1 /* vsprintf with automatic memory allocation.
2 Copyright (C) 1999, 2002-2005 Free Software Foundation, Inc.
3
4 This program is free software; you can redistribute it and/or modify it
5 under the terms of the GNU Library General Public License as published
6 by the Free Software Foundation; either version 2, or (at your option)
7 any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
13
14 You should have received a copy of the GNU Library General Public
15 License along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17 USA. */
18
19 /* Tell glibc's <stdio.h> to provide a prototype for snprintf().
20 This must come before <config.h> because <config.h> may include
21 <features.h>, and once <features.h> has been included, it's too late. */
22 #ifndef _GNU_SOURCE
23 # define _GNU_SOURCE 1
24 #endif
25
26 #ifdef HAVE_CONFIG_H
27 # include <config.h>
28 #endif
29 #ifndef IN_LIBINTL
30 # include <alloca.h>
31 #endif
32
33 /* Specification. */
34 #if WIDE_CHAR_VERSION
35 # include "vasnwprintf.h"
36 #else
37 # include "vasnprintf.h"
38 #endif
39
40 #include <stdio.h> /* snprintf(), sprintf() */
41 #include <stdlib.h> /* abort(), malloc(), realloc(), free() */
42 #include <string.h> /* memcpy(), strlen() */
43 #include <errno.h> /* errno */
44 #include <limits.h> /* CHAR_BIT, INT_MAX */
45 #include <float.h> /* DBL_MAX_EXP, LDBL_MAX_EXP */
46 #if WIDE_CHAR_VERSION
47 # include "wprintf-parse.h"
48 #else
49 # include "printf-parse.h"
50 #endif
51
52 /* Checked size_t computations. */
53 #include "xsize.h"
54
55 /* Some systems, like OSF/1 4.0 and Woe32, don't have EOVERFLOW. */
56 #ifndef EOVERFLOW
57 # define EOVERFLOW E2BIG
58 #endif
59
60 #ifdef HAVE_WCHAR_T
61 # ifdef HAVE_WCSLEN
62 # define local_wcslen wcslen
63 # else
64 /* Solaris 2.5.1 has wcslen() in a separate library libw.so. To avoid
65 a dependency towards this library, here is a local substitute.
66 Define this substitute only once, even if this file is included
67 twice in the same compilation unit. */
68 # ifndef local_wcslen_defined
69 # define local_wcslen_defined 1
70 static size_t
local_wcslen(const wchar_t * s)71 local_wcslen (const wchar_t *s)
72 {
73 const wchar_t *ptr;
74
75 for (ptr = s; *ptr != (wchar_t) 0; ptr++)
76 ;
77 return ptr - s;
78 }
79 # endif
80 # endif
81 #endif
82
83 #if WIDE_CHAR_VERSION
84 # define VASNPRINTF vasnwprintf
85 # define CHAR_T wchar_t
86 # define DIRECTIVE wchar_t_directive
87 # define DIRECTIVES wchar_t_directives
88 # define PRINTF_PARSE wprintf_parse
89 # define USE_SNPRINTF 1
90 # if HAVE_DECL__SNWPRINTF
91 /* On Windows, the function swprintf() has a different signature than
92 on Unix; we use the _snwprintf() function instead. */
93 # define SNPRINTF _snwprintf
94 # else
95 /* Unix. */
96 # define SNPRINTF swprintf
97 # endif
98 #else
99 # define VASNPRINTF vasnprintf
100 # define CHAR_T char
101 # define DIRECTIVE char_directive
102 # define DIRECTIVES char_directives
103 # define PRINTF_PARSE printf_parse
104 # define USE_SNPRINTF (HAVE_DECL__SNPRINTF || HAVE_SNPRINTF)
105 # if HAVE_DECL__SNPRINTF
106 /* Windows. */
107 # define SNPRINTF _snprintf
108 # else
109 /* Unix. */
