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-rw-r--r--gl/ftello.c157
1 files changed, 0 insertions, 157 deletions
diff --git a/gl/ftello.c b/gl/ftello.c
deleted file mode 100644
index 989614a0..00000000
--- a/gl/ftello.c
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@@ -1,157 +0,0 @@
1/* An ftello() function that works around platform bugs.
2 Copyright (C) 2007, 2009-2022 Free Software Foundation, Inc.
3
4 This file is free software: you can redistribute it and/or modify
5 it under the terms of the GNU Lesser General Public License as
6 published by the Free Software Foundation; either version 2.1 of the
7 License, or (at your option) any later version.
8
9 This file 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
12 GNU Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17#include <config.h>
18
19/* Specification. */
20#include <stdio.h>
21
22#include <errno.h>
23#include "intprops.h"
24
25/* Get lseek. */
26#include <unistd.h>
27
28#include "stdio-impl.h"
29
30off_t
31ftello (FILE *fp)
32#undef ftello
33#if !HAVE_FTELLO
34# undef ftell
35# define ftello ftell
36#endif
37#if _GL_WINDOWS_64_BIT_OFF_T
38# undef ftello
39# if HAVE__FTELLI64 /* msvc, mingw64 */
40# define ftello _ftelli64
41# else /* mingw */
42# define ftello ftello64
43# endif
44#endif
45{
46#if FTELLO_BROKEN_AFTER_UNGETC /* macOS >= 10.15 */
47 /* The system's ftello() is completely broken, because it calls __sflush,
48 which makes side effects on the stream. */
49
50 /* Handle non-seekable files first. */
51 if (fp->_file < 0 || fp->_seek == NULL)
52 {
53 errno = ESPIPE;
54 return -1;
55 }
56
57 /* Determine the current offset, ignoring buffered and pushed-back bytes. */
58 off_t pos;
59
60 if (fp->_flags & __SOFF)
61 pos = fp->_offset;
62 else
63 {
64 pos = fp->_seek (fp->_cookie, 0, SEEK_CUR);
65 if (pos < 0)
66 return -1;
67 if (fp->_flags & __SOPT)
68 {
69 fp->_offset = pos;
70 fp->_flags |= __SOFF;
71 }
72 }
73
74 if (fp->_flags & __SRD)
75 {
76 /* Now consider buffered and pushed-back bytes from ungetc. */
77 if (fp->_ub._base != NULL)
78 /* Considering the buffered bytes, we are at position
79 pos - fp->_ur.
80 Considering also the pushed-back bytes, we are at position
81 pos - fp->_ur - fp->_r. */
82 pos = pos - fp->_ur - fp->_r;
83 else
84 /* Considering the buffered bytes, we are at position
85 pos - fp->_r. */
86 pos = pos - fp->_r;
87 if (pos < 0)
88 {
89 errno = EIO;
90 return -1;
91 }
92 }
93 else if ((fp->_flags & __SWR) && fp->_p != NULL)
94 {
95 /* Consider the buffered bytes. */
96 off_t buffered = fp->_p - fp->_bf._base;
97
98 /* Compute pos + buffered, with overflow check. */
99 off_t sum;
100 if (! INT_ADD_OK (pos, buffered, &sum))
101 {
102 errno = EOVERFLOW;
103 return -1;
104 }
105 pos = sum;
106 }
107
108 return pos;
109
110#else
111
112# if LSEEK_PIPE_BROKEN
113 /* mingw gives bogus answers rather than failure on non-seekable files. */
114 if (lseek (fileno (fp), 0, SEEK_CUR) == -1)
115 return -1;
116# endif
117
118# if FTELLO_BROKEN_AFTER_SWITCHING_FROM_READ_TO_WRITE /* Solaris */
119 /* The Solaris stdio leaves the _IOREAD flag set after reading from a file
120 reaches EOF and the program then starts writing to the file. ftello
121 gets confused by this. */
122 if (fp_->_flag & _IOWRT)
123 {
124 off_t pos;
125
126 /* Call ftello nevertheless, for the side effects that it does on fp. */
127 ftello (fp);
128
129 /* Compute the file position ourselves. */
130 pos = lseek (fileno (fp), (off_t) 0, SEEK_CUR);
131 if (pos >= 0)
132 {
133 if ((fp_->_flag & _IONBF) == 0 && fp_->_base != NULL)
134 pos += fp_->_ptr - fp_->_base;
135 }
136 return pos;
137 }
138# endif
139
140# if defined __SL64 && defined __SCLE /* Cygwin */
141 if ((fp->_flags & __SL64) == 0)
142 {
143 /* Cygwin 1.5.0 through 1.5.24 failed to open stdin in 64-bit
144 mode; but has an ftello that requires 64-bit mode. */
145 FILE *tmp = fopen ("/dev/null", "r");
146 if (!tmp)
147 return -1;
148 fp->_flags |= __SL64;
149 fp->_seek64 = tmp->_seek64;
150 fclose (tmp);
151 }
152# endif
153
154 return ftello (fp);
155
156#endif
157}