1 /* $NetBSD: strptime.c,v 1.22 2000/12/20 20:56:34 christos 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 1.22 2000/12/20 20:56:34 christos 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) (_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 unsigned char **, int *, int, int)); 67 68 69 char * 70 strptime(buf, fmt, tm) 71 const char *buf, *fmt; 72 struct tm *tm; 73 { 74 unsigned char c; 75 const unsigned char *bp; 76 size_t len = 0; 77 int alt_format, i, split_year = 0; 78 79 bp = (const u_char *)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 = (const u_char *)strptime((const char *)bp, 125 _ctloc(d_t_fmt), tm))) 126 return (0); 127 break; 128 129 case 'D': /* The date as "%m/%d/%y". */ 130 LEGAL_ALT(0); 131 if (!(bp = (const u_char *) strptime((const char *)bp, 132 "%m/%d/%y", tm))) 133 return (0); 134 break; 135 136 case 'R': /* The time as "%H:%M". */ 137 LEGAL_ALT(0); 138 if (!(bp = (const u_char *)strptime((const char *)bp, 139 "%H:%M", tm))) 140 return (0); 141 break; 142 143 case 'r': /* The time in 12-hour clock representation. */ 144 LEGAL_ALT(0); 145 if (!(bp = (const u_char *)strptime((const char *)bp, 146 _ctloc(t_fmt_ampm), tm))) 147 return (0); 148 break; 149 150 case 'T': /* The time as "%H:%M:%S". */ 151 LEGAL_ALT(0); 152 if (!(bp = (const u_char *)strptime((const char *)bp, 153 "%H:%M:%S", tm))) 154 return (0); 155 break; 156 157 case 'X': /* The time, using the locale's format. */ 158 LEGAL_ALT(ALT_E); 159 if (!(bp = (const u_char *)strptime((const char *)bp, 160 _ctloc(t_fmt), tm))) 161 return (0); 162 break; 163 164 case 'x': /* The date, using the locale's format. */ 165 LEGAL_ALT(ALT_E); 166 if (!(bp = (const u_char *)strptime((const char *)bp, 167 _ctloc(d_fmt), tm))) 168 return (0); 169 break; 170 171 /* 172 * "Elementary" conversion rules. 173 */ 174 case 'A': /* The day of week, using the locale's form. */ 175 case 'a': 176 LEGAL_ALT(0); 177 for (i = 0; i < 7; i++) { 178 /* Full name. */ 179 len = strlen(_ctloc(day[i])); 180 if (strncasecmp(_ctloc(day[i]), 181 (const char *)bp, len) == 0) 182 break; 183 184 /* Abbreviated name. */ 185 len = strlen(_ctloc(abday[i])); 186 if (strncasecmp(_ctloc(abday[i]), 187 (const char *)bp, len) == 0) 188 break; 189 } 190 191 /* Nothing matched. */ 192 if (i == 7) 193 return (0); 194 195 tm->tm_wday = i; 196 bp += len; 197 break; 198 199 case 'B': /* The month, using the locale's form. */ 200 case 'b': 201 case 'h': 202 LEGAL_ALT(0); 203 for (i = 0; i < 12; i++) { 204 /* Full name. */ 205 len = strlen(_ctloc(mon[i])); 206 if (strncasecmp(_ctloc(mon[i]), 207 (const char *)bp, len) == 0) 208 break; 209 210 /* Abbreviated name. */ 211 len = strlen(_ctloc(abmon[i])); 212 if (strncasecmp(_ctloc(abmon[i]), 213 (const char *)bp, len) == 0) 214 break; 215 } 216 217 /* Nothing matched. */ 218 if (i == 12) 219 return (0); 220 221 tm->tm_mon = i; 222 bp += len; 223 break; 224 225 case 'C': /* The century number. */ 226 LEGAL_ALT(ALT_E); 227 if (!(conv_num(&bp, &i, 0, 99))) 228 return (0); 229 230 if (split_year) { 231 tm->tm_year = (tm->tm_year % 100) + (i * 100); 232 } else { 233 tm->tm_year = i * 100; 234 split_year = 1; 235 } 236 break; 237 238 case 'd': /* The day of month. */ 239 case 'e': 240 LEGAL_ALT(ALT_O); 241 if (!(conv_num(&bp, &tm->tm_mday, 1, 31))) 242 return (0); 243 break; 244 245 case 'k': /* The hour (24-hour clock representation). */ 246 LEGAL_ALT(0); 247 /* FALLTHROUGH */ 248 case 'H': 249 LEGAL_ALT(ALT_O); 250 if (!