110 # define SNPRINTF snprintf
111 # endif
112 #endif
113
114 CHAR_T *
VASNPRINTF(CHAR_T * resultbuf,size_t * lengthp,const CHAR_T * format,va_list args)115 VASNPRINTF (CHAR_T *resultbuf, size_t *lengthp, const CHAR_T *format, va_list args)
116 {
117 DIRECTIVES d;
118 arguments a;
119
120 if (PRINTF_PARSE (format, &d, &a) < 0)
121 {
122 errno = EINVAL;
123 return NULL;
124 }
125
126 #define CLEANUP() \
127 free (d.dir); \
128 if (a.arg) \
129 free (a.arg);
130
131 if (printf_fetchargs (args, &a) < 0)
132 {
133 CLEANUP ();
134 errno = EINVAL;
135 return NULL;
136 }
137
138 {
139 size_t buf_neededlength;
140 CHAR_T *buf;
141 CHAR_T *buf_malloced;
142 const CHAR_T *cp;
143 size_t i;
144 DIRECTIVE *dp;
145 /* Output string accumulator. */
146 CHAR_T *result;
147 size_t allocated;
148 size_t length;
149
150 /* Allocate a small buffer that will hold a directive passed to
151 sprintf or snprintf. */
152 buf_neededlength =
153 xsum4 (7, d.max_width_length, d.max_precision_length, 6);
154 #if HAVE_ALLOCA
155 if (buf_neededlength < 4000 / sizeof (CHAR_T))
156 {
157 buf = (CHAR_T *) alloca (buf_neededlength * sizeof (CHAR_T));
158 buf_malloced = NULL;
159 }
160 else
161 #endif
162 {
163 size_t buf_memsize = xtimes (buf_neededlength, sizeof (CHAR_T));
164 if (size_overflow_p (buf_memsize))
165 goto out_of_memory_1;
166 buf = (CHAR_T *) malloc (buf_memsize);
167 if (buf == NULL)
168 goto out_of_memory_1;
169 buf_malloced = buf;
170 }
171
172 if (resultbuf != NULL)
173 {
174 result = resultbuf;
175 allocated = *lengthp;
176 }
177 else
178 {
179 result = NULL;
180 allocated = 0;
181 }
182 length = 0;
183 /* Invariants:
184 result is either == resultbuf or == NULL or malloc-allocated.
185 If length > 0, then result != NULL. */
186
187 /* Ensures that allocated >= needed. Aborts through a jump to
188 out_of_memory if needed is SIZE_MAX or otherwise too big. */
189 #define ENSURE_ALLOCATION(needed) \
190 if ((needed) > allocated) \
191 { \
192 size_t memory_size; \
193 CHAR_T *memory; \
194 \
195 allocated = (allocated > 0 ? xtimes (allocated, 2) : 12); \
196 if ((needed) > allocated) \
197 allocated = (needed); \
198 memory_size = xtimes (allocated, sizeof (CHAR_T)); \
199 if (size_overflow_p (memory_size)) \
200 goto out_of_memory; \
201 if (result == resultbuf || result == NULL) \
202 memory = (CHAR_T *) malloc (memory_size); \
203 else \
204 memory = (CHAR_T *) realloc (result, memory_size); \
205 if (memory == NULL) \
206 goto out_of_memory; \
207 if (result == resultbuf && length > 0) \
208 memcpy (memory, result, length * sizeof (CHAR_T)); \
209 result = memory; \
210 }
211
212 for (cp = format, i = 0, dp = &d.dir[0]; ; cp = dp->dir_end, i++, dp++)
213 {
214 if (cp != dp->dir_start)
215 {
216 size_t n = dp->dir_start - cp;
217 size_t augmented_length = xsum (length, n);
218
219 ENSURE_ALLOCATION (augmented_length);
220 memcpy (result + length, cp, n * sizeof (CHAR_T));
221 length = augmented_length;
222 }
223 if (i == d.count)
224 break;
225
226 /* Execute a single directive. */
227 if (dp->conversion == '%')
228 {
229 size_t augmented_length;
230
231 if (!(dp->arg_index == ARG_NONE))
232 abort ();
