111 lines
2.7 KiB
C
111 lines
2.7 KiB
C
/* vasprintf and asprintf with out-of-memory checking.
|
|
Copyright (C) 1999, 2002-2004, 2006-2022 Free Software Foundation, Inc.
|
|
|
|
This program 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 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
|
|
|
#include <config.h>
|
|
|
|
/* Specification. */
|
|
#include "xvasprintf.h"
|
|
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
|
|
#include "xalloc.h"
|
|
|
|
/* Checked size_t computations. */
|
|
#include "xsize.h"
|
|
|
|
static char *
|
|
xstrcat (size_t argcount, va_list args)
|
|
{
|
|
char *result;
|
|
va_list ap;
|
|
size_t totalsize;
|
|
size_t i;
|
|
char *p;
|
|
|
|
/* Determine the total size. */
|
|
totalsize = 0;
|
|
va_copy (ap, args);
|
|
for (i = argcount; i > 0; i--)
|
|
{
|
|
const char *next = va_arg (ap, const char *);
|
|
totalsize = xsum (totalsize, strlen (next));
|
|
}
|
|
va_end (ap);
|
|
|
|
/* Test for overflow in the summing pass above or in (totalsize + 1) below.
|
|
Also, don't return a string longer than INT_MAX, for consistency with
|
|
vasprintf(). */
|
|
if (totalsize == SIZE_MAX || totalsize > INT_MAX)
|
|
{
|
|
errno = EOVERFLOW;
|
|
return NULL;
|
|
}
|
|
|
|
/* Allocate and fill the result string. */
|
|
result = XNMALLOC (totalsize + 1, char);
|
|
p = result;
|
|
for (i = argcount; i > 0; i--)
|
|
{
|
|
const char *next = va_arg (args, const char *);
|
|
size_t len = strlen (next);
|
|
memcpy (p, next, len);
|
|
p += len;
|
|
}
|
|
*p = '\0';
|
|
|
|
return result;
|
|
}
|
|
|
|
char *
|
|
xvasprintf (const char *format, va_list args)
|
|
{
|
|
char *result;
|
|
|
|
/* Recognize the special case format = "%s...%s". It is a frequently used
|
|
idiom for string concatenation and needs to be fast. We don't want to
|
|
have a separate function xstrcat() for this purpose. */
|
|
{
|
|
size_t argcount = 0;
|
|
const char *f;
|
|
|
|
for (f = format;;)
|
|
{
|
|
if (*f == '\0')
|
|
/* Recognized the special case of string concatenation. */
|
|
return xstrcat (argcount, args);
|
|
if (*f != '%')
|
|
break;
|
|
f++;
|
|
if (*f != 's')
|
|
break;
|
|
f++;
|
|
argcount++;
|
|
}
|
|
}
|
|
|
|
if (vasprintf (&result, format, args) < 0)
|
|
{
|
|
if (errno == ENOMEM)
|
|
xalloc_die ();
|
|
return NULL;
|
|
}
|
|
|
|
return result;
|
|
}
|