Commit | Line | Data |
---|---|---|
24f98398 | 1 | /* Output like sprintf to a buffer of specified size. |
762b15be EZ |
2 | Also takes args differently: pass one pointer to the end |
3 | of the format string in addition to the format string itself. | |
73b0cd50 | 4 | Copyright (C) 1985, 2001-2011 Free Software Foundation, Inc. |
24f98398 JA |
5 | |
6 | This file is part of GNU Emacs. | |
7 | ||
9ec0b715 | 8 | GNU Emacs is free software: you can redistribute it and/or modify |
24f98398 | 9 | it under the terms of the GNU General Public License as published by |
9ec0b715 GM |
10 | the Free Software Foundation, either version 3 of the License, or |
11 | (at your option) any later version. | |
24f98398 JA |
12 | |
13 | GNU Emacs is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
9ec0b715 | 19 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
24f98398 | 20 | |
762b15be EZ |
21 | /* If you think about replacing this with some similar standard C function of |
22 | the printf family (such as vsnprintf), please note that this function | |
23 | supports the following Emacs-specific features: | |
24 | ||
25 | . For %c conversions, it produces a string with the multibyte representation | |
26 | of the (`int') argument, suitable for display in an Emacs buffer. | |
27 | ||
28 | . For %s and %c, when field width is specified (e.g., %25s), it accounts for | |
29 | the diplay width of each character, according to char-width-table. That | |
30 | is, it does not assume that each character takes one column on display. | |
31 | ||
32 | . If the size of the buffer is not enough to produce the formatted string in | |
33 | its entirety, it makes sure that truncation does not chop the last | |
34 | character in the middle of its multibyte sequence, producing an invalid | |
35 | sequence. | |
36 | ||
37 | . It accepts a pointer to the end of the format string, so the format string | |
38 | could include embedded null characters. | |
39 | ||
40 | . It signals an error if the length of the formatted string is about to | |
41 | overflow MOST_POSITIVE_FIXNUM, to avoid producing strings longer than what | |
42 | Emacs can handle. | |
43 | ||
44 | OTOH, this function supports only a small subset of the standard C formatted | |
45 | output facilities. E.g., %u and %ll are not supported, and precision is | |
825cd63c EZ |
46 | ignored %s and %c conversions. (See below for the detailed documentation of |
47 | what is supported.) However, this is okay, as this function is supposed to | |
48 | be called from `error' and similar functions, and thus does not need to | |
49 | support features beyond those in `Fformat', which is used by `error' on the | |
50 | Lisp level. */ | |
51 | ||
52 | /* This function supports the following %-sequences in the `format' | |
53 | argument: | |
54 | ||
55 | %s means print a string argument. | |
56 | %S is silently treated as %s, for loose compatibility with `Fformat'. | |
57 | %d means print a `signed int' argument in decimal. | |
825cd63c EZ |
58 | %o means print an `unsigned int' argument in octal. |
59 | %x means print an `unsigned int' argument in hex. | |
