1/* Copyright (C) 1994-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>.
17
18 As a special exception, if you link the code in this file with
19 files compiled with a GNU compiler to produce an executable,
20 that does not cause the resulting executable to be covered by
21 the GNU Lesser General Public License. This exception does not
22 however invalidate any other reasons why the executable file
23 might be covered by the GNU Lesser General Public License.
24 This exception applies to code released by its copyright holders
25 in files containing the exception. */
26
27#include <stdlib.h>
28#include "libioP.h"
29#include <string.h>
30#include <errno.h>
31#include <limits.h>
32
33/* Read up to (and including) a TERMINATOR from FP into *LINEPTR
34 (and null-terminate it). *LINEPTR is a pointer returned from malloc (or
35 NULL), pointing to *N characters of space. It is realloc'ed as
36 necessary. Returns the number of characters read (not including the
37 null terminator), or -1 on error or EOF. */
38
39ssize_t
40_IO_getdelim (char **lineptr, size_t *n, int delimiter, FILE *fp)
41{
42 ssize_t result;
43 ssize_t cur_len = 0;
44 ssize_t len;
45
46 if (lineptr == NULL || n == NULL)
47 {
48 __set_errno (EINVAL);
49 return -1;
50 }
51 CHECK_FILE (fp, -1);
52 _IO_acquire_lock (fp);
53 if (_IO_ferror_unlocked (fp))
54 {
55 result = -1;
56 goto unlock_return;
57 }
58
59 if (*lineptr == NULL || *n == 0)
60 {
61 *n = 120;
62 *lineptr = (char *) malloc (*n);
63 if (*lineptr == NULL)
64 {
65 result = -1;
66 goto unlock_return;
67 }
68 }
69
70 len = fp->_IO_read_end - fp->_IO_read_ptr;
71 if (len <= 0)
72 {
73 if (__underflow (fp) == EOF)
74 {
75 result = -1;
76 goto unlock_return;
77 }
78 len = fp->_IO_read_end - fp->_IO_read_ptr;
79 }
80
81 for (;;)
82 {
83 size_t needed;
84 char *t;
85 t = (char *) memchr ((void *) fp->_IO_read_ptr, delimiter, len);
86 if (t != NULL)
87 len = (t - fp->_IO_read_ptr) + 1;
88 if (__glibc_unlikely (len >= SSIZE_MAX - cur_len))
89 {
90 __set_errno (EOVERFLOW);
91 result = -1;
92 goto unlock_return;
93 }
94 /* Make enough space for len+1 (for final NUL) bytes. */
95 needed = cur_len + len + 1;
96 if (needed > *n)
97 {
98 char *new_lineptr;
99
100 if (needed < 2 * *n)
101 needed = 2 * *n; /* Be generous. */
102 new_lineptr = (char *) realloc (*lineptr, needed);
103 if (new_lineptr == NULL)
104 {
105 result = -1;
106 goto unlock_return;
107 }
108 *lineptr = new_lineptr;
109 *n = needed;
110 }
111 memcpy (*lineptr + cur_len, (void *) fp->_IO_read_ptr, len);
112 fp->_IO_read_ptr += len;
113 cur_len += len;
114 if (t != NULL || __underflow (fp) == EOF)
115 break;
116 len = fp->_IO_read_end - fp->_IO_read_ptr;
117 }
118 (*lineptr)[cur_len] = '\0';
119 result = cur_len;
120
121unlock_return:
122 _IO_release_lock (fp);
123 return result;
124}
125
126weak_alias (_IO_getdelim, __getdelim)
127weak_alias (_IO_getdelim, getdelim)
128