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Diffstat (limited to 'e2fsprogs/ext2fs/fileio.c')
-rw-r--r--e2fsprogs/ext2fs/fileio.c377
1 files changed, 0 insertions, 377 deletions
diff --git a/e2fsprogs/ext2fs/fileio.c b/e2fsprogs/ext2fs/fileio.c
deleted file mode 100644
index c56a21a..0000000
--- a/e2fsprogs/ext2fs/fileio.c
+++ /dev/null
@@ -1,377 +0,0 @@
-/* vi: set sw=4 ts=4: */
-/*
- * fileio.c --- Simple file I/O routines
- *
- * Copyright (C) 1997 Theodore Ts'o.
- *
- * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
- * %End-Header%
- */
-
-#include <stdio.h>
-#include <string.h>
-#if HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-#include "ext2_fs.h"
-#include "ext2fs.h"
-
-struct ext2_file {
- errcode_t magic;
- ext2_filsys fs;
- ext2_ino_t ino;
- struct ext2_inode inode;
- int flags;
- __u64 pos;
- blk_t blockno;
- blk_t physblock;
- char *buf;
-};
-
-#define BMAP_BUFFER (file->buf + fs->blocksize)
-
-errcode_t ext2fs_file_open2(ext2_filsys fs, ext2_ino_t ino,
- struct ext2_inode *inode,
- int flags, ext2_file_t *ret)
-{
- ext2_file_t file;
- errcode_t retval;
-
- /*
- * Don't let caller create or open a file for writing if the
- * filesystem is read-only.
- */
- if ((flags & (EXT2_FILE_WRITE | EXT2_FILE_CREATE)) &&
- !(fs->flags & EXT2_FLAG_RW))
- return EXT2_ET_RO_FILSYS;
-
- retval = ext2fs_get_mem(sizeof(struct ext2_file), &file);
- if (retval)
- return retval;
-
- memset(file, 0, sizeof(struct ext2_file));
- file->magic = EXT2_ET_MAGIC_EXT2_FILE;
- file->fs = fs;
- file->ino = ino;
- file->flags = flags & EXT2_FILE_MASK;
-
- if (inode) {
- memcpy(&file->inode, inode, sizeof(struct ext2_inode));
- } else {
- retval = ext2fs_read_inode(fs, ino, &file->inode);
- if (retval)
- goto fail;
- }
-
- retval = ext2fs_get_mem(fs->blocksize * 3, &file->buf);
- if (retval)
- goto fail;
-
- *ret = file;
- return 0;
-
-fail:
- ext2fs_free_mem(&file->buf);
- ext2fs_free_mem(&file);
- return retval;
-}
-
-errcode_t ext2fs_file_open(ext2_filsys fs, ext2_ino_t ino,
- int flags, ext2_file_t *ret)
-{
- return ext2fs_file_open2(fs, ino, NULL, flags, ret);
-}
-
-/*
- * This function returns the filesystem handle of a file from the structure
- */
-ext2_filsys ext2fs_file_get_fs(ext2_file_t file)
-{
- if (file->magic != EXT2_ET_MAGIC_EXT2_FILE)
- return 0;
- return file->fs;
-}
-
-/*
- * This function flushes the dirty block buffer out to disk if
- * necessary.
- */
-errcode_t ext2fs_file_flush(ext2_file_t file)
-{
- errcode_t retval;
- ext2_filsys fs;
-
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
- fs = file->fs;
-
- if (!(file->flags & EXT2_FILE_BUF_VALID) ||
- !(file->flags & EXT2_FILE_BUF_DIRTY))
- return 0;
-
- /*
- * OK, the physical block hasn't been allocated yet.
- * Allocate it.
- */
- if (!file->physblock) {
- retval = ext2fs_bmap(fs, file->ino, &file->inode,
- BMAP_BUFFER, file->ino ? BMAP_ALLOC : 0,
- file->blockno, &file->physblock);
- if (retval)
- return retval;
- }
-
- retval = io_channel_write_blk(fs->io, file->physblock,
- 1, file->buf);
- if (retval)
- return retval;
-
- file->flags &= ~EXT2_FILE_BUF_DIRTY;
-
- return retval;
-}
-
-/*
- * This function synchronizes the file's block buffer and the current
- * file position, possibly invalidating block buffer if necessary
- */
-static errcode_t sync_buffer_position(ext2_file_t file)
-{
- blk_t b;
- errcode_t retval;
-
- b = file->pos / file->fs->blocksize;
- if (b != file->blockno) {
- retval = ext2fs_file_flush(file);
- if (retval)
- return retval;
- file->flags &= ~EXT2_FILE_BUF_VALID;
- }
- file->blockno = b;
- return 0;
-}
-
-/*
- * This function loads the file's block buffer with valid data from
- * the disk as necessary.
