1 | /* Copyright (C) 1993-2017 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 <fcntl.h> |
29 | #include <stdlib.h> |
30 | #include <stddef.h> |
31 | #ifdef _LIBC |
32 | # include <shlib-compat.h> |
33 | #else |
34 | # define _IO_new_fopen fopen |
35 | #endif |
36 | |
37 | _IO_FILE * |
38 | __fopen_maybe_mmap (_IO_FILE *fp) |
39 | { |
40 | #ifdef _G_HAVE_MMAP |
41 | if ((fp->_flags2 & _IO_FLAGS2_MMAP) && (fp->_flags & _IO_NO_WRITES)) |
42 | { |
43 | /* Since this is read-only, we might be able to mmap the contents |
44 | directly. We delay the decision until the first read attempt by |
45 | giving it a jump table containing functions that choose mmap or |
46 | vanilla file operations and reset the jump table accordingly. */ |
47 | |
48 | if (fp->_mode <= 0) |
49 | _IO_JUMPS_FILE_plus (fp) = &_IO_file_jumps_maybe_mmap; |
50 | else |
51 | _IO_JUMPS_FILE_plus (fp) = &_IO_wfile_jumps_maybe_mmap; |
52 | fp->_wide_data->_wide_vtable = &_IO_wfile_jumps_maybe_mmap; |
53 | } |
54 | #endif |
55 | return fp; |
56 | } |
57 | |
58 | |
59 | _IO_FILE * |
60 | __fopen_internal (const char *filename, const char *mode, int is32) |
61 | { |
62 | struct locked_FILE |
63 | { |
64 | struct _IO_FILE_plus fp; |
65 | #ifdef _IO_MTSAFE_IO |
66 | _IO_lock_t lock; |
67 | #endif |
68 | struct _IO_wide_data wd; |
69 | } *new_f = (struct locked_FILE *) malloc (sizeof (struct locked_FILE)); |
70 | |
71 | if (new_f == NULL) |
72 | return NULL; |
73 | #ifdef _IO_MTSAFE_IO |
74 | new_f->fp.file._lock = &new_f->lock; |
75 | #endif |
76 | #if defined _LIBC || defined _GLIBCPP_USE_WCHAR_T |
77 | _IO_no_init (&new_f->fp.file, 0, 0, &new_f->wd, &_IO_wfile_jumps); |
78 | #else |
79 | _IO_no_init (&new_f->fp.file, 1, 0, NULL, NULL); |
80 | #endif |
81 | _IO_JUMPS (&new_f->fp) = &_IO_file_jumps; |
82 | _IO_new_file_init_internal (&new_f->fp); |
83 | #if !_IO_UNIFIED_JUMPTABLES |
84 | new_f->fp.vtable = NULL; |
85 | #endif |
86 | if (_IO_file_fopen ((_IO_FILE *) new_f, filename, mode, is32) != NULL) |
87 | return __fopen_maybe_mmap (&new_f->fp.file); |
88 | |
89 | _IO_un_link (&new_f->fp); |
90 | free (new_f); |
91 | return NULL; |
92 | } |
93 | |
94 | _IO_FILE * |
95 | _IO_new_fopen (const char *filename, const char *mode) |
96 | { |
97 | return __fopen_internal (filename, mode, 1); |
98 | } |
99 | |
100 | #ifdef _LIBC |
101 | strong_alias (_IO_new_fopen, __new_fopen) |
102 | versioned_symbol (libc, _IO_new_fopen, _IO_fopen, GLIBC_2_1); |
103 | versioned_symbol (libc, __new_fopen, fopen, GLIBC_2_1); |
104 | |
105 | # if !defined O_LARGEFILE || O_LARGEFILE == 0 |
106 | weak_alias (_IO_new_fopen, _IO_fopen64) |
107 | weak_alias (_IO_new_fopen, fopen64) |
108 | # endif |
109 | #endif |
110 | |