Imported Upstream version 2.5.2p1
[debian/amanda] / gnulib / vasnprintf.c
1 /* vsprintf with automatic memory allocation.
2    Copyright (C) 1999, 2002-2007 Free Software Foundation, Inc.
3
4    This program is free software; you can redistribute it and/or modify
5    it under the terms of the GNU General Public License as published by
6    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
12    GNU General Public License for more details.
13
14    You should have received a copy of the GNU General Public License along
15    with this program; if not, write to the Free Software Foundation,
16    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
17
18 /* Tell glibc's <stdio.h> to provide a prototype for snprintf().
19    This must come before <config.h> because <config.h> may include
20    <features.h>, and once <features.h> has been included, it's too late.  */
21 #ifndef _GNU_SOURCE
22 # define _GNU_SOURCE    1
23 #endif
24
25 #include <config.h>
26 #ifndef IN_LIBINTL
27 # include <alloca.h>
28 #endif
29
30 /* Specification.  */
31 #if WIDE_CHAR_VERSION
32 # include "vasnwprintf.h"
33 #else
34 # include "vasnprintf.h"
35 #endif
36
37 #include <stdio.h>      /* snprintf(), sprintf() */
38 #include <stdlib.h>     /* abort(), malloc(), realloc(), free() */
39 #include <string.h>     /* memcpy(), strlen() */
40 #include <errno.h>      /* errno */
41 #include <limits.h>     /* CHAR_BIT */
42 #include <float.h>      /* DBL_MAX_EXP, LDBL_MAX_EXP */
43 #if WIDE_CHAR_VERSION
44 # include "wprintf-parse.h"
45 #else
46 # include "printf-parse.h"
47 #endif
48
49 /* Checked size_t computations.  */
50 #include "xsize.h"
51
52 #if HAVE_WCHAR_T
53 # if HAVE_WCSLEN
54 #  define local_wcslen wcslen
55 # else
56    /* Solaris 2.5.1 has wcslen() in a separate library libw.so. To avoid
57       a dependency towards this library, here is a local substitute.
58       Define this substitute only once, even if this file is included
59       twice in the same compilation unit.  */
60 #  ifndef local_wcslen_defined
61 #   define local_wcslen_defined 1
62 static size_t
63 local_wcslen (const wchar_t *s)
64 {
65   const wchar_t *ptr;
66
67   for (ptr = s; *ptr != (wchar_t) 0; ptr++)
68     ;
69   return ptr - s;
70 }
71 #  endif
72 # endif
73 #endif
74
75 #if WIDE_CHAR_VERSION
76 # define VASNPRINTF vasnwprintf
77 # define CHAR_T wchar_t
78 # define DIRECTIVE wchar_t_directive
79 # define DIRECTIVES wchar_t_directives
80 # define PRINTF_PARSE wprintf_parse
81 # define USE_SNPRINTF 1
82 # if HAVE_DECL__SNWPRINTF
83    /* On Windows, the function swprintf() has a different signature than
84       on Unix; we use the _snwprintf() function instead.  */
85 #  define SNPRINTF _snwprintf
86 # else
87    /* Unix.  */
88 #  define SNPRINTF swprintf
89 # endif
90 #else
91 # define VASNPRINTF vasnprintf
92 # define CHAR_T char
93 # define DIRECTIVE char_directive
94 # define DIRECTIVES char_directives
95 # define PRINTF_PARSE printf_parse
96 # define USE_SNPRINTF (HAVE_DECL__SNPRINTF || HAVE_SNPRINTF)
97 # if HAVE_DECL__SNPRINTF
98    /* Windows.  */
99 #  define SNPRINTF _snprintf
100 # else
101    /* Unix.  */
102 #  define SNPRINTF snprintf
103 # endif
104 #endif
105
106 CHAR_T *
107 VASNPRINTF (CHAR_T *resultbuf, size_t *lengthp, const CHAR_T *format, va_list args)
108 {
109   DIRECTIVES d;
110   arguments a;
111
112   if (PRINTF_PARSE (format, &d, &a) < 0)
113     {
114       errno = EINVAL;
115       return NULL;
116     }
117
118 #define CLEANUP() \
119   free (d.dir);                                                         \
120   if (a.arg)                                                            \
121     free (a.arg);
122
123   if (printf_fetchargs (args, &a) < 0)
124     {
125       CLEANUP ();
126       errno = EINVAL;
127       return NULL;
128     }
129
130   {
131     size_t buf_neededlength;
132     CHAR_T *buf;
133     CHAR_T *buf_malloced;
134     const CHAR_T *cp;
135     size_t i;
136     DIRECTIVE *dp;
137     /* Output string accumulator.  */
138     CHAR_T *result;
139     size_t allocated;
140     size_t length;
141
142     /* Allocate a small buffer that will hold a directive passed to
143        sprintf or snprintf.  */
144     buf_neededlength =
145       xsum4 (7, d.max_width_length, d.max_precision_length, 6);
146 #if HAVE_ALLOCA
147     if (buf_neededlength < 4000 / sizeof (CHAR_T))
148       {
149         buf = (CHAR_T *) alloca (buf_neededlength * sizeof (CHAR_T));
150         buf_malloced = NULL;
151       }
152     else
153 #endif
154       {
155         size_t buf_memsize = xtimes (buf_neededlength, sizeof (CHAR_T));
156         if (size_overflow_p (buf_memsize))
157           goto out_of_memory_1;
158         buf = (CHAR_T *) malloc (buf_memsize);
159         if (buf == NULL)
160           goto out_of_memory_1;
161         buf_malloced = buf;
162       }
163
164     if (resultbuf != NULL)
165       {
166         result = resultbuf;
167         allocated = *lengthp;
168       }
169     else
170       {
171         result = NULL;
172         allocated = 0;
173       }
174     length = 0;
175     /* Invariants:
176        result is either == resultbuf or == NULL or malloc-allocated.
177        If length > 0, then result != NULL.  */
178
179     /* Ensures that allocated >= needed.  Aborts through a jump to
