1 | /* Copyright (C) 1993-2018 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 | <http://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 "stdio.h" |
29 | #include <fcntl.h> |
30 | #include <stdlib.h> |
31 | #include <unistd.h> |
32 | |
33 | #include <fd_to_filename.h> |
34 | |
35 | #include <kernel-features.h> |
36 | |
37 | FILE * |
38 | freopen64 (const char *filename, const char *mode, FILE *fp) |
39 | { |
40 | FILE *result; |
41 | CHECK_FILE (fp, NULL); |
42 | if (!(fp->_flags & _IO_IS_FILEBUF)) |
43 | return NULL; |
44 | _IO_acquire_lock (fp); |
45 | int fd = _IO_fileno (fp); |
46 | const char *gfilename = (filename == NULL && fd >= 0 |
47 | ? fd_to_filename (fd) : filename); |
48 | fp->_flags2 |= _IO_FLAGS2_NOCLOSE; |
49 | _IO_file_close_it (fp); |
50 | _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps; |
51 | if (_IO_vtable_offset (fp) == 0 && fp->_wide_data != NULL) |
52 | fp->_wide_data->_wide_vtable = &_IO_wfile_jumps; |
53 | result = _IO_file_fopen (fp, gfilename, mode, 0); |
54 | fp->_flags2 &= ~_IO_FLAGS2_NOCLOSE; |
55 | if (result != NULL) |
56 | result = __fopen_maybe_mmap (result); |
57 | if (result != NULL) |
58 | { |
59 | /* unbound stream orientation */ |
60 | result->_mode = 0; |
61 | |
62 | if (fd != -1 && _IO_fileno (result) != fd) |
63 | { |
64 | /* At this point we have both file descriptors already allocated, |
65 | so __dup3 will not fail with EBADF, EINVAL, or EMFILE. But |
66 | we still need to check for EINVAL and, due Linux internal |
67 | implementation, EBUSY. It is because on how it internally opens |
68 | the file by splitting the buffer allocation operation and VFS |
69 | opening (a dup operation may run when a file is still pending |
70 | 'install' on VFS). */ |
71 | if (__dup3 (_IO_fileno (result), fd, |
72 | (result->_flags2 & _IO_FLAGS2_CLOEXEC) != 0 |
73 | ? O_CLOEXEC : 0) == -1) |
74 | { |
75 | _IO_file_close_it (result); |
76 | result = NULL; |
77 | goto end; |
78 | } |
79 | __close (_IO_fileno (result)); |
80 | _IO_fileno (result) = fd; |
81 | } |
82 | } |
83 | else if (fd != -1) |
84 | __close (fd); |
85 | |
86 | end: |
87 | if (filename == NULL) |
88 | free ((char *) gfilename); |
89 | _IO_release_lock (fp); |
90 | return result; |
91 | } |
92 | |