1 /* tdate_parse - parse string dates into internal form, stripped-down version
2 **
3 ** Copyright (C) 1995 by Jef Poskanzer <[email protected]>. All rights reserved.
4 **
5 ** Redistribution and use in source and binary forms, with or without
6 ** modification, are permitted provided that the following conditions
7 ** are met:
8 ** 1. Redistributions of source code must retain the above copyright
9 ** notice, this list of conditions and the following disclaimer.
10 ** 2. Redistributions in binary form must reproduce the above copyright
11 ** notice, this list of conditions and the following disclaimer in the
12 ** documentation and/or other materials provided with the distribution.
13 **
14 ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 ** ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 ** SUCH DAMAGE.
25 */
26
27 /* This is a stripped-down version of date_parse.c, available at
28 ** http://www.acme.com/software/date_parse/
29 */
30
31 #include <sys/types.h>
32
33 #include <ctype.h>
34 #ifdef HAVE_MEMORY_H
35 #include <memory.h>
36 #endif
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <time.h>
41
42 #include "tdate_parse.h"
43
44
45 struct strlong {
46 char* s;
47 long l;
48 };
49
50
51 static void
pound_case(char * str)52 pound_case( char* str )
53 {
54 for ( ; *str != '\0'; ++str )
55 {
56 if ( isupper( *str ) )
57 *str = tolower( *str );
58 }
59 }
60
61 static int
strlong_compare(v1,v2)62 strlong_compare( v1, v2 )
63 char* v1;
64 char* v2;
65 {
66 return strcmp( ((struct strlong*) v1)->s, ((struct strlong*) v2)->s );
67 }
68
69
70 static int
strlong_search(char * str,struct strlong * tab,int n,long * lP)71 strlong_search( char* str, struct strlong* tab, int n, long* lP )
72 {
73 int i, h, l, r;
74
75 l = 0;
76 h = n - 1;
77 for (;;)
78 {
79 i = ( h + l ) / 2;
80 r = strcmp( str, tab[i].s );
81 if ( r < 0 )
82 h = i - 1;
83 else if ( r > 0 )
84 l = i + 1;
85 else
86 {
87 *lP = tab[i].l;
88 return 1;
89 }
90 if ( h < l )
91 return 0;
92 }
93 }
94
95
96 static int
scan_wday(char * str_wday,long * tm_wdayP)97 scan_wday( char* str_wday, long* tm_wdayP )
98 {
99 static struct strlong wday_tab[] = {
100 { "sun", 0 }, { "sunday", 0 },
101 { "mon", 1 }, { "monday", 1 },
102 { "tue", 2 }, { "tuesday", 2 },
103 { "wed", 3 }, { "wednesday", 3 },
104 { "thu", 4 }, { "thursday", 4 },
105 { "fri", 5 }, { "friday", 5 },
106 { "sat", 6 }, { "saturday", 6 },
107 };
108 static int sorted = 0;
109
110 if ( ! sorted )
111 {
112 (void) qsort(
113 wday_tab, sizeof(wday_tab)/sizeof(struct strlong),
114 sizeof(struct strlong), strlong_compare );
115 sorted = 1;
116 }
117 pound_case( str_wday );
118 return strlong_search(
119 str_wday, wday_tab, sizeof(wday_tab)/sizeof(struct strlong), tm_wdayP );
120 }
121
122
123 static int
scan_mon(char * str_mon,long * tm_monP)124 scan_mon( char* str_mon, long* tm_monP )
125 {
126 static struct strlong mon_tab[] = {
127 { "jan", 0 }, { "january", 0 },
128 { "feb", 1 }, { "february", 1 },
129 { "mar", 2 }, { "march", 2 },
130 { "apr", 3 }, { "april", 3 },
131 { "may", 4 },
132 { "jun", 5 }, { "june", 5 },
133 { "jul", 6 }, { "july", 6 },
134 { "aug", 7 }, { "august", 7 },
135 { "sep", 8 }, { "september", 8 },
136 { "oct", 9 }, { "october", 9 },
137 { "nov", 10 }, { "november", 10 },