180        out_of_memory if needed is SIZE_MAX or otherwise too big.  */
181 #define ENSURE_ALLOCATION(needed) \
182     if ((needed) > allocated)                                                \
183       {                                                                      \
184         size_t memory_size;                                                  \
185         CHAR_T *memory;                                                      \
186                                                                              \
187         allocated = (allocated > 0 ? xtimes (allocated, 2) : 12);            \
188         if ((needed) > allocated)                                            \
189           allocated = (needed);                                              \
190         memory_size = xtimes (allocated, sizeof (CHAR_T));                   \
191         if (size_overflow_p (memory_size))                                   \
192           goto out_of_memory;                                                \
193         if (result == resultbuf || result == NULL)                           \
194           memory = (CHAR_T *) malloc (memory_size);                          \
195         else                                                                 \
196           memory = (CHAR_T *) realloc (result, memory_size);                 \
197         if (memory == NULL)                                                  \
198           goto out_of_memory;                                                \
199         if (result == resultbuf && length > 0)                               \
200           memcpy (memory, result, length * sizeof (CHAR_T));                 \
201         result = memory;                                                     \
202       }
203
204     for (cp = format, i = 0, dp = &d.dir[0]; ; cp = dp->dir_end, i++, dp++)
205       {
206         if (cp != dp->dir_start)
207           {
208             size_t n = dp->dir_start - cp;
209             size_t augmented_length = xsum (length, n);
210
211             ENSURE_ALLOCATION (augmented_length);
212             memcpy (result + length, cp, n * sizeof (CHAR_T));
213             length = augmented_length;
214           }
215         if (i == d.count)
216           break;
217
218         /* Execute a single directive.  */
219         if (dp->conversion == '%')
220           {
221             size_t augmented_length;
222
223             if (!(dp->arg_index == ARG_NONE))
224               abort ();
225             augmented_length = xsum (length, 1);
226             ENSURE_ALLOCATION (augmented_length);
227             result[length] = '%';
228             length = augmented_length;
229           }
230         else
231           {
232             if (!(dp->arg_index != ARG_NONE))
233               abort ();
234
235             if (dp->conversion == 'n')
236               {
237                 switch (a.arg[dp->arg_index].type)
238                   {
239                   case TYPE_COUNT_SCHAR_POINTER:
240                     *a.arg[dp->arg_index].a.a_count_schar_pointer = length;
241                     break;
242                   case TYPE_COUNT_SHORT_POINTER:
243                     *a.arg[dp->arg_index].a.a_count_short_pointer = length;
244                     break;
245                   case TYPE_COUNT_INT_POINTER:
246                     *a.arg[dp->arg_index].a.a_count_int_pointer = length;
247                     break;
248                   case TYPE_COUNT_LONGINT_POINTER:
249                     *a.arg[dp->arg_index].a.a_count_longint_pointer = length;
250                     break;
251 #if HAVE_LONG_LONG_INT
252                   case TYPE_COUNT_LONGLONGINT_POINTER:
253                     *a.arg[dp->arg_index].a.a_count_longlongint_pointer = length;
254                     break;
255 #endif
256                   default:
257                     abort ();
258                   }
259               }
260             else
261               {
262                 arg_type type = a.arg[dp->arg_index].type;
263                 CHAR_T *p;
264                 unsigned int prefix_count;
265                 int prefixes[2];
266 #if !USE_SNPRINTF
267                 size_t tmp_length;
268                 CHAR_T tmpbuf[700];
269                 CHAR_T *tmp;
270
271                 /* Allocate a temporary buffer of sufficient size for calling
272                    sprintf.  */
273                 {
274                   size_t width;
275                   size_t precision;
276
277                   width = 0;
278                   if (dp->width_start != dp->width_end)
279                     {
280                       if (dp->width_arg_index != ARG_NONE)
281                         {
282                           int arg;
283
284                           if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
285                             abort ();
286                           arg = a.arg[dp->width_arg_index].a.a_int;
287                           width = (arg < 0 ? (unsigned int) (-arg) : arg);
288                         }
289                       else
290                         {
291                           const CHAR_T *digitp = dp->width_start;
292
293                           do