233 augmented_length = xsum (length, 1);
234 ENSURE_ALLOCATION (augmented_length);
235 result[length] = '%';
236 length = augmented_length;
237 }
238 else
239 {
240 if (!(dp->arg_index != ARG_NONE))
241 abort ();
242
243 if (dp->conversion == 'n')
244 {
245 switch (a.arg[dp->arg_index].type)
246 {
247 case TYPE_COUNT_SCHAR_POINTER:
248 *a.arg[dp->arg_index].a.a_count_schar_pointer = length;
249 break;
250 case TYPE_COUNT_SHORT_POINTER:
251 *a.arg[dp->arg_index].a.a_count_short_pointer = length;
252 break;
253 case TYPE_COUNT_INT_POINTER:
254 *a.arg[dp->arg_index].a.a_count_int_pointer = length;
255 break;
256 case TYPE_COUNT_LONGINT_POINTER:
257 *a.arg[dp->arg_index].a.a_count_longint_pointer = length;
258 break;
259 #ifdef HAVE_LONG_LONG
260 case TYPE_COUNT_LONGLONGINT_POINTER:
261 *a.arg[dp->arg_index].a.a_count_longlongint_pointer = length;
262 break;
263 #endif
264 default:
265 abort ();
266 }
267 }
268 else
269 {
270 arg_type type = a.arg[dp->arg_index].type;
271 CHAR_T *p;
272 unsigned int prefix_count;
273 int prefixes[2];
274 #if !USE_SNPRINTF
275 size_t tmp_length;
276 CHAR_T tmpbuf[700];
277 CHAR_T *tmp;
278
279 /* Allocate a temporary buffer of sufficient size for calling
280 sprintf. */
281 {
282 size_t width;
283 size_t precision;
284
285 width = 0;
286 if (dp->width_start != dp->width_end)
287 {
288 if (dp->width_arg_index != ARG_NONE)
289 {
290 int arg;
291
292 if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
293 abort ();
294 arg = a.arg[dp->width_arg_index].a.a_int;
295 width = (arg < 0 ? (unsigned int) (-arg) : arg);
296 }
297 else
298 {
299 const CHAR_T *digitp = dp->width_start;
300
301 do
302 width = xsum (xtimes (width, 10), *digitp++ - '0');
303 while (digitp != dp->width_end);
304 }
305 }
306
307 precision = 6;
308 if (dp->precision_start != dp->precision_end)
309 {
310 if (dp->precision_arg_index != ARG_NONE)
311 {
312 int arg;
313
314 if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
315 abort ();
316 arg = a.arg[dp->precision_arg_index].a.a_int;
317 precision = (arg < 0 ? 0 : arg);
318 }
319 else
320 {
321 const CHAR_T *digitp = dp->precision_start + 1;
322
323 precision = 0;
324 while (digitp != dp->precision_end)
325 precision = xsum (xtimes (precision, 10), *digitp++ - '0');
326 }
327 }
328
329 switch (dp->conversion)
330 {
331
332 case 'd': case 'i': case 'u':
333 # ifdef HAVE_LONG_LONG
334 if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
335 tmp_length =
336 (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
337 * 0.30103 /* binary -> decimal */
338 * 2 /* estimate for FLAG_GROUP */
339 )
340 + 1 /* turn floor into ceil */
341 + 1; /* account for leading sign */
342 else
343 # endif
344 if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
345 tmp_length =
346 (unsigned int) (sizeof (unsigned long) * CHAR_BIT
347 * 0.30103 /* binary -> decimal */
348 * 2 /* estimate for FLAG_GROUP */
349 )
350 + 1 /* turn floor into ceil */
351 + 1; /* account for leading sign */
352 else
353 tmp_length =
354 (unsigned int) (sizeof (unsigned int) * CHAR_BIT
355 * 0.30103 /* binary -> decimal */
356 * 2 /* estimate for FLAG_GROUP */
357 )
