Update.
[glibc.git] / libio / iofdopen.c
blob0a867f7c574f5c397031c9456d55ef97661c5af6
1 /* Copyright (C) 1993, 1994, 1997-1999, 2000 Free Software Foundation, Inc.
2 This file is part of the GNU IO Library.
4 This library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU General Public License as
6 published by the Free Software Foundation; either version 2, or (at
7 your option) any later version.
9 This library is distributed in the hope that it will be useful, but
10 WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this library; see the file COPYING. If not, write to
16 the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
17 MA 02111-1307, USA.
19 As a special exception, if you link this library with files
20 compiled with a GNU compiler to produce an executable, this does
21 not cause the resulting executable to be covered by the GNU General
22 Public License. This exception does not however invalidate any
23 other reasons why the executable file might be covered by the GNU
24 General Public License. */
26 #ifdef __STDC__
27 # include <stdlib.h>
28 #endif
29 #include "libioP.h"
30 #include <fcntl.h>
32 #ifdef _LIBC
33 # include <shlib-compat.h>
34 #endif
36 #ifndef _IO_fcntl
37 #ifdef _LIBC
38 #define _IO_fcntl __fcntl
39 #else
40 #define _IO_fcntl fcntl
41 #endif
42 #endif
44 _IO_FILE *
45 _IO_new_fdopen (fd, mode)
46 int fd;
47 const char *mode;
49 int read_write;
50 int posix_mode = 0;
51 struct locked_FILE
53 struct _IO_FILE_plus fp;
54 #ifdef _IO_MTSAFE_IO
55 _IO_lock_t lock;
56 #endif
57 struct _IO_wide_data wd;
58 } *new_f;
59 int fd_flags;
61 switch (*mode++)
63 case 'r':
64 read_write = _IO_NO_WRITES;
65 break;
66 case 'w':
67 read_write = _IO_NO_READS;
68 break;
69 case 'a':
70 posix_mode = O_APPEND;
71 read_write = _IO_NO_READS|_IO_IS_APPENDING;
72 break;
73 default:
74 MAYBE_SET_EINVAL;
75 return NULL;
77 if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
78 read_write &= _IO_IS_APPENDING;
79 #ifdef F_GETFL
80 fd_flags = _IO_fcntl (fd, F_GETFL);
81 #ifndef O_ACCMODE
82 #define O_ACCMODE (O_RDONLY|O_WRONLY|O_RDWR)
83 #endif
84 if (fd_flags == -1)
85 return NULL;
87 if (((fd_flags & O_ACCMODE) == O_RDONLY && !(read_write & _IO_NO_WRITES))
88 || ((fd_flags & O_ACCMODE) == O_WRONLY && !(read_write & _IO_NO_READS)))
90 MAYBE_SET_EINVAL;
91 return NULL;
94 /* The May 93 draft of P1003.4/D14.1 (redesignated as 1003.1b)
95 [System Application Program Interface (API) Amendment 1:
96 Realtime Extensions], Rationale B.8.3.3
97 Open a Stream on a File Descriptor says:
99 Although not explicitly required by POSIX.1, a good
100 implementation of append ("a") mode would cause the
101 O_APPEND flag to be set.
103 (Historical implementations [such as Solaris2] do a one-time
104 seek in fdopen.)
106 However, we do not turn O_APPEND off if the mode is "w" (even
107 though that would seem consistent) because that would be more
108 likely to break historical programs.
110 if ((posix_mode & O_APPEND) && !(fd_flags & O_APPEND))
112 #ifdef F_SETFL
113 if (_IO_fcntl (fd, F_SETFL, fd_flags | O_APPEND) == -1)
114 #endif
115 return NULL;
117 #endif
119 new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE));
120 if (new_f == NULL)
121 return NULL;
122 #ifdef _IO_MTSAFE_IO
123 new_f->fp.file._lock = &new_f->lock;
124 #endif
125 _IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd, &_IO_wfile_jumps);
126 _IO_JUMPS (&new_f->fp) = &_IO_file_jumps;
127 _IO_file_init (&new_f->fp);
128 #if !_IO_UNIFIED_JUMPTABLES
129 new_f->fp.vtable = NULL;
130 #endif
131 if (_IO_file_attach ((_IO_FILE *) &new_f->fp, fd) == NULL)
133 _IO_un_link (&new_f->fp);
134 free (new_f);
135 return NULL;
137 new_f->fp.file._flags &= ~_IO_DELETE_DONT_CLOSE;
139 new_f->fp.file._IO_file_flags =
140 _IO_mask_flags (&new_f->fp.file, read_write,
141 _IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
143 return (_IO_FILE *) &new_f->fp;
146 strong_alias (_IO_new_fdopen, __new_fdopen)
147 versioned_symbol (libc, _IO_new_fdopen, _IO_fdopen, GLIBC_2_1);
148 versioned_symbol (libc, __new_fdopen, fdopen, GLIBC_2_1);