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