1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
|
/*
* strftime.c
* Original Author: G. Haley
*
* Places characters into the array pointed to by s as controlled by the string
* pointed to by format. If the total number of resulting characters including
* the terminating null character is not more than maxsize, returns the number
* of characters placed into the array pointed to by s (not including the
* terminating null character); otherwise zero is returned and the contents of
* the array indeterminate.
*/
/*
FUNCTION
<<strftime>>---flexible calendar time formatter
INDEX
strftime
ANSI_SYNOPSIS
#include <time.h>
size_t strftime(char *<[s]>, size_t <[maxsize]>,
const char *<[format]>, const struct tm *<[timp]>);
TRAD_SYNOPSIS
#include <time.h>
size_t strftime(<[s]>, <[maxsize]>, <[format]>, <[timp]>)
char *<[s]>;
size_t <[maxsize]>;
char *<[format]>;
struct tm *<[timp]>;
DESCRIPTION
<<strftime>> converts a <<struct tm>> representation of the time (at
<[timp]>) into a string, starting at <[s]> and occupying no more than
<[maxsize]> characters.
You control the format of the output using the string at <[format]>.
<<*<[format]>>> can contain two kinds of specifications: text to be
copied literally into the formatted string, and time conversion
specifications. Time conversion specifications are two-character
sequences beginning with `<<%>>' (use `<<%%>>' to include a percent
sign in the output). Each defined conversion specification selects a
field of calendar time data from <<*<[timp]>>>, and converts it to a
string in one of the following ways:
o+
o %a
An abbreviation for the day of the week.
o %A
The full name for the day of the week.
o %b
An abbreviation for the month name.
o %B
The full name of the month.
o %c
A string representing the complete date and time, in the form
. Mon Apr 01 13:13:13 1992
o %d
The day of the month, formatted with two digits.
o %e
The day of the month, formatted with leading space if single digit.
o %H
The hour (on a 24-hour clock), formatted with two digits.
o %I
The hour (on a 12-hour clock), formatted with two digits.
o %j
The count of days in the year, formatted with three digits
(from `<<001>>' to `<<366>>').
o %m
The month number, formatted with two digits.
o %M
The minute, formatted with two digits.
o %p
Either `<<AM>>' or `<<PM>>' as appropriate.
o %r
Equivalent to "%I:%M:%S %p".
o %S
The second, formatted with two digits.
o %U
The week number, formatted with two digits (from `<<00>>' to `<<53>>';
week number 1 is taken as beginning with the first Sunday in a year).
See also <<%W>>.
o %w
A single digit representing the day of the week: Sunday is day <<0>>.
o %W
Another version of the week number: like `<<%U>>', but counting week 1
as beginning with the first Monday in a year.
o
o %x
A string representing the complete date, equivalent to "%m/%d/%y".
o %X
A string representing the full time of day (hours, minutes, and
seconds), equivalent to "%T".
o %y
The last two digits of the year.
o %Y
The full year, formatted with four digits to include the century.
o %Z
The time zone name. If tm_isdst is -1, no output is generated.
Otherwise, the time zone name based on the TZ environment variable
is used.
o %%
A single character, `<<%>>'.
o-
RETURNS
When the formatted time takes up no more than <[maxsize]> characters,
the result is the length of the formatted string. Otherwise, if the
formatting operation was abandoned due to lack of room, the result is
<<0>>, and the string starting at <[s]> corresponds to just those
parts of <<*<[format]>>> that could be completely filled in within the
<[maxsize]> limit.
PORTABILITY
ANSI C requires <<strftime>>, but does not specify the contents of
<<*<[s]>>> when the formatted string would require more than
<[maxsize]> characters.
<<strftime>> requires no supporting OS subroutines.