358 + 1 /* turn floor into ceil */
359 + 1; /* account for leading sign */
360 break;
361
362 case 'o':
363 # ifdef HAVE_LONG_LONG
364 if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
365 tmp_length =
366 (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
367 * 0.333334 /* binary -> octal */
368 )
369 + 1 /* turn floor into ceil */
370 + 1; /* account for leading sign */
371 else
372 # endif
373 if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
374 tmp_length =
375 (unsigned int) (sizeof (unsigned long) * CHAR_BIT
376 * 0.333334 /* binary -> octal */
377 )
378 + 1 /* turn floor into ceil */
379 + 1; /* account for leading sign */
380 else
381 tmp_length =
382 (unsigned int) (sizeof (unsigned int) * CHAR_BIT
383 * 0.333334 /* binary -> octal */
384 )
385 + 1 /* turn floor into ceil */
386 + 1; /* account for leading sign */
387 break;
388
389 case 'x': case 'X':
390 # ifdef HAVE_LONG_LONG
391 if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
392 tmp_length =
393 (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
394 * 0.25 /* binary -> hexadecimal */
395 )
396 + 1 /* turn floor into ceil */
397 + 2; /* account for leading sign or alternate form */
398 else
399 # endif
400 if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
401 tmp_length =
402 (unsigned int) (sizeof (unsigned long) * CHAR_BIT
403 * 0.25 /* binary -> hexadecimal */
404 )
405 + 1 /* turn floor into ceil */
406 + 2; /* account for leading sign or alternate form */
407 else
408 tmp_length =
409 (unsigned int) (sizeof (unsigned int) * CHAR_BIT
410 * 0.25 /* binary -> hexadecimal */
411 )
412 + 1 /* turn floor into ceil */
413 + 2; /* account for leading sign or alternate form */
414 break;
415
416 case 'f': case 'F':
417 # ifdef HAVE_LONG_DOUBLE
418 if (type == TYPE_LONGDOUBLE)
419 tmp_length =
420 (unsigned int) (LDBL_MAX_EXP
421 * 0.30103 /* binary -> decimal */
422 * 2 /* estimate for FLAG_GROUP */
423 )
424 + 1 /* turn floor into ceil */
425 + 10; /* sign, decimal point etc. */
426 else
427 # endif
428 tmp_length =
429 (unsigned int) (DBL_MAX_EXP
430 * 0.30103 /* binary -> decimal */
431 * 2 /* estimate for FLAG_GROUP */
432 )
433 + 1 /* turn floor into ceil */
434 + 10; /* sign, decimal point etc. */
435 tmp_length = xsum (tmp_length, precision);
436 break;
437
438 case 'e': case 'E': case 'g': case 'G':
439 case 'a': case 'A':
440 tmp_length =
441 12; /* sign, decimal point, exponent etc. */
442 tmp_length = xsum (tmp_length, precision);
443 break;
444
445 case 'c':
446 # if defined HAVE_WINT_T && !WIDE_CHAR_VERSION
447 if (type == TYPE_WIDE_CHAR)
448 tmp_length = MB_CUR_MAX;
449 else
450 # endif
451 tmp_length = 1;
452 break;
453
454 case 's':
455 # ifdef HAVE_WCHAR_T
456 if (type == TYPE_WIDE_STRING)
457 {
458 tmp_length =
459 local_wcslen (a.arg[dp->arg_index].a.a_wide_string);
460
461 # if !WIDE_CHAR_VERSION
462 tmp_length = xtimes (tmp_length, MB_CUR_MAX);
463 # endif
464 }
465 else
466 # endif
467 tmp_length = strlen (a.arg[dp->arg_index].a.a_string);
468 break;
469
470 case 'p':
471 tmp_length =
472 (unsigned int) (sizeof (void *) * CHAR_BIT
473 * 0.25 /* binary -> hexadecimal */
474 )
