xref: /aosp_15_r20/external/bsdiff/logging.h (revision a3a45f308bd90ef1a6e6a5e8fb92fe449b895909)
1*a3a45f30SXin Li // Copyright 2017 The Chromium OS Authors. All rights reserved.
2*a3a45f30SXin Li // Use of this source code is governed by a BSD-style license that can be
3*a3a45f30SXin Li // found in the LICENSE file.
4*a3a45f30SXin Li 
5*a3a45f30SXin Li #ifndef _BSDIFF_LOGGING_H_
6*a3a45f30SXin Li #define _BSDIFF_LOGGING_H_
7*a3a45f30SXin Li 
8*a3a45f30SXin Li #include <string.h>
9*a3a45f30SXin Li 
10*a3a45f30SXin Li #include <iostream>
11*a3a45f30SXin Li #include <sstream>
12*a3a45f30SXin Li 
13*a3a45f30SXin Li // Simple error logging macro to avoid dependencies in other base libraries.
14*a3a45f30SXin Li #define LOG(severity) LogMessage(__FILE__, __LINE__, #severity).stream()
15*a3a45f30SXin Li 
16*a3a45f30SXin Li // A variant of LOG that also logs the current errno value.
17*a3a45f30SXin Li #define PLOG(severity) LogMessage(__FILE__, __LINE__, #severity, errno).stream()
18*a3a45f30SXin Li 
19*a3a45f30SXin Li // A temporarily scoped object used by LOG & PLOG.
20*a3a45f30SXin Li class LogMessage {
21*a3a45f30SXin Li  public:
22*a3a45f30SXin Li   LogMessage(const char* file, unsigned int line, const char* severity);
23*a3a45f30SXin Li 
24*a3a45f30SXin Li   LogMessage(const char* file,
25*a3a45f30SXin Li              unsigned int line,
26*a3a45f30SXin Li              const char* severity,
27*a3a45f30SXin Li              int error);
28*a3a45f30SXin Li 
29*a3a45f30SXin Li   ~LogMessage();
30*a3a45f30SXin Li 
31*a3a45f30SXin Li   // Returns the stream associated with the message, the LogMessage performs
32*a3a45f30SXin Li   // output when it goes out of scope.
stream()33*a3a45f30SXin Li   std::ostream& stream() { return stream_; }
34*a3a45f30SXin Li 
35*a3a45f30SXin Li  private:
36*a3a45f30SXin Li   std::ostringstream stream_;
37*a3a45f30SXin Li   int error_;  // The saved errno value.
38*a3a45f30SXin Li };
39*a3a45f30SXin Li 
40*a3a45f30SXin Li #endif  // _BSDIFF_LOGGING_H_
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