*/
#include <stddef.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include "local.h"
static _CONST int dname_len[7] =
{6, 6, 7, 9, 8, 6, 8};
static _CONST char *_CONST dname[7] =
{"Sunday", "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday"};
static _CONST int mname_len[12] =
{7, 8, 5, 5, 3, 4, 4, 6, 9, 7, 8, 8};
static _CONST char *_CONST mname[12] =
{"January", "February", "March", "April",
"May", "June", "July", "August", "September", "October", "November",
"December"};
size_t
_DEFUN (strftime, (s, maxsize, format, tim_p),
char *s _AND
size_t maxsize _AND
_CONST char *format _AND
_CONST struct tm *tim_p)
{
size_t count = 0;
int i;
for (;;)
{
while (*format && *format != '%')
{
if (count < maxsize - 1)
s[count++] = *format++;
else
return 0;
}
if (*format == '\0')
break;
format++;
check_format:
switch (*format)
{
case 'a':
for (i = 0; i < 3; i++)
{
if (count < maxsize - 1)
s[count++] =
dname[tim_p->tm_wday][i];
else
return 0;
}
break;
case 'A':
for (i = 0; i < dname_len[tim_p->tm_wday]; i++)
{
if (count < maxsize - 1)
s[count++] =
dname[tim_p->tm_wday][i];
else
return 0;
}
break;
case 'b':
case 'h':
for (i = 0; i < 3; i++)
{
if (count < maxsize - 1)
s[count++] =
mname[tim_p->tm_mon][i];
else
return 0;
}
break;
case 'B':
for (i = 0; i < mname_len[tim_p->tm_mon]; i++)
{
if (count < maxsize - 1)
s[count++] =
mname[tim_p->tm_mon][i];
else
return 0;
}
break;
case 'c':
if (count < maxsize - 24)
{
for (i = 0; i < 3; i++)
s[count++] =
dname[tim_p->tm_wday][i];
s[count++] = ' ';
for (i = 0; i < 3; i++)
s[count++] =
mname[tim_p->tm_mon][i];
sprintf (&s[count],
" %.2d %2.2d:%2.2d:%2.2d %.4d",
tim_p->tm_mday, tim_p->tm_hour,
tim_p->tm_min,
tim_p->tm_sec, 1900 +
tim_p->tm_year);
count += 17;
}
else
return 0;
break;
case 'd':
if (count < maxsize - 2)
{
sprintf (&s[count], "%.2d",
tim_p->tm_mday);
count += 2;
}
else
return 0;
break;
case 'E':
++format;
switch (*format)
{
case 'c':
case 'C':
case 'x':
case 'X':
case 'y':
case 'Y':
/* Ignore. */
goto check_format;
default:
--format;
}
break;
case 'e':
if (count < maxsize - 2)
{
sprintf (&s[count], "%2d",
tim_p->tm_mday);
count += 2;
}
else
return 0;
break;
case 'H':
case 'k':
if (count < maxsize - 2)
{
sprintf (&s[count], *format == 'k' ? "%2d" : "%2.2d",
tim_p->tm_hour);
count += 2;
}
else
return 0;
break;
case 'I':
case 'l':
if (count < maxsize - 2)
{
if (tim_p->tm_hour == 0 ||
tim_p->tm_hour == 12)
{
s[count++] = '1';
s[count++] = '2';
}
else
{
sprintf (&s[count], (*format == 'I') ? "%.2d" : "%2d",
tim_p->tm_hour % 12);
count += 2;
}
}
else
return 0;
break;
case 'j':
if (count < maxsize - 3)
{
sprintf (&s[count], "%.3d",
tim_p->tm_yday + 1);
count += 3;
}
else
return 0;
break;
case 'm':
if (count < maxsize - 2)
{
sprintf (&s[count], "%.2d",
tim_p->tm_mon + 1);
count += 2;
}
else
return 0;
break;
case 'M':
if (count < maxsize - 2)
{
sprintf (&s[count], "%2.2d",
tim_p->tm_min);
