strptime.c revision 1.18
1 /* $NetBSD: strptime.c,v 1.18 1999/04/29 02:58:30 tv Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code was contributed to The NetBSD Foundation by Klaus Klein. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the NetBSD 20 * Foundation, Inc. and its contributors. 21 * 4. Neither the name of The NetBSD Foundation nor the names of its 22 * contributors may be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <sys/cdefs.h> 39 #if defined(LIBC_SCCS) && !defined(lint) 40 __RCSID("$NetBSD: strptime.c,v 1.18 1999/04/29 02:58:30 tv Exp $"); 41 #endif 42 43 #include "namespace.h" 44 #include <sys/localedef.h> 45 #include <ctype.h> 46 #include <locale.h> 47 #include <string.h> 48 #include <time.h> 49 #include <tzfile.h> 50 51 #ifdef __weak_alias 52 __weak_alias(strptime,_strptime); 53 #endif 54 55 #define _ctloc(x) __CONCAT(_CurrentTimeLocale->,x) 56 57 /* 58 * We do not implement alternate representations. However, we always 59 * check whether a given modifier is allowed for a certain conversion. 60 */ 61 #define ALT_E 0x01 62 #define ALT_O 0x02 63 #define LEGAL_ALT(x) { if (alt_format & ~(x)) return (0); } 64 65 66 static int conv_num __P((const char **, int *, int, int)); 67 68 69 char * 70 strptime(buf, fmt, tm) 71 const char *buf, *fmt; 72 struct tm *tm; 73 { 74 char c; 75 const char *bp; 76 size_t len = 0; 77 int alt_format, i, split_year = 0; 78 79 bp = buf; 80 81 while ((c = *fmt) != '\0') { 82 /* Clear `alternate' modifier prior to new conversion. */ 83 alt_format = 0; 84 85 /* Eat up white-space. */ 86 if (isspace(c)) { 87 while (isspace(*bp)) 88 bp++; 89 90 fmt++; 91 continue; 92 } 93 94 if ((c = *fmt++) != '%') 95 goto literal; 96 97 98 again: switch (c = *fmt++) { 99 case '%': /* "%%" is converted to "%". */ 100 literal: 101 if (c != *bp++) 102 return (0); 103 break; 104 105 /* 106 * "Alternative" modifiers. Just set the appropriate flag 107 * and start over again. 108 */ 109 case 'E': /* "%E?" alternative conversion modifier. */ 110 LEGAL_ALT(0); 111 alt_format |= ALT_E; 112 goto again; 113 114 case 'O': /* "%O?" alternative conversion modifier. */ 115 LEGAL_ALT(0); 116 alt_format |= ALT_O; 117 goto again; 118 119 /* 120 * "Complex" conversion rules, implemented through recursion. 121 */ 122 case 'c': /* Date and time, using the locale's format. */ 123 LEGAL_ALT(ALT_E); 124 if (!(bp = strptime(bp, _ctloc(d_t_fmt), tm))) 125 return (0); 126 break; 127 128 case 'D': /* The date as "%m/%d/%y". */ 129 LEGAL_ALT(0); 130 if (!(bp = strptime(bp, "%m/%d/%y", tm))) 131 return (0); 132 break; 133 134 case 'R': /* The time as "%H:%M". */ 135 LEGAL_ALT(0); 136 if (!(bp = strptime(bp, "%H:%M", tm))) 137 return (0); 138 break; 139 140 case 'r': /* The time in 12-hour clock representation. */ 141 LEGAL_ALT(0); 142 if (!(bp = strptime(bp, _ctloc(t_fmt_ampm), tm))) 143 return (0); 144 break; 145 146 case 'T': /* The time as "%H:%M:%S". */ 147 LEGAL_ALT(0); 148 if (!(bp = strptime(bp, "%H:%M:%S", tm))) 149 return (0); 150 break; 151 152 case 'X': /* The time, using the locale's format. */ 153 LEGAL_ALT(ALT_E); 154 if (!(bp = strptime(bp, _ctloc(t_fmt), tm))) 155 return (0); 156 break; 157 158 case 'x': /* The date, using the locale's format. */ 159 LEGAL_ALT(ALT_E); 160 if (!(bp = strptime(bp, _ctloc(d_fmt), tm))) 161 return (0); 162 break; 163 164 /* 165 * "Elementary" conversion rules. 166 */ 167 case 'A': /* The day of week, using the locale's form. */ 168 case 'a': 169 LEGAL_ALT(0); 170 for (i = 0; i < 7; i++) { 171 /* Full name. */ 172 len = strlen(_ctloc(day[i])); 173 if (strncasecmp(_ctloc(day[i]), bp, len) == 0) 174 break; 175 176 /* Abbreviated name. */ 177 len = strlen(_ctloc(abday[i])); 178 if (strncasecmp(_ctloc(abday[i]), bp, len) == 0) 179 break; 180 } 181 182 /* Nothing matched. */ 183 if (i == 7) 184 return (0); 185 186 tm->tm_wday = i; 187 bp += len; 188 break; 189 190 case 'B': /* The month, using the locale's form. */ 191 case 'b': 192 case 'h': 193 LEGAL_ALT(0); 194 for (i = 0; i < 12; i++) { 195 /* Full name. */ 196 len = strlen(_ctloc(mon[i])); 197 if (strncasecmp(_ctloc(mon[i]), bp, len) == 0) 198 break; 199 200 /* Abbreviated name. */ 201 len = strlen(_ctloc(abmon[i])); 202 if (strncasecmp(_ctloc(abmon[i]), bp, len) == 0) 203 break; 204 } 205 206 /* Nothing matched. */ 207 if (i == 12) 208 return (0); 209 210 tm->tm_mon = i; 211 bp += len; 212 break; 213 214 case 'C': /* The century number. */ 215 LEGAL_ALT(ALT_E); 216 if (!