jas_tvp.c (6925B)
1 /* 2 * Copyright (c) 2001-2002 Michael David Adams. 3 * All rights reserved. 4 */ 5 6 /* __START_OF_JASPER_LICENSE__ 7 * 8 * JasPer License Version 2.0 9 * 10 * Copyright (c) 1999-2000 Image Power, Inc. 11 * Copyright (c) 1999-2000 The University of British Columbia 12 * Copyright (c) 2001-2003 Michael David Adams 13 * 14 * All rights reserved. 15 * 16 * Permission is hereby granted, free of charge, to any person (the 17 * "User") obtaining a copy of this software and associated documentation 18 * files (the "Software"), to deal in the Software without restriction, 19 * including without limitation the rights to use, copy, modify, merge, 20 * publish, distribute, and/or sell copies of the Software, and to permit 21 * persons to whom the Software is furnished to do so, subject to the 22 * following conditions: 23 * 24 * 1. The above copyright notices and this permission notice (which 25 * includes the disclaimer below) shall be included in all copies or 26 * substantial portions of the Software. 27 * 28 * 2. The name of a copyright holder shall not be used to endorse or 29 * promote products derived from the Software without specific prior 30 * written permission. 31 * 32 * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS 33 * LICENSE. NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER 34 * THIS DISCLAIMER. THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 35 * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 36 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 37 * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN NO 38 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL 39 * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING 40 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, 41 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 42 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. NO ASSURANCES ARE 43 * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE 44 * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY. 45 * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS 46 * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL 47 * PROPERTY RIGHTS OR OTHERWISE. AS A CONDITION TO EXERCISING THE RIGHTS 48 * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE 49 * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY. THE SOFTWARE 50 * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL 51 * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES, 52 * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL 53 * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH 54 * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH, 55 * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH 56 * RISK ACTIVITIES"). THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY 57 * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES. 58 * 59 * __END_OF_JASPER_LICENSE__ 60 */ 61 62 /* 63 * Tag-Value Parser Library 64 * 65 * $Id: jas_tvp.c 1918 2005-07-24 14:12:08Z baford $ 66 */ 67 68 /******************************************************************************\ 69 * Includes. 70 \******************************************************************************/ 71 72 #include <assert.h> 73 #include <stdio.h> 74 #include <ctype.h> 75 #include <stdlib.h> 76 77 #include "jasper/jas_malloc.h" 78 #include "jasper/jas_string.h" 79 #include "jasper/jas_tvp.h" 80 81 /******************************************************************************\ 82 * Macros. 83 \******************************************************************************/ 84 85 /* Is the specified character valid for a tag name? */ 86 #define JAS_TVP_ISTAG(x) \ 87 (isalpha(x) || (x) == '_' || isdigit(x)) 88 89 /******************************************************************************\ 90 * Code for creating and destroying a tag-value parser. 91 \******************************************************************************/ 92 93 jas_tvparser_t *jas_tvparser_create(const char *s) 94 { 95 jas_tvparser_t *tvp; 96 if (!(tvp = jas_malloc(sizeof(jas_tvparser_t)))) { 97 return 0; 98 } 99 if (!(tvp->buf = jas_strdup(s))) { 100 jas_tvparser_destroy(tvp); 101 return 0; 102 } 103 tvp->pos = tvp->buf; 104 tvp->tag = 0; 105 tvp->val = 0; 106 return tvp; 107 } 108 109 void jas_tvparser_destroy(jas_tvparser_t *tvp) 110 { 111 if (tvp->buf) { 112 jas_free(tvp->buf); 113 } 114 jas_free(tvp); 115 } 116 117 /******************************************************************************\ 118 * Main parsing code. 119 \******************************************************************************/ 120 121 /* Get the next tag-value pair. */ 122 int jas_tvparser_next(jas_tvparser_t *tvp) 123 { 124 char *p; 125 char *tag; 126 char *val; 127 128 /* Skip any leading whitespace. */ 129 p = tvp->pos; 130 while (*p != '\0' && isspace(*p)) { 131 ++p; 132 } 133 134 /* Has the end of the input data been reached? */ 135 if (*p == '\0') { 136 /* No more tags are present. */ 137 tvp->pos = p; 138 return 1; 139 } 140 141 /* Does the tag name begin with a valid character? */ 142 if (!JAS_TVP_ISTAG(*p)) { 143 return -1; 144 } 145 146 /* Remember where the tag name begins. */ 147 tag = p; 148 149 /* Find the end of the tag name. */ 150 while (*p != '\0' && JAS_TVP_ISTAG(*p)) { 151 ++p; 152 } 153 154 /* Has the end of the input data been reached? */ 155 if (*p == '\0') { 156 /* The value field is empty. */ 157 tvp->tag = tag; 158 tvp->val = ""; 159 tvp->pos = p; 160 return 0; 161 } 162 163 /* Is a value field not present? */ 164 if (*p != '=') { 165 if (*p != '\0' && !isspace(*p)) { 166 return -1; 167 } 168 *p++ = '\0'; 169 tvp->tag = tag; 170 tvp->val = ""; 171 tvp->pos = p; 172 return 0; 173 } 174 175 *p++ = '\0'; 176 177 val = p; 178 while (*p != '\0' && !isspace(*p)) { 179 ++p; 180 } 181 182 if (*p != '\0') { 183 *p++ = '\0'; 184 } 185 186 tvp->pos = p; 187 tvp->tag = tag; 188 tvp->val = val; 189 190 return 0; 191 } 192 193 /******************************************************************************\ 194 * Code for querying the current tag/value. 195 \******************************************************************************/ 196 197 /* Get the current tag. */ 198 char *jas_tvparser_gettag(jas_tvparser_t *tvp) 199 { 200 return tvp->tag; 201 } 202 203 /* Get the current value. */ 204 char *jas_tvparser_getval(jas_tvparser_t *tvp) 205 { 206 return tvp->val; 207 } 208 209 /******************************************************************************\ 210 * Miscellaneous code. 211 \******************************************************************************/ 212 213 /* Lookup a tag by name. */ 214 jas_taginfo_t *jas_taginfos_lookup(jas_taginfo_t *taginfos, const char *name) 215 { 216 jas_taginfo_t *taginfo; 217 taginfo = taginfos; 218 while (taginfo->id >= 0) { 219 if (!strcmp(taginfo->name, name)) { 220 return taginfo; 221 } 222 ++taginfo; 223 } 224 return 0; 225 } 226 227 /* This function is simply for convenience. */ 228 /* One can avoid testing for the special case of a null pointer, by 229 using this function. This function never returns a null pointer. */ 230 jas_taginfo_t *jas_taginfo_nonull(jas_taginfo_t *taginfo) 231 { 232 static jas_taginfo_t invalidtaginfo = { 233 -1, 0 234 }; 235 236 return taginfo ? taginfo : &invalidtaginfo; 237 }