1 | /* Copyright (C) 1993-2019 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 <shlib-compat.h> |
28 | #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1) |
29 | |
30 | #define _IO_USE_OLD_IO_FILE |
31 | #include <stdlib.h> |
32 | #include "libioP.h" |
33 | #include <fcntl.h> |
34 | |
35 | FILE * |
36 | attribute_compat_text_section |
37 | _IO_old_fdopen (int fd, const char *mode) |
38 | { |
39 | int read_write; |
40 | int posix_mode = 0; |
41 | struct locked_FILE |
42 | { |
43 | struct _IO_FILE_complete_plus fp; |
44 | #ifdef _IO_MTSAFE_IO |
45 | _IO_lock_t lock; |
46 | #endif |
47 | } *new_f; |
48 | int fd_flags; |
49 | |
50 | switch (*mode++) |
51 | { |
52 | case 'r': |
53 | read_write = _IO_NO_WRITES; |
54 | break; |
55 | case 'w': |
56 | read_write = _IO_NO_READS; |
57 | break; |
58 | case 'a': |
59 | posix_mode = O_APPEND; |
60 | read_write = _IO_NO_READS|_IO_IS_APPENDING; |
61 | break; |
62 | default: |
63 | __set_errno (EINVAL); |
64 | return NULL; |
65 | } |
66 | if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+')) |
67 | read_write &= _IO_IS_APPENDING; |
68 | fd_flags = __fcntl (fd, F_GETFL); |
69 | if (fd_flags == -1 |
70 | || ((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES)) |
71 | || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS))) |
72 | return NULL; |
73 | |
74 | /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b) |
75 | [System Application Program Interface (API) Amendment 1: |
76 | Realtime Extensions], Rationale B.8.3.3 |
77 | Open a Stream on a File Descriptor says: |
78 | |
79 | Although not explicitly required by POSIX.1, a good |
80 | implementation of append ("a") mode would cause the |
81 | O_APPEND flag to be set. |
82 | |
83 | (Historical implementations [such as Solaris2] do a one-time |
84 | seek in fdopen.) |
85 | |
86 | However, we do not turn O_APPEND off if the mode is "w" (even |
87 | though that would seem consistent) because that would be more |
88 | likely to break historical programs. |
89 | */ |
90 | if ((posix_mode & O_APPEND) && !(fd_flags & O_APPEND)) |
91 | { |
92 | if (__fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1) |
93 | return NULL; |
94 | } |
95 | |
96 | new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE)); |
97 | if (new_f == NULL) |
98 | return NULL; |
99 | #ifdef _IO_MTSAFE_IO |
100 | new_f->fp.file._file._lock = &new_f->lock; |
101 | #endif |
102 | _IO_old_init (&new_f->fp.file._file, 0); |
103 | _IO_JUMPS_FILE_plus (&new_f->fp) = &_IO_old_file_jumps; |
104 | _IO_old_file_init_internal ((struct _IO_FILE_plus *) &new_f->fp); |
105 | if (_IO_old_file_attach (&new_f->fp.file._file, fd) == NULL) |
106 | { |
107 | _IO_un_link ((struct _IO_FILE_plus *) &new_f->fp); |
108 | free (new_f); |
109 | return NULL; |
110 | } |
111 | new_f->fp.file._file._flags &= ~_IO_DELETE_DONT_CLOSE; |
112 | |
113 | _IO_mask_flags (&new_f->fp.file._file, read_write, |
114 | _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING); |
115 | |
116 | return (FILE *) &new_f->fp; |
117 | } |
118 | |
119 | strong_alias (_IO_old_fdopen, __old_fdopen) |
120 | compat_symbol (libc, _IO_old_fdopen, _IO_fdopen, GLIBC_2_0); |
121 | compat_symbol (libc, __old_fdopen, fdopen, GLIBC_2_0); |
122 | |
123 | #endif |
124 | |