1 /* Optimized string comparison. 2 Copyright (C) 2001-2002, 2007, 2009-2012 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 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 General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 16 17 /* Written by Bruno Haible <bruno (at) clisp.org>. */ 18 19 #ifndef _GL_STREQ_H 20 #define _GL_STREQ_H 21 22 #include <string.h> 23 24 /* STREQ_OPT allows to optimize string comparison with a small literal string. 25 STREQ_OPT (s, "EUC-KR", 'E', 'U', 'C', '-', 'K', 'R', 0, 0, 0) 26 is semantically equivalent to 27 strcmp (s, "EUC-KR") == 0 28 just faster. */ 29 30 /* Help GCC to generate good code for string comparisons with 31 immediate strings. */ 32 #if defined (__GNUC__) && defined (__OPTIMIZE__) 33 34 static inline int 35 streq9 (const char *s1, const char *s2) 36 { 37 return strcmp (s1 + 9, s2 + 9) == 0; 38 } 39 40 static inline int 41 streq8 (const char *s1, const char *s2, char s28) 42 { 43 if (s1[8] == s28) 44 { 45 if (s28 == 0) 46 return 1; 47 else 48 return streq9 (s1, s2); 49 } 50 else 51 return 0; 52 } 53 54 static inline int 55 streq7 (const char *s1, const char *s2, char s27, char s28) 56 { 57 if (s1[7] == s27) 58 { 59 if (s27 == 0) 60 return 1; 61 else 62 return streq8 (s1, s2, s28); 63 } 64 else 65 return 0; 66 } 67 68 static inline int 69 streq6 (const char *s1, const char *s2, char s26, char s27, char s28) 70 { 71 if (s1[6] == s26) 72 { 73 if (s26 == 0) 74 return 1; 75 else 76 return streq7 (s1, s2, s27, s28); 77 } 78 else 79 return 0; 80 } 81 82 static inline int 83 streq5 (const char *s1, const char *s2, char s25, char s26, char s27, char s28) 84 { 85 if (s1[5] == s25) 86 { 87 if (s25 == 0) 88 return 1; 89 else 90 return streq6 (s1, s2, s26, s27, s28); 91 } 92 else 93 return 0; 94 } 95 96 static inline int 97 streq4 (const char *s1, const char *s2, char s24, char s25, char s26, char s27, char s28) 98 { 99 if (s1[4] == s24) 100 { 101 if (s24 == 0) 102 return 1; 103 else 104 return streq5 (s1, s2, s25, s26, s27, s28); 105 } 106 else 107 return 0; 108 } 109 110 static inline int 111 streq3 (const char *s1, const char *s2, char s23, char s24, char s25, char s26, char s27, char s28) 112 { 113 if (s1[3] == s23) 114 { 115 if (s23 == 0) 116 return 1; 117 else 118 return streq4 (s1, s2, s24, s25, s26, s27, s28); 119 } 120 else 121 return 0; 122 } 123 124 static inline int 125 streq2 (const char *s1, const char *s2, char s22, char s23, char s24, char s25, char s26, char s27, char s28) 126 { 127 if (s1[2] == s22) 128 { 129 if (s22 == 0) 130 return 1; 131 else 132 return streq3 (s1, s2, s23, s24, s25, s26, s27, s28); 133 } 134 else 135 return 0; 136 } 137 138 static inline int 139 streq1 (const char *s1, const char *s2, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28) 140 { 141 if (s1[1] == s21) 142 { 143 if (s21 == 0) 144 return 1; 145 else 146 return streq2 (s1, s2, s22, s23, s24, s25, s26, s27, s28); 147 } 148 else 149 return 0; 150 } 151 152 static inline int 153 streq0 (const char *s1, const char *s2, char s20, char s21, char s22, char s23, char s24, char s25, char s26, char s27, char s28) 154 { 155 if (s1[0] == s20) 156 { 157 if (s20 == 0) 158 return 1; 159 else 160 return streq1 (s1, s2, s21, s22, s23, s24, s25, s26, s27, s28); 161 } 162 else 163 return 0; 164 } 165 166 #define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \ 167 streq0 (s1, s2, s20, s21, s22, s23, s24, s25, s26, s27, s28) 168 169 #else 170 171 #define STREQ_OPT(s1,s2,s20,s21,s22,s23,s24,s25,s26,s27,s28) \ 172 (strcmp (s1, s2) == 0) 173 174 #endif 175 176 #endif /* _GL_STREQ_H */ 177