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<uint16>* 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     int num;
  37     if (!StringToInt(*it, &num))
  38       return false;
  39
  40     if (num < 0)
  41       return false;
  42
  43     const uint16 max = 0xFFFF;
  44     if (num > max)
  45       return false;
  46
  47     // This throws out leading zeros for the first item only.
  48     if (it == numbers.begin() && IntToString(num) != *it)
  49       return false;
  50
  51     parsed->push_back(static_cast<uint16>(num));
  52   }
  53   return true;
  54 }
  55
  56 // Compares version components in |components1| with components in
  57 // |components2|. Returns -1, 0 or 1 if |components1| is less than, equal to,
  58 // or greater than |components2|, respectively.
  59 int CompareVersionComponents(const std::vector<uint16>& components1,
  60                              const std::vector<uint16>& components2) {
  61   const size_t count = std::min(components1.size(), components2.size());
  62   for (size_t i = 0; i < count; ++i) {
  63     if (components1[i] > components2[i])
  64       return 1;
  65     if (components1[i] < components2[i])
  66       return -1;
  67   }
  68   if (components1.size() > components2.size()) {
  69     for (size_t i = count; i < components1.size(); ++i) {
  70       if (components1[i] > 0)
  71         return 1;
  72     }
  73   } else if (components1.size() < components2.size()) {
  74     for (size_t i = count; i < components2.size(); ++i) {
  75       if (components2[i] > 0)
  76         return -1;
  77     }
  78   }
  79   return 0;
  80 }
  81
  82 }  // namespace
  83
  84 Version::Version() {
  85 }
  86
  87 Version::~Version() {
  88 }
  89
  90 Version::Version(const std::string& version_str) {
  91   std::vector<uint16> parsed;
  92   if (!ParseVersionNumbers(version_str, &parsed))
  93     return;
  94
  95   components_.swap(parsed);
  96 }
  97
  98 bool Version::IsValid() const {
  99   return (!components_.empty());
 100 }
 101
 102 // static
 103 bool Version::IsValidWildcardString(const std::string& wildcard_string) {
 104   std::string version_string = wildcard_string;
 105   if (EndsWith(wildcard_string.c_str(), ".*", false))
 106     version_string = wildcard_string.substr(0, wildcard_string.size() - 2);
 107
 108   Version version(version_string);
 109   return version.IsValid();
 110 }
 111
 112 bool Version::IsOlderThan(const std::string& version_str) const {
 113   Version proposed_ver(version_str);
 114   if (!proposed_ver.IsValid())
 115     return false;
 116   return (CompareTo(proposed_ver) < 0);
 117 }
 118
 119 int Version::CompareToWildcardString(const std::string& wildcard_string) const {
 120   DCHECK(IsValid());
 121   DCHECK(Version::IsValidWildcardString(wildcard_string));
 122
 123   // Default behavior if the string doesn't end with a wildcard.
 124   if (!EndsWith(wildcard_string.c_str(), ".*", false)) {
 125     Version version(wildcard_string);
 126     DCHECK(version.IsValid());
 127     return CompareTo(version);
 128   }
 129
 130   std::vector<uint16> parsed;
 131   const bool success = ParseVersionNumbers(
 132       wildcard_string.substr(0, wildcard_string.length() - 2), &parsed);
 133   DCHECK(success);
 134   const int comparison = CompareVersionComponents(components_, parsed);
 135   // If the version is smaller than the wildcard version's |parsed| vector,
 136   // then the wildcard has no effect (e.g. comparing 1.2.3 and 1.3.*) and the
 137   // version is still smaller. Same logic for equality (e.g. comparing 1.2.2 to
 138   // 1.2.2.* is 0 regardless of the wildcard). Under this logic,
 139   // 1.2.0.0.0.0 compared to 1.2.* is 0.
 140   if (comparison == -1 || comparison == 0)
 141     return comparison;
 142
 143   // Catch the case where the digits of |parsed| are found in |components_|,
 144   // which means that the two are equal since |parsed| has a trailing "*".
 145   // (e.g. 1.2.3 vs. 1.2.* will return 0). All other cases return 1 since
 146   // components is greater (e.g. 3.2.3 vs 1.*).
 147   DCHECK_GT(parsed.size(), 0UL);
 148   const size_t min_num_comp = std::min(components_.size(), parsed.size());
 149   for (size_t i = 0; i < min_num_comp; ++i) {
 150     if (components_[i] != parsed[i])
 151       return 1;
 152   }
 153   return 0;
 154 }
 155
 156 bool Version::Equals(const Version& that) const {
 157   DCHECK(IsValid());
 158   DCHECK(that.IsValid());
 159   return (CompareTo(that) == 0);
 160 }
 161
 162 int Version::CompareTo(const Version& other) const {
 163   DCHECK(IsValid());
 164   DCHECK(other.IsValid());
 165   return CompareVersionComponents(components_, other.components_);
 166 }
 167
 168 const std::string Version::GetString() const {
 169   DCHECK(IsValid());
 170   std::string version_str;
 171   size_t count = components_.size();
 172   for (size_t i = 0; i < count - 1; ++i) {
 173     version_str.append(IntToString(components_[i]));
 174     version_str.append(".");
 175   }
 176   version_str.append(IntToString(components_[count - 1]));
 177   return version_str;
 178 }
 179
 180 }  // namespace base