appl/ftp/common/buffer.c

   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