appl/ftp/common/buffer.c

   1 /*
   2  * Copyright (c) 1995, 1996, 1997 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. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by the Kungliga Tekniska
  20  *      Högskolan and its contributors.
  21  *
  22  * 4. Neither the name of the Institute nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  */
  38
  39 #include "common.h"
  40 #include <stdio.h>
  41 #include "roken.h"
  42
  43 RCSID("$Id$");
  44
  45 /*
  46  * Allocate a buffer enough to handle st->st_blksize, if
  47  * there is such a field, otherwise BUFSIZ.
  48  */
  49
  50 void *
  51 alloc_buffer (void *oldbuf, size_t *sz, struct stat *st)
  52 {
  53     size_t new_sz;
  54
  55     new_sz = BUFSIZ;
  56 #ifdef HAVE_ST_BLKSIZE
  57     if (st)
  58         new_sz = max(BUFSIZ, st->st_blksize);
  59 #endif
  60     if(new_sz > *sz) {
  61         if (oldbuf)
  62             free (oldbuf);
  63         oldbuf = malloc (new_sz);
  64         if (oldbuf == NULL) {
  65             warn ("malloc");
  66             *sz = 0;
  67             return NULL;
  68         }
  69         *sz = new_sz;
  70     }
  71     return oldbuf;
  72 }
  73