count += 2;
}
else
return 0;
break;
case 'O':
++format;
switch (*format)
{
case 'd':
case 'e':
case 'H':
case 'I':
case 'm':
case 'M':
case 'S':
case 'u':
case 'U':
case 'V':
case 'w':
case 'W':
case 'y':
/* Ignore. */
goto check_format;
default:
--format;
}
break;
case 'p':
if (count < maxsize - 2)
{
if (tim_p->tm_hour < 12)
s[count++] = 'A';
else
s[count++] = 'P';
s[count++] = 'M';
}
else
return 0;
break;
case 'r':
if (count < maxsize - 11)
{
if (tim_p->tm_hour == 0 ||
tim_p->tm_hour == 12)
{
s[count++] = '1';
s[count++] = '2';
}
else
{
sprintf (&s[count], "%.2d", tim_p->tm_hour % 12);
count += 2;
}
s[count++] = ':';
sprintf (&s[count], "%2.2d",
tim_p->tm_min);
count += 2;
s[count++] = ':';
sprintf (&s[count], "%2.2d",
tim_p->tm_sec);
count += 2;
s[count++] = ' ';
if (tim_p->tm_hour < 12)
s[count++] = 'A';
else
s[count++] = 'P';
s[count++] = 'M';
}
else
return 0;
break;
case 'S':
if (count < maxsize - 2)
{
sprintf (&s[count], "%2.2d",
tim_p->tm_sec);
count += 2;
}
else
return 0;
break;
case 'U':
if (count < maxsize - 2)
{
sprintf (&s[count], "%2.2d",
(tim_p->tm_yday + 7 -
tim_p->tm_wday) / 7);
count += 2;
}
else
return 0;
break;
case 'w':
if (count < maxsize - 1)
{
sprintf (&s[count], "%1.1d",
tim_p->tm_wday);
count++;
}
else
return 0;
break;
case 'W':
if (count < maxsize - 2)
{
int wday = (tim_p->tm_wday) ? tim_p->tm_wday - 1 : 6;
sprintf (&s[count], "%2.2d",
(tim_p->tm_yday + 7 -
wday) / 7);
count += 2;
}
else
return 0;
break;
case 'x':
if (count < maxsize - 8)
{
sprintf (&s[count], "%.2d",
tim_p->tm_mon + 1);
count += 2;
s[count++] = '/';
sprintf (&s[count], "%.2d",
tim_p->tm_mday);
count += 2;
s[count++] = '/';
/* The year could be greater than 100, so we need the value
modulo 100. The year could be negative, so we need to
correct for a possible negative remainder. */
sprintf (&s[count], "%2.2d",
(tim_p->tm_year % 100 + 100) % 100);
count += 2;
}
else
return 0;
break;
case 'X':
if (count < maxsize - 8)
{
sprintf (&s[count],
"%2.2d:%2.2d:%2.2d",
tim_p->tm_hour, tim_p->tm_min,
tim_p->tm_sec);
count += 8;
}
else
return 0;
break;
case 'y':
if (count < maxsize - 2)
{
/* The year could be greater than 100, so we need the value
modulo 100. The year could be negative, so we need to
correct for a possible negative remainder. */
sprintf (&s[count], "%2.2d",
(tim_p->tm_year % 100 + 100) % 100);
count += 2;
}
else
return 0;
break;
case 'Y':
if (count < maxsize - 4)
{
sprintf (&s[count], "%.4d",
1900 + tim_p->tm_year);
count += 4;
}
else
return 0;
break;
case 'Z':
if (tim_p->tm_isdst >= 0)
{
int size;
TZ_LOCK;
size = strlen(_tzname[tim_p->tm_isdst]);
for (i = 0; i < size; i++)
{
if (count < maxsize - 1)
s[count++] = _tzname[tim_p->tm_isdst][i];
else
{
TZ_UNLOCK;
return 0;
}
}
TZ_UNLOCK;
}
break;
case '%':
if (count < maxsize - 1)
s[count++] = '%';
else
return 0;
break;
}
if (*format)
format++;
else
break;
}
s[count] = '\0';
return count;
}
|