diff options
Diffstat (limited to 'lib/ext2fs/ext2_io.h')
| -rw-r--r-- | lib/ext2fs/ext2_io.h | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/lib/ext2fs/ext2_io.h b/lib/ext2fs/ext2_io.h new file mode 100644 index 0000000..679184e --- /dev/null +++ b/lib/ext2fs/ext2_io.h @@ -0,0 +1,179 @@ +/* + * io.h --- the I/O manager abstraction + * + * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o. + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Library + * General Public License, version 2. + * %End-Header% + */ + +#ifndef _EXT2FS_EXT2_IO_H +#define _EXT2FS_EXT2_IO_H + +#include <ext2fs/ext2_types.h> + +/* + * ext2_loff_t is defined here since unix_io.c needs it. + */ +#if defined(__GNUC__) || defined(HAS_LONG_LONG) +typedef long long ext2_loff_t; +#else +typedef long ext2_loff_t; +#endif + +/* llseek.c */ +ext2_loff_t ext2fs_llseek (int, ext2_loff_t, int); + +typedef struct struct_io_manager *io_manager; +typedef struct struct_io_channel *io_channel; +typedef struct struct_io_stats *io_stats; + +#define CHANNEL_FLAGS_WRITETHROUGH 0x01 +#define CHANNEL_FLAGS_DISCARD_ZEROES 0x02 +#define CHANNEL_FLAGS_BLOCK_DEVICE 0x04 +#define CHANNEL_FLAGS_THREADS 0x08 + +#define io_channel_discard_zeroes_data(i) (i->flags & CHANNEL_FLAGS_DISCARD_ZEROES) + +struct struct_io_channel { + errcode_t magic; + io_manager manager; + char *name; + int block_size; + errcode_t (*read_error)(io_channel channel, + unsigned long block, + int count, + void *data, + size_t size, + int actual_bytes_read, + errcode_t error); + errcode_t (*write_error)(io_channel channel, + unsigned long block, + int count, + const void *data, + size_t size, + int actual_bytes_written, + errcode_t error); + int refcount; + int flags; + long reserved[14]; + void *private_data; + void *app_data; + int align; +}; + +struct struct_io_stats { + int num_fields; + int reserved; + unsigned long long bytes_read; + unsigned long long bytes_written; +}; + +struct struct_io_manager { + errcode_t magic; + const char *name; + errcode_t (*open)(const char *name, int flags, io_channel *channel); + errcode_t (*close)(io_channel channel); + errcode_t (*set_blksize)(io_channel channel, int blksize); + errcode_t (*read_blk)(io_channel channel, unsigned long block, + int count, void *data); + errcode_t (*write_blk)(io_channel channel, unsigned long block, + int count, const void *data); + errcode_t (*flush)(io_channel channel); + errcode_t (*write_byte)(io_channel channel, unsigned long offset, + int count, const void *data); + errcode_t (*set_option)(io_channel channel, const char *option, + const char *arg); + errcode_t (*get_stats)(io_channel channel, io_stats *io_stats); + errcode_t (*read_blk64)(io_channel channel, unsigned long long block, + int count, void *data); + errcode_t (*write_blk64)(io_channel channel, unsigned long long block, + int count, const void *data); + errcode_t (*discard)(io_channel channel, unsigned long long block, + unsigned long long count); + errcode_t (*cache_readahead)(io_channel channel, + unsigned long long block, + unsigned long long count); + errcode_t (*zeroout)(io_channel channel, unsigned long long block, + unsigned long long count); + long reserved[14]; +}; + +#define IO_FLAG_RW 0x0001 +#define IO_FLAG_EXCLUSIVE 0x0002 +#define IO_FLAG_DIRECT_IO 0x0004 +#define IO_FLAG_FORCE_BOUNCE 0x0008 +#define IO_FLAG_THREADS 0x0010 +#define IO_FLAG_NOCACHE 0x0020 + +/* + * Convenience functions.... + */ +#define io_channel_close(c) ((c)->manager->close((c))) +#define io_channel_set_blksize(c,s) ((c)->manager->set_blksize((c),s)) +#define io_channel_read_blk(c,b,n,d) ((c)->manager->read_blk((c),b,n,d)) +#define io_channel_write_blk(c,b,n,d) ((c)->manager->write_blk((c),b,n,d)) +#define io_channel_flush(c) ((c)->manager->flush((c))) +#define io_channel_bumpcount(c) ((c)->refcount++) + +/* io_manager.c */ +extern errcode_t io_channel_set_options(io_channel channel, + const char *options); +extern errcode_t io_channel_write_byte(io_channel channel, + unsigned long offset, + int count, const void *data); +extern errcode_t io_channel_read_blk64(io_channel channel, + unsigned long long block, + int count, void *data); +extern errcode_t io_channel_write_blk64(io_channel channel, + unsigned long long block, + int count, const void *data); +extern errcode_t io_channel_discard(io_channel channel, + unsigned long long block, + unsigned long long count); +extern errcode_t io_channel_zeroout(io_channel channel, + unsigned long long block, + unsigned long long count); +extern errcode_t io_channel_alloc_buf(io_channel channel, + int count, void *ptr); +extern errcode_t io_channel_cache_readahead(io_channel io, + unsigned long long block, + unsigned long long count); + +#ifdef _WIN32 +/* windows_io.c */ +extern io_manager windows_io_manager; +#define default_io_manager windows_io_manager +#else +/* unix_io.c */ +extern io_manager unix_io_manager; +extern io_manager unixfd_io_manager; +#define default_io_manager unix_io_manager +#endif + +/* sparse_io.c */ +extern io_manager sparse_io_manager; +extern io_manager sparsefd_io_manager; + +/* undo_io.c */ +extern io_manager undo_io_manager; +extern errcode_t set_undo_io_backing_manager(io_manager manager); +extern errcode_t set_undo_io_backup_file(char *file_name); + +/* test_io.c */ +extern io_manager test_io_manager, test_io_backing_manager; +extern void (*test_io_cb_read_blk) + (unsigned long block, int count, errcode_t err); +extern void (*test_io_cb_write_blk) + (unsigned long block, int count, errcode_t err); +extern void (*test_io_cb_read_blk64) + (unsigned long long block, int count, errcode_t err); +extern void (*test_io_cb_write_blk64) + (unsigned long long block, int count, errcode_t err); +extern void (*test_io_cb_set_blksize) + (int blksize, errcode_t err); + +#endif /* _EXT2FS_EXT2_IO_H */ + |