contrib/file/src/getline.c

   1 /*      $NetBSD: getline.c,v 1.2 2014/09/16 17:23:50 christos Exp $     */
   2
   3 /*-
   4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Christos Zoulas.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include "file.h"
  33 #if !HAVE_GETLINE
  34 #include <stdlib.h>
  35 #include <stdio.h>
  36 #include <unistd.h>
  37 #include <errno.h>
  38 #include <string.h>
  39
  40 public ssize_t
  41 getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp)
  42 {
  43         char *ptr, *eptr;
  44
  45
  46         if (*buf == NULL || *bufsiz == 0) {
  47                 *bufsiz = BUFSIZ;
  48                 if ((*buf = malloc(*bufsiz)) == NULL)
  49                         return -1;
  50         }
  51
  52         for (ptr = *buf, eptr = *buf + *bufsiz;;) {
  53                 int c = fgetc(fp);
  54                 if (c == -1) {
  55                         if (feof(fp)) {
  56                                 ssize_t diff = (ssize_t)(ptr - *buf);
  57                                 if (diff != 0) {
  58                                         *ptr = '\0';
  59                                         return diff;
  60                                 }
  61                         }
  62                         return -1;
  63                 }
  64                 *ptr++ = c;
  65                 if (c == delimiter) {
  66                         *ptr = '\0';
  67                         return ptr - *buf;
  68                 }
  69                 if (ptr + 2 >= eptr) {
  70                         char *nbuf;
  71                         size_t nbufsiz = *bufsiz * 2;
  72                         ssize_t d = ptr - *buf;
  73                         if ((nbuf = realloc(*buf, nbufsiz)) == NULL)
  74                                 return -1;
  75                         *buf = nbuf;
  76                         *bufsiz = nbufsiz;
  77                         eptr = nbuf + nbufsiz;
  78                         ptr = nbuf + d;
  79                 }
  80         }
  81 }
  82
  83 public ssize_t
  84 getline(char **buf, size_t *bufsiz, FILE *fp)
  85 {
  86         return getdelim(buf, bufsiz, '\n', fp);
  87 }
  88
  89 #endif
  90
  91 #ifdef TEST
  92 int
  93 main(int argc, char *argv[])
  94 {
  95         char *p = NULL;
  96         ssize_t len;
  97         size_t n = 0;
  98
  99         while ((len = getline(&p, &n, stdin)) != -1)
 100                 (void)printf("%" SIZE_T_FORMAT "d %s", len, p);
 101         free(p);
 102         return 0;
 103 }
 104 #endif