294                             width = xsum (xtimes (width, 10), *digitp++ - '0');
295                           while (digitp != dp->width_end);
296                         }
297                     }
298
299                   precision = 6;
300                   if (dp->precision_start != dp->precision_end)
301                     {
302                       if (dp->precision_arg_index != ARG_NONE)
303                         {
304                           int arg;
305
306                           if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
307                             abort ();
308                           arg = a.arg[dp->precision_arg_index].a.a_int;
309                           precision = (arg < 0 ? 0 : arg);
310                         }
311                       else
312                         {
313                           const CHAR_T *digitp = dp->precision_start + 1;
314
315                           precision = 0;
316                           while (digitp != dp->precision_end)
317                             precision = xsum (xtimes (precision, 10), *digitp++ - '0');
318                         }
319                     }
320
321                   switch (dp->conversion)
322                     {
323
324                     case 'd': case 'i': case 'u':
325 # if HAVE_LONG_LONG_INT
326                       if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
327                         tmp_length =
328                           (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
329                                           * 0.30103 /* binary -> decimal */
330                                          )
331                           + 1; /* turn floor into ceil */
332                       else
333 # endif
334                       if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
335                         tmp_length =
336                           (unsigned int) (sizeof (unsigned long) * CHAR_BIT
337                                           * 0.30103 /* binary -> decimal */
338                                          )
339                           + 1; /* turn floor into ceil */
340                       else
341                         tmp_length =
342                           (unsigned int) (sizeof (unsigned int) * CHAR_BIT
343                                           * 0.30103 /* binary -> decimal */
344                                          )
345                           + 1; /* turn floor into ceil */
346                       if (tmp_length < precision)
347                         tmp_length = precision;
348                       /* Multiply by 2, as an estimate for FLAG_GROUP.  */
349                       tmp_length = xsum (tmp_length, tmp_length);
350                       /* Add 1, to account for a leading sign.  */
351                       tmp_length = xsum (tmp_length, 1);
352                       break;
353
354                     case 'o':
355 # if HAVE_LONG_LONG_INT
356                       if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
357                         tmp_length =
358                           (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
359                                           * 0.333334 /* binary -> octal */
360                                          )
361                           + 1; /* turn floor into ceil */
362                       else
363 # endif
364                       if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
365                         tmp_length =
366                           (unsigned int) (sizeof (unsigned long) * CHAR_BIT
367                                           * 0.333334 /* binary -> octal */
368                                          )
369                           + 1; /* turn floor into ceil */
370                       else
371                         tmp_length =
372                           (unsigned int) (sizeof (unsigned int) * CHAR_BIT
373                                           * 0.333334 /* binary -> octal */
374                                          )
375                           + 1; /* turn floor into ceil */
376                       if (tmp_length < precision)
377                         tmp_length = precision;
378                       /* Add 1, to account for a leading sign.  */
379                       tmp_length = xsum (tmp_length, 1);
380                       break;
381
382                     case 'x': case 'X':
383 # if HAVE_LONG_LONG_INT
384                       if (type == TYPE_LONGLONGINT || type == TYPE_ULONGLONGINT)
385                         tmp_length =
386                           (unsigned int) (sizeof (unsigned long long) * CHAR_BIT
387                                           * 0.25 /* binary -> hexadecimal */
388                                          )
389                           + 1; /* turn floor into ceil */
390                       else
391 # endif
392                       if (type == TYPE_LONGINT || type == TYPE_ULONGINT)
393                         tmp_length =
394                           (unsigned int) (sizeof (unsigned long) * CHAR_BIT
395                                           * 0.25 /* binary -> hexadecimal */
396                                          )
