usr/src/cmd/mailwrapper/fgetln.c

   1 /* $Id$ */
   2 /*      $NetBSD: fgetln.c,v 1.3 2007/08/07 02:06:58 lukem Exp $ */
   3
   4 /*
   5  * Copyright (c) 1998 The NetBSD Foundation, Inc.
   6  * All rights reserved.
   7  *
   8  * This code is derived from software contributed to The NetBSD Foundation
   9  * by Christos Zoulas.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of The NetBSD Foundation nor the names of its
  20  *    contributors may be used to endorse or promote products derived
  21  *    from this software without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  33  * POSSIBILITY OF SUCH DAMAGE.
  34  */
  35
  36 #include <sys/types.h>
  37
  38 #include <errno.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 char *
  44 fgetln(FILE *fp, size_t *len)
  45 {
  46         static char *buf = NULL;
  47         static size_t bufsiz = 0;
  48         char *ptr;
  49
  50
  51         if (buf == NULL) {
  52                 bufsiz = BUFSIZ;
  53                 if ((buf = malloc(bufsiz)) == NULL)
  54                         return (NULL);
  55         }
  56
  57         if (fgets(buf, bufsiz, fp) == NULL)
  58                 return (NULL);
  59
  60         *len = 0;
  61         while ((ptr = strchr(&buf[*len], '\n')) == NULL) {
  62                 size_t nbufsiz = bufsiz + BUFSIZ;
  63                 char *nbuf = realloc(buf, nbufsiz);
  64
  65                 if (nbuf == NULL) {
  66                         int oerrno = errno;
  67                         free(buf);
  68                         errno = oerrno;
  69                         buf = NULL;
  70                         return (NULL);
  71                 } else
  72                         buf = nbuf;
  73
  74                 *len = bufsiz;
  75                 if (fgets(&buf[bufsiz], BUFSIZ, fp) == NULL)
  76                         return (buf);
  77
  78                 bufsiz = nbufsiz;
  79         }
  80
  81         *len = (ptr - buf) + 1;
  82         return (buf);
  83 }