1 /* getdelim.c --- Implementation of replacement getdelim function.
2 Copyright (C) 1994, 1996, 1997, 1998, 2001, 2003, 2005 Free
3 Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or
6 modify it under the terms of the GNU General Public License as
7 published by the Free Software Foundation; either version 2, or (at
8 your option) any later version.
9
10 This program is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18 02110-1301, USA. */
19
20 /* Ported from glibc by Simon Josefsson. */
21
22 #ifdef HAVE_CONFIG_H
23 # include <config.h>
24 #endif
25
26 #include "getdelim.h"
27
28 #include <limits.h>
29 #include <stdlib.h>
30 #include <errno.h>
31
32 #ifndef SIZE_MAX
33 # define SIZE_MAX ((size_t) -1)
34 #endif
35 #ifndef SSIZE_MAX
36 # define SSIZE_MAX ((ssize_t) (SIZE_MAX / 2))
37 #endif
38 #if !HAVE_FLOCKFILE
39 # undef flockfile
40 # define flockfile(x) ((void) 0)
41 #endif
42 #if !HAVE_FUNLOCKFILE
43 # undef funlockfile
44 # define funlockfile(x) ((void) 0)
45 #endif
46
47 /* Read up to (and including) a DELIMITER from FP into *LINEPTR (and
48 NUL-terminate it). *LINEPTR is a pointer returned from malloc (or
49 NULL), pointing to *N characters of space. It is realloc'ed as
50 necessary. Returns the number of characters read (not including
51 the null terminator), or -1 on error or EOF. */
52
53 ssize_t
getdelim(char ** lineptr,size_t * n,int delimiter,FILE * fp)54 getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
55 {
56 ssize_t result;
57 size_t cur_len = 0;
58
59 if (lineptr == NULL || n == NULL || fp == NULL)
60 {
61 errno = EINVAL;
62 return -1;
63 }
64
65 flockfile (fp);
66
67 if (*lineptr == NULL || *n == 0)
68 {
69 *n = 120;
70 *lineptr = (char *) malloc (*n);
71 if (*lineptr == NULL)
72 {
73 result = -1;
74 goto unlock_return;
75 }
76 }
77
78 for (;;)
79 {
80 int i;
81
82 i = getc (fp);
83 if (i == EOF)
84 {
85 result = -1;
86 break;
87 }
88
89 /* Make enough space for len+1 (for final NUL) bytes. */
90 if (cur_len + 1 >= *n)
91 {
92 size_t needed_max =
93 SSIZE_MAX < SIZE_MAX ? (size_t) SSIZE_MAX + 1 : SIZE_MAX;
94 size_t needed = 2 * *n + 1; /* Be generous. */
95 char *new_lineptr;
96
97 if (needed_max < needed)
98 needed = needed_max;
99 if (cur_len + 1 >= needed)
100 {
101 result = -1;
102 goto unlock_return;
103 }
104
105 new_lineptr = (char *) realloc (*lineptr, needed);
106 if (new_lineptr == NULL)
107 {
108 result = -1;
109 goto unlock_return;
110 }
111
112 *lineptr = new_lineptr;
113 *n = needed;
114 }
115
116 (*lineptr)[cur_len] = i;
117 cur_len++;
118
119 if (i == delimiter)
120 break;
121 }
122 (*lineptr)[cur_len] = '\0';
123 result = cur_len ? cur_len : result;
124
125 unlock_return:
126 funlockfile (fp);
127 return result;
128 }
129