397                           + 1; /* turn floor into ceil */
398                       else
399                         tmp_length =
400                           (unsigned int) (sizeof (unsigned int) * CHAR_BIT
401                                           * 0.25 /* binary -> hexadecimal */
402                                          )
403                           + 1; /* turn floor into ceil */
404                       if (tmp_length < precision)
405                         tmp_length = precision;
406                       /* Add 2, to account for a leading sign or alternate form.  */
407                       tmp_length = xsum (tmp_length, 2);
408                       break;
409
410                     case 'f': case 'F':
411 # if HAVE_LONG_DOUBLE
412                       if (type == TYPE_LONGDOUBLE)
413                         tmp_length =
414                           (unsigned int) (LDBL_MAX_EXP
415                                           * 0.30103 /* binary -> decimal */
416                                           * 2 /* estimate for FLAG_GROUP */
417                                          )
418                           + 1 /* turn floor into ceil */
419                           + 10; /* sign, decimal point etc. */
420                       else
421 # endif
422                         tmp_length =
423                           (unsigned int) (DBL_MAX_EXP
424                                           * 0.30103 /* binary -> decimal */
425                                           * 2 /* estimate for FLAG_GROUP */
426                                          )
427                           + 1 /* turn floor into ceil */
428                           + 10; /* sign, decimal point etc. */
429                       tmp_length = xsum (tmp_length, precision);
430                       break;
431
432                     case 'e': case 'E': case 'g': case 'G':
433                     case 'a': case 'A':
434                       tmp_length =
435                         12; /* sign, decimal point, exponent etc. */
436                       tmp_length = xsum (tmp_length, precision);
437                       break;
438
439                     case 'c':
440 # if HAVE_WINT_T && !WIDE_CHAR_VERSION
441                       if (type == TYPE_WIDE_CHAR)
442                         tmp_length = MB_CUR_MAX;
443                       else
444 # endif
445                         tmp_length = 1;
446                       break;
447
448                     case 's':
449 # if HAVE_WCHAR_T
450                       if (type == TYPE_WIDE_STRING)
451                         {
452                           tmp_length =
453                             local_wcslen (a.arg[dp->arg_index].a.a_wide_string);
454
455 #  if !WIDE_CHAR_VERSION
456                           tmp_length = xtimes (tmp_length, MB_CUR_MAX);
457 #  endif
458                         }
459                       else
460 # endif
461                         tmp_length = strlen (a.arg[dp->arg_index].a.a_string);
462                       break;
463
464                     case 'p':
465                       tmp_length =
466                         (unsigned int) (sizeof (void *) * CHAR_BIT
467                                         * 0.25 /* binary -> hexadecimal */
468                                        )
469                           + 1 /* turn floor into ceil */
470                           + 2; /* account for leading 0x */
471                       break;
472
473                     default:
474                       abort ();
475                     }
476
477                   if (tmp_length < width)
478                     tmp_length = width;
479
480                   tmp_length = xsum (tmp_length, 1); /* account for trailing NUL */
481                 }
482
483                 if (tmp_length <= sizeof (tmpbuf) / sizeof (CHAR_T))
484                   tmp = tmpbuf;
485                 else
486                   {
487                     size_t tmp_memsize = xtimes (tmp_length, sizeof (CHAR_T));
488
489                     if (size_overflow_p (tmp_memsize))
490                       /* Overflow, would lead to out of memory.  */
491                       goto out_of_memory;
492                     tmp = (CHAR_T *) malloc (tmp_memsize);
493                     if (tmp == NULL)
494                       /* Out of memory.  */
495                       goto out_of_memory;
496                   }
497 #endif
498
499                 /* Construct the format string for calling snprintf or
500                    sprintf.  */
501                 p = buf;
502                 *p++ = '%';
503                 if (dp->flags & FLAG_GROUP)
504                   *p++ = '\'';
505                 if (dp->flags & FLAG_LEFT)
506                   *p++ = '-';
507                 if (dp->flags & FLAG_SHOWSIGN)
508                   *p++ = '+';
509                 if (dp->flags & FLAG_SPACE)
510                   *p++ = ' ';
511                 if (dp->flags & FLAG_ALT)
512                   *p++ = '#';
513                 if (dp->flags & FLAG_ZERO)
514                   *p++ = '0';
515                 if (dp->width_start != dp->width_end)
516                   {
517                     size_t n = dp->width_end - dp->width_start;
