xpcom/base/nsVersionComparator.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 // NB: This code may be used from non-XPCOM code, in particular, the
   8 // standalone updater executable.
   9
  10 #ifndef nsVersionComparator_h__
  11 #define nsVersionComparator_h__
  12
  13 #include "mozilla/Char16.h"
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <assert.h>
  17 #if defined(XP_WIN) && !defined(UPDATER_NO_STRING_GLUE_STL)
  18 #  include <wchar.h>
  19 #  include "nsString.h"
  20 #endif
  21
  22 /**
  23  * In order to compare version numbers in Mozilla, you need to use the
  24  * mozilla::Version class.  You can construct an object of this type by passing
  25  * in a string version number to the constructor.  Objects of this type can be
  26  * compared using the standard comparison operators.
  27  *
  28  * For example, let's say that you want to make sure that a given version
  29  * number is not older than 15.a2.  Here's how you would write a function to
  30  * do that.
  31  *
  32  * bool IsVersionValid(const char* version) {
  33  *   return mozilla::Version("15.a2") <= mozilla::Version(version);
  34  * }
  35  *
  36  * Or, since Version's constructor is implicit, you can simplify this code:
  37  *
  38  * bool IsVersionValid(const char* version) {
  39  *   return mozilla::Version("15.a2") <= version;
  40  * }
  41  */
  42
  43 namespace mozilla {
  44
  45 /**
  46  * Compares the version strings provided.
  47  *
  48  * Returns 0 if the versions match, < 0 if aStrB > aStrA and > 0 if
  49  * aStrA > aStrB.
  50  */
  51 int32_t CompareVersions(const char* aStrA, const char* aStrB);
  52
  53 #ifdef XP_WIN
  54 /**
  55  * As above but for wide character strings.
  56  */
  57 int32_t CompareVersions(const char16_t* aStrA, const char16_t* aStrB);
  58 #endif
  59
  60 struct Version {
  61   explicit Version(const char* aVersionString) {
  62     versionContent = strdup(aVersionString);
  63   }
  64
  65   const char* ReadContent() const { return versionContent; }
  66
  67   ~Version() { free(versionContent); }
  68
  69   bool operator<(const Version& aRhs) const {
  70     return CompareVersions(versionContent, aRhs.ReadContent()) < 0;
  71   }
  72   bool operator<=(const Version& aRhs) const {
  73     return CompareVersions(versionContent, aRhs.ReadContent()) < 1;
  74   }
  75   bool operator>(const Version& aRhs) const {
  76     return CompareVersions(versionContent, aRhs.ReadContent()) > 0;
  77   }
  78   bool operator>=(const Version& aRhs) const {
  79     return CompareVersions(versionContent, aRhs.ReadContent()) > -1;
  80   }
  81   bool operator==(const Version& aRhs) const {
  82     return CompareVersions(versionContent, aRhs.ReadContent()) == 0;
  83   }
  84   bool operator!=(const Version& aRhs) const {
  85     return CompareVersions(versionContent, aRhs.ReadContent()) != 0;
  86   }
  87   bool operator<(const char* aRhs) const {
  88     return CompareVersions(versionContent, aRhs) < 0;
  89   }
  90   bool operator<=(const char* aRhs) const {
  91     return CompareVersions(versionContent, aRhs) < 1;
  92   }
  93   bool operator>(const char* aRhs) const {
  94     return CompareVersions(versionContent, aRhs) > 0;
  95   }
  96   bool operator>=(const char* aRhs) const {
  97     return CompareVersions(versionContent, aRhs) > -1;
  98   }
  99   bool operator==(const char* aRhs) const {
 100     return CompareVersions(versionContent, aRhs) == 0;
 101   }
 102   bool operator!=(const char* aRhs) const {
 103     return CompareVersions(versionContent, aRhs) != 0;
 104   }
 105
 106  private:
 107   char* versionContent;
 108 };
 109
 110 }  // namespace mozilla
 111
 112 #endif  // nsVersionComparator_h__