAGS_verbose is set. +// Such code will run with verbosity == 0 no matter what. +#define VLOG_IS_ON(severity) (FLAGS_verbose >= severity) + +// In a better world, we'd use __VA_ARGS__, but VC++ 7 doesn't support it. +#define LOG_PRINTF(severity, pat) do { \ + if (VLOG_IS_ON(severity)) { \ + va_list ap; \ + va_start(ap, pat); \ + LogPrintf(severity, pat, ap); \ + va_end(ap); \ + } \ +} while (0) + +// RAW_LOG is the main function; some synonyms are used in unittests. +inline void RAW_LOG(int lvl, const char* pat, ...) { LOG_PRINTF(lvl, pat); } +inline void RAW_VLOG(int lvl, const char* pat, ...) { LOG_PRINTF(lvl, pat); } +inline void LOG(int lvl, const char* pat, ...) { LOG_PRINTF(lvl, pat); } +inline void VLOG(int lvl, const char* pat, ...) { LOG_PRINTF(lvl, pat); } +inline void LOG_IF(int lvl, bool cond, const char* pat, ...) { + if (cond) LOG_PRINTF(lvl, pat); +} + +// This isn't technically logging, but it's also IO and also is an +// attempt to be "raw" -- that is, to not use any higher-level libc +// routines that might allocate memory or (ideally) try to allocate +// locks. We use an opaque file handle (not necessarily an int) +// to allow even more low-level stuff in the future. +// Like other "raw" routines, these functions are best effort, and +// thus don't return error codes (except RawOpenForWriting()). +#if defined(_WIN32) || defined(__CYGWIN__) || defined(__CYGWIN32__) +#include <windows.h> +typedef HANDLE RawFD; +const RawFD kIllegalRawFD = INVALID_HANDLE_VALUE; +#else +typedef int RawFD; +const RawFD kIllegalRawFD = -1; // what open returns if it fails +#endif // defined(_WIN32) || defined(__CYGWIN__) || defined(__CYGWIN32__) + +RawFD RawOpenForWriting(const char* filename); // uses default permissions +void RawWrite(RawFD fd, const char* buf, size_t len); +void RawClose(RawFD fd); + +#endif // _LOGGING_H_ |