1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef BASE_VLOG_H_
6#define BASE_VLOG_H_
7
8#include <string>
9#include <vector>
10
11#include "base/base_export.h"
12#include "base/basictypes.h"
13#include "base/strings/string_piece.h"
14
15namespace logging {
16
17// A helper class containing all the settings for vlogging.
18class BASE_EXPORT VlogInfo {
19 public:
20  static const int kDefaultVlogLevel;
21
22  // |v_switch| gives the default maximal active V-logging level; 0 is
23  // the default.  Normally positive values are used for V-logging
24  // levels.
25  //
26  // |vmodule_switch| gives the per-module maximal V-logging levels to
27  // override the value given by |v_switch|.
28  // E.g. "my_module=2,foo*=3" would change the logging level for all
29  // code in source files "my_module.*" and "foo*.*" ("-inl" suffixes
30  // are also disregarded for this matching).
31  //
32  // |log_severity| points to an int that stores the log level. If a valid
33  // |v_switch| is provided, it will set the log level, and the default
34  // vlog severity will be read from there..
35  //
36  // Any pattern containing a forward or backward slash will be tested
37  // against the whole pathname and not just the module.  E.g.,
38  // "*/foo/bar/*=2" would change the logging level for all code in
39  // source files under a "foo/bar" directory.
40  VlogInfo(const std::string& v_switch,
41           const std::string& vmodule_switch,
42           int* min_log_level);
43  ~VlogInfo();
44
45  // Returns the vlog level for a given file (usually taken from
46  // __FILE__).
47  int GetVlogLevel(const base::StringPiece& file) const;
48
49 private:
50  void SetMaxVlogLevel(int level);
51  int GetMaxVlogLevel() const;
52
53  // VmodulePattern holds all the information for each pattern parsed
54  // from |vmodule_switch|.
55  struct VmodulePattern;
56  std::vector<VmodulePattern> vmodule_levels_;
57  int* min_log_level_;
58
59  DISALLOW_COPY_AND_ASSIGN(VlogInfo);
60};
61
62// Returns true if the string passed in matches the vlog pattern.  The
63// vlog pattern string can contain wildcards like * and ?.  ? matches
64// exactly one character while * matches 0 or more characters.  Also,
65// as a special case, a / or \ character matches either / or \.
66//
67// Examples:
68//   "kh?n" matches "khan" but not "khn" or "khaan"
69//   "kh*n" matches "khn", "khan", or even "khaaaaan"
70//   "/foo\bar" matches "/foo/bar", "\foo\bar", or "/foo\bar"
71//     (disregarding C escaping rules)
72BASE_EXPORT bool MatchVlogPattern(const base::StringPiece& string,
73                                  const base::StringPiece& vlog_pattern);
74
75}  // namespace logging
76
77#endif  // BASE_VLOG_H_
78