475 + 1 /* turn floor into ceil */
476 + 2; /* account for leading 0x */
477 break;
478
479 default:
480 abort ();
481 }
482
483 if (tmp_length < width)
484 tmp_length = width;
485
486 tmp_length = xsum (tmp_length, 1); /* account for trailing NUL */
487 }
488
489 if (tmp_length <= sizeof (tmpbuf) / sizeof (CHAR_T))
490 tmp = tmpbuf;
491 else
492 {
493 size_t tmp_memsize = xtimes (tmp_length, sizeof (CHAR_T));
494
495 if (size_overflow_p (tmp_memsize))
496 /* Overflow, would lead to out of memory. */
497 goto out_of_memory;
498 tmp = (CHAR_T *) malloc (tmp_memsize);
499 if (tmp == NULL)
500 /* Out of memory. */
501 goto out_of_memory;
502 }
503 #endif
504
505 /* Construct the format string for calling snprintf or
506 sprintf. */
507 p = buf;
508 *p++ = '%';
509 if (dp->flags & FLAG_GROUP)
510 *p++ = '\'';
511 if (dp->flags & FLAG_LEFT)
512 *p++ = '-';
513 if (dp->flags & FLAG_SHOWSIGN)
514 *p++ = '+';
515 if (dp->flags & FLAG_SPACE)
516 *p++ = ' ';
517 if (dp->flags & FLAG_ALT)
518 *p++ = '#';
519 if (dp->flags & FLAG_ZERO)
520 *p++ = '0';
521 if (dp->width_start != dp->width_end)
522 {
523 size_t n = dp->width_end - dp->width_start;
524 memcpy (p, dp->width_start, n * sizeof (CHAR_T));
525 p += n;
526 }
527 if (dp->precision_start != dp->precision_end)
528 {
529 size_t n = dp->precision_end - dp->precision_start;
530 memcpy (p, dp->precision_start, n * sizeof (CHAR_T));
531 p += n;
532 }
533
534 switch (type)
535 {
536 #ifdef HAVE_LONG_LONG
537 case TYPE_LONGLONGINT:
538 case TYPE_ULONGLONGINT:
539 *p++ = 'l';
540 /*FALLTHROUGH*/
541 #endif
542 case TYPE_LONGINT:
543 case TYPE_ULONGINT:
544 #ifdef HAVE_WINT_T
545 case TYPE_WIDE_CHAR:
546 #endif
547 #ifdef HAVE_WCHAR_T
548 case TYPE_WIDE_STRING:
549 #endif
550 *p++ = 'l';
551 break;
552 #ifdef HAVE_LONG_DOUBLE
553 case TYPE_LONGDOUBLE:
554 *p++ = 'L';
555 break;
556 #endif
557 default:
558 break;
559 }
560 *p = dp->conversion;
561 #if USE_SNPRINTF
562 p[1] = '%';
563 p[2] = 'n';
564 p[3] = '\0';
565 #else
566 p[1] = '\0';
567 #endif
568
569 /* Construct the arguments for calling snprintf or sprintf. */
570 prefix_count = 0;
571 if (dp->width_arg_index != ARG_NONE)
572 {
573 if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
574 abort ();
575 prefixes[prefix_count++] = a.arg[dp->width_arg_index].a.a_int;
576 }
577 if (dp->precision_arg_index != ARG_NONE)
578 {
579 if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
580 abort ();
581 prefixes[prefix_count++] = a.arg[dp->precision_arg_index].a.a_int;
582 }
583
584 #if USE_SNPRINTF
585 /* Prepare checking whether snprintf returns the count
586 via %n. */
587 ENSURE_ALLOCATION (xsum (length, 1));
588 result[length] = '\0';
589 #endif
590
591 for (;;)
592 {
593 size_t maxlen;
594 int count;
595 int retcount;
596
597 maxlen = allocated - length;
598 count = -1;
599 retcount = 0;
600
601 #if USE_SNPRINTF
602 # define SNPRINTF_BUF(arg) \
603 switch (prefix_count) \
604 { \
605 case 0: \
606 retcount = SNPRINTF (result + length, maxlen, buf, \
607 arg, &count); \
608 break; \
609 case 1: \
610 retcount = SNPRINTF (result + length, maxlen, buf, \
611 prefixes[0], arg, &count); \
612 break; \