- *
- * If dontfill is true, then skip initializing the buffer since we're
- * going to be replacing its entire contents anyway. If set, then the
- * function basically only sets file->physblock and EXT2_FILE_BUF_VALID
- */
-#define DONTFILL 1
-static errcode_t load_buffer(ext2_file_t file, int dontfill)
-{
- ext2_filsys fs = file->fs;
- errcode_t retval;
-
- if (!(file->flags & EXT2_FILE_BUF_VALID)) {
- retval = ext2fs_bmap(fs, file->ino, &file->inode,
- BMAP_BUFFER, 0, file->blockno,
- &file->physblock);
- if (retval)
- return retval;
- if (!dontfill) {
- if (file->physblock) {
- retval = io_channel_read_blk(fs->io,
- file->physblock,
- 1, file->buf);
- if (retval)
- return retval;
- } else
- memset(file->buf, 0, fs->blocksize);
- }
- file->flags |= EXT2_FILE_BUF_VALID;
- }
- return 0;
-}
-
-
-errcode_t ext2fs_file_close(ext2_file_t file)
-{
- errcode_t retval;
-
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
-
- retval = ext2fs_file_flush(file);
-
- ext2fs_free_mem(&file->buf);
- ext2fs_free_mem(&file);
-
- return retval;
-}
-
-
-errcode_t ext2fs_file_read(ext2_file_t file, void *buf,
- unsigned int wanted, unsigned int *got)
-{
- ext2_filsys fs;
- errcode_t retval = 0;
- unsigned int start, c, count = 0;
- __u64 left;
- char *ptr = (char *) buf;
-
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
- fs = file->fs;
-
- while ((file->pos < EXT2_I_SIZE(&file->inode)) && (wanted > 0)) {
- retval = sync_buffer_position(file);
- if (retval)
- goto fail;
- retval = load_buffer(file, 0);
- if (retval)
- goto fail;
-
- start = file->pos % fs->blocksize;
- c = fs->blocksize - start;
- if (c > wanted)
- c = wanted;
- left = EXT2_I_SIZE(&file->inode) - file->pos ;
- if (c > left)
- c = left;
-
- memcpy(ptr, file->buf+start, c);
- file->pos += c;
- ptr += c;
- count += c;
- wanted -= c;
- }
-
-fail:
- if (got)
- *got = count;
- return retval;
-}
-
-
-errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
- unsigned int nbytes, unsigned int *written)
-{
- ext2_filsys fs;
- errcode_t retval = 0;
- unsigned int start, c, count = 0;
- const char *ptr = (const char *) buf;
-
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
- fs = file->fs;
-
- if (!(file->flags & EXT2_FILE_WRITE))
- return EXT2_ET_FILE_RO;
-
- while (nbytes > 0) {
- retval = sync_buffer_position(file);
- if (retval)
- goto fail;
-
- start = file->pos % fs->blocksize;
- c = fs->blocksize - start;
- if (c > nbytes)
- c = nbytes;
-
- /*
- * We only need to do a read-modify-update cycle if
- * we're doing a partial write.
- */
- retval = load_buffer(file, (c == fs->blocksize));
- if (retval)
- goto fail;
-
- file->flags |= EXT2_FILE_BUF_DIRTY;
- memcpy(file->buf+start, ptr, c);
- file->pos += c;
- ptr += c;
- count += c;
- nbytes -= c;
- }
-
-fail:
- if (written)
- *written = count;
- return retval;
-}
-
-errcode_t ext2fs_file_llseek(ext2_file_t file, __u64 offset,
- int whence, __u64 *ret_pos)
-{
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
-
- if (whence == EXT2_SEEK_SET)
- file->pos = offset;
- else if (whence == EXT2_SEEK_CUR)
- file->pos += offset;
- else if (whence == EXT2_SEEK_END)
- file->pos = EXT2_I_SIZE(&file->inode) + offset;
- else
- return EXT2_ET_INVALID_ARGUMENT;
-
- if (ret_pos)
- *ret_pos = file->pos;
-
- return 0;
-}
-
-errcode_t ext2fs_file_lseek(ext2_file_t file, ext2_off_t offset,
- int whence, ext2_off_t *ret_pos)
-{
- __u64 loffset, ret_loffset;
- errcode_t retval;
-
- loffset = offset;
- retval = ext2fs_file_llseek(file, loffset, whence, &ret_loffset);
- if (ret_pos)
- *ret_pos = (ext2_off_t) ret_loffset;
- return retval;
-}
-
-
-/*
- * This function returns the size of the file, according to the inode
- */
-errcode_t ext2fs_file_get_lsize(ext2_file_t file, __u64 *ret_size)
-{
- if (file->magic != EXT2_ET_MAGIC_EXT2_FILE)
- return EXT2_ET_MAGIC_EXT2_FILE;
- *ret_size = EXT2_I_SIZE(&file->inode);
- return 0;
-}
-
-/*
- * This function returns the size of the file, according to the inode
- */
-ext2_off_t ext2fs_file_get_size(ext2_file_t file)
-{
- __u64 size;
-
- if (ext2fs_file_get_lsize(file, &size))
- return 0;
- if ((size >> 32) != 0)
- return 0;
- return size;
-}
-
-/*
- * This function sets the size of the file, truncating it if necessary
- *
- * XXX still need to call truncate
- */
-errcode_t ext2fs_file_set_size(ext2_file_t file, ext2_off_t size)
-{
- errcode_t retval;
- EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
-
- file->inode.i_size = size;
- file->inode.i_size_high = 0;
- if (file->ino) {
- retval = ext2fs_write_inode(file->fs, file->ino, &file->inode);
- if (retval)
- return retval;
- }
-
- /*
- * XXX truncate inode if necessary
- */
-
- return 0;
-}
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