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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:49:25 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 15:49:25 +0000 |
commit | 464df1d5e5ab1322e2dd0a7796939fff1aeefa9a (patch) | |
tree | 6a403684e0978f0287d7f0ec0e5aab1fd31a59e1 /lib/ext2fs/inode_io.c | |
parent | Initial commit. (diff) | |
download | e2fsprogs-upstream/1.47.0.tar.xz e2fsprogs-upstream/1.47.0.zip |
Adding upstream version 1.47.0.upstream/1.47.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/ext2fs/inode_io.c | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/lib/ext2fs/inode_io.c b/lib/ext2fs/inode_io.c new file mode 100644 index 0000000..d7474a6 --- /dev/null +++ b/lib/ext2fs/inode_io.c @@ -0,0 +1,290 @@ +/* + * inode_io.c --- This is allows an inode in an ext2 filesystem image + * to be accessed via the I/O manager interface. + * + * Copyright (C) 2002 Theodore Ts'o. + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Library + * General Public License, version 2. + * %End-Header% + */ + +#include "config.h" +#include <stdio.h> +#include <string.h> +#if HAVE_UNISTD_H +#include <unistd.h> +#endif +#if HAVE_ERRNO_H +#include <errno.h> +#endif +#include <time.h> + +#include "ext2_fs.h" +#include "ext2fs.h" + +/* + * For checking structure magic numbers... + */ + +#define EXT2_CHECK_MAGIC(struct, code) \ + if ((struct)->magic != (code)) return (code) + +struct inode_private_data { + int magic; + char name[32]; + ext2_file_t file; + ext2_filsys fs; + ext2_ino_t ino; + struct ext2_inode inode; + int flags; + struct inode_private_data *next; +}; + +#define CHANNEL_HAS_INODE 0x8000 + +static struct inode_private_data *top_intern; +static int ino_unique = 0; + +static errcode_t inode_open(const char *name, int flags, io_channel *channel); +static errcode_t inode_close(io_channel channel); +static errcode_t inode_set_blksize(io_channel channel, int blksize); +static errcode_t inode_read_blk(io_channel channel, unsigned long block, + int count, void *data); +static errcode_t inode_write_blk(io_channel channel, unsigned long block, + int count, const void *data); +static errcode_t inode_flush(io_channel channel); +static errcode_t inode_write_byte(io_channel channel, unsigned long offset, + int size, const void *data); +static errcode_t inode_read_blk64(io_channel channel, + unsigned long long block, int count, void *data); +static errcode_t inode_write_blk64(io_channel channel, + unsigned long long block, int count, const void *data); + +static struct struct_io_manager struct_inode_manager = { + .magic = EXT2_ET_MAGIC_IO_MANAGER, + .name = "Inode I/O Manager", + .open = inode_open, + .close = inode_close, + .set_blksize = inode_set_blksize, + .read_blk = inode_read_blk, + .write_blk = inode_write_blk, + .flush = inode_flush, + .write_byte = inode_write_byte, + .read_blk64 = inode_read_blk64, + .write_blk64 = inode_write_blk64 +}; + +io_manager inode_io_manager = &struct_inode_manager; + +errcode_t ext2fs_inode_io_intern2(ext2_filsys fs, ext2_ino_t ino, + struct ext2_inode *inode, + char **name) +{ + struct inode_private_data *data; + errcode_t retval; + + if ((retval = ext2fs_get_mem(sizeof(struct inode_private_data), + &data))) + return retval; + data->magic = EXT2_ET_MAGIC_INODE_IO_CHANNEL; + sprintf(data->name, "%u:%d", ino, ino_unique++); + data->file = 0; + data->fs = fs; + data->ino = ino; + data->flags = 0; + if (inode) { + memcpy(&data->inode, inode, sizeof(struct ext2_inode)); + data->flags |= CHANNEL_HAS_INODE; + } + data->next = top_intern; + top_intern = data; + *name = data->name; + return 0; +} + +errcode_t ext2fs_inode_io_intern(ext2_filsys fs, ext2_ino_t ino, + char **name) +{ + return ext2fs_inode_io_intern2(fs, ino, NULL, name); +} + + +static errcode_t inode_open(const char *name, int flags, io_channel *channel) +{ + io_channel io = NULL; + struct