138 { "dec", 11 }, { "december", 11 },
139 };
140 static int sorted = 0;
141
142 if ( ! sorted )
143 {
144 (void) qsort(
145 mon_tab, sizeof(mon_tab)/sizeof(struct strlong),
146 sizeof(struct strlong), strlong_compare );
147 sorted = 1;
148 }
149 pound_case( str_mon );
150 return strlong_search(
151 str_mon, mon_tab, sizeof(mon_tab)/sizeof(struct strlong), tm_monP );
152 }
153
154
155 static int
is_leap(int year)156 is_leap( int year )
157 {
158 return year % 400? ( year % 100 ? ( year % 4 ? 0 : 1 ) : 0 ) : 1;
159 }
160
161
162 /* Basically the same as mktime(). */
163 static time_t
tm_to_time(struct tm * tmP)164 tm_to_time( struct tm* tmP )
165 {
166 time_t t;
167 static int monthtab[12] = {
168 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
169
170 /* Years since epoch, converted to days. */
171 t = ( tmP->tm_year - 70 ) * 365;
172 /* Leap days for previous years. */
173 t += ( tmP->tm_year - 1 - 68 ) / 4; /* -1: don't count this year */
174 /* 100-divisible year is not a leap year
175 400-divisible year is a leap year */
176 if (tmP->tm_year > 200)
177 t -= (tmP->tm_year - 1 - 100) / 100;
178 if (tmP->tm_year > 500)
179 t += (tmP->tm_year - 1 - 100) / 400;
180
181 /* Days for the beginning of this month. */
182 t += monthtab[tmP->tm_mon];
183 /* Leap day for this year. */
184 if ( tmP->tm_mon >= 2 && is_leap( tmP->tm_year ) )
185 ++t;
186 /* Days since the beginning of this month. */
187 t += tmP->tm_mday - 1; /* 1-based field */
188 /* Hours, minutes, and seconds. */
189 t = t * 24 + tmP->tm_hour;
190 t = t * 60 + tmP->tm_min;
191 t = t * 60 + tmP->tm_sec;
192
193 return t;
194 }
195
196
197 time_t
httpdate_to_timet(const char * str)198 httpdate_to_timet( const char* str )
199 {
200 struct tm tm;
201 const char* cp;
202 char str_mon[500], str_wday[500];
203 int tm_sec, tm_min, tm_hour, tm_mday, tm_year;
204 long tm_mon, tm_wday;
205 time_t t;
206
207 /* Initialize. */
208 memset( (char*) &tm, 0, sizeof(struct tm) );
209
210 /* Skip initial whitespace ourselves - sscanf is clumsy at this. */
211 for ( cp = str; *cp == ' ' || *cp == '\t'; ++cp )
212 ;
213
214 /* And do the sscanfs. WARNING: you can add more formats here,
215 ** but be careful! You can easily screw up the parsing of existing
216 ** formats when you add new ones. The order is important.
217 */
218
219 /* DD-mth-YY HH:MM:SS GMT */
220 if ( sscanf( cp, "%d-%[a-zA-Z]-%d %d:%d:%d GMT",
221 &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
222 &tm_sec ) == 6 &&
223 scan_mon( str_mon, &tm_mon ) )
224 {
225 tm.tm_mday = tm_mday;
226 tm.tm_mon = tm_mon;
227 tm.tm_year = tm_year;
228 tm.tm_hour = tm_hour;
229 tm.tm_min = tm_min;
230 tm.tm_sec = tm_sec;
231 }
232
233 /* DD mth YY HH:MM:SS GMT */
234 else if ( sscanf( cp, "%d %[a-zA-Z] %d %d:%d:%d GMT",
235 &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
236 &tm_sec) == 6 &&
237 scan_mon( str_mon, &tm_mon ) )
238 {
239 tm.tm_mday = tm_mday;
240 tm.tm_mon = tm_mon;
241 tm.tm_year = tm_year;
242 tm.tm_hour = tm_hour;
243 tm.tm_min = tm_min;
244 tm.tm_sec = tm_sec;
245 }
246
247 /* HH:MM:SS GMT DD-mth-YY */
248 else if ( sscanf( cp, "%d:%d:%d GMT %d-%[a-zA-Z]-%d",
249 &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon,
250 &tm_year ) == 6 &&
251 scan_mon( str_mon, &tm_mon ) )