60 | %e means print a `double' argument in exponential notation. | |
61 | %f means print a `double' argument in decimal-point notation. | |
62 | %g means print a `double' argument in exponential notation | |
63 | or in decimal-point notation, whichever uses fewer characters. | |
64 | %c means print a `signed int' argument as a single character. | |
65 | %% means produce a literal % character. | |
66 | ||
94dcfacf EZ |
67 | A %-sequence may contain optional flag, width, and precision specifiers, and |
68 | a length modifier, as follows: | |
825cd63c | 69 | |
94dcfacf | 70 | %<flags><width><precision><length>character |
825cd63c | 71 | |
b71a1728 | 72 | where flags is [+ -0], width is [0-9]+, precision is .[0-9]+, and length |
62f19c19 PE |
73 | is empty or l or the value of the pD or pI or pMd (sans "d") macros. |
74 | Also, %% in a format stands for a single % in the output. A % that | |
75 | does not introduce a valid %-sequence causes undefined behavior. | |
825cd63c EZ |
76 | |
77 | The + flag character inserts a + before any positive number, while a space | |
94dcfacf EZ |
78 | inserts a space before any positive number; these flags only affect %d, %o, |
79 | %x, %e, %f, and %g sequences. The - and 0 flags affect the width specifier, | |
80 | as described below. For signed numerical arguments only, the ` ' (space) | |
81 | flag causes the result to be prefixed with a space character if it does not | |
82 | start with a sign (+ or -). | |
83 | ||
84 | The l (lower-case letter ell) length modifier is a `long' data type | |
85 | modifier: it is supported for %d, %o, and %x conversions of integral | |
54b8e3f7 | 86 | arguments, must immediately precede the conversion specifier, and means that |
94dcfacf | 87 | the respective argument is to be treated as `long int' or `unsigned long |
62f19c19 PE |
88 | int'. Similarly, the value of the pD macro means to use ptrdiff_t, |
89 | the value of the pI macro means to use EMACS_INT or EMACS_UINT, the | |
90 | value of the pMd etc. macros means to use intmax_t or uintmax_t, | |
91 | and the empty length modifier means `int' or `unsigned int'. | |
825cd63c EZ |
92 | |
93 | The width specifier supplies a lower limit for the length of the printed | |
94 | representation. The padding, if any, normally goes on the left, but it goes | |
95 | on the right if the - flag is present. The padding character is normally a | |
96 | space, but (for numerical arguments only) it is 0 if the 0 flag is present. | |
97 | The - flag takes precedence over the 0 flag. | |
98 | ||
99 | For %e, %f, and %g sequences, the number after the "." in the precision | |
100 | specifier says how many decimal places to show; if zero, the decimal point | |
101 | itself is omitted. For %s and %S, the precision specifier is ignored. */ | |
24f98398 | 102 | |
6d291527 | 103 | #include <config.h> |
24f98398 JA |
104 | #include <stdio.h> |
105 | #include <ctype.h> | |
d7306fe6 | 106 | #include <setjmp.h> |
be65c2f4 | 107 | #include <float.h> |
48236137 | 108 | #include <unistd.h> |
e6c3da20 | 109 | #include <limits.h> |
e6c3da20 | 110 | |
523e9291 RS |
111 | #include "lisp.h" |
112 | ||
a0ca925c KH |
