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Diffstat (limited to 'e2fsprogs/old_e2fsprogs/ext2fs/imager.c')
-rw-r--r--e2fsprogs/old_e2fsprogs/ext2fs/imager.c377
1 files changed, 377 insertions, 0 deletions
diff --git a/e2fsprogs/old_e2fsprogs/ext2fs/imager.c b/e2fsprogs/old_e2fsprogs/ext2fs/imager.c
new file mode 100644
index 0000000..e82321e
--- /dev/null
+++ b/e2fsprogs/old_e2fsprogs/ext2fs/imager.c
@@ -0,0 +1,377 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * image.c --- writes out the critical parts of the filesystem as a
+ * flat file.
+ *
+ * Copyright (C) 2000 Theodore Ts'o.
+ *
+ * Note: this uses the POSIX IO interfaces, unlike most of the other
+ * functions in this library. So sue me.
+ *
+ * %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
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <fcntl.h>
+#include <time.h>
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+#ifndef HAVE_TYPE_SSIZE_T
+typedef int ssize_t;
+#endif
+
+/*
+ * This function returns 1 if the specified block is all zeros
+ */
+static int check_zero_block(char *buf, int blocksize)
+{
+ char *cp = buf;
+ int left = blocksize;
+
+ while (left > 0) {
+ if (*cp++)
+ return 0;
+ left--;
+ }
+ return 1;
+}
+
+/*
+ * Write the inode table out as a single block.
+ */
+#define BUF_BLOCKS 32
+
+errcode_t ext2fs_image_inode_write(ext2_filsys fs, int fd, int flags)
+{
+ unsigned int group, left, c, d;
+ char *buf, *cp;
+ blk_t blk;
+ ssize_t actual;
+ errcode_t retval;
+
+ buf = xmalloc(fs->blocksize * BUF_BLOCKS);
+
+ for (group = 0; group < fs->group_desc_count; group++) {
+ blk = fs->group_desc[(unsigned)group].bg_inode_table;
+ if (!blk)
+ return EXT2_ET_MISSING_INODE_TABLE;
+ left = fs->inode_blocks_per_group;
+ while (left) {
+ c = BUF_BLOCKS;
+ if (c > left)
+ c = left;
+ retval = io_channel_read_blk(fs->io, blk, c, buf);
+ if (retval)
+ goto errout;
+ cp = buf;
+ while (c) {
+ if (!(flags & IMAGER_FLAG_SPARSEWRITE)) {
+ d = c;
+ goto skip_sparse;
+ }
+ /* Skip zero blocks */
+ if (check_zero_block(cp, fs->blocksize)) {
+ c--;
+ blk++;
+ left--;
+ cp += fs->blocksize;
+ lseek(fd, fs->blocksize, SEEK_CUR);
+ continue;
+ }
+ /* Find non-zero blocks */
+ for (d=1; d < c; d++) {
+ if (check_zero_block(cp + d*fs->blocksize, fs->blocksize))
+ break;
+ }
+ skip_sparse:
+ actual = write(fd, cp, fs->blocksize * d);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != (ssize_t) (fs->blocksize * d)) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+ blk += d;
+ left -= d;
+ cp += fs->blocksize * d;
+ c -= d;
+ }
+ }
+ }
+ retval = 0;
+
+errout:
+ free(buf);
+ return retval;
+}
+
+/*
+ * Read in the inode table and stuff it into place
+ */
+errcode_t ext2fs_image_inode_read(ext2_filsys fs, int fd,
+ int flags EXT2FS_ATTR((unused)))
+{
+ unsigned int group, c, left;
+ char *buf;
+ blk_t blk;
+ ssize_t actual;
+ errcode_t retval;
+
+ buf = xmalloc(fs->blocksize * BUF_BLOCKS);
+
+ for (group = 0; group < fs->group_desc_count; group++) {
+ blk = fs->group_desc[(unsigned)group].bg_inode_table;
+ if (!blk) {
+ retval = EXT2_ET_MISSING_INODE_TABLE;
+ goto errout;
+ }
+ left = fs->inode_blocks_per_group;
+ while (left) {
+ c = BUF_BLOCKS;
+ if (c > left)
+ c = left;
+ actual = read(fd, buf, fs->blocksize * c);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != (ssize_t) (fs->blocksize * c)) {
+ retval = EXT2_ET_SHORT_READ;
+ goto errout;
+ }
+ retval = io_channel_write_blk(fs->io, blk, c, buf);
+ if (retval)
+ goto errout;
+
+ blk += c;
+ left -= c;
+ }
+ }
+ retval = ext2fs_flush_icache(fs);
+
+errout:
+ free(buf);
+ return retval;
+}
+
+/*
+ * Write out superblock and group descriptors
+ */
+errcode_t ext2fs_image_super_write(ext2_filsys fs, int fd,
+ int flags EXT2FS_ATTR((unused)))
+{
+ char *buf, *cp;
+ ssize_t actual;
+ errcode_t retval;
+
+ buf = xmalloc(fs->blocksize);
+
+ /*
+ * Write out the superblock
+ */
+ memset(buf, 0, fs->blocksize);
+ memcpy(buf, fs->super, SUPERBLOCK_SIZE);
+ actual = write(fd, buf, fs->blocksize);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != (ssize_t) fs->blocksize) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+
+ /*
+ * Now write out the block group descriptors
+ */
+ cp = (char *) fs->group_desc;
+ actual = write(fd, cp, fs->blocksize * fs->desc_blocks);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != (ssize_t) (fs->blocksize * fs->desc_blocks)) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+
+ retval = 0;
+
+errout:
+ free(buf);
+ return retval;
+}
+
+/*
+ * Read the superblock and group descriptors and overwrite them.
