chromeos/system/name_value_pairs_parser.cc

   1 // Copyright (c) 2012 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 "chromeos/system/name_value_pairs_parser.h"
   6
   7 #include "base/command_line.h"
   8 #include "base/file_util.h"
   9 #include "base/files/file_path.h"
  10 #include "base/logging.h"
  11 #include "base/process/launch.h"
  12 #include "base/stl_util.h"
  13 #include "base/strings/string_tokenizer.h"
  14 #include "base/strings/string_util.h"
  15
  16 namespace chromeos {  // NOLINT
  17 namespace system {
  18
  19 namespace {
  20
  21 const char kQuoteChars[] = "\"";
  22 const char kTrimChars[] = "\" ";
  23
  24 bool GetToolOutput(int argc, const char* argv[], std::string& output) {
  25   DCHECK_GE(argc, 1);
  26
  27   if (!base::PathExists(base::FilePath(argv[0]))) {
  28     LOG(WARNING) << "Tool for statistics not found: " << argv[0];
  29     return false;
  30   }
  31
  32   std::vector<std::string> args;
  33   for (int argn = 0; argn < argc; ++argn)
  34     args.push_back(argv[argn]);
  35   if (!base::GetAppOutput(args, &output)) {
  36     LOG(WARNING) << "Error executing " << argv[0];
  37     return false;
  38   }
  39
  40   return true;
  41 }
  42
  43 }  // namespace
  44
  45 NameValuePairsParser::NameValuePairsParser(NameValueMap* map)
  46     : map_(map) {
  47 }
  48
  49 void NameValuePairsParser::AddNameValuePair(const std::string& key,
  50                                             const std::string& value) {
  51   if (!ContainsKey(*map_, key)) {
  52     (*map_)[key] = value;
  53     VLOG(1) << "name: " << key << ", value: " << value;
  54   } else {
  55     LOG(WARNING) << "Key " << key << " already has value " << (*map_)[key]
  56                  << ", ignoring new value: " << value;
  57   }
  58 }
  59
  60 bool NameValuePairsParser::ParseNameValuePairs(const std::string& in_string,
  61                                                const std::string& eq,
  62                                                const std::string& delim) {
  63   return ParseNameValuePairsWithComments(in_string, eq, delim, "");
  64 }
  65
  66 bool NameValuePairsParser::ParseNameValuePairsWithComments(
  67     const std::string& in_string,
  68     const std::string& eq,
  69     const std::string& delim,
  70     const std::string& comment_delim) {
  71   bool all_valid = true;
  72   // Set up the pair tokenizer.
  73   base::StringTokenizer pair_toks(in_string, delim);
  74   pair_toks.set_quote_chars(kQuoteChars);
  75   // Process token pairs.
  76   while (pair_toks.GetNext()) {
  77     std::string pair(pair_toks.token());
  78     // Anything before the first |eq| is the key, anything after is the value.
  79     // |eq| must exist.
  80     size_t eq_pos = pair.find(eq);
  81     if (eq_pos != std::string::npos) {
  82       // First |comment_delim| after |eq_pos| starts the comment.
  83       // A value of |std::string::npos| means that the value spans to the end
  84       // of |pair|.
  85       size_t value_size = std::string::npos;
  86       if (!comment_delim.empty()) {
  87         size_t comment_pos = pair.find(comment_delim, eq_pos + 1);
  88         if (comment_pos != std::string::npos)
  89           value_size = comment_pos - eq_pos - 1;
  90       }
  91
  92       std::string key;
  93       std::string value;
  94       base::TrimString(pair.substr(0, eq_pos), kTrimChars, &key);
  95       base::TrimString(pair.substr(eq_pos + 1, value_size), kTrimChars, &value);
  96
  97       if (!key.empty()) {
  98         AddNameValuePair(key, value);
  99         continue;
 100       }
 101     }
 102
 103     LOG(WARNING) << "Invalid token pair: " << pair << ". Ignoring.";
 104     all_valid = false;
 105   }
 106   return all_valid;
 107 }
 108
 109 bool NameValuePairsParser::GetSingleValueFromTool(int argc,
 110                                                   const char* argv[],
 111                                                   const std::string& key) {
 112   std::string output_string;
 113   if (!GetToolOutput(argc, argv, output_string))
 114     return false;
 115
 116   TrimWhitespaceASCII(output_string, TRIM_ALL, &output_string);
 117   AddNameValuePair(key, output_string);
 118   return true;
 119 }
 120
 121 bool NameValuePairsParser::GetNameValuePairsFromFile(
 122     const base::FilePath& file_path,
 123     const std::string& eq,
 124     const std::string& delim) {
 125   std::string contents;
 126   if (base::ReadFileToString(file_path, &contents)) {
 127     return ParseNameValuePairs(contents, eq, delim);
 128   } else {
 129     LOG(WARNING) << "Unable to read statistics file: " << file_path.value();
 130     return false;
 131   }
 132 }
 133
 134 bool NameValuePairsParser::ParseNameValuePairsFromTool(
 135     int argc,
 136     const char* argv[],
 137     const std::string& eq,
 138     const std::string& delim,
 139     const std::string& comment_delim) {
 140   std::string output_string;
 141   if (!GetToolOutput(argc, argv, output_string))
 142     return false;
 143
 144   return ParseNameValuePairsWithComments(
 145       output_string, eq, delim, comment_delim);
 146 }
 147
 148 }  // namespace system
 149 }  // namespace chromeos