mirror of
https://gcc.gnu.org/git/gcc.git
synced 2024-11-30 07:14:09 +08:00
52dd322420
* vsnprintf.c (vsnprintf): Don't pad string with extra nulls. (main): Test that we don't write too much data. From-SVN: r65955
154 lines
4.2 KiB
C
154 lines
4.2 KiB
C
/* Implement the vsnprintf function.
|
|
Copyright (C) 2003 Free Software Foundation, Inc.
|
|
Written by Kaveh R. Ghazi <ghazi@caip.rutgers.edu>.
|
|
|
|
This file is part of the libiberty library. This library is free
|
|
software; you can redistribute it and/or modify it under the
|
|
terms of the GNU General Public License as published by the
|
|
Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
This library 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU CC; see the file COPYING. If not, write to
|
|
the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
As a special exception, if you link this library with files
|
|
compiled with a GNU compiler to produce an executable, this does not cause
|
|
the resulting executable to be covered by the GNU General Public License.
|
|
This exception does not however invalidate any other reasons why
|
|
the executable file might be covered by the GNU General Public License. */
|
|
|
|
/*
|
|
|
|
@deftypefn Supplemental int vsnprintf (char *@var{buf}, size_t @var{n}, const char *@var{format}, va_list @var{ap})
|
|
|
|
This function is similar to vsprintf, but it will print at most
|
|
@var{n} characters. On error the return value is -1, otherwise it
|
|
returns the number of characters that would have been printed had
|
|
@var{n} been sufficiently large, regardless of the actual value of
|
|
@var{n}. Note some pre-C99 system libraries do not implement this
|
|
correctly so users cannot generally rely on the return value if the
|
|
system version of this function is used.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
#include "config.h"
|
|
#include "ansidecl.h"
|
|
|
|
#ifdef ANSI_PROTOTYPES
|
|
#include <stdarg.h>
|
|
#else
|
|
#include <varargs.h>
|
|
#endif
|
|
#ifdef HAVE_STRING_H
|
|
#include <string.h>
|
|
#endif
|
|
#ifdef HAVE_STDLIB_H
|
|
#include <stdlib.h>
|
|
#endif
|
|
|
|
#include "libiberty.h"
|
|
|
|
/* This implementation relies on a working vasprintf. */
|
|
int
|
|
vsnprintf (s, n, format, ap)
|
|
char * s;
|
|
size_t n;
|
|
const char *format;
|
|
va_list ap;
|
|
{
|
|
char *buf = 0;
|
|
int result = vasprintf (&buf, format, ap);
|
|
|
|
if (!buf)
|
|
return -1;
|
|
if (result < 0)
|
|
{
|
|
free (buf);
|
|
return -1;
|
|
}
|
|
|
|
result = strlen (buf);
|
|
if (n > 0)
|
|
{
|
|
if ((long) n > result)
|
|
memcpy (s, buf, result+1);
|
|
else
|
|
{
|
|
memcpy (s, buf, n-1);
|
|
s[n - 1] = 0;
|
|
}
|
|
}
|
|
free (buf);
|
|
return result;
|
|
}
|
|
|
|
#ifdef TEST
|
|
/* Set the buffer to a known state. */
|
|
#define CLEAR(BUF) do { memset ((BUF), 'X', sizeof (BUF)); (BUF)[14] = '\0'; } while (0)
|
|
/* For assertions. */
|
|
#define VERIFY(P) do { if (!(P)) abort(); } while (0)
|
|
|
|
static int ATTRIBUTE_PRINTF_3
|
|
checkit VPARAMS ((char *s, size_t n, const char *format, ...))
|
|
{
|
|
int result;
|
|
VA_OPEN (ap, format);
|
|
VA_FIXEDARG (ap, char *, s);
|
|
VA_FIXEDARG (ap, size_t, n);
|
|
VA_FIXEDARG (ap, const char *, format);
|
|
result = vsnprintf (s, n, format, ap);
|
|
VA_CLOSE (ap);
|
|
return result;
|
|
}
|
|
|
|
extern int main PARAMS ((void));
|
|
int
|
|
main ()
|
|
{
|
|
char buf[128];
|
|
int status;
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 10, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "foobar:9\0XXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 9, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "foobar:9\0XXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 8, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "foobar:\0XXXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 7, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "foobar\0XXXXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 6, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "fooba\0XXXXXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 2, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "f\0XXXXXXXXXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 1, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "\0XXXXXXXXXXXXX\0", 15) == 0);
|
|
|
|
CLEAR (buf);
|
|
status = checkit (buf, 0, "%s:%d", "foobar", 9);
|
|
VERIFY (status==8 && memcmp (buf, "XXXXXXXXXXXXXX\0", 15) == 0);
|
|
|
|
return 0;
|
|
}
|
|
#endif /* TEST */
|