freebsd-dev/contrib/sendmail/libsm/vasprintf.c
2004-08-01 01:04:57 +00:00

105 lines
2.9 KiB
C

/*
* Copyright (c) 2000-2001 Sendmail, Inc. and its suppliers.
* All rights reserved.
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the sendmail distribution.
*/
/*
* Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND TODD C. MILLER DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL TODD C. MILLER BE LIABLE
* FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sm/gen.h>
SM_RCSID("@(#)$Id: vasprintf.c,v 1.27 2003/06/03 02:14:24 ca Exp $")
#include <stdlib.h>
#include <errno.h>
#include <sm/io.h>
#include <sm/heap.h>
#include "local.h"
/*
** SM_VASPRINTF -- printf to a dynamically allocated string
**
** Write 'printf' output to a dynamically allocated string
** buffer which is returned to the caller.
**
** Parameters:
** str -- *str receives a pointer to the allocated string
** fmt -- format directives for printing
** ap -- variable argument list
**
** Results:
** On failure, set *str to NULL, set errno, and return -1.
**
** On success, set *str to a pointer to a nul-terminated
** string buffer containing printf output, and return the
** length of the string (not counting the nul).
*/
#define SM_VA_BUFSIZE 128
int
sm_vasprintf(str, fmt, ap)
char **str;
const char *fmt;
SM_VA_LOCAL_DECL
{
int ret;
SM_FILE_T fake;
unsigned char *base;
fake.sm_magic = SmFileMagic;
fake.f_timeout = SM_TIME_FOREVER;
fake.f_timeoutstate = SM_TIME_BLOCK;
fake.f_file = -1;
fake.f_flags = SMWR | SMSTR | SMALC;
fake.f_bf.smb_base = fake.f_p = (unsigned char *)sm_malloc(SM_VA_BUFSIZE);
if (fake.f_bf.smb_base == NULL)
goto err2;
fake.f_close = NULL;
fake.f_open = NULL;
fake.f_read = NULL;
fake.f_write = NULL;
fake.f_seek = NULL;
fake.f_setinfo = fake.f_getinfo = NULL;
fake.f_type = "sm_vasprintf:fake";
fake.f_bf.smb_size = fake.f_w = SM_VA_BUFSIZE - 1;
fake.f_timeout = SM_TIME_FOREVER;
ret = sm_io_vfprintf(&fake, SM_TIME_FOREVER, fmt, ap);
if (ret == -1)
goto err;
*fake.f_p = '\0';
/* use no more space than necessary */
base = (unsigned char *) sm_realloc(fake.f_bf.smb_base, ret + 1);
if (base == NULL)
goto err;
*str = (char *)base;
return ret;
err:
if (fake.f_bf.smb_base != NULL)
{
sm_free(fake.f_bf.smb_base);
fake.f_bf.smb_base = NULL;
}
err2:
*str = NULL;
errno = ENOMEM;
return -1;
}