1/* 2 * strncasecmp.c -- 3 * 4 * Source code for the "strncasecmp" library routine. 5 * 6 * Copyright (c) 1988-1993 The Regents of the University of California. 7 * Copyright (c) 1995-1996 Sun Microsystems, Inc. 8 * 9 * See the file "license.terms" for information on usage and redistribution of 10 * this file, and for a DISCLAIMER OF ALL WARRANTIES. 11 * 12 * RCS: @(#) $Id: strncasecmp.c,v 1.3 2007/04/16 13:36:34 dkf Exp $ 13 */ 14 15#include "tclPort.h" 16 17/* 18 * This array is designed for mapping upper and lower case letter together for 19 * a case independent comparison. The mappings are based upon ASCII character 20 * sequences. 21 */ 22 23static unsigned char charmap[] = { 24 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 25 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 26 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 27 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 28 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 29 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 30 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 31 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 32 0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 33 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 34 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 35 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 36 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 37 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 38 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 39 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 40 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 41 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 42 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 43 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 44 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 45 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 46 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 47 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 48 0xc0, 0xe1, 0xe2, 0xe3, 0xe4, 0xc5, 0xe6, 0xe7, 49 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 50 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 51 0xf8, 0xf9, 0xfa, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 52 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 53 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 54 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 55 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 56}; 57 58/* 59 * Here are the prototypes just in case they are not included in tclPort.h. 60 */ 61 62int strncasecmp(CONST char *s1, CONST char *s2, size_t n); 63int strcasecmp(CONST char *s1, CONST char *s2); 64 65/* 66 *---------------------------------------------------------------------- 67 * 68 * strcasecmp -- 69 * 70 * Compares two strings, ignoring case differences. 71 * 72 * Results: 73 * Compares two null-terminated strings s1 and s2, returning -1, 0, or 1 74 * if s1 is lexicographically less than, equal to, or greater than s2. 75 * 76 * Side effects: 77 * None. 78 * 79 *---------------------------------------------------------------------- 80 */ 81 82int 83strcasecmp( 84 CONST char *s1, /* First string. */ 85 CONST char *s2) /* Second string. */ 86{ 87 unsigned char u1, u2; 88 89 for ( ; ; s1++, s2++) { 90 u1 = (unsigned char) *s1; 91 u2 = (unsigned char) *s2; 92 if ((u1 == '\0') || (charmap[u1] != charmap[u2])) { 93 break; 94 } 95 } 96 return charmap[u1] - charmap[u2]; 97} 98 99/* 100 *---------------------------------------------------------------------- 101 * 102 * strncasecmp -- 103 * 104 * Compares two strings, ignoring case differences. 105 * 106 * Results: 107 * Compares up to length chars of s1 and s2, returning -1, 0, or 1 if s1 108 * is lexicographically less than, equal to, or greater than s2 over 109 * those characters. 110 * 111 * Side effects: 112 * None. 113 * 114 *---------------------------------------------------------------------- 115 */ 116 117int 118strncasecmp( 119 CONST char *s1, /* First string. */ 120 CONST char *s2, /* Second string. */ 121 size_t length) /* Maximum number of characters to compare 122 * (stop earlier if the end of either string 123 * is reached). */ 124{ 125 unsigned char u1, u2; 126 127 for (; length != 0; length--, s1++, s2++) { 128 u1 = (unsigned char) *s1; 129 u2 = (unsigned char) *s2; 130 if (charmap[u1] != charmap[u2]) { 131 return charmap[u1] - charmap[u2]; 132 } 133 if (u1 == '\0') { 134 return 0; 135 } 136 } 137 return 0; 138} 139