inode_private_data *prev, *data = NULL; + errcode_t retval; + int open_flags; + + if (name == 0) + return EXT2_ET_BAD_DEVICE_NAME; + + for (data = top_intern, prev = NULL; data; + prev = data, data = data->next) + if (strcmp(name, data->name) == 0) + break; + if (!data) + return ENOENT; + if (prev) + prev->next = data->next; + else + top_intern = data->next; + + retval = ext2fs_get_mem(sizeof(struct struct_io_channel), &io); + if (retval) + goto cleanup; + memset(io, 0, sizeof(struct struct_io_channel)); + + io->magic = EXT2_ET_MAGIC_IO_CHANNEL; + io->manager = inode_io_manager; + retval = ext2fs_get_mem(strlen(name)+1, &io->name); + if (retval) + goto cleanup; + + strcpy(io->name, name); + io->private_data = data; + io->block_size = 1024; + io->read_error = 0; + io->write_error = 0; + io->refcount = 1; + + open_flags = (flags & IO_FLAG_RW) ? EXT2_FILE_WRITE : 0; + retval = ext2fs_file_open2(data->fs, data->ino, + (data->flags & CHANNEL_HAS_INODE) ? + &data->inode : 0, open_flags, + &data->file); + if (retval) + goto cleanup; + + *channel = io; + return 0; + +cleanup: + if (io && io->name) + ext2fs_free_mem(&io->name); + if (data) + ext2fs_free_mem(&data); + if (io) + ext2fs_free_mem(&io); + return retval; +} + +static errcode_t inode_close(io_channel channel) +{ + struct inode_private_data *data; + errcode_t retval = 0; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + if (--channel->refcount > 0) + return 0; + + retval = ext2fs_file_close(data->file); + + ext2fs_free_mem(&channel->private_data); + if (channel->name) + ext2fs_free_mem(&channel->name); + ext2fs_free_mem(&channel); + return retval; +} + +static errcode_t inode_set_blksize(io_channel channel, int blksize) +{ + struct inode_private_data *data; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + channel->block_size = blksize; + return 0; +} + + +static errcode_t inode_read_blk64(io_channel channel, + unsigned long long block, int count, void *buf) +{ + struct inode_private_data *data; + errcode_t retval; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + if ((retval = ext2fs_file_llseek(data->file, + (ext2_off64_t)(block * channel->block_size), + EXT2_SEEK_SET, 0))) + return retval; + + count = (count < 0) ? -count : (count * channel->block_size); + + return ext2fs_file_read(data->file, buf, count, 0); +} + +static errcode_t inode_read_blk(io_channel channel, unsigned long block, + int count, void *buf) +{ + return inode_read_blk64(channel, block, count, buf); +} + +static errcode_t inode_write_blk64(io_channel channel, + unsigned long long block, int count, const void *buf) +{ + struct inode_private_data *data; + errcode_t retval; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + if ((retval = ext2fs_file_llseek(data->file, + (ext2_off64_t) (block * channel->block_size), + EXT2_SEEK_SET, 0))) + return retval; + + count = (count < 0) ? -count : (count * channel->block_size); + + return ext2fs_file_write(data->file, buf, count, 0); +} + +static errcode_t inode_write_blk(io_channel channel, unsigned long block, + int count, const void *buf) +{ + return inode_write_blk64(channel, block, count, buf); +} + +static errcode_t inode_write_byte(io_channel channel, unsigned long offset, + int size, const void *buf) +{ + struct inode_private_data *data; + errcode_t retval = 0; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + if ((retval = ext2fs_file_lseek(data->file, offset, + EXT2_SEEK_SET, 0))) + return retval; + + return ext2fs_file_write(data->file, buf, size, 0); +} + +/* + * Flush data buffers to disk. + */ +static errcode_t inode_flush(io_channel channel) +{ + struct inode_private_data *data; + + EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL); + data = (struct inode_private_data *) channel->private_data; + EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_INODE_IO_CHANNEL); + + return ext2fs_file_flush(data->file); +} + |