Adding upstream version 1.47.0.upstream/1.47.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 470 insertions, 0 deletions

diff --git a/lib/ext2fs/imager.c b/lib/ext2fs/imager.c
new file mode 100644
index 0000000..23290a6
--- /dev/null
+++ b/lib/ext2fs/imager.c
@@ -0,0 +1,470 @@
+/*
+ * 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 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 <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)
+{
+	dgrp_t		group;
+	ssize_t		left, c, d;
+	char		*buf, *cp;
+	blk64_t		blk;
+	ssize_t		actual;
+	errcode_t	retval;
+	ext2_loff_t	r;
+
+	buf = malloc(fs->blocksize * BUF_BLOCKS);
+	if (!buf)
+		return ENOMEM;
+
+	for (group = 0; group < fs->group_desc_count; group++) {
+		blk = ext2fs_inode_table_loc(fs, group);
+		if (!blk) {
+			retval = EXT2_ET_MISSING_INODE_TABLE;
+			goto errout;
+		}
+		left = fs->inode_blocks_per_group;
+		if ((blk < fs->super->s_first_data_block) ||
+		    (blk + left - 1 >= ext2fs_blocks_count(fs->super))) {
+			retval = EXT2_ET_GDESC_BAD_INODE_TABLE;
+			goto errout;
+		}
+		while (left) {
+			c = BUF_BLOCKS;
+			if (c > left)
+				c = left;
+			retval = io_channel_read_blk64(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;