613 case 2: \
614 retcount = SNPRINTF (result + length, maxlen, buf, \
615 prefixes[0], prefixes[1], arg, \
616 &count); \
617 break; \
618 default: \
619 abort (); \
620 }
621 #else
622 # define SNPRINTF_BUF(arg) \
623 switch (prefix_count) \
624 { \
625 case 0: \
626 count = sprintf (tmp, buf, arg); \
627 break; \
628 case 1: \
629 count = sprintf (tmp, buf, prefixes[0], arg); \
630 break; \
631 case 2: \
632 count = sprintf (tmp, buf, prefixes[0], prefixes[1],\
633 arg); \
634 break; \
635 default: \
636 abort (); \
637 }
638 #endif
639
640 switch (type)
641 {
642 case TYPE_SCHAR:
643 {
644 int arg = a.arg[dp->arg_index].a.a_schar;
645 SNPRINTF_BUF (arg);
646 }
647 break;
648 case TYPE_UCHAR:
649 {
650 unsigned int arg = a.arg[dp->arg_index].a.a_uchar;
651 SNPRINTF_BUF (arg);
652 }
653 break;
654 case TYPE_SHORT:
655 {
656 int arg = a.arg[dp->arg_index].a.a_short;
657 SNPRINTF_BUF (arg);
658 }
659 break;
660 case TYPE_USHORT:
661 {
662 unsigned int arg = a.arg[dp->arg_index].a.a_ushort;
663 SNPRINTF_BUF (arg);
664 }
665 break;
666 case TYPE_INT:
667 {
668 int arg = a.arg[dp->arg_index].a.a_int;
669 SNPRINTF_BUF (arg);
670 }
671 break;
672 case TYPE_UINT:
673 {
674 unsigned int arg = a.arg[dp->arg_index].a.a_uint;
675 SNPRINTF_BUF (arg);
676 }
677 break;
678 case TYPE_LONGINT:
679 {
680 long int arg = a.arg[dp->arg_index].a.a_longint;
681 SNPRINTF_BUF (arg);
682 }
683 break;
684 case TYPE_ULONGINT:
685 {
686 unsigned long int arg = a.arg[dp->arg_index].a.a_ulongint;
687 SNPRINTF_BUF (arg);
688 }
689 break;
690 #ifdef HAVE_LONG_LONG
691 case TYPE_LONGLONGINT:
692 {
693 long long int arg = a.arg[dp->arg_index].a.a_longlongint;
694 SNPRINTF_BUF (arg);
695 }
696 break;
697 case TYPE_ULONGLONGINT:
698 {
699 unsigned long long int arg = a.arg[dp->arg_index].a.a_ulonglongint;
700 SNPRINTF_BUF (arg);
701 }
702 break;
703 #endif
704 case TYPE_DOUBLE:
705 {
706 double arg = a.arg[dp->arg_index].a.a_double;
707 SNPRINTF_BUF (arg);
708 }
709 break;
710 #ifdef HAVE_LONG_DOUBLE
711 case TYPE_LONGDOUBLE:
712 {
713 long double arg = a.arg[dp->arg_index].a.a_longdouble;
714 SNPRINTF_BUF (arg);
715 }
716 break;
717 #endif
718 case TYPE_CHAR:
719 {
720 int arg = a.arg[dp->arg_index].a.a_char;
721 SNPRINTF_BUF (arg);
722 }
723 break;
724 #ifdef HAVE_WINT_T
725 case TYPE_WIDE_CHAR:
726 {
727 wint_t arg = a.arg[dp->arg_index].a.a_wide_char;
728 SNPRINTF_BUF (arg);
729 }
730 break;
731 #endif
732 case TYPE_STRING:
733 {
734 const char *arg = a.arg[dp->arg_index].a.a_string;
735 SNPRINTF_BUF (arg);
736 }
737 break;
738 #ifdef HAVE_WCHAR_T
739 case TYPE_WIDE_STRING:
740 {
741 const wchar_t *arg = a.arg[dp->arg_index].a.a_wide_string;
742 SNPRINTF_BUF (arg);
743 }
744 break;
745 #endif
746 case TYPE_POINTER:
747 {
748 void *arg = a.arg[dp->arg_index].a.a_pointer;
749 SNPRINTF_BUF (arg);
750 }
751 break;
752 default:
753 abort ();
754 }
755
756 #if USE_SNPRINTF
757 /* Portability: Not all implementations of snprintf()
758 are ISO C 99 compliant. Determine the number of
759 bytes that snprintf() has produced or would have
760 produced. */
761 if (count >= 0)
762 {
763 /* Verify that snprintf() has NUL-terminated its
