1/* Copyright (C) 1993-2023 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 "libioP.h"
28#include <string.h>
29
30size_t
31_IO_getline (FILE *fp, char *buf, size_t n, int delim,
32 int extract_delim)
33{
34 return _IO_getline_info (fp, buf, n, delim, extract_delim, (int *) 0);
35}
36libc_hidden_def (_IO_getline)
37
38/* Algorithm based on that used by Berkeley pre-4.4 fgets implementation.
39
40 Read chars into buf (of size n), until delim is seen.
41 Return number of chars read (at most n).
42 Does not put a terminating '\0' in buf.
43 If extract_delim < 0, leave delimiter unread.
44 If extract_delim > 0, insert delim in output. */
45
46size_t
47_IO_getline_info (FILE *fp, char *buf, size_t n, int delim,
48 int extract_delim, int *eof)
49{
50 char *ptr = buf;
51 if (eof != NULL)
52 *eof = 0;
53 if (__builtin_expect (fp->_mode, -1) == 0)
54 _IO_fwide (fp, -1);
55 while (n != 0)
56 {
57 ssize_t len = fp->_IO_read_end - fp->_IO_read_ptr;
58 if (len <= 0)
59 {
60 int c = __uflow (fp);
61 if (c == EOF)
62 {
63 if (eof)
64 *eof = c;
65 break;
66 }
67 if (c == delim)
68 {
69 if (extract_delim > 0)
70 *ptr++ = c;
71 else if (extract_delim < 0)
72 _IO_sputbackc (fp, c);
73 if (extract_delim > 0)
74 ++len;
75 return ptr - buf;
76 }
77 *ptr++ = c;
78 n--;
79 }
80 else
81 {
82 char *t;
83 if ((size_t) len >= n)
84 len = n;
85 t = (char *) memchr ((void *) fp->_IO_read_ptr, delim, len);
86 if (t != NULL)
87 {
88 size_t old_len = ptr-buf;
89 len = t - fp->_IO_read_ptr;
90 if (extract_delim >= 0)
91 {
92 ++t;
93 if (extract_delim > 0)
94 ++len;
95 }
96 memcpy ((void *) ptr, (void *) fp->_IO_read_ptr, len);
97 fp->_IO_read_ptr = t;
98 return old_len + len;
99 }
100 memcpy ((void *) ptr, (void *) fp->_IO_read_ptr, len);
101 fp->_IO_read_ptr += len;
102 ptr += len;
103 n -= len;
104 }
105 }
106 return ptr - buf;
107}
108libc_hidden_def (_IO_getline_info)
109