(conv_num(&bp, &i, 0, 99))) 217 return (0); 218 219 if (split_year) { 220 tm->tm_year = (tm->tm_year % 100) + (i * 100); 221 } else { 222 tm->tm_year = i * 100; 223 split_year = 1; 224 } 225 break; 226 227 case 'd': /* The day of month. */ 228 case 'e': 229 LEGAL_ALT(ALT_O); 230 if (!(conv_num(&bp, &tm->tm_mday, 1, 31))) 231 return (0); 232 break; 233 234 case 'k': /* The hour (24-hour clock representation). */ 235 LEGAL_ALT(0); 236 /* FALLTHROUGH */ 237 case 'H': 238 LEGAL_ALT(ALT_O); 239 if (!(conv_num(&bp, &tm->tm_hour, 0, 23))) 240 return (0); 241 break; 242 243 case 'l': /* The hour (12-hour clock representation). */ 244 LEGAL_ALT(0); 245 /* FALLTHROUGH */ 246 case 'I': 247 LEGAL_ALT(ALT_O); 248 if (!(conv_num(&bp, &tm->tm_hour, 1, 12))) 249 return (0); 250 if (tm->tm_hour == 12) 251 tm->tm_hour = 0; 252 break; 253 254 case 'j': /* The day of year. */ 255 LEGAL_ALT(0); 256 if (!(conv_num(&bp, &i, 1, 366))) 257 return (0); 258 tm->tm_yday = i - 1; 259 break; 260 261 case 'M': /* The minute. */ 262 LEGAL_ALT(ALT_O); 263 if (!(conv_num(&bp, &tm->tm_min, 0, 59))) 264 return (0); 265 break; 266 267 case 'm': /* The month. */ 268 LEGAL_ALT(ALT_O); 269 if (!(conv_num(&bp, &i, 1, 12))) 270 return (0); 271 tm->tm_mon = i - 1; 272 break; 273 274 case 'p': /* The locale's equivalent of AM/PM. */ 275 LEGAL_ALT(0); 276 /* AM? */ 277 if (strcasecmp(_ctloc(am_pm[0]), bp) == 0) { 278 if (tm->tm_hour > 11) 279 return (0); 280 281 bp += strlen(_ctloc(am_pm[0])); 282 break; 283 } 284 /* PM? */ 285 else if (strcasecmp(_ctloc(am_pm[1]), bp) == 0) { 286 if (tm->tm_hour > 11) 287 return (0); 288 289 tm->tm_hour += 12; 290 bp += strlen(_ctloc(am_pm[1])); 291 break; 292 } 293 294 /* Nothing matched. */ 295 return (0); 296 297 case 'S': /* The seconds. */ 298 LEGAL_ALT(ALT_O); 299 if (!(conv_num(&bp, &tm->tm_sec, 0, 61))) 300 return (0); 301 break; 302 303 case 'U': /* The week of year, beginning on sunday. */ 304 case 'W': /* The week of year, beginning on monday. */ 305 LEGAL_ALT(ALT_O); 306 /* 307 * XXX This is bogus, as we can not assume any valid 308 * information present in the tm structure at this 309 * point to calculate a real value, so just check the 310 * range for now. 311 */ 312 if (!(conv_num(&bp, &i, 0, 53))) 313 return (0); 314 break; 315 316 case 'w': /* The day of week, beginning on sunday. */ 317 LEGAL_ALT(ALT_O); 318 if (!(conv_num(&bp, &tm->tm_wday, 0, 6))) 319 return (0); 320 break; 321 322 case 'Y': /* The year. */ 323 LEGAL_ALT(ALT_E); 324 if (!(conv_num(&bp, &i, 0, 9999))) 325 return (0); 326 327 tm->tm_year = i - TM_YEAR_BASE; 328 break; 329 330 case 'y': /* The year within 100 years of the epoch. */ 331 LEGAL_ALT(ALT_E | ALT_O); 332 if (!(conv_num(&bp, &i, 0, 99))) 333 return (0); 334 335 if (split_year) { 336 tm->tm_year = ((tm->tm_year / 100) * 100) + i; 337 break; 338 } 339 split_year = 1; 340 if (i <= 68) 341 tm->tm_year = i + 2000 - TM_YEAR_BASE; 342 else 343 tm->tm_year = i + 1900 - TM_YEAR_BASE; 344 break; 345 346 /* 347 * Miscellaneous conversions. 348 */ 349 case 'n': /* Any kind of white-space. */ 350 case 't': 351 LEGAL_ALT(0); 352 while (isspace(*bp)) 353 bp++; 354 break; 355 356 357 default: /* Unknown/unsupported conversion. */ 358 return (0); 359 } 360 361 362 } 363 364 /* LINTED functional specification */ 365 return ((char *)bp); 366 } 367 368 369 static int 370 conv_num(buf, dest, llim, ulim) 371 const char **buf; 372 int *dest; 373 int llim, ulim; 374 { 375 int result = 0; 376 377 /* The limit also determines the number of valid digits. */ 378 int rulim = ulim; 379 380 if (**buf < '0' || **buf > '9') 381 return (0); 382 383 do { 384 result *= 10; 385 result += *(*buf)++ - '0'; 386 rulim /= 10; 387 } while ((result * 10 <= ulim) && rulim && **buf >= '0' && **buf <= '9'); 388 389 if (result < llim || result > ulim) 390 return (0); 391 392 *dest = result; 393 return (1); 394 } 395
Indexes created Wed Sep 24 15:09:51 GMT 2025