764 result. */
765 if (count < maxlen && result[length + count] != '\0')
766 abort ();
767 /* Portability hack. */
768 if (retcount > count)
769 count = retcount;
770 }
771 else
772 {
773 /* snprintf() doesn't understand the '%n'
774 directive. */
775 if (p[1] != '\0')
776 {
777 /* Don't use the '%n' directive; instead, look
778 at the snprintf() return value. */
779 p[1] = '\0';
780 continue;
781 }
782 else
783 {
784 /* Look at the snprintf() return value. */
785 if (retcount < 0)
786 {
787 /* HP-UX 10.20 snprintf() is doubly deficient:
788 It doesn't understand the '%n' directive,
789 *and* it returns -1 (rather than the length
790 that would have been required) when the
791 buffer is too small. */
792 size_t bigger_need =
793 xsum (xtimes (allocated, 2), 12);
794 ENSURE_ALLOCATION (bigger_need);
795 continue;
796 }
797 else
798 count = retcount;
799 }
800 }
801 #endif
802
803 /* Attempt to handle failure. */
804 if (count < 0)
805 {
806 if (!(result == resultbuf || result == NULL))
807 free (result);
808 if (buf_malloced != NULL)
809 free (buf_malloced);
810 CLEANUP ();
811 errno = EINVAL;
812 return NULL;
813 }
814
815 #if !USE_SNPRINTF
816 if (count >= tmp_length)
817 /* tmp_length was incorrectly calculated - fix the
818 code above! */
819 abort ();
820 #endif
821
822 /* Make room for the result. */
823 if (count >= maxlen)
824 {
825 /* Need at least count bytes. But allocate
826 proportionally, to avoid looping eternally if
827 snprintf() reports a too small count. */
828 size_t n =
829 xmax (xsum (length, count), xtimes (allocated, 2));
830
831 ENSURE_ALLOCATION (n);
832 #if USE_SNPRINTF
833 continue;
834 #endif
835 }
836
837 #if USE_SNPRINTF
838 /* The snprintf() result did fit. */
839 #else
840 /* Append the sprintf() result. */
841 memcpy (result + length, tmp, count * sizeof (CHAR_T));
842 if (tmp != tmpbuf)
843 free (tmp);
844 #endif
845
846 length += count;
847 break;
848 }
849 }
850 }
851 }
852
853 /* Add the final NUL. */
854 ENSURE_ALLOCATION (xsum (length, 1));
855 result[length] = '\0';
856
857 if (result != resultbuf && length + 1 < allocated)
858 {
859 /* Shrink the allocated memory if possible. */
860 CHAR_T *memory;
861
862 memory = (CHAR_T *) realloc (result, (length + 1) * sizeof (CHAR_T));
863 if (memory != NULL)
864 result = memory;
865 }
866
867 if (buf_malloced != NULL)
868 free (buf_malloced);
869 CLEANUP ();
870 *lengthp = length;
871 if (length > INT_MAX)
872 goto length_overflow;
873 return result;
874
875 length_overflow:
876 /* We could produce such a big string, but its length doesn't fit into
877 an 'int'. POSIX says that snprintf() fails with errno = EOVERFLOW in
878 this case. */
879 if (result != resultbuf)
880 free (result);
881 errno = EOVERFLOW;
882 return NULL;
883
884 out_of_memory:
885 if (!(result == resultbuf || result == NULL))
886 free (result);
887 if (buf_malloced != NULL)
888 free (buf_malloced);
889 out_of_memory_1:
890 CLEANUP ();
891 errno = ENOMEM;
892 return NULL;
893 }
894 }
895
896 #undef SNPRINTF
897 #undef USE_SNPRINTF
898 #undef PRINTF_PARSE
899 #undef DIRECTIVES
900 #undef DIRECTIVE
901 #undef CHAR_T
902 #undef VASNPRINTF
903