+ */
+errcode_t ext2fs_image_super_read(ext2_filsys fs, int fd,
+ int flags EXT2FS_ATTR((unused)))
+{
+ char *buf;
+ ssize_t actual, size;
+ errcode_t retval;
+
+ size = fs->blocksize * (fs->group_desc_count + 1);
+ buf = xmalloc(size);
+
+ /*
+ * Read it all in.
+ */
+ actual = read(fd, buf, size);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != size) {
+ retval = EXT2_ET_SHORT_READ;
+ goto errout;
+ }
+
+ /*
+ * Now copy in the superblock and group descriptors
+ */
+ memcpy(fs->super, buf, SUPERBLOCK_SIZE);
+
+ memcpy(fs->group_desc, buf + fs->blocksize,
+ fs->blocksize * fs->group_desc_count);
+
+ retval = 0;
+
+errout:
+ free(buf);
+ return retval;
+}
+
+/*
+ * Write the block/inode bitmaps.
+ */
+errcode_t ext2fs_image_bitmap_write(ext2_filsys fs, int fd, int flags)
+{
+ char *ptr;
+ int c, size;
+ char zero_buf[1024];
+ ssize_t actual;
+ errcode_t retval;
+
+ if (flags & IMAGER_FLAG_INODEMAP) {
+ if (!fs->inode_map) {
+ retval = ext2fs_read_inode_bitmap(fs);
+ if (retval)
+ return retval;
+ }
+ ptr = fs->inode_map->bitmap;
+ size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
+ } else {
+ if (!fs->block_map) {
+ retval = ext2fs_read_block_bitmap(fs);
+ if (retval)
+ return retval;
+ }
+ ptr = fs->block_map->bitmap;
+ size = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
+ }
+ size = size * fs->group_desc_count;
+
+ actual = write(fd, ptr, size);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != size) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+ size = size % fs->blocksize;
+ memset(zero_buf, 0, sizeof(zero_buf));
+ if (size) {
+ size = fs->blocksize - size;
+ while (size) {
+ c = size;
+ if (c > (int) sizeof(zero_buf))
+ c = sizeof(zero_buf);
+ actual = write(fd, zero_buf, c);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != c) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+ size -= c;
+ }
+ }
+ retval = 0;
+errout:
+ return retval;
+}
+
+
+/*
+ * Read the block/inode bitmaps.
+ */
+errcode_t ext2fs_image_bitmap_read(ext2_filsys fs, int fd, int flags)
+{
+ char *ptr, *buf = 0;
+ int size;
+ ssize_t actual;
+ errcode_t retval;
+
+ if (flags & IMAGER_FLAG_INODEMAP) {
+ if (!fs->inode_map) {
+ retval = ext2fs_read_inode_bitmap(fs);
+ if (retval)
+ return retval;
+ }
+ ptr = fs->inode_map->bitmap;
+ size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
+ } else {
+ if (!fs->block_map) {
+ retval = ext2fs_read_block_bitmap(fs);
+ if (retval)
+ return retval;
+ }
+ ptr = fs->block_map->bitmap;
+ size = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
+ }
+ size = size * fs->group_desc_count;
+
+ buf = xmalloc(size);
+
+ actual = read(fd, buf, size);
+ if (actual == -1) {
+ retval = errno;
+ goto errout;
+ }
+ if (actual != size) {
+ retval = EXT2_ET_SHORT_WRITE;
+ goto errout;
+ }
+ memcpy(ptr, buf, size);
+
+ retval = 0;
+errout:
+ free(buf);
+ return retval;
+}
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