diff options
Diffstat (limited to 'src/asprintf.c')
-rw-r--r-- | src/asprintf.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/src/asprintf.c b/src/asprintf.c new file mode 100644 index 0000000..d493fcb --- /dev/null +++ b/src/asprintf.c | |||
@@ -0,0 +1,85 @@ | |||
1 | /* grecs - Gray's Extensible Configuration System | ||
2 | Copyright (C) 2007-2011 Sergey Poznyakoff | ||
3 | |||
4 | Grecs is free software; you can redistribute it and/or modify it | ||
5 | under the terms of the GNU General Public License as published by the | ||
6 | Free Software Foundation; either version 3 of the License, or (at your | ||
7 | option) any later version. | ||
8 | |||
9 | Grecs 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 Grecs. If not, see <http://www.gnu.org/licenses/>. */ | ||
16 | |||
17 | #ifdef HAVE_CONFIG_H | ||
18 | # include <config.h> | ||
19 | #endif | ||
20 | #include <stdlib.h> | ||
21 | #include <string.h> | ||
22 | #include <errno.h> | ||
23 | #include "grecs.h" | ||
24 | |||
25 | int | ||
26 | grecs_vasprintf(char **pbuf, size_t *psize, const char *fmt, va_list ap) | ||
27 | { | ||
28 | char *buf = *pbuf; | ||
29 | size_t buflen = *psize; | ||
30 | int rc = 0; | ||
31 | |||
32 | if (!buf) { | ||
33 | if (buflen == 0) | ||
34 | buflen = 512; /* Initial allocation */ | ||
35 | |||
36 | buf = calloc(1, buflen); | ||
37 | if (buf == NULL) | ||
38 | return ENOMEM; | ||
39 | } | ||
40 | |||
41 | for (;;) { | ||
42 | ssize_t n = vsnprintf(buf, buflen, fmt, ap); | ||
43 | if (n < 0 || n >= buflen || !memchr(buf, '\0', n + 1)) { | ||
44 | char *newbuf; | ||
45 | size_t newlen = buflen * 2; | ||
46 | if (newlen < buflen) { | ||
47 | rc = ENOMEM; | ||
48 | break; | ||
49 | } | ||
50 | newbuf = realloc(buf, newlen); | ||
51 | if (newbuf == NULL) { | ||
52 | rc = ENOMEM; | ||
53 | break; | ||
54 | } | ||
55 | buflen = newlen; | ||
56 | buf = newbuf; | ||
57 | } else | ||
58 | break; | ||
59 | } | ||
60 | |||
61 | if (rc) { | ||
62 | if (!*pbuf) { | ||
63 | /* We made first allocation, now free it */ | ||
64 | free(buf); | ||
65 | buf = NULL; | ||
66 | buflen = 0; | ||
67 | } | ||
68 | } | ||
69 | |||
70 | *pbuf = buf; | ||
71 | *psize = buflen; | ||
72 | return rc; | ||
73 | } | ||
74 | |||
75 | int | ||
76 | grecs_asprintf(char **pbuf, size_t *psize, const char *fmt, ...) | ||
77 | { | ||
78 | int rc; | ||
79 | va_list ap; | ||
80 | |||
81 | va_start(ap, fmt); | ||
82 | rc = grecs_vasprintf(pbuf, psize, fmt, ap); | ||
83 | va_end(ap); | ||
84 | return rc; | ||
85 | } | ||