1 | /*
|
---|
2 | * io.h --- the I/O manager abstraction
|
---|
3 | *
|
---|
4 | * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
|
---|
5 | *
|
---|
6 | * %Begin-Header%
|
---|
7 | * This file may be redistributed under the terms of the GNU Public
|
---|
8 | * License.
|
---|
9 | * %End-Header%
|
---|
10 | */
|
---|
11 |
|
---|
12 | #ifndef _EXT2FS_EXT2_IO_H
|
---|
13 | #define _EXT2FS_EXT2_IO_H
|
---|
14 |
|
---|
15 | /*
|
---|
16 | * ext2_loff_t is defined here since unix_io.c needs it.
|
---|
17 | */
|
---|
18 | #if defined(__GNUC__) || defined(HAS_LONG_LONG)
|
---|
19 | typedef long long ext2_loff_t;
|
---|
20 | #else
|
---|
21 | typedef long ext2_loff_t;
|
---|
22 | #endif
|
---|
23 |
|
---|
24 | /* llseek.c */
|
---|
25 | /* ext2_loff_t ext2fs_llseek (int, ext2_loff_t, int); */
|
---|
26 | #ifdef CONFIG_LFS
|
---|
27 | # define ext2fs_llseek lseek64
|
---|
28 | #else
|
---|
29 | # define ext2fs_llseek lseek
|
---|
30 | #endif
|
---|
31 |
|
---|
32 | typedef struct struct_io_manager *io_manager;
|
---|
33 | typedef struct struct_io_channel *io_channel;
|
---|
34 |
|
---|
35 | #define CHANNEL_FLAGS_WRITETHROUGH 0x01
|
---|
36 |
|
---|
37 | struct struct_io_channel {
|
---|
38 | errcode_t magic;
|
---|
39 | io_manager manager;
|
---|
40 | char *name;
|
---|
41 | int block_size;
|
---|
42 | errcode_t (*read_error)(io_channel channel,
|
---|
43 | unsigned long block,
|
---|
44 | int count,
|
---|
45 | void *data,
|
---|
46 | size_t size,
|
---|
47 | int actual_bytes_read,
|
---|
48 | errcode_t error);
|
---|
49 | errcode_t (*write_error)(io_channel channel,
|
---|
50 | unsigned long block,
|
---|
51 | int count,
|
---|
52 | const void *data,
|
---|
53 | size_t size,
|
---|
54 | int actual_bytes_written,
|
---|
55 | errcode_t error);
|
---|
56 | int refcount;
|
---|
57 | int flags;
|
---|
58 | int reserved[14];
|
---|
59 | void *private_data;
|
---|
60 | void *app_data;
|
---|
61 | };
|
---|
62 |
|
---|
63 | struct struct_io_manager {
|
---|
64 | errcode_t magic;
|
---|
65 | const char *name;
|
---|
66 | errcode_t (*open)(const char *name, int flags, io_channel *channel);
|
---|
67 | errcode_t (*close)(io_channel channel);
|
---|
68 | errcode_t (*set_blksize)(io_channel channel, int blksize);
|
---|
69 | errcode_t (*read_blk)(io_channel channel, unsigned long block,
|
---|
70 | int count, void *data);
|
---|
71 | errcode_t (*write_blk)(io_channel channel, unsigned long block,
|
---|
72 | int count, const void *data);
|
---|
73 | errcode_t (*flush)(io_channel channel);
|
---|
74 | errcode_t (*write_byte)(io_channel channel, unsigned long offset,
|
---|
75 | int count, const void *data);
|
---|
76 | errcode_t (*set_option)(io_channel channel, const char *option,
|
---|
77 | const char *arg);
|
---|
78 | int reserved[14];
|
---|
79 | };
|
---|
80 |
|
---|
81 | #define IO_FLAG_RW 1
|
---|
82 |
|
---|
83 | /*
|
---|
84 | * Convenience functions....
|
---|
85 | */
|
---|
86 | #define io_channel_close(c) ((c)->manager->close((c)))
|
---|
87 | #define io_channel_set_blksize(c,s) ((c)->manager->set_blksize((c),s))
|
---|
88 | #define io_channel_read_blk(c,b,n,d) ((c)->manager->read_blk((c),b,n,d))
|
---|
89 | #define io_channel_write_blk(c,b,n,d) ((c)->manager->write_blk((c),b,n,d))
|
---|
90 | #define io_channel_flush(c) ((c)->manager->flush((c)))
|
---|
91 | #define io_channel_bumpcount(c) ((c)->refcount++)
|
---|
92 |
|
---|
93 | /* io_manager.c */
|
---|
94 | extern errcode_t io_channel_set_options(io_channel channel,
|
---|
95 | const char *options);
|
---|
96 | extern errcode_t io_channel_write_byte(io_channel channel,
|
---|
97 | unsigned long offset,
|
---|
98 | int count, const void *data);
|
---|
99 |
|
---|
100 | /* unix_io.c */
|
---|
101 | extern io_manager unix_io_manager;
|
---|
102 |
|
---|
103 | /* test_io.c */
|
---|
104 | extern io_manager test_io_manager, test_io_backing_manager;
|
---|
105 | extern void (*test_io_cb_read_blk)
|
---|
106 | (unsigned long block, int count, errcode_t err);
|
---|
107 | extern void (*test_io_cb_write_blk)
|
---|
108 | (unsigned long block, int count, errcode_t err);
|
---|
109 | extern void (*test_io_cb_set_blksize)
|
---|
110 | (int blksize, errcode_t err);
|
---|
111 |
|
---|
112 | #endif /* _EXT2FS_EXT2_IO_H */
|
---|
113 |
|
---|