518                     memcpy (p, dp->width_start, n * sizeof (CHAR_T));
519                     p += n;
520                   }
521                 if (dp->precision_start != dp->precision_end)
522                   {
523                     size_t n = dp->precision_end - dp->precision_start;
524                     memcpy (p, dp->precision_start, n * sizeof (CHAR_T));
525                     p += n;
526                   }
527
528                 switch (type)
529                   {
530 #if HAVE_LONG_LONG_INT
531                   case TYPE_LONGLONGINT:
532                   case TYPE_ULONGLONGINT:
533                     *p++ = 'l';
534                     /*FALLTHROUGH*/
535 #endif
536                   case TYPE_LONGINT:
537                   case TYPE_ULONGINT:
538 #if HAVE_WINT_T
539                   case TYPE_WIDE_CHAR:
540 #endif
541 #if HAVE_WCHAR_T
542                   case TYPE_WIDE_STRING:
543 #endif
544                     *p++ = 'l';
545                     break;
546 #if HAVE_LONG_DOUBLE
547                   case TYPE_LONGDOUBLE:
548                     *p++ = 'L';
549                     break;
550 #endif
551                   default:
552                     break;
553                   }
554                 *p = dp->conversion;
555 #if USE_SNPRINTF
556                 p[1] = '%';
557                 p[2] = 'n';
558                 p[3] = '\0';
559 #else
560                 p[1] = '\0';
561 #endif
562
563                 /* Construct the arguments for calling snprintf or sprintf.  */
564                 prefix_count = 0;
565                 if (dp->width_arg_index != ARG_NONE)
566                   {
567                     if (!(a.arg[dp->width_arg_index].type == TYPE_INT))
568                       abort ();
569                     prefixes[prefix_count++] = a.arg[dp->width_arg_index].a.a_int;
570                   }
571                 if (dp->precision_arg_index != ARG_NONE)
572                   {
573                     if (!(a.arg[dp->precision_arg_index].type == TYPE_INT))
574                       abort ();
575                     prefixes[prefix_count++] = a.arg[dp->precision_arg_index].a.a_int;
576                   }
577
578 #if USE_SNPRINTF
579                 /* Prepare checking whether snprintf returns the count
580                    via %n.  */
581                 ENSURE_ALLOCATION (xsum (length, 1));
582                 result[length] = '\0';
583 #endif
584
585                 for (;;)
586                   {
587                     size_t maxlen;
588                     int count;
589                     int retcount;
590
591                     maxlen = allocated - length;
592                     count = -1;
593                     retcount = 0;
594
595 #if USE_SNPRINTF
596 # define SNPRINTF_BUF(arg) \
597                     switch (prefix_count)                                   \
598                       {                                                     \
599                       case 0:                                               \
600                         retcount = SNPRINTF (result + length, maxlen, buf,  \
601                                              arg, &count);                  \
602                         break;                                              \
603                       case 1:                                               \
604                         retcount = SNPRINTF (result + length, maxlen, buf,  \
605                                              prefixes[0], arg, &count);     \
606                         break;                                              \
607                       case 2:                                               \
608                         retcount = SNPRINTF (result + length, maxlen, buf,  \
609                                              prefixes[0], prefixes[1], arg, \
610                                              &count);                       \
611                         break;                                              \
612                       default:                                              \
613                         abort ();                                           \
614                       }
615 #else
616 # define SNPRINTF_BUF(arg) \
617                     switch (prefix_count)                                   \
618                       {                                                     \
619                       case 0:                                               \
620                         count = sprintf (tmp, buf, arg);                    \
621                         break;                                              \
622                       case 1:                                               \
623                         count = sprintf (tmp, buf, prefixes[0], arg);       \
624                         break;                                              \
625                       case 2:                                               \
626                         count = sprintf (tmp, buf, prefixes[0], prefixes[1],\
627                                          arg);                              \
628                         break;                                              \
629                       default:                                              \
