1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * 5 * Simple property list handling code. 6 * 7 * Copyright (c) 1998 8 * Jordan Hubbard. All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer, 15 * verbatim and that no modifications are made prior to this 16 * point in the file. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR HIS PETS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, LIFE OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/types.h> 35 #include <ctype.h> 36 #include <err.h> 37 #include <libutil.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 43 static properties 44 property_alloc(char *name, char *value) 45 { 46 properties n; 47 48 if ((n = (properties)malloc(sizeof(struct _property))) == NULL) 49 return (NULL); 50 n->next = NULL; 51 if (name != NULL) { 52 if ((n->name = strdup(name)) == NULL) { 53 free(n); 54 return (NULL); 55 } 56 } else 57 n->name = NULL; 58 if (value != NULL) { 59 if ((n->value = strdup(value)) == NULL) { 60 free(n->name); 61 free(n); 62 return (NULL); 63 } 64 } else 65 n->value = NULL; 66 return (n); 67 } 68 69 properties 70 properties_read(int fd) 71 { 72 properties head, ptr; 73 char hold_n[PROPERTY_MAX_NAME + 1]; 74 char hold_v[PROPERTY_MAX_VALUE + 1]; 75 char buf[BUFSIZ * 4]; 76 int bp, n, v, max; 77 enum { LOOK, COMMENT, NAME, VALUE, MVALUE, COMMIT, FILL, STOP } state, last_state; 78 int ch = 0, blevel = 0; 79 80 n = v = bp = max = 0; 81 head = ptr = NULL; 82 state = last_state = LOOK; 83 while (state != STOP) { 84 if (state != COMMIT) { 85 if (bp == max) { 86 last_state = state; 87 state = FILL; 88 } else 89 ch = buf[bp++]; 90 } 91 switch(state) { 92 case FILL: 93 if ((max = read(fd, buf, sizeof buf)) < 0) { 94 properties_free(head); 95 return (NULL); 96 } 97 if (max == 0) { 98 state = STOP; 99 } else { 100 /* 101 * Restore the state from before the fill (which will be 102 * initialised to LOOK for the first FILL). This ensures that 103 * if we were part-way through eg., a VALUE state, when the 104 * buffer ran out, that the previous operation will be allowed 105 * to complete. 106 */ 107 state = last_state; 108 ch = buf[0]; 109 bp = 0; 110 } 111 continue; 112 113 case LOOK: 114 if (isspace((unsigned char)ch)) 115 continue; 116 /* Allow shell or lisp style comments */ 117 else if (ch == '#' || ch == ';') { 118 state = COMMENT; 119 continue; 120 } 121 else if (isalnum((unsigned char)ch) || ch == '_') { 122 if (n >= PROPERTY_MAX_NAME) { 123 n = 0; 124 state = COMMENT; 125 } 126 else { 127 hold_n[n++] = ch; 128 state = NAME; 129 } 130 } 131 else 132 state = COMMENT; /* Ignore the rest of the line */ 133 break; 134 135 case COMMENT: 136 if (ch == '\n') 137 state = LOOK; 138 break; 139 140 case NAME: 141 if (ch == '\n' || !ch) { 142 hold_n[n] = '\0'; 143 hold_v[0] = '\0'; 144 v = n = 0; 145 state = COMMIT; 146 } 147 else if (isspace((unsigned char)ch)) 148 continue; 149 else if (ch == '=') { 150 hold_n[n] = '\0'; 151 v = n = 0; 152 state = VALUE; 153 } 154 else 155 hold_n[n++] = ch; 156 break; 157 158 case VALUE: 159 if (v == 0 && ch == '\n') { 160 hold_v[v] = '\0'; 161 v = n = 0; 162 state = COMMIT; 163 } 164 else if (v == 0 && isspace((unsigned char)ch)) 165 continue; 166 else if (ch == '{') { 167 state = MVALUE; 168 ++blevel; 169 } 170 else if (ch == '\n' || !ch) { 171 hold_v[v] = '\0'; 172 v = n = 0; 173 state = COMMIT; 174 } 175 else { 176 if (v >= PROPERTY_MAX_VALUE) { 177 state = COMMENT; 178 v = n = 0; 179 break; 180 } 181 else 182 hold_v[v++] = ch; 183 } 184 break; 185 186 case MVALUE: 187 /* multiline value */ 188 if (v >= PROPERTY_MAX_VALUE) { 189 warn("properties_read: value exceeds max length"); 190 state = COMMENT; 191 n = v = 0; 192 } 193 else if (ch == '}' && !--blevel) { 194 hold_v[v] = '\0'; 195 v = n = 0; 196 state = COMMIT; 197 } 198 else { 199 hold_v[v++] = ch; 200 if (ch == '{') 201 ++blevel; 202 } 203 break; 204 205 case COMMIT: 206 if (head == NULL) { 207 if ((head = ptr = property_alloc(hold_n, hold_v)) == NULL) 208 return (NULL); 209 } else { 210 if ((ptr->next = property_alloc(hold_n, hold_v)) == NULL) { 211 properties_free(head); 212 return (NULL); 213 } 214 ptr = ptr->next; 215 } 216 state = LOOK; 217 v = n = 0; 218 break; 219 220 case STOP: 221 /* we don't handle this here, but this prevents warnings */ 222 break; 223 } 224 } 225 if (head == NULL && (head = property_alloc(NULL, NULL)) == NULL) 226 return (NULL); 227 228 return (head); 229 } 230 231 char * 232 property_find(properties list, const char *name) 233 { 234 if (list == NULL || name == NULL || !name[0]) 235 return (NULL); 236 while (list != NULL) { 237 if (list->name != NULL && strcmp(list->name, name) == 0) 238 return (list->value); 239 list = list->next; 240 } 241 return (NULL); 242 } 243 244 void 245 properties_free(properties list) 246 { 247 properties tmp; 248 249 while (list) { 250 tmp = list->next; 251 if (list->name) 252 free(list->name); 253 if (list->value) 254 free(list->value); 255 free(list); 256 list = tmp; 257 } 258 } 259