113 | /* Since we use the macro CHAR_HEAD_P, we have to include this, but |
114 | don't have to include others because CHAR_HEAD_P does not contains | |
115 | another macro. */ | |
83be827a | 116 | #include "character.h" |
a0ca925c | 117 | |
92bc9a36 DN |
118 | #ifndef DBL_MAX_10_EXP |
119 | #define DBL_MAX_10_EXP 308 /* IEEE double */ | |
120 | #endif | |
121 | ||
f4c730d3 RS |
122 | /* Generate output from a format-spec FORMAT, |
123 | terminated at position FORMAT_END. | |
f40b429d | 124 | (*FORMAT_END is not part of the format, but must exist and be readable.) |
f4c730d3 | 125 | Output goes in BUFFER, which has room for BUFSIZE chars. |
f40b429d PE |
126 | BUFSIZE must be positive. If the output does not fit, truncate it |
127 | to fit and return BUFSIZE - 1; if this truncates a multibyte | |
128 | sequence, store '\0' into the sequence's first byte. | |
825cd63c EZ |
129 | Returns the number of bytes stored into BUFFER, excluding |
130 | the terminating null byte. Output is always null-terminated. | |
1513af9e RS |
131 | String arguments are passed as C strings. |
132 | Integers are passed as C integers. */ | |
f4c730d3 | 133 | |
c2d1e36d PE |
134 | ptrdiff_t |
135 | doprnt (char *buffer, ptrdiff_t bufsize, const char *format, | |
a8fe7202 | 136 | const char *format_end, va_list ap) |
24f98398 | 137 | { |
a8fe7202 | 138 | const char *fmt = format; /* Pointer into format string */ |
24f98398 | 139 | register char *bufptr = buffer; /* Pointer into output buffer.. */ |
03383aaf | 140 | |
f4c730d3 | 141 | /* Use this for sprintf unless we need something really big. */ |
be65c2f4 | 142 | char tembuf[DBL_MAX_10_EXP + 100]; |
03383aaf | 143 | |
f4c730d3 | 144 | /* Size of sprintf_buffer. */ |
c2d1e36d | 145 | ptrdiff_t size_allocated = sizeof (tembuf); |
03383aaf | 146 | |
f4c730d3 RS |
147 | /* Buffer to use for sprintf. Either tembuf or same as BIG_BUFFER. */ |
148 | char *sprintf_buffer = tembuf; | |
03383aaf | 149 | |
f4c730d3 | 150 | /* Buffer we have got with malloc. */ |
e6c3da20 | 151 | char *big_buffer = NULL; |
03383aaf | 152 | |
e6c3da20 | 153 | register size_t tem; |
7469ef5d | 154 | char *string; |
03383aaf BF |
155 | char fixed_buffer[20]; /* Default buffer for small formatting. */ |
156 | char *fmtcpy; | |
24f98398 | 157 | int minlen; |
7469ef5d | 158 | char charbuf[MAX_MULTIBYTE_LENGTH + 1]; /* Used for %c. */ |
825cd63c | 159 | USE_SAFE_ALLOCA; |
24f98398 JA |
160 | |
161 | if (format_end == 0) | |
162 | format_end = format + strlen (format); | |
163 | ||
c2d1e36d | 164 | if (format_end - format < sizeof (fixed_buffer) - 1) |
03383aaf BF |
165 | fmtcpy = fixed_buffer; |
166 | else | |
825cd63c | 167 | SAFE_ALLOCA (fmtcpy, char *, format_end - format + 1); |
03383aaf | 168 | |
24f98398 | 169 | bufsize--; |
03383aaf BF |
170 | |
171 | /* Loop until end of format string or buffer full. */ | |
94dcfacf | 172 | while (fmt < format_end && bufsize > 0) |
24f98398 JA |
173 | { |
174 | if (*fmt == '%') /* Check for a '%' character */ | |
175 | { | |
c2d1e36d | 176 | ptrdiff_t size_bound = 0; |
e6c3da20 | 177 | EMACS_INT width; /* Columns occupied by STRING on display. */ |
62f19c19 PE |
178 | enum { |