630                         abort ();                                           \
631                       }
632 #endif
633
634                     switch (type)
635                       {
636                       case TYPE_SCHAR:
637                         {
638                           int arg = a.arg[dp->arg_index].a.a_schar;
639                           SNPRINTF_BUF (arg);
640                         }
641                         break;
642                       case TYPE_UCHAR:
643                         {
644                           unsigned int arg = a.arg[dp->arg_index].a.a_uchar;
645                           SNPRINTF_BUF (arg);
646                         }
647                         break;
648                       case TYPE_SHORT:
649                         {
650                           int arg = a.arg[dp->arg_index].a.a_short;
651                           SNPRINTF_BUF (arg);
652                         }
653                         break;
654                       case TYPE_USHORT:
655                         {
656                           unsigned int arg = a.arg[dp->arg_index].a.a_ushort;
657                           SNPRINTF_BUF (arg);
658                         }
659                         break;
660                       case TYPE_INT:
661                         {
662                           int arg = a.arg[dp->arg_index].a.a_int;
663                           SNPRINTF_BUF (arg);
664                         }
665                         break;
666                       case TYPE_UINT:
667                         {
668                           unsigned int arg = a.arg[dp->arg_index].a.a_uint;
669                           SNPRINTF_BUF (arg);
670                         }
671                         break;
672                       case TYPE_LONGINT:
673                         {
674                           long int arg = a.arg[dp->arg_index].a.a_longint;
675                           SNPRINTF_BUF (arg);
676                         }
677                         break;
678                       case TYPE_ULONGINT:
679                         {
680                           unsigned long int arg = a.arg[dp->arg_index].a.a_ulongint;
681                           SNPRINTF_BUF (arg);
682                         }
683                         break;
684 #if HAVE_LONG_LONG_INT
685                       case TYPE_LONGLONGINT:
686                         {
687                           long long int arg = a.arg[dp->arg_index].a.a_longlongint;
688                           SNPRINTF_BUF (arg);
689                         }
690                         break;
691                       case TYPE_ULONGLONGINT:
692                         {
693                           unsigned long long int arg = a.arg[dp->arg_index].a.a_ulonglongint;
694                           SNPRINTF_BUF (arg);
695                         }
696                         break;
697 #endif
698                       case TYPE_DOUBLE:
699                         {
700                           double arg = a.arg[dp->arg_index].a.a_double;
701                           SNPRINTF_BUF (arg);
702                         }
703                         break;
704 #if HAVE_LONG_DOUBLE
705                       case TYPE_LONGDOUBLE:
706                         {
707                           long double arg = a.arg[dp->arg_index].a.a_longdouble;
708                           SNPRINTF_BUF (arg);
709                         }
710                         break;
711 #endif
712                       case TYPE_CHAR:
713                         {
714                           int arg = a.arg[dp->arg_index].a.a_char;
715                           SNPRINTF_BUF (arg);
716                         }
717                         break;
718 #if HAVE_WINT_T
719                       case TYPE_WIDE_CHAR:
720                         {
721                           wint_t arg = a.arg[dp->arg_index].a.a_wide_char;
722                           SNPRINTF_BUF (arg);
723                         }
724                         break;
725 #endif
726                       case TYPE_STRING:
727                         {
728                           const char *arg = a.arg[dp->arg_index].a.a_string;
729                           SNPRINTF_BUF (arg);
730                         }
731                         break;
732 #if HAVE_WCHAR_T
733                       case TYPE_WIDE_STRING:
734                         {
735                           const wchar_t *arg = a.arg[dp->arg_index].a.a_wide_string;
736                           SNPRINTF_BUF (arg);
737                         }
738                         break;
739 #endif
740                       case TYPE_POINTER:
741                         {
742                           void *arg = a.arg[dp->arg_index].a.a_pointer;
743                           SNPRINTF_BUF (arg);
744                         }
745                         break;
746                       default:
747                         abort ();
748                       }
749
750 #if USE_SNPRINTF
751                     /* Portability: Not all implementations of snprintf()
752                        are ISO C 99 compliant.  Determine the number of
753                        bytes that snprintf() has produced or would have
