diff options
author | Andreas Rottmann <a.rottmann@gmx.at> | 2009-09-14 12:32:44 +0200 |
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committer | Andreas Rottmann <a.rottmann@gmx.at> | 2009-09-14 12:32:44 +0200 |
commit | fa095a4504cbe668e4244547e2c141597bea4ecf (patch) | |
tree | 06135820a286ffec47804e75fbf8a147e92acd2e /lib/unistdio/u-vsprintf.h |
Imported Upstream version 0.9.1upstream/0.9.1
Diffstat (limited to 'lib/unistdio/u-vsprintf.h')
-rw-r--r-- | lib/unistdio/u-vsprintf.h | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/unistdio/u-vsprintf.h b/lib/unistdio/u-vsprintf.h new file mode 100644 index 00000000..36ebd9fa --- /dev/null +++ b/lib/unistdio/u-vsprintf.h @@ -0,0 +1,58 @@ +/* Formatted output to strings. + Copyright (C) 1999, 2002, 2006-2008 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#ifndef SIZE_MAX +# define SIZE_MAX ((size_t) -1) +#endif + +int +VSPRINTF (DCHAR_T *buf, const FCHAR_T *format, va_list args) +{ + /* Pass an infinite length. But note that *vasnprintf may fail if the buffer + argument is larger than INT_MAX (if that fits into a 'size_t' at all). + Also note that glibc's iconv fails with E2BIG when we pass a length that + is so large that buf + length wraps around, i.e. + (uintptr_t) (buf + length) < (uintptr_t) buf. */ + size_t length; + DCHAR_T *result; + + /* Set length = min (SIZE_MAX, INT_MAX, - (uintptr_t) buf - 1). */ + length = (SIZE_MAX < INT_MAX ? SIZE_MAX : INT_MAX); + if (length > (~ (uintptr_t) buf) / sizeof (DCHAR_T)) + length = (~ (uintptr_t) buf) / sizeof (DCHAR_T); + + result = VASNPRINTF (buf, &length, format, args); + if (result == NULL) + return -1; + + /* The infinite buffer size guarantees that the result is not malloc()ed. */ + if (result != buf) + { + /* length is near SIZE_MAX. */ + free (result); + errno = EOVERFLOW; + return -1; + } + + if (length > INT_MAX) + { + errno = EOVERFLOW; + return -1; + } + + /* Return the number of resulting units, excluding the trailing NUL. */ + return length; +} |