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 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 #include "nsVersionComparator.h"

 #include <stdlib.h>

 #include <string.h>

 #include <stdint.h>

 #if defined(XP_WIN) && !defined(UPDATER_NO_STRING_GLUE_STL)

 #include <wchar.h>

 #include "nsStringGlue.h"

 #endif

 struct VersionPart {

   int32_t     numA;

   const char *strB;    // NOT null-terminated, can be a null pointer

   uint32_t    strBlen;

   int32_t     numC;

   char       *extraD;  // null-terminated

 };

 #ifdef XP_WIN

 struct VersionPartW {

   int32_t     numA;

   wchar_t    *strB;    // NOT null-terminated, can be a null pointer

   uint32_t    strBlen;

   int32_t     numC;

   wchar_t    *extraD;  // null-terminated

 };

 #endif

 /**

  * Parse a version part into a number and "extra text".

  *

  * @returns A pointer to the next versionpart, or null if none.

  */

 static char*

 ParseVP(char *part, VersionPart &result)

 {

   char *dot;

   result.numA = 0;

   result.strB = nullptr;

   result.strBlen = 0;

   result.numC = 0;

   result.extraD = nullptr;

   if (!part)

     return part;

   dot = strchr(part, '.');

   if (dot)

     *dot = '\0';

   if (part[0] == '*' && part[1] == '\0') {

     result.numA = INT32_MAX;

     result.strB = "";

   }

   else {

     result.numA = strtol(part, const_cast<char**>(&result.strB), 10);

   }

   if (!*result.strB) {

     result.strB = nullptr;

     result.strBlen = 0;

   }

   else {

     if (result.strB[0] == '+') {

       static const char kPre[] = "pre";

       ++result.numA;

       result.strB = kPre;

       result.strBlen = sizeof(kPre) - 1;

     }

     else {

       const char *numstart = strpbrk(result.strB, "0123456789+-");

       if (!numstart) {

 	result.strBlen = strlen(result.strB);

       }

       else {

 	result.strBlen = numstart - result.strB;

 	result.numC = strtol(numstart, &result.extraD, 10);

 	if (!*result.extraD)

 	  result.extraD = nullptr;

       }

     }

   }

   if (dot) {

     ++dot;

     if (!*dot)

       dot = nullptr;

   }

   return dot;

 }

 /**

  * Parse a version part into a number and "extra text".

  *

  * @returns A pointer to the next versionpart, or null if none.

  */

 #ifdef XP_WIN

 static wchar_t*

 ParseVP(wchar_t *part, VersionPartW &result)

 {

   wchar_t *dot;

   result.numA = 0;

   result.strB = nullptr;

   result.strBlen = 0;

   result.numC = 0;

   result.extraD = nullptr;

   if (!part)

     return part;

   dot = wcschr(part, '.');

   if (dot)

     *dot = '\0';

   if (part[0] == '*' && part[1] == '\0') {

     result.numA = INT32_MAX;

     result.strB = L"";

   }

   else {

     result.numA = wcstol(part, const_cast<wchar_t**>(&result.strB), 10);

   }

   if (!*result.strB) {

     result.strB = nullptr;

     result.strBlen = 0;

   }

   else {

     if (result.strB[0] == '+') {

       static wchar_t kPre[] = L"pre";

       ++result.numA;

       result.strB = kPre;

       result.strBlen = sizeof(kPre) - 1;

     }

     else {

       const wchar_t *numstart = wcspbrk(result.strB, L"0123456789+-");

       if (!numstart) {

 	result.strBlen = wcslen(result.strB);

       }

       else {

 	result.strBlen = numstart - result.strB;

 	result.numC = wcstol(numstart, &result.extraD, 10);

 	if (!*result.extraD)

 	  result.extraD = nullptr;

       }

     }

   }

   if (dot) {

     ++dot;

     if (!*dot)

       dot = nullptr;

   }

   return dot;

 }

 #endif

 // compare two null-terminated strings, which may be null pointers

 static int32_t

 ns_strcmp(const char *str1, const char *str2)

 {

   // any string is *before* no string

   if (!str1)

     return str2 != 0;

   if (!str2)

     return -1;

   return strcmp(str1, str2);

 }

 // compare two length-specified string, which may be null pointers

 static int32_t

 ns_strnncmp(const char *str1, uint32_t len1, const char *str2, uint32_t len2)

 {

   // any string is *before* no string

   if (!str1)

     return str2 != 0;

   if (!str2)

     return -1;

   for (; len1 && len2; --len1, --len2, ++str1, ++str2) {

     if (*str1 < *str2)

       return -1;

     if (*str1 > *str2)

       return 1;

   }

   if (len1 == 0)

     return len2 == 0 ? 0 : -1;

   return 1;

 }

 // compare two int32_t

 static int32_t

 ns_cmp(int32_t n1, int32_t n2)

 {

   if (n1 < n2)

     return -1;

   return n1 != n2;

 }

 /**

  * Compares two VersionParts

  */

 static int32_t

 CompareVP(VersionPart &v1, VersionPart &v2)

 {

   int32_t r = ns_cmp(v1.numA, v2.numA);

   if (r)

     return r;

   r = ns_strnncmp(v1.strB, v1.strBlen, v2.strB, v2.strBlen);

   if (r)

     return r;

   r = ns_cmp(v1.numC, v2.numC);

   if (r)

     return r;

   return ns_strcmp(v1.extraD, v2.extraD);

 }

 /**

  * Compares two VersionParts

  */

 #ifdef XP_WIN

 static int32_t

 CompareVP(VersionPartW &v1, VersionPartW &v2)

 {

   int32_t r = ns_cmp(v1.numA, v2.numA);

   if (r)

     return r;

   r = wcsncmp(v1.strB, v2.strB, XPCOM_MIN(v1.strBlen,v2.strBlen));

   if (r)

     return r;

   r = ns_cmp(v1.numC, v2.numC);

   if (r)

     return r;

   if (!v1.extraD)

     return v2.extraD != 0;

   if (!v2.extraD)

     return -1;

   return wcscmp(v1.extraD, v2.extraD);

 }

 #endif

 namespace mozilla {

 #ifdef XP_WIN

 int32_t

 CompareVersions(const char16_t *A, const char16_t *B)

 {

   wchar_t *A2 = wcsdup(char16ptr_t(A));

   if (!A2)

     return 1;

   wchar_t *B2 = wcsdup(char16ptr_t(B));

   if (!B2) {

     free(A2);

     return 1;

   }

   int32_t result;

   wchar_t *a = A2, *b = B2;

   do {

     VersionPartW va, vb;

     a = ParseVP(a, va);

     b = ParseVP(b, vb);

     result = CompareVP(va, vb);

     if (result)

       break;

   } while (a || b);

   free(A2);

   free(B2);

   return result;

 }

 #endif

 int32_t

 CompareVersions(const char *A, const char *B)

 {

   char *A2 = strdup(A);

   if (!A2)

     return 1;

   char *B2 = strdup(B);

   if (!B2) {

     free(A2);

     return 1;

   }

   int32_t result;

   char *a = A2, *b = B2;

   do {

     VersionPart va, vb;

     a = ParseVP(a, va);

     b = ParseVP(b, vb);

     result = CompareVP(va, vb);

     if (result)

       break;

   } while (a || b);

   free(A2);

   free(B2);

   return result;

 }

 } // namespace mozilla