252 {
253 tm.tm_hour = tm_hour;
254 tm.tm_min = tm_min;
255 tm.tm_sec = tm_sec;
256 tm.tm_mday = tm_mday;
257 tm.tm_mon = tm_mon;
258 tm.tm_year = tm_year;
259 }
260
261 /* HH:MM:SS GMT DD mth YY */
262 else if ( sscanf( cp, "%d:%d:%d GMT %d %[a-zA-Z] %d",
263 &tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon,
264 &tm_year ) == 6 &&
265 scan_mon( str_mon, &tm_mon ) )
266 {
267 tm.tm_hour = tm_hour;
268 tm.tm_min = tm_min;
269 tm.tm_sec = tm_sec;
270 tm.tm_mday = tm_mday;
271 tm.tm_mon = tm_mon;
272 tm.tm_year = tm_year;
273 }
274
275 /* wdy, DD-mth-YY HH:MM:SS GMT */
276 else if ( sscanf( cp, "%[a-zA-Z], %d-%[a-zA-Z]-%d %d:%d:%d GMT",
277 str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
278 &tm_sec ) == 7 &&
279 scan_wday( str_wday, &tm_wday ) &&
280 scan_mon( str_mon, &tm_mon ) )
281 {
282 tm.tm_wday = tm_wday;
283 tm.tm_mday = tm_mday;
284 tm.tm_mon = tm_mon;
285 tm.tm_year = tm_year;
286 tm.tm_hour = tm_hour;
287 tm.tm_min = tm_min;
288 tm.tm_sec = tm_sec;
289 }
290
291 /* wdy, DD mth YY HH:MM:SS GMT */
292 else if ( sscanf( cp, "%[a-zA-Z], %d %[a-zA-Z] %d %d:%d:%d GMT",
293 str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
294 &tm_sec ) == 7 &&
295 scan_wday( str_wday, &tm_wday ) &&
296 scan_mon( str_mon, &tm_mon ) )
297 {
298 tm.tm_wday = tm_wday;
299 tm.tm_mday = tm_mday;
300 tm.tm_mon = tm_mon;
301 tm.tm_year = tm_year;
302 tm.tm_hour = tm_hour;
303 tm.tm_min = tm_min;
304 tm.tm_sec = tm_sec;
305 }
306
307 /* wdy mth DD HH:MM:SS GMT YY */
308 else if ( sscanf( cp, "%[a-zA-Z] %[a-zA-Z] %d %d:%d:%d GMT %d",
309 str_wday, str_mon, &tm_mday, &tm_hour, &tm_min, &tm_sec,
310 &tm_year ) == 7 &&
311 scan_wday( str_wday, &tm_wday ) &&
312 scan_mon( str_mon, &tm_mon ) )
313 {
314 tm.tm_wday = tm_wday;
315 tm.tm_mon = tm_mon;
316 tm.tm_mday = tm_mday;
317 tm.tm_hour = tm_hour;
318 tm.tm_min = tm_min;
319 tm.tm_sec = tm_sec;
320 tm.tm_year = tm_year;
321 }
322 else
323 return (time_t) -1;
324
325 if ( tm.tm_year > 1900 )
326 tm.tm_year -= 1900;
327 else if ( tm.tm_year < 70 )
328 tm.tm_year += 100;
329
330 t = tm_to_time( &tm );
331
332 return t;
333 }
334
335 /*
336 Convert 't' (in time_t format) into the HTTP date format
337 <input parameters>
338 t: input (epoch-based time)
339 str: output string that holds the HTTP date strinng
340 strlen: the buffer size of str
341
342 <return value>
343 0 : in case of successful conversion
344 -1 : otherwise
345 by KyoungSoo Park
346 */
347 int
timet_to_httpdate(time_t t,char * str,int strlen)348 timet_to_httpdate(time_t t, char* str, int strlen )
349 {
350 static const char* day_of_week[] = {"Sun", "Mon","Tue",
351 "Wed", "Thu", "Fri", "Sat"};
352
353 static const char* months[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
354 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
355 struct tm gm;
356
357 if (gmtime_r(&t, &gm) == NULL)
358 return(-1);
359
360 /* example date: "Sat, 26 Mar 2011 05:53:57 GMT" */
361 if (snprintf(str, strlen,
362 "%s, %02d %s %4d %02d:%02d:%02d GMT",
363 day_of_week[gm.tm_wday],
364 gm.tm_mday,
365 months[gm.tm_mon],
366 gm.tm_year + 1900,
367 gm.tm_hour,
368 gm.tm_min,
369 gm.tm_sec) == strlen)
370 /* probably str has an insufficient buffer size */
371 return (-1);
372 return(0);
373 }
374