1// Copyright (c) 2006, Google Inc.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8//     * Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10//     * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14//     * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29//
30// Author: Maxim Lifantsev
31//
32// Thread-safe logging routines that do not allocate any memory or
33// acquire any locks, and can therefore be used by low-level memory
34// allocation and synchronization code.
35
36#ifndef BASE_RAW_LOGGING_H_
37#define BASE_RAW_LOGGING_H_
38
39#include <ctime>
40
41@ac_google_start_namespace@
42
43#include "glog/log_severity.h"
44#include "glog/vlog_is_on.h"
45
46// Annoying stuff for windows -- makes sure clients can import these functions
47#ifndef GOOGLE_GLOG_DLL_DECL
48# if defined(_WIN32) && !defined(__CYGWIN__)
49#   define GOOGLE_GLOG_DLL_DECL  __declspec(dllimport)
50# else
51#   define GOOGLE_GLOG_DLL_DECL
52# endif
53#endif
54
55// This is similar to LOG(severity) << format... and VLOG(level) << format..,
56// but
57// * it is to be used ONLY by low-level modules that can't use normal LOG()
58// * it is desiged to be a low-level logger that does not allocate any
59//   memory and does not need any locks, hence:
60// * it logs straight and ONLY to STDERR w/o buffering
61// * it uses an explicit format and arguments list
62// * it will silently chop off really long message strings
63// Usage example:
64//   RAW_LOG(ERROR, "Failed foo with %i: %s", status, error);
65//   RAW_VLOG(3, "status is %i", status);
66// These will print an almost standard log lines like this to stderr only:
67//   E20200821 211317 file.cc:123] RAW: Failed foo with 22: bad_file
68//   I20200821 211317 file.cc:142] RAW: status is 20
69#define RAW_LOG(severity, ...) \
70  do { \
71    switch (@ac_google_namespace@::GLOG_ ## severity) {  \
72      case 0: \
73        RAW_LOG_INFO(__VA_ARGS__); \
74        break; \
75      case 1: \
76        RAW_LOG_WARNING(__VA_ARGS__); \
77        break; \
78      case 2: \
79        RAW_LOG_ERROR(__VA_ARGS__); \
80        break; \
81      case 3: \
82        RAW_LOG_FATAL(__VA_ARGS__); \
83        break; \
84      default: \
85        break; \
86    } \
87  } while (0)
88
89// The following STRIP_LOG testing is performed in the header file so that it's
90// possible to completely compile out the logging code and the log messages.
91#if STRIP_LOG == 0
92#define RAW_VLOG(verboselevel, ...) \
93  do { \
94    if (VLOG_IS_ON(verboselevel)) { \
95      RAW_LOG_INFO(__VA_ARGS__); \
96    } \
97  } while (0)
98#else
99#define RAW_VLOG(verboselevel, ...) RawLogStub__(0, __VA_ARGS__)
100#endif // STRIP_LOG == 0
101
102#if STRIP_LOG == 0
103#define RAW_LOG_INFO(...) @ac_google_namespace@::RawLog__(@ac_google_namespace@::GLOG_INFO, \
104                                   __FILE__, __LINE__, __VA_ARGS__)
105#else
106#define RAW_LOG_INFO(...) @ac_google_namespace@::RawLogStub__(0, __VA_ARGS__)
107#endif // STRIP_LOG == 0
108
109#if STRIP_LOG <= 1
110#define RAW_LOG_WARNING(...) @ac_google_namespace@::RawLog__(@ac_google_namespace@::GLOG_WARNING,   \
111                                      __FILE__, __LINE__, __VA_ARGS__)
112#else
113#define RAW_LOG_WARNING(...) @ac_google_namespace@::RawLogStub__(0, __VA_ARGS__)
114#endif // STRIP_LOG <= 1
115
116#if STRIP_LOG <= 2
117#define RAW_LOG_ERROR(...) @ac_google_namespace@::RawLog__(@ac_google_namespace@::GLOG_ERROR,       \
118                                    __FILE__, __LINE__, __VA_ARGS__)
119#else
120#define RAW_LOG_ERROR(...) @ac_google_namespace@::RawLogStub__(0, __VA_ARGS__)
121#endif // STRIP_LOG <= 2
122
123#if STRIP_LOG <= 3
124#define RAW_LOG_FATAL(...) @ac_google_namespace@::RawLog__(@ac_google_namespace@::GLOG_FATAL,       \
125                                    __FILE__, __LINE__, __VA_ARGS__)
126#else
127#define RAW_LOG_FATAL(...) \
128  do { \
129    @ac_google_namespace@::RawLogStub__(0, __VA_ARGS__);        \
130    exit(1); \
131  } while (0)
132#endif // STRIP_LOG <= 3
133
134// Similar to CHECK(condition) << message,
135// but for low-level modules: we use only RAW_LOG that does not allocate memory.
136// We do not want to provide args list here to encourage this usage:
137//   if (!cond)  RAW_LOG(FATAL, "foo ...", hard_to_compute_args);
138// so that the args are not computed when not needed.
139#define RAW_CHECK(condition, message)                                   \
140  do {                                                                  \
141    if (!(condition)) {                                                 \
142      RAW_LOG(FATAL, "Check %s failed: %s", #condition, message);       \
143    }                                                                   \
144  } while (0)
145
146// Debug versions of RAW_LOG and RAW_CHECK
147#ifndef NDEBUG
148
149#define RAW_DLOG(severity, ...) RAW_LOG(severity, __VA_ARGS__)
150#define RAW_DCHECK(condition, message) RAW_CHECK(condition, message)
151
152#else  // NDEBUG
153
154#define RAW_DLOG(severity, ...)                                 \
155  while (false)                                                 \
156    RAW_LOG(severity, __VA_ARGS__)
157#define RAW_DCHECK(condition, message) \
158  while (false) \
159    RAW_CHECK(condition, message)
160
161#endif  // NDEBUG
162
163// Stub log function used to work around for unused variable warnings when
164// building with STRIP_LOG > 0.
165static inline void RawLogStub__(int /* ignored */, ...) {
166}
167
168// Helper function to implement RAW_LOG and RAW_VLOG
169// Logs format... at "severity" level, reporting it
170// as called from file:line.
171// This does not allocate memory or acquire locks.
172GOOGLE_GLOG_DLL_DECL void RawLog__(LogSeverity severity,
173                                   const char* file,
174                                   int line,
175                                   const char* format, ...)
176   @ac_cv___attribute___printf_4_5@;
177
178@ac_google_end_namespace@
179
180#endif  // BASE_RAW_LOGGING_H_
181