179 | pDlen = sizeof pD - 1, | |
180 | pIlen = sizeof pI - 1, | |
181 | pMlen = sizeof pMd - 2 | |
182 | }; | |
183 | enum { | |
184 | no_modifier, long_modifier, pD_modifier, pI_modifier, pM_modifier | |
185 | } length_modifier = no_modifier; | |
186 | static char const modifier_len[] = { 0, 1, pDlen, pIlen, pMlen }; | |
187 | int maxmlen = max (max (1, pDlen), max (pIlen, pMlen)); | |
188 | int mlen; | |
f4c730d3 | 189 | |
24f98398 | 190 | fmt++; |
d427b66a | 191 | /* Copy this one %-spec into fmtcpy. */ |
7469ef5d | 192 | string = fmtcpy; |
24f98398 | 193 | *string++ = '%'; |
94dcfacf | 194 | while (fmt < format_end) |
24f98398 JA |
195 | { |
196 | *string++ = *fmt; | |
be65c2f4 PE |
197 | if ('0' <= *fmt && *fmt <= '9') |
198 | { | |
199 | /* Get an idea of how much space we might need. | |
200 | This might be a field width or a precision; e.g. | |
201 | %1.1000f and %1000.1f both might need 1000+ bytes. | |
202 | Parse the width or precision, checking for overflow. */ | |
c2d1e36d | 203 | ptrdiff_t n = *fmt - '0'; |
ad5f9eea | 204 | while (fmt + 1 < format_end |
94dcfacf | 205 | && '0' <= fmt[1] && fmt[1] <= '9') |
be65c2f4 | 206 | { |
c2d1e36d | 207 | /* Avoid ptrdiff_t, size_t, and int overflow, as |
ca2d6274 PE |
208 | many sprintfs mishandle widths greater than INT_MAX. |
209 | This test is simple but slightly conservative: e.g., | |
210 | (INT_MAX - INT_MAX % 10) is reported as an overflow | |
211 | even when it's not. */ | |
c2d1e36d | 212 | if (n >= min (INT_MAX, min (PTRDIFF_MAX, SIZE_MAX)) / 10) |
be65c2f4 | 213 | error ("Format width or precision too large"); |
26898943 | 214 | n = n * 10 + fmt[1] - '0'; |
be65c2f4 PE |
215 | *string++ = *++fmt; |
216 | } | |
217 | ||
218 | if (size_bound < n) | |
219 | size_bound = n; | |
220 | } | |
ad5f9eea PE |
221 | else if (! (*fmt == '-' || *fmt == ' ' || *fmt == '.' |
222 | || *fmt == '+')) | |
24f98398 JA |
223 | break; |
224 | fmt++; | |
225 | } | |
ad5f9eea | 226 | |
62f19c19 PE |
227 | /* Check for the length modifiers in textual length order, so |
228 | that longer modifiers override shorter ones. */ | |
229 | for (mlen = 1; mlen <= maxmlen; mlen++) | |
ad5f9eea | 230 | { |
62f19c19 PE |
231 | if (format_end - fmt < mlen) |
232 | break; | |
233 | if (mlen == 1 && *fmt == 'l') | |
234 | length_modifier = long_modifier; | |
235 | if (mlen == pDlen && memcmp (fmt, pD, pDlen) == 0) | |
236 | length_modifier = pD_modifier; | |
237 | if (mlen == pIlen && memcmp (fmt, pI, pIlen) == 0) | |
238 | length_modifier = pI_modifier; | |
239 | if (mlen == pMlen && memcmp (fmt, pMd, pMlen) == 0) | |
240 | length_modifier = pM_modifier; | |
ad5f9eea | 241 | } |
62f19c19 PE |
242 | |
243 | mlen = modifier_len[length_modifier]; | |
244 | memcpy (string, fmt + 1, mlen); | |
245 | string += mlen; | |
246 | fmt += mlen; | |
24f98398 | 247 | *string = 0; |
03383aaf | 248 | |
be65c2f4 PE |
249 | /* Make the size bound large enough to handle floating point formats |
250 | with large numbers. */ | |
c2d1e36d | 251 | if (size_bound > min (PTRDIFF_MAX, SIZE_MAX) - DBL_MAX_10_EXP - 50) |
be65c2f4 | 252 | error ("Format width or precision too large"); |
