base/version.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 "base/version.h"
   6
   7 #include <stddef.h>
   8
   9 #include <algorithm>
  10
  11 #include "base/logging.h"
  12 #include "base/strings/string_number_conversions.h"
  13 #include "base/strings/string_split.h"
  14 #include "base/strings/string_util.h"
  15
  16 namespace base {
  17
  18 namespace {
  19
  20 // Parses the |numbers| vector representing the different numbers
  21 // inside the version string and constructs a vector of valid integers. It stops
  22 // when it reaches an invalid item (including the wildcard character). |parsed|
  23 // is the resulting integer vector. Function returns true if all numbers were
  24 // parsed successfully, false otherwise.
  25 bool ParseVersionNumbers(const std::string& version_str,
  26                          std::vector<uint32_t>* parsed) {
  27   std::vector<std::string> numbers;
  28   SplitString(version_str, '.', &numbers);
  29   if (numbers.empty())
  30     return false;
  31
  32   for (std::vector<std::string>::const_iterator it = numbers.begin();
  33        it != numbers.end(); ++it) {
  34     if (StartsWithASCII(*it, "+", false))
  35       return false;
  36     unsigned int num;
  37     if (!StringToUint(*it, &num))
  38       return false;
  39
  40     // This throws out leading zeros for the first item only.
  41     if (it == numbers.begin() && UintToString(num) != *it)
  42       return false;
  43
  44     // StringToUint returns unsigned int but Version fields are uint32_t.
  45     static_assert(sizeof (uint32_t) == sizeof (unsigned int),
  46         "uint32_t must be same as unsigned int");
  47     parsed->push_back(num);
  48   }
  49   return true;
  50 }
  51
  52 // Compares version components in |components1| with components in
  53 // |components2|. Returns -1, 0 or 1 if |components1| is less than, equal to,
  54 // or greater than |components2|, respectively.
  55 int CompareVersionComponents(const std::vector<uint32_t>& components1,
  56                              const std::vector<uint32_t>& components2) {
  57   const size_t count = std::min(components1.size(), components2.size());
  58   for (size_t i = 0; i < count; ++i) {
  59     if (components1[i] > components2[i])
  60       return 1;
  61     if (components1[i] < components2[i])
  62       return -1;
  63   }
  64   if (components1.size() > components2.size()) {
  65     for (size_t i = count; i < components1.size(); ++i) {
  66       if (components1[i] > 0)
  67         return 1;
  68     }
  69   } else if (components1.size() < components2.size()) {
  70     for (size_t i = count; i < components2.size(); ++i) {
  71       if (components2[i] > 0)
  72         return -1;
  73     }
  74   }
  75   return 0;
  76 }
  77
  78 }  // namespace
  79
  80 Version::Version() {
  81 }
  82
  83 Version::~Version() {
  84 }
  85
  86 Version::Version(const std::string& version_str) {
  87   std::vector<uint32_t> parsed;
  88   if (!ParseVersionNumbers(version_str, &parsed))
  89     return;
  90
  91   components_.swap(parsed);
  92 }
  93
  94 bool Version::IsValid() const {
  95   return (!components_.empty());
  96 }
  97
  98 // static
  99 bool Version::IsValidWildcardString(const std::string& wildcard_string) {
 100   std::string version_string = wildcard_string;
 101   if (EndsWith(wildcard_string.c_str(), ".*", false))
 102     version_string = wildcard_string.substr(0, wildcard_string.size() - 2);
 103
 104   Version version(version_string);
 105   return version.IsValid();
 106 }
 107
 108 bool Version::IsOlderThan(const std::string& version_str) const {
 109   Version proposed_ver(version_str);
 110   if (!proposed_ver.IsValid())
 111     return false;
 112   return (CompareTo(proposed_ver) < 0);
 113 }
 114
 115 int Version::CompareToWildcardString(const std::string& wildcard_string) const {
 116   DCHECK(IsValid());
 117   DCHECK(Version::IsValidWildcardString(wildcard_string));
 118
 119   // Default behavior if the string doesn't end with a wildcard.
 120   if (!EndsWith(wildcard_string.c_str(), ".*", false)) {
 121     Version version(wildcard_string);
 122     DCHECK(version.IsValid());
 123     return CompareTo(version);
 124   }
 125
 126   std::vector<uint32_t> parsed;
 127   const bool success = ParseVersionNumbers(
 128       wildcard_string.substr(0, wildcard_string.length() - 2), &parsed);
 129   DCHECK(success);
 130   const int comparison = CompareVersionComponents(components_, parsed);
 131   // If the version is smaller than the wildcard version's |parsed| vector,
 132   // then the wildcard has no effect (e.g. comparing 1.2.3 and 1.3.*) and the
 133   // version is still smaller. Same logic for equality (e.g. comparing 1.2.2 to
 134   // 1.2.2.* is 0 regardless of the wildcard). Under this logic,
 135   // 1.2.0.0.0.0 compared to 1.2.* is 0.
 136   if (comparison == -1 || comparison == 0)
 137     return comparison;
 138
 139   // Catch the case where the digits of |parsed| are found in |components_|,
 140   // which means that the two are equal since |parsed| has a trailing "*".
 141   // (e.g. 1.2.3 vs. 1.2.* will return 0). All other cases return 1 since
 142   // components is greater (e.g. 3.2.3 vs 1.*).
 143   DCHECK_GT(parsed.size(), 0UL);
 144   const size_t min_num_comp = std::min(components_.size(), parsed.size());
 145   for (size_t i = 0; i < min_num_comp; ++i) {
 146     if (components_[i] != parsed[i])
 147       return 1;
 148   }
 149   return 0;
 150 }
 151
 152 bool Version::Equals(const Version& that) const {
 153   DCHECK(IsValid());
 154   DCHECK(that.IsValid());
 155   return (CompareTo(that) == 0);
 156 }
 157
 158 int Version::CompareTo(const Version& other) const {
 159   DCHECK(IsValid());
 160   DCHECK(other.IsValid());
 161   return CompareVersionComponents(components_, other.components_);
 162 }
 163
 164 const std::string Version::GetString() const {
 165   DCHECK(IsValid());
 166   std::string version_str;
 167   size_t count = components_.size();
 168   for (size_t i = 0; i < count - 1; ++i) {
 169     version_str.append(IntToString(components_[i]));
 170     version_str.append(".");
 171   }
 172   version_str.append(IntToString(components_[count - 1]));
 173   return version_str;
 174 }
 175
 176 }  // namespace base