754                        produced.  */
755                     if (count >= 0)
756                       {
757                         /* Verify that snprintf() has NUL-terminated its
758                            result.  */
759                         if (count < maxlen && result[length + count] != '\0')
760                           abort ();
761                         /* Portability hack.  */
762                         if (retcount > count)
763                           count = retcount;
764                       }
765                     else
766                       {
767                         /* snprintf() doesn't understand the '%n'
768                            directive.  */
769                         if (p[1] != '\0')
770                           {
771                             /* Don't use the '%n' directive; instead, look
772                                at the snprintf() return value.  */
773                             p[1] = '\0';
774                             continue;
775                           }
776                         else
777                           {
778                             /* Look at the snprintf() return value.  */
779                             if (retcount < 0)
780                               {
781                                 /* HP-UX 10.20 snprintf() is doubly deficient:
782                                    It doesn't understand the '%n' directive,
783                                    *and* it returns -1 (rather than the length
784                                    that would have been required) when the
785                                    buffer is too small.  */
786                                 size_t bigger_need =
787                                   xsum (xtimes (allocated, 2), 12);
788                                 ENSURE_ALLOCATION (bigger_need);
789                                 continue;
790                               }
791                             else
792                               count = retcount;
793                           }
794                       }
795 #endif
796
797                     /* Attempt to handle failure.  */
798                     if (count < 0)
799                       {
800                         if (!(result == resultbuf || result == NULL))
801                           free (result);
802                         if (buf_malloced != NULL)
803                           free (buf_malloced);
804                         CLEANUP ();
805                         errno = EINVAL;
806                         return NULL;
807                       }
808
809 #if !USE_SNPRINTF
810                     if (count >= tmp_length)
811                       /* tmp_length was incorrectly calculated - fix the
812                          code above!  */
813                       abort ();
814 #endif
815
816                     /* Make room for the result.  */
817                     if (count >= maxlen)
818                       {
819                         /* Need at least count bytes.  But allocate
820                            proportionally, to avoid looping eternally if
821                            snprintf() reports a too small count.  */
822                         size_t n =
823                           xmax (xsum (length, count), xtimes (allocated, 2));
824
825                         ENSURE_ALLOCATION (n);
826 #if USE_SNPRINTF
827                         continue;
828 #endif
829                       }
830
831 #if USE_SNPRINTF
832                     /* The snprintf() result did fit.  */
833 #else
834                     /* Append the sprintf() result.  */
835                     memcpy (result + length, tmp, count * sizeof (CHAR_T));
836                     if (tmp != tmpbuf)
837                       free (tmp);
838 #endif
839
840                     length += count;
841                     break;
842                   }
843               }
844           }
845       }
846
847     /* Add the final NUL.  */
848     ENSURE_ALLOCATION (xsum (length, 1));
849     result[length] = '\0';
850
851     if (result != resultbuf && length + 1 < allocated)
852       {
853         /* Shrink the allocated memory if possible.  */
854         CHAR_T *memory;
855
856         memory = (CHAR_T *) realloc (result, (length + 1) * sizeof (CHAR_T));
857         if (memory != NULL)
858           result = memory;
859       }
860
861     if (buf_malloced != NULL)
862       free (buf_malloced);
863     CLEANUP ();
864     *lengthp = length;
865     /* Note that we can produce a big string of a length > INT_MAX.  POSIX
866        says that snprintf() fails with errno = EOVERFLOW in this case, but
867        that's only because snprintf() returns an 'int'.  This function does
868        not have this limitation.  */
869     return result;
870
871   out_of_memory:
872     if (!(result == resultbuf || result == NULL))
873       free (result);
874     if (buf_malloced != NULL)
875       free (buf_malloced);
876   out_of_memory_1:
877     CLEANUP ();
878     errno = ENOMEM;
879     return NULL;
880   }
881 }
882
883 #undef SNPRINTF
884 #undef USE_SNPRINTF
885 #undef PRINTF_PARSE
886 #undef DIRECTIVES
887 #undef DIRECTIVE
888 #undef CHAR_T
889 #undef VASNPRINTF