01769a73 | 253 | size_bound += DBL_MAX_10_EXP + 50; |
6e951728 | 254 | |
f4c730d3 RS |
255 | /* Make sure we have that much. */ |
256 | if (size_bound > size_allocated) | |
257 | { | |
258 | if (big_buffer) | |
94dcfacf EZ |
259 | xfree (big_buffer); |
260 | big_buffer = (char *) xmalloc (size_bound); | |
f4c730d3 RS |
261 | sprintf_buffer = big_buffer; |
262 | size_allocated = size_bound; | |
263 | } | |
24f98398 JA |
264 | minlen = 0; |
265 | switch (*fmt++) | |
266 | { | |
267 | default: | |
ad5f9eea | 268 | error ("Invalid format operation %s", fmtcpy); |
24f98398 JA |
269 | |
270 | /* case 'b': */ | |
e6c3da20 | 271 | case 'l': |
24f98398 | 272 | case 'd': |
62f19c19 PE |
273 | switch (length_modifier) |
274 | { | |
275 | case no_modifier: | |
e810457d | 276 | { |
62f19c19 PE |
277 | int v = va_arg (ap, int); |
278 | sprintf (sprintf_buffer, fmtcpy, v); | |
e810457d | 279 | } |
62f19c19 PE |
280 | break; |
281 | case long_modifier: | |
e6c3da20 | 282 | { |
62f19c19 PE |
283 | long v = va_arg (ap, long); |
284 | sprintf (sprintf_buffer, fmtcpy, v); | |
e6c3da20 | 285 | } |
62f19c19 PE |
286 | break; |
287 | case pD_modifier: | |
288 | signed_pD_modifier: | |
e6c3da20 | 289 | { |
62f19c19 PE |
290 | ptrdiff_t v = va_arg (ap, ptrdiff_t); |
291 | sprintf (sprintf_buffer, fmtcpy, v); | |
e6c3da20 | 292 | } |
62f19c19 PE |
293 | break; |
294 | case pI_modifier: | |
295 | { | |
296 | EMACS_INT v = va_arg (ap, EMACS_INT); | |
297 | sprintf (sprintf_buffer, fmtcpy, v); | |
298 | } | |
299 | break; | |
300 | case pM_modifier: | |
301 | { | |
302 | intmax_t v = va_arg (ap, intmax_t); | |
303 | sprintf (sprintf_buffer, fmtcpy, v); | |
304 | } | |
305 | break; | |
306 | } | |
307 | /* Now copy into final output, truncating as necessary. */ | |
308 | string = sprintf_buffer; | |
309 | goto doit; | |
e6c3da20 | 310 | |
24f98398 JA |
311 | case 'o': |
312 | case 'x': | |
62f19c19 PE |
313 | switch (length_modifier) |
314 | { | |
315 | case no_modifier: | |
e810457d | 316 | { |
62f19c19 PE |
317 | unsigned v = va_arg (ap, unsigned); |
318 | sprintf (sprintf_buffer, fmtcpy, v); | |
e810457d | 319 | } |
62f19c19 PE |
320 | break; |
321 | case long_modifier: | |
e6c3da20 | 322 | { |
62f19c19 PE |
323 | unsigned long v = va_arg (ap, unsigned long); |
324 | sprintf (sprintf_buffer, fmtcpy, v); | |
e6c3da20 | 325 | } |
62f19c19 PE |
326 | break; |
327 | case pD_modifier: | |
328 | goto signed_pD_modifier; | |
329 | case pI_modifier: | |
e6c3da20 | 330 | { |
62f19c19 PE |
331 | EMACS_UINT v = va_arg (ap, EMACS_UINT); |
332 | sprintf (sprintf_buffer, fmtcpy, v); | |
e6c3da20 | 333 | } |
62f19c19 PE |
334 | break; |
335 | case pM_modifier: | |
336 | { | |
337 | uintmax_t v = va_arg (ap, uintmax_t); | |
338 | sprintf (sprintf_buffer, fmtcpy, v); | |
339 | } | |
340 | break; | |
341 | } | |
342 | /* Now copy into final output, truncating as necessary. */ | |
343 | string = sprintf_buffer; | |
344 | goto doit; | |
24f98398 | 345 | |
f4c730d3 RS |
346 | case 'f': |
347 | case 'e': | |
348 | case 'g': | |
349 | { | |
6a8033e1 KR |
350 | double d = va_arg(ap, double); |
351 | sprintf (sprintf_buffer, fmtcpy, d); | |
