diff options
Diffstat (limited to 'newlib/libc/stdio/vswprintf.c')
| -rw-r--r-- | newlib/libc/stdio/vswprintf.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/newlib/libc/stdio/vswprintf.c b/newlib/libc/stdio/vswprintf.c index aebb20a00..2d9096c15 100644 --- a/newlib/libc/stdio/vswprintf.c +++ b/newlib/libc/stdio/vswprintf.c @@ -27,6 +27,7 @@ static char sccsid[] = "%W% (Berkeley) %G%"; #include <limits.h> #include <stdarg.h> #include <errno.h> + #include "local.h" int @@ -42,7 +43,7 @@ _DEFUN(_vswprintf_r, (ptr, str, size, fmt, ap), if (size > INT_MAX / sizeof (wchar_t)) { - ptr->_errno = EOVERFLOW; + ptr->_errno = EOVERFLOW; /* POSIX extension */ return EOF; } f._flags = __SWR | __SSTR; @@ -50,10 +51,19 @@ _DEFUN(_vswprintf_r, (ptr, str, size, fmt, ap), f._bf._size = f._w = (size > 0 ? (size - 1) * sizeof (wchar_t) : 0); f._file = -1; /* No file. */ ret = _svfwprintf_r (ptr, &f, fmt, ap); - if (ret < EOF) - ptr->_errno = EOVERFLOW; - if (size > 0) - *f._p = 0; + /* _svfwprintf_r() does not put in a terminating NUL, so add one if + * appropriate, which is whenever size is > 0. _svfwprintf_r() stops + * after n-1, so always just put at the end. */ + if (size > 0) { + *(wchar_t *)f._p = L'\0'; /* terminate the string */ + } + if(ret >= size) { + /* _svfwprintf_r() returns how many wide characters it would have printed + * if there were enough space. Return an error if too big to fit in str, + * unlike snprintf, which returns the size needed. */ + ptr->_errno = EOVERFLOW; /* POSIX extension */ + ret = -1; + } return ret; } |