1 | /* vsprintf with automatic memory allocation. |
2 | Copyright (C) 2002-2004, 2007-2012 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 Lesser General Public License as published by |
6 | the Free Software Foundation; either version 2.1, 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 Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public License along |
15 | with this program; if not, see <http://www.gnu.org/licenses/>. */ |
16 | |
17 | #ifndef _VASNPRINTF_H |
18 | #define _VASNPRINTF_H |
19 | |
20 | /* Get va_list. */ |
21 | #include <stdarg.h> |
22 | |
23 | /* Get size_t. */ |
24 | #include <stddef.h> |
25 | |
26 | /* The __attribute__ feature is available in gcc versions 2.5 and later. |
27 | The __-protected variants of the attributes 'format' and 'printf' are |
28 | accepted by gcc versions 2.6.4 (effectively 2.7) and later. |
29 | We enable _GL_ATTRIBUTE_FORMAT only if these are supported too, because |
30 | gnulib and libintl do '#define printf __printf__' when they override |
31 | the 'printf' function. */ |
32 | #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7) |
33 | # define _GL_ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec)) |
34 | #else |
35 | # define _GL_ATTRIBUTE_FORMAT(spec) /* empty */ |
36 | #endif |
37 | |
38 | #ifdef __cplusplus |
39 | extern "C" { |
40 | #endif |
41 | |
42 | /* Write formatted output to a string dynamically allocated with malloc(). |
43 | You can pass a preallocated buffer for the result in RESULTBUF and its |
44 | size in *LENGTHP; otherwise you pass RESULTBUF = NULL. |
45 | If successful, return the address of the string (this may be = RESULTBUF |
46 | if no dynamic memory allocation was necessary) and set *LENGTHP to the |
47 | number of resulting bytes, excluding the trailing NUL. Upon error, set |
48 | errno and return NULL. |
49 | |
50 | When dynamic memory allocation occurs, the preallocated buffer is left |
51 | alone (with possibly modified contents). This makes it possible to use |
52 | a statically allocated or stack-allocated buffer, like this: |
53 | |
54 | char buf[100]; |
55 | size_t len = sizeof (buf); |
56 | char *output = vasnprintf (buf, &len, format, args); |
57 | if (output == NULL) |
58 | ... error handling ...; |
59 | else |
60 | { |
61 | ... use the output string ...; |
62 | if (output != buf) |
63 | free (output); |
64 | } |
65 | */ |
66 | #if REPLACE_VASNPRINTF |
67 | # define asnprintf rpl_asnprintf |
68 | # define vasnprintf rpl_vasnprintf |
69 | #endif |
70 | extern char * asnprintf (char *resultbuf, size_t *lengthp, const char *format, ...) |
71 | _GL_ATTRIBUTE_FORMAT ((__printf__, 3, 4)); |
72 | extern char * vasnprintf (char *resultbuf, size_t *lengthp, const char *format, va_list args) |
73 | _GL_ATTRIBUTE_FORMAT ((__printf__, 3, 0)); |
74 | |
75 | #ifdef __cplusplus |
76 | } |
77 | #endif |
78 | |
79 | #endif /* _VASNPRINTF_H */ |
80 | |