e6c3da20 | 352 | /* Now copy into final output, truncating as necessary. */ |
7469ef5d | 353 | string = sprintf_buffer; |
f4c730d3 RS |
354 | goto doit; |
355 | } | |
356 | ||
24f98398 JA |
357 | case 'S': |
358 | string[-1] = 's'; | |
359 | case 's': | |
24f98398 JA |
360 | if (fmtcpy[1] != 's') |
361 | minlen = atoi (&fmtcpy[1]); | |
7469ef5d | 362 | string = va_arg (ap, char *); |
e267324c | 363 | tem = strlen (string); |
c9d624c6 | 364 | if (STRING_BYTES_BOUND < tem) |
e6c3da20 | 365 | error ("String for %%s or %%S format is too long"); |
a0ca925c | 366 | width = strwidth (string, tem); |
1513af9e RS |
367 | goto doit1; |
368 | ||
24f98398 JA |
369 | /* Copy string into final output, truncating if no room. */ |
370 | doit: | |
a0ca925c | 371 | /* Coming here means STRING contains ASCII only. */ |
e6c3da20 | 372 | tem = strlen (string); |
c9d624c6 | 373 | if (STRING_BYTES_BOUND < tem) |
e6c3da20 EZ |
374 | error ("Format width or precision too large"); |
375 | width = tem; | |
35a65fce | 376 | doit1: |
a0ca925c KH |
377 | /* We have already calculated: |
378 | TEM -- length of STRING, | |
379 | WIDTH -- columns occupied by STRING when displayed, and | |
380 | MINLEN -- minimum columns of the output. */ | |
24f98398 JA |
381 | if (minlen > 0) |
382 | { | |
a0ca925c | 383 | while (minlen > width && bufsize > 0) |
24f98398 JA |
384 | { |
385 | *bufptr++ = ' '; | |
386 | bufsize--; | |
387 | minlen--; | |
388 | } | |
389 | minlen = 0; | |
390 | } | |
391 | if (tem > bufsize) | |
a0ca925c KH |
392 | { |
393 | /* Truncate the string at character boundary. */ | |
394 | tem = bufsize; | |
a50545d9 | 395 | while (!CHAR_HEAD_P (string[tem - 1])) tem--; |
afda1437 EZ |
396 | /* If the multibyte sequence of this character is |
397 | too long for the space we have left in the | |
398 | buffer, truncate before it. */ | |
399 | if (tem > 0 | |
400 | && BYTES_BY_CHAR_HEAD (string[tem - 1]) > bufsize) | |
401 | tem--; | |
402 | if (tem > 0) | |
403 | memcpy (bufptr, string, tem); | |
404 | bufptr[tem] = 0; | |
405 | /* Trigger exit from the loop, but make sure we | |
406 | return to the caller a value which will indicate | |
407 | that the buffer was too small. */ | |
408 | bufptr += bufsize; | |
409 | bufsize = 0; | |
410 | continue; | |
a0ca925c KH |
411 | } |
412 | else | |
72af86bd | 413 | memcpy (bufptr, string, tem); |
24f98398 JA |
414 | bufptr += tem; |
415 | bufsize -= tem; | |
416 | if (minlen < 0) | |
417 | { | |
a0ca925c | 418 | while (minlen < - width && bufsize > 0) |
24f98398 JA |
419 | { |
420 | *bufptr++ = ' '; | |
421 | bufsize--; | |
422 | minlen++; | |
423 | } | |
424 | minlen = 0; | |
425 | } | |
426 | continue; | |
427 | ||
428 | case 'c': | |
6a8033e1 | 429 | { |
e6c3da20 EZ |
430 | int chr = va_arg(ap, int); |
431 | tem = CHAR_STRING (chr, (unsigned char *) charbuf); | |
6a8033e1 KR |
432 | string = charbuf; |
433 | string[tem] = 0; | |
434 | width = strwidth (string, tem); | |
435 | if (fmtcpy[1] != 'c') | |
436 | minlen = atoi (&fmtcpy[1]); | |
437 | goto doit1; | |
438 | } | |
24f98398 JA |
439 | |
440 | case '%': | |
441 | fmt--; /* Drop thru and this % will be treated as normal */ | |
