1 /* vi: set sw=4 ts=4: */
3 * io.h --- the I/O manager abstraction
5 * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
8 * This file may be redistributed under the terms of the GNU Public
12 #ifndef EXT2FS_EXT2_IO_H
13 #define EXT2FS_EXT2_IO_H 1
16 * ext2_loff_t is defined here since unix_io.c needs it.
18 #if defined(__GNUC__) || defined(HAS_LONG_LONG)
19 typedef long long ext2_loff_t
;
21 typedef long ext2_loff_t
;
25 /* ext2_loff_t ext2fs_llseek (int, ext2_loff_t, int); */
27 # define ext2fs_llseek lseek64
29 # define ext2fs_llseek lseek
32 typedef struct struct_io_manager
*io_manager
;
33 typedef struct struct_io_channel
*io_channel
;
35 #define CHANNEL_FLAGS_WRITETHROUGH 0x01
37 struct struct_io_channel
{
42 errcode_t (*read_error
)(io_channel channel
,
47 int actual_bytes_read
,
49 errcode_t (*write_error
)(io_channel channel
,
54 int actual_bytes_written
,
63 struct struct_io_manager
{
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
,
84 * Convenience functions....
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++)
94 extern errcode_t
io_channel_set_options(io_channel channel
,
96 extern errcode_t
io_channel_write_byte(io_channel channel
,
98 int count
, const void *data
);
101 extern io_manager unix_io_manager
;
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
);