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 10 * of this file, and for a DISCLAIMER OF ALL WARRANTIES. 11 * 12 * RCS: @(#) $Id: strncasecmp.c,v 1.2 1998/09/14 18:39:45 stanton Exp $ 13 */ 14 15#include "tclPort.h" 16 17/* 18 * This array is designed for mapping upper and lower case letter 19 * together for a case independent comparison. The mappings are 20 * based upon ASCII character 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 60 * in tclPort.h. 61 */ 62int strncasecmp _ANSI_ARGS_((CONST char *s1, 63 CONST char *s2, size_t n)); 64 65int strcasecmp _ANSI_ARGS_((CONST char *s1, 66 CONST char *s2)); 67 68/* 69 *---------------------------------------------------------------------- 70 * 71 * strcasecmp -- 72 * 73 * Compares two strings, ignoring case differences. 74 * 75 * Results: 76 * Compares two null-terminated strings s1 and s2, returning -1, 0, 77 * or 1 if s1 is lexicographically less than, equal to, or greater 78 * than s2. 79 * 80 * Side effects: 81 * None. 82 * 83 *---------------------------------------------------------------------- 84 */ 85 86int 87strcasecmp(s1, s2) 88 CONST char *s1; /* First string. */ 89 CONST char *s2; /* Second string. */ 90{ 91 unsigned char u1, u2; 92 93 for ( ; ; s1++, s2++) { 94 u1 = (unsigned char) *s1; 95 u2 = (unsigned char) *s2; 96 if ((u1 == '\0') || (charmap[u1] != charmap[u2])) { 97 break; 98 } 99 } 100 return charmap[u1] - charmap[u2]; 101} 102 103/* 104 *---------------------------------------------------------------------- 105 * 106 * strncasecmp -- 107 * 108 * Compares two strings, ignoring case differences. 109 * 110 * Results: 111 * Compares up to length chars of s1 and s2, returning -1, 0, or 1 112 * if s1 is lexicographically less than, equal to, or greater 113 * than s2 over those characters. 114 * 115 * Side effects: 116 * None. 117 * 118 *---------------------------------------------------------------------- 119 */ 120 121int 122strncasecmp(s1, s2, length) 123 CONST char *s1; /* First string. */ 124 CONST char *s2; /* Second string. */ 125 size_t length; /* Maximum number of characters to compare 126 * (stop earlier if the end of either string 127 * is reached). */ 128{ 129 unsigned char u1, u2; 130 131 for (; length != 0; length--, s1++, s2++) { 132 u1 = (unsigned char) *s1; 133 u2 = (unsigned char) *s2; 134 if (charmap[u1] != charmap[u2]) { 135 return charmap[u1] - charmap[u2]; 136 } 137 if (u1 == '\0') { 138 return 0; 139 } 140 } 141 return 0; 142} 143