442 | } | |
443 | } | |
a0ca925c KH |
444 | |
445 | { | |
446 | /* Just some character; Copy it if the whole multi-byte form | |
447 | fit in the buffer. */ | |
448 | char *save_bufptr = bufptr; | |
449 | ||
450 | do { *bufptr++ = *fmt++; } | |
94dcfacf | 451 | while (fmt < format_end && --bufsize > 0 && !CHAR_HEAD_P (*fmt)); |
a50545d9 | 452 | if (!CHAR_HEAD_P (*fmt)) |
a0ca925c | 453 | { |
d178f871 EZ |
454 | /* Truncate, but return value that will signal to caller |
455 | that the buffer was too small. */ | |
456 | *save_bufptr = 0; | |
a0ca925c KH |
457 | break; |
458 | } | |
459 | } | |
24f98398 JA |
460 | }; |
461 | ||
f4c730d3 | 462 | /* If we had to malloc something, free it. */ |
70fdbb46 | 463 | xfree (big_buffer); |
f4c730d3 | 464 | |
e6c3da20 | 465 | *bufptr = 0; /* Make sure our string ends with a '\0' */ |
825cd63c EZ |
466 | |
467 | SAFE_FREE (); | |
24f98398 JA |
468 | return bufptr - buffer; |
469 | } | |
62f19c19 PE |
470 | |
471 | /* Format to an unbounded buffer BUF. This is like sprintf, except it | |
472 | is not limited to returning an 'int' so it doesn't have a silly 2 | |
473 | GiB limit on typical 64-bit hosts. However, it is limited to the | |
474 | Emacs-style formats that doprnt supports. | |
475 | ||
476 | Return the number of bytes put into BUF, excluding the terminating | |
477 | '\0'. */ | |
478 | ptrdiff_t | |
479 | esprintf (char *buf, char const *format, ...) | |
480 | { | |
481 | ptrdiff_t nbytes; | |
482 | va_list ap; | |
483 | va_start (ap, format); | |
484 | nbytes = doprnt (buf, TYPE_MAXIMUM (ptrdiff_t), format, 0, ap); | |
485 | va_end (ap); | |
486 | return nbytes; | |
487 | } | |
488 | ||
62f19c19 PE |
489 | /* Format to buffer *BUF of positive size *BUFSIZE, reallocating *BUF |
490 | and updating *BUFSIZE if the buffer is too small, and otherwise | |
491 | behaving line esprintf. When reallocating, free *BUF unless it is | |
492 | equal to NONHEAPBUF, and if BUFSIZE_MAX is nonnegative then signal | |
493 | memory exhaustion instead of growing the buffer size past | |
494 | BUFSIZE_MAX. */ | |
495 | ptrdiff_t | |
496 | exprintf (char **buf, ptrdiff_t *bufsize, | |
497 | char const *nonheapbuf, ptrdiff_t bufsize_max, | |
498 | char const *format, ...) | |
499 | { | |
500 | ptrdiff_t nbytes; | |
501 | va_list ap; | |
502 | va_start (ap, format); | |
503 | nbytes = evxprintf (buf, bufsize, nonheapbuf, bufsize_max, format, ap); | |
504 | va_end (ap); | |
505 | return nbytes; | |
506 | } | |
507 | ||
508 | /* Act like exprintf, except take a va_list. */ | |
509 | ptrdiff_t | |
510 | evxprintf (char **buf, ptrdiff_t *bufsize, | |
511 | char const *nonheapbuf, ptrdiff_t bufsize_max, | |
512 | char const *format, va_list ap) | |
513 | { | |
514 | for (;;) | |
515 | { | |
516 | ptrdiff_t nbytes; | |
517 | va_list ap_copy; | |
518 | va_copy (ap_copy, ap); | |
519 | nbytes = doprnt (*buf, *bufsize, format, 0, ap_copy); | |
520 | va_end (ap_copy); | |
521 | if (nbytes < *bufsize - 1) | |
522 | return nbytes; | |
523 | if (*buf != nonheapbuf) | |
524 | xfree (*buf); | |
525 | *buf = xpalloc (NULL, bufsize, 1, bufsize_max, 1); | |
526 | } | |
527 | } |