lib/c-strcaseeq.h

   1 /* Optimized case-insensitive string comparison in C locale.
   2    Copyright (C) 2001-2002, 2007, 2009-2014 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify it
   5    under the terms of the GNU Lesser General Public License as published
   6    by the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>.  */
  18
  19 #include "c-strcase.h"
  20 #include "c-ctype.h"
  21
  22 /* STRCASEEQ allows to optimize string comparison with a small literal string.
  23      STRCASEEQ (s, "UTF-8", 'U','T','F','-','8',0,0,0,0)
  24    is semantically equivalent to
  25      c_strcasecmp (s, "UTF-8") == 0
  26    just faster.  */
  27
  28 /* Help GCC to generate good code for string comparisons with
  29    immediate strings. */
  30 #if defined (__GNUC__) && defined (__OPTIMIZE__)
  31
  32 /* Case insensitive comparison of ASCII characters.  */
  33 # if C_CTYPE_ASCII
  34 #  define CASEEQ(other,upper) \
  35      (c_isupper (upper) ? ((other) & ~0x20) == (upper) : (other) == (upper))
  36 # elif C_CTYPE_CONSECUTIVE_UPPERCASE && C_CTYPE_CONSECUTIVE_LOWERCASE
  37 #  define CASEEQ(other,upper) \
  38      (c_isupper (upper) ? (other) == (upper) || (other) == (upper) - 'A' + 'a' : (other) == (upper))
  39 # else
  40 #  define CASEEQ(other,upper) \
  41      (c_toupper (other) == (upper))
  42 # endif
  43
  44 static inline int
  45 strcaseeq9 (const char *s1, const char *s2)
  46 {
  47   return c_strcasecmp (s1 + 9, s2 + 9) == 0;
  48 }
  49
  50 static inline int
  51 strcaseeq8 (const char *s1, const char *s2, char s28)
  52 {
  53   if (CASEEQ (s1[8], s28))
  54     {
  55       if (s28 == 0)
  56         return 1;
  57       else
  58         return strcaseeq9 (s1, s2);
  59     }
  60   else
  61     return 0;
  62 }
  63
  64 static inline int
  65 strcaseeq7 (const char *s1, const char *s2, char s27, char s28)
  66 {
  67   if (CASEEQ (s1[7], s27))
  68     {
  69       if (s27 == 0)
  70         return 1;
  71       else
  72         return strcaseeq8 (s1, s2, s28);
  73     }
  74   else
  75     return 0;
  76 }
  77
  78 static inline int
  79 strcaseeq6 (const char *s1, const char *s2, char s26, char s27, char s28)
  80 {
  81   if (CASEEQ (s1[6], s26))
  82     {
  83       if (s26 == 0)
  84         return 1;
  85       else
  86         return strcaseeq7 (s1, s2, s27, s28);
  87     }
  88   else
  89     return 0;
  90 }
  91
  92 static inline int
  93 strcaseeq5 (const char *s1, const char *s2, char s25, char s26, char s27, char s28)
  94 {
  95   if (CASEEQ (s1[5], s25))
  96     {
  97       if (s25 == 0)
  98         return 1;
  99       else
 100         return strcaseeq6 (s1, s2, s26, s27, s28);
 101     }
 102   else
 103     return 0;
 104 }
 105
 106 static inline int
 107 strcaseeq4 (const char *s1, const char *s2, char s24, char s25, char s26, char s27, char s28)
 108 {
 109   if (CASEEQ (s1[4], s24))
 110     {
 111       if (s24 == 0)
 112         return 1;
 113       else
 114         return strcaseeq5 (s1, s2, s25, s26, s27, s28);
 115     }
 116   else
 117     return 0;
 118 }
 119
 120 static inline int
 121 strcaseeq3 (const char *s1, const char *s2, char s23, char s24, char s25, char s26, char s27, char s28)
 122 {
 123   if (CASEEQ (s1[3], s23))
 124     {
 125       if (s23 == 0)
 126         return 1;
 127       else
 128         return strcaseeq4 (s1, s2, s24, s25, s26, s27, s28);
 129     }
 130   else
 131     return 0;
 132 }
 133
 134 static inline int
 135 strcaseeq2 (const char *s1, const char *s2, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
 136 {
 137   if (CASEEQ (s1[2], s22))
 138     {
 139       if (s22 == 0)
 140         return 1;
 141       else
 142         return strcaseeq3 (s1, s2, s23, s24, s25, s26, s27, s28);
 143     }
 144   else
 145     return 0;
 146 }
 147
 148 static inline int
 149 strcaseeq1 (const char *s1, const char *s2, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
 150 {
 151   if (CASEEQ (s1[1], s21))
 152     {
 153       if (s21 == 0)
 154         return 1;
 155       else
 156         return strcaseeq2 (s1, s2, s22, s23, s24, s25, s26, s27, s28);
 157     }
 158   else
 159     return 0;
 160 }
 161
 162 static inline int
 163 strcaseeq0 (const char *s1, const char *s2, char s20, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28)
 164 {
 165   if (CASEEQ (s1[0], s20))
 166     {
 167       if (s20 == 0)
 168         return 1;
 169       else
 170         return strcaseeq1 (s1, s2, s21, s22, s23, s24, s25, s26, s27, s28);
 171     }
 172   else
 173     return 0;
 174 }
 175
 176 #define STRCASEEQ(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
 177   strcaseeq0 (s1, s2, s20, s21, s22, s23, s24, s25, s26, s27, s28)
 178
 179 #else
 180
 181 #define STRCASEEQ(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \
 182   (c_strcasecmp (s1, s2) == 0)
 183
 184 #endif