lib/libalpm/rawstr.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
   9  *
  10  * This software is licensed as described in the file COPYING, which
  11  * you should have received as part of this distribution. The terms
  12  * are also available at http://curl.haxx.se/docs/copyright.html.
  13  *
  14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15  * copies of the Software, and permit persons to whom the Software is
  16  * furnished to do so, under the terms of the COPYING file.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  ***************************************************************************/
  22
  23 /* These functions are borrowed from libcurl's lib/rawstr.c with minor
  24  * modifications to style and naming. Curl_raw_equal and Curl_raw_nequal are
  25  * further modified to be true cmp style functions, returning negative, zero,
  26  * or positive. */
  27
  28 #include <stdlib.h>
  29
  30 #include "util.h"
  31
  32 /* Portable, consistent toupper (remember EBCDIC). Do not use toupper() because
  33          its behavior is altered by the current locale. */
  34 static char raw_toupper(char in)
  35 {
  36         switch(in) {
  37         case 'a':
  38                 return 'A';
  39         case 'b':
  40                 return 'B';
  41         case 'c':
  42                 return 'C';
  43         case 'd':
  44                 return 'D';
  45         case 'e':
  46                 return 'E';
  47         case 'f':
  48                 return 'F';
  49         case 'g':
  50                 return 'G';
  51         case 'h':
  52                 return 'H';
  53         case 'i':
  54                 return 'I';
  55         case 'j':
  56                 return 'J';
  57         case 'k':
  58                 return 'K';
  59         case 'l':
  60                 return 'L';
  61         case 'm':
  62                 return 'M';
  63         case 'n':
  64                 return 'N';
  65         case 'o':
  66                 return 'O';
  67         case 'p':
  68                 return 'P';
  69         case 'q':
  70                 return 'Q';
  71         case 'r':
  72                 return 'R';
  73         case 's':
  74                 return 'S';
  75         case 't':
  76                 return 'T';
  77         case 'u':
  78                 return 'U';
  79         case 'v':
  80                 return 'V';
  81         case 'w':
  82                 return 'W';
  83         case 'x':
  84                 return 'X';
  85         case 'y':
  86                 return 'Y';
  87         case 'z':
  88                 return 'Z';
  89         }
  90         return in;
  91 }
  92
  93 /*
  94  * _alpm_raw_cmp() is for doing "raw" case insensitive strings. This is meant
  95  * to be locale independent and only compare strings we know are safe for
  96  * this.  See http://daniel.haxx.se/blog/2008/10/15/strcasecmp-in-turkish/ for
  97  * some further explanation to why this function is necessary.
  98  *
  99  * The function is capable of comparing a-z case insensitively even for
 100  * non-ascii.
 101  */
 102
 103 int _alpm_raw_cmp(const char *first, const char *second)
 104 {
 105         while(*first && *second) {
 106                 if(raw_toupper(*first) != raw_toupper(*second)) {
 107                         /* get out of the loop as soon as they don't match */
 108                         break;
 109                 }
 110                 first++;
 111                 second++;
 112         }
 113         /* we do the comparison here (possibly again), just to make sure that if the
 114                  loop above is skipped because one of the strings reached zero, we must not
 115                  return this as a successful match */
 116         return (raw_toupper(*first) - raw_toupper(*second));
 117 }
 118
 119 int _alpm_raw_ncmp(const char *first, const char *second, size_t max)
 120 {
 121         while(*first && *second && max) {
 122                 if(raw_toupper(*first) != raw_toupper(*second)) {
 123                         break;
 124                 }
 125                 max--;
 126                 first++;
 127                 second++;
 128         }
 129         if(0 == max) {
 130                 /* they are equal this far */
 131                 return 0;
 132         }
 133
 134         return (raw_toupper(*first) - raw_toupper(*second));
 135 }
 136
 137 /* vim: set ts=2 sw=2 noet: */