vlog.cc revision 72a454cd3513ac24fbdd0e0cb9ad70b86a99b801 
1// Copyright (c) 2010 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#include "base/vlog.h"
6
7#include "base/basictypes.h"
8#include "base/logging.h"
9#include "base/string_number_conversions.h"
10#include "base/string_split.h"
11
12namespace logging {
13
14const int VlogInfo::kDefaultVlogLevel = 0;
15
16struct VlogInfo::VmodulePattern {
17  enum MatchTarget { MATCH_MODULE, MATCH_FILE };
18
19  explicit VmodulePattern(const std::string& pattern);
20
21  VmodulePattern();
22
23  std::string pattern;
24  int vlog_level;
25  MatchTarget match_target;
26};
27
28VlogInfo::VmodulePattern::VmodulePattern(const std::string& pattern)
29    : pattern(pattern),
30      vlog_level(VlogInfo::kDefaultVlogLevel),
31      match_target(MATCH_MODULE) {
32  // If the pattern contains a {forward,back} slash, we assume that
33  // it's meant to be tested against the entire __FILE__ string.
34  std::string::size_type first_slash = pattern.find_first_of("\\/");
35  if (first_slash != std::string::npos)
36    match_target = MATCH_FILE;
37}
38
39VlogInfo::VmodulePattern::VmodulePattern()
40    : vlog_level(VlogInfo::kDefaultVlogLevel),
41      match_target(MATCH_MODULE) {}
42
43VlogInfo::VlogInfo(const std::string& v_switch,
44                   const std::string& vmodule_switch,
45                   int* min_log_level)
46    : min_log_level_(min_log_level) {
47  DCHECK(min_log_level != NULL);
48
49  typedef std::pair<std::string, std::string> KVPair;
50  int vlog_level = 0;
51  if (!v_switch.empty()) {
52    if (base::StringToInt(v_switch, &vlog_level)) {
53      SetMaxVlogLevel(vlog_level);
54    } else {
55      LOG(WARNING) << "Could not parse v switch \"" << v_switch << "\"";
56    }
57  }
58
59  std::vector<KVPair> kv_pairs;
60  if (!base::SplitStringIntoKeyValuePairs(
61          vmodule_switch, '=', ',', &kv_pairs)) {
62    LOG(WARNING) << "Could not fully parse vmodule switch \""
63                 << vmodule_switch << "\"";
64  }
65  for (std::vector<KVPair>::const_iterator it = kv_pairs.begin();
66       it != kv_pairs.end(); ++it) {
67    VmodulePattern pattern(it->first);
68    if (!base::StringToInt(it->second, &pattern.vlog_level)) {
69      LOG(WARNING) << "Parsed vlog level for \""
70                   << it->first << "=" << it->second
71                   << "\" as " << pattern.vlog_level;
72    }
73    vmodule_levels_.push_back(pattern);
74  }
75}
76
77VlogInfo::~VlogInfo() {}
78
79namespace {
80
81// Given a path, returns the basename with the extension chopped off
82// (and any -inl suffix).  We avoid using FilePath to minimize the
83// number of dependencies the logging system has.
84base::StringPiece GetModule(const base::StringPiece& file) {
85  base::StringPiece module(file);
86  base::StringPiece::size_type last_slash_pos =
87      module.find_last_of("\\/");
88  if (last_slash_pos != base::StringPiece::npos)
89    module.remove_prefix(last_slash_pos + 1);
90  base::StringPiece::size_type extension_start = module.rfind('.');
91  module = module.substr(0, extension_start);
92  static const char kInlSuffix[] = "-inl";
93  static const int kInlSuffixLen = arraysize(kInlSuffix) - 1;
94  if (module.ends_with(kInlSuffix))
95    module.remove_suffix(kInlSuffixLen);
96  return module;
97}
98
99}  // namespace
100
101int VlogInfo::GetVlogLevel(const base::StringPiece& file) const {
102  if (!vmodule_levels_.empty()) {
103    base::StringPiece module(GetModule(file));
104    for (std::vector<VmodulePattern>::const_iterator it =
105             vmodule_levels_.begin(); it != vmodule_levels_.end(); ++it) {
106      base::StringPiece target(
107          (it->match_target == VmodulePattern::MATCH_FILE) ? file : module);
108      if (MatchVlogPattern(target, it->pattern))
109        return it->vlog_level;
110    }
111  }
112  return GetMaxVlogLevel();
113}
114
115void VlogInfo::SetMaxVlogLevel(int level) {
116  // Log severity is the negative verbosity.
117  *min_log_level_ = -level;
118}
119
120int VlogInfo::GetMaxVlogLevel() const {
121  return -*min_log_level_;
122}
123
124bool MatchVlogPattern(const base::StringPiece& string,
125                      const base::StringPiece& vlog_pattern) {
126  base::StringPiece p(vlog_pattern);
127  base::StringPiece s(string);
128  // Consume characters until the next star.
129  while (!p.empty() && !s.empty() && (p[0] != '*')) {
130    switch (p[0]) {
131      // A slash (forward or back) must match a slash (forward or back).
132      case '/':
133      case '\\':
134        if ((s[0] != '/') && (s[0] != '\\'))
135          return false;
136        break;
137
138      // A '?' matches anything.
139      case '?':
140        break;
141
142      // Anything else must match literally.
143      default:
144        if (p[0] != s[0])
145          return false;
146        break;
147    }
148    p.remove_prefix(1), s.remove_prefix(1);
149  }
150
151  // An empty pattern here matches only an empty string.
152  if (p.empty())
153    return s.empty();
154
155  // Coalesce runs of consecutive stars.  There should be at least
156  // one.
157  while (!p.empty() && (p[0] == '*'))
158    p.remove_prefix(1);
159
160  // Since we moved past the stars, an empty pattern here matches
161  // anything.
162  if (p.empty())
163    return true;
164
165  // Since we moved past the stars and p is non-empty, if some
166  // non-empty substring of s matches p, then we ourselves match.
167  while (!s.empty()) {
168    if (MatchVlogPattern(s, p))
169      return true;
170    s.remove_prefix(1);
171  }
172
173  // Otherwise, we couldn't find a match.
174  return false;
175}
176
177}  // namespace
178