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<StringPiece> numbers =
  28       SplitStringPiece(version_str, ".", KEEP_WHITESPACE, SPLIT_WANT_ALL);
  29   if (numbers.empty())
  30     return false;
  31
  32   for (auto it = numbers.begin(); it != numbers.end(); ++it) {
  33     if (StartsWith(*it, "+", CompareCase::SENSITIVE))
  34       return false;
  35
  36     // TODO(brettw) when we have a StringPiece version of StringToUint, delete
  37     // this string conversion.
  38     unsigned int num;
  39     if (!StringToUint(*it, &num))
  40       return false;
  41
  42     // This throws out leading zeros for the first item only.
  43     if (it == numbers.begin() && UintToString(num) != *it)
  44       return false;
  45
  46     // StringToUint returns unsigned int but Version fields are uint32_t.
  47     static_assert(sizeof (uint32_t) == sizeof (unsigned int),
  48         "uint32_t must be same as unsigned int");
  49     parsed->push_back(num);
  50   }
  51   return true;
  52 }
  53
  54 // Compares version components in |components1| with components in
  55 // |components2|. Returns -1, 0 or 1 if |components1| is less than, equal to,
  56 // or greater than |components2|, respectively.
  57 int CompareVersionComponents(const std::vector<uint32_t>& components1,
  58                              const std::vector<uint32_t>& components2) {
  59   const size_t count = std::min(components1.size(), components2.size());
  60   for (size_t i = 0; i < count; ++i) {
  61     if (components1[i] > components2[i])
  62       return 1;
  63     if (components1[i] < components2[i])
  64       return -1;
  65   }
  66   if (components1.size() > components2.size()) {
  67     for (size_t i = count; i < components1.size(); ++i) {
  68       if (components1[i] > 0)
  69         return 1;
  70     }
  71   } else if (components1.size() < components2.size()) {
  72     for (size_t i = count; i < components2.size(); ++i) {
  73       if (components2[i] > 0)
  74         return -1;
  75     }
  76   }
  77   return 0;
  78 }
  79
  80 }  // namespace
  81
  82 Version::Version() {
  83 }
  84
  85 Version::~Version() {
  86 }
  87
  88 Version::Version(const std::string& version_str) {
  89   std::vector<uint32_t> parsed;
  90   if (!ParseVersionNumbers(version_str, &parsed))
  91     return;
  92
  93   components_.swap(parsed);
  94 }
  95
  96 bool Version::IsValid() const {
  97   return (!components_.empty());
  98 }
  99
 100 // static
 101 bool Version::IsValidWildcardString(const std::string& wildcard_string) {
 102   std::string version_string = wildcard_string;
 103   if (EndsWith(version_string, ".*", CompareCase::SENSITIVE))
 104     version_string.resize(version_string.size() - 2);
 105
 106   Version version(version_string);
 107   return version.IsValid();
 108 }
 109
 110 bool Version::IsOlderThan(const std::string& version_str) const {
 111   Version proposed_ver(version_str);
 112   if (!proposed_ver.IsValid())
 113     return false;
 114   return (CompareTo(proposed_ver) < 0);
 115 }
 116
 117 int Version::CompareToWildcardString(const std::string& wildcard_string) const {
 118   DCHECK(IsValid());
 119   DCHECK(Version::IsValidWildcardString(wildcard_string));
 120
 121   // Default behavior if the string doesn't end with a wildcard.
 122   if (!EndsWith(wildcard_string, ".*", CompareCase::SENSITIVE)) {
 123     Version version(wildcard_string);
 124     DCHECK(version.IsValid());
 125     return CompareTo(version);
 126   }
 127
 128   std::vector<uint32_t> parsed;
 129   const bool success = ParseVersionNumbers(
 130       wildcard_string.substr(0, wildcard_string.length() - 2), &parsed);
 131   DCHECK(success);
 132   const int comparison = CompareVersionComponents(components_, parsed);
 133   // If the version is smaller than the wildcard version's |parsed| vector,
 134   // then the wildcard has no effect (e.g. comparing 1.2.3 and 1.3.*) and the
 135   // version is still smaller. Same logic for equality (e.g. comparing 1.2.2 to
 136   // 1.2.2.* is 0 regardless of the wildcard). Under this logic,
 137   // 1.2.0.0.0.0 compared to 1.2.* is 0.
 138   if (comparison == -1 || comparison == 0)
 139     return comparison;
 140
 141   // Catch the case where the digits of |parsed| are found in |components_|,
 142   // which means that the two are equal since |parsed| has a trailing "*".
 143   // (e.g. 1.2.3 vs. 1.2.* will return 0). All other cases return 1 since
 144   // components is greater (e.g. 3.2.3 vs 1.*).
 145   DCHECK_GT(parsed.size(), 0UL);
 146   const size_t min_num_comp = std::min(components_.size(), parsed.size());
 147   for (size_t i = 0; i < min_num_comp; ++i) {
 148     if (components_[i] != parsed[i])
 149       return 1;
 150   }
 151   return 0;
 152 }
 153
 154 bool Version::Equals(const Version& that) const {
 155   DCHECK(IsValid());
 156   DCHECK(that.IsValid());
 157   return (CompareTo(that) == 0);
 158 }
 159
 160 int Version::CompareTo(const Version& other) const {
 161   DCHECK(IsValid());
 162   DCHECK(other.IsValid());
 163   return CompareVersionComponents(components_, other.components_);
 164 }
 165
 166 const std::string Version::GetString() const {
 167   DCHECK(IsValid());
 168   std::string version_str;
 169   size_t count = components_.size();
 170   for (size_t i = 0; i < count - 1; ++i) {
 171     version_str.append(UintToString(components_[i]));
 172     version_str.append(".");
 173   }
 174   version_str.append(UintToString(components_[count - 1]));
 175   return version_str;
 176 }
 177
 178 }  // namespace base