1  /*
 2   * Copyright (c) 1995-2000 Kungliga Tekniska Högskolan
 3   * (Royal Institute of Technology, Stockholm, Sweden).
 4   * All rights reserved.
 5   *
 6   * Redistribution and use in source and binary forms, with or without
 7   * modification, are permitted provided that the following conditions
 8   * are met:
 9   *
10   * 1. Redistributions of source code must retain the above copyright
11   *    notice, this list of conditions and the following disclaimer.
12   *
13   * 2. Redistributions in binary form must reproduce the above copyright
14   *    notice, this list of conditions and the following disclaimer in the
15   *    documentation and/or other materials provided with the distribution.
16   *
17   * 3. Neither the name of the Institute nor the names of its contributors
18   *    may be used to endorse or promote products derived from this software
19   *    without specific prior written permission.
20   *
21   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24   * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31   * SUCH DAMAGE.
32   */
33  
34  #include "common.h"
35  #include <stdio.h>
36  #include <err.h>
37  #include "roken.h"
38  
39  RCSID("$Id$");
40  
41  /*
42   * Allocate a buffer enough to handle st->st_blksize, if
43   * there is such a field, otherwise BUFSIZ.
44   */
45  
46  void *
47  alloc_buffer (void *oldbuf, size_t *sz, struct stat *st)
48  {
49      size_t new_sz;
50  
51      new_sz = BUFSIZ;
52  #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
53      if (st)
54  	new_sz = max(BUFSIZ, st->st_blksize);
55  #endif
56      if(new_sz > *sz) {
57  	if (oldbuf)
58  	    free (oldbuf);
59  	oldbuf = malloc (new_sz);
60  	if (oldbuf == NULL) {
61  	    warn ("malloc");
62  	    *sz = 0;
63  	    return NULL;
64  	}
65  	*sz = new_sz;
66      }
67      return oldbuf;
68  }
69