(conv_num(&bp, &tm->tm_hour, 0, 23))) 251 return (0); 252 break; 253 254 case 'l': /* The hour (12-hour clock representation). */ 255 LEGAL_ALT(0); 256 /* FALLTHROUGH */ 257 case 'I': 258 LEGAL_ALT(ALT_O); 259 if (!(conv_num(&bp, &tm->tm_hour, 1, 12))) 260 return (0); 261 if (tm->tm_hour == 12) 262 tm->tm_hour = 0; 263 break; 264 265 case 'j': /* The day of year. */ 266 LEGAL_ALT(0); 267 if (!(conv_num(&bp, &i, 1, 366))) 268 return (0); 269 tm->tm_yday = i - 1; 270 break; 271 272 case 'M': /* The minute. */ 273 LEGAL_ALT(ALT_O); 274 if (!(conv_num(&bp, &tm->tm_min, 0, 59))) 275 return (0); 276 break; 277 278 case 'm': /* The month. */ 279 LEGAL_ALT(ALT_O); 280 if (!(conv_num(&bp, &i, 1, 12))) 281 return (0); 282 tm->tm_mon = i - 1; 283 break; 284 285 case 'p': /* The locale's equivalent of AM/PM. */ 286 LEGAL_ALT(0); 287 /* AM? */ 288 if (strcasecmp(_ctloc(am_pm[0]), 289 (const char *)bp) == 0) { 290 if (tm->tm_hour > 11) 291 return (0); 292 293 bp += strlen(_ctloc(am_pm[0])); 294 break; 295 } 296 /* PM? */ 297 else if (strcasecmp(_ctloc(am_pm[1]), 298 (const char *)bp) == 0) { 299 if (tm->tm_hour > 11) 300 return (0); 301 302 tm->tm_hour += 12; 303 bp += strlen(_ctloc(am_pm[1])); 304 break; 305 } 306 307 /* Nothing matched. */ 308 return (0); 309 310 case 'S': /* The seconds. */ 311 LEGAL_ALT(ALT_O); 312 if (!(conv_num(&bp, &tm->tm_sec, 0, 61))) 313 return (0); 314 break; 315 316 case 'U': /* The week of year, beginning on sunday. */ 317 case 'W': /* The week of year, beginning on monday. */ 318 LEGAL_ALT(ALT_O); 319 /* 320 * XXX This is bogus, as we can not assume any valid 321 * information present in the tm structure at this 322 * point to calculate a real value, so just check the 323 * range for now. 324 */ 325 if (!(conv_num(&bp, &i, 0, 53))) 326 return (0); 327 break; 328 329 case 'w': /* The day of week, beginning on sunday. */ 330 LEGAL_ALT(ALT_O); 331 if (!(conv_num(&bp, &tm->tm_wday, 0, 6))) 332 return (0); 333 break; 334 335 case 'Y': /* The year. */ 336 LEGAL_ALT(ALT_E); 337 if (!(conv_num(&bp, &i, 0, 9999))) 338 return (0); 339 340 tm->tm_year = i - TM_YEAR_BASE; 341 break; 342 343 case 'y': /* The year within 100 years of the epoch. */ 344 LEGAL_ALT(ALT_E | ALT_O); 345 if (!(conv_num(&bp, &i, 0, 99))) 346 return (0); 347 348 if (split_year) { 349 tm->tm_year = ((tm->tm_year / 100) * 100) + i; 350 break; 351 } 352 split_year = 1; 353 if (i <= 68) 354 tm->tm_year = i + 2000 - TM_YEAR_BASE; 355 else 356 tm->tm_year = i + 1900 - TM_YEAR_BASE; 357 break; 358 359 /* 360 * Miscellaneous conversions. 361 */ 362 case 'n': /* Any kind of white-space. */ 363 case 't': 364 LEGAL_ALT(0); 365 while (isspace(*bp)) 366 bp++; 367 break; 368 369 370 default: /* Unknown/unsupported conversion. */ 371 return (0); 372 } 373 374 375 } 376 377 /* LINTED functional specification */ 378 return ((char *)bp); 379 } 380 381 382 static int 383 conv_num(buf, dest, llim, ulim) 384 const unsigned char **buf; 385 int *dest; 386 int llim, ulim; 387 { 388 int result = 0; 389 390 /* The limit also determines the number of valid digits. */ 391 int rulim = ulim; 392 393 if (**buf < '0' || **buf > '9') 394 return (0); 395 396 do { 397 result *= 10; 398 result += *(*buf)++ - '0'; 399 rulim /= 10; 400 } while ((result * 10 <= ulim) && rulim && **buf >= '0' && **buf <= '9'); 401 402 if (result < llim || result > ulim) 403 return (0); 404 405 *dest = result; 406 return (1); 407 } 408