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      1 /*************************************************
      2 *      Perl-Compatible Regular Expressions       *
      3 *************************************************/
      4 
      5 /* PCRE is a library of functions to support regular expressions whose syntax
      6 and semantics are as close as possible to those of the Perl 5 language.
      7 
      8                        Written by Philip Hazel
      9      Original API code Copyright (c) 1997-2012 University of Cambridge
     10          New API code Copyright (c) 2016 University of Cambridge
     11 
     12 -----------------------------------------------------------------------------
     13 Redistribution and use in source and binary forms, with or without
     14 modification, are permitted provided that the following conditions are met:
     15 
     16     * Redistributions of source code must retain the above copyright notice,
     17       this list of conditions and the following disclaimer.
     18 
     19     * Redistributions in binary form must reproduce the above copyright
     20       notice, this list of conditions and the following disclaimer in the
     21       documentation and/or other materials provided with the distribution.
     22 
     23     * Neither the name of the University of Cambridge nor the names of its
     24       contributors may be used to endorse or promote products derived from
     25       this software without specific prior written permission.
     26 
     27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
     28 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     29 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     30 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
     31 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37 POSSIBILITY OF SUCH DAMAGE.
     38 -----------------------------------------------------------------------------
     39 */
     40 
     41 /* This module contains internal functions for comparing and finding the length
     42 of strings. These are used instead of strcmp() etc because the standard
     43 functions work only on 8-bit data. */
     44 
     45 
     46 #ifdef HAVE_CONFIG_H
     47 #include "config.h"
     48 #endif
     49 
     50 #include "pcre2_internal.h"
     51 
     52 
     53 /*************************************************
     54 *    Compare two zero-terminated PCRE2 strings   *
     55 *************************************************/
     56 
     57 /*
     58 Arguments:
     59   str1        first string
     60   str2        second string
     61 
     62 Returns:      0, 1, or -1
     63 */
     64 
     65 int
     66 PRIV(strcmp)(PCRE2_SPTR str1, PCRE2_SPTR str2)
     67 {
     68 PCRE2_UCHAR c1, c2;
     69 while (*str1 != '\0' || *str2 != '\0')
     70   {
     71   c1 = *str1++;
     72   c2 = *str2++;
     73   if (c1 != c2) return ((c1 > c2) << 1) - 1;
     74   }
     75 return 0;
     76 }
     77 
     78 
     79 /*************************************************
     80 *  Compare zero-terminated PCRE2 & 8-bit strings *
     81 *************************************************/
     82 
     83 /* As the 8-bit string is almost always a literal, its type is specified as
     84 const char *.
     85 
     86 Arguments:
     87   str1        first string
     88   str2        second string
     89 
     90 Returns:      0, 1, or -1
     91 */
     92 
     93 int
     94 PRIV(strcmp_c8)(PCRE2_SPTR str1, const char *str2)
     95 {
     96 PCRE2_UCHAR c1, c2;
     97 while (*str1 != '\0' || *str2 != '\0')
     98   {
     99   c1 = *str1++;
    100   c2 = *str2++;
    101   if (c1 != c2) return ((c1 > c2) << 1) - 1;
    102   }
    103 return 0;
    104 }
    105 
    106 
    107 /*************************************************
    108 *    Compare two PCRE2 strings, given a length   *
    109 *************************************************/
    110 
    111 /*
    112 Arguments:
    113   str1        first string
    114   str2        second string
    115   len         the length
    116 
    117 Returns:      0, 1, or -1
    118 */
    119 
    120 int
    121 PRIV(strncmp)(PCRE2_SPTR str1, PCRE2_SPTR str2, size_t len)
    122 {
    123 PCRE2_UCHAR c1, c2;
    124 for (; len > 0; len--)
    125   {
    126   c1 = *str1++;
    127   c2 = *str2++;
    128   if (c1 != c2) return ((c1 > c2) << 1) - 1;
    129   }
    130 return 0;
    131 }
    132 
    133 
    134 /*************************************************
    135 * Compare PCRE2 string to 8-bit string by length *
    136 *************************************************/
    137 
    138 /* As the 8-bit string is almost always a literal, its type is specified as
    139 const char *.
    140 
    141 Arguments:
    142   str1        first string
    143   str2        second string
    144   len         the length
    145 
    146 Returns:      0, 1, or -1
    147 */
    148 
    149 int
    150 PRIV(strncmp_c8)(PCRE2_SPTR str1, const char *str2, size_t len)
    151 {
    152 PCRE2_UCHAR c1, c2;
    153 for (; len > 0; len--)
    154   {
    155   c1 = *str1++;
    156   c2 = *str2++;
    157   if (c1 != c2) return ((c1 > c2) << 1) - 1;
    158   }
    159 return 0;
    160 }
    161 
    162 
    163 /*************************************************
    164 *        Find the length of a PCRE2 string       *
    165 *************************************************/
    166 
    167 /*
    168 Argument:    the string
    169 Returns:     the length
    170 */
    171 
    172 PCRE2_SIZE
    173 PRIV(strlen)(PCRE2_SPTR str)
    174 {
    175 PCRE2_SIZE c = 0;
    176 while (*str++ != 0) c++;
    177 return c;
    178 }
    179 
    180 
    181 /*************************************************
    182 * Copy 8-bit 0-terminated string to PCRE2 string *
    183 *************************************************/
    184 
    185 /* Arguments:
    186   str1     buffer to receive the string
    187   str2     8-bit string to be copied
    188 
    189 Returns:   the number of code units used (excluding trailing zero)
    190 */
    191 
    192 PCRE2_SIZE
    193 PRIV(strcpy_c8)(PCRE2_UCHAR *str1, const char *str2)
    194 {
    195 PCRE2_UCHAR *t = str1;
    196 while (*str2 != 0) *t++ = *str2++;
    197 *t = 0;
    198 return t - str1;
    199 }
    200 
    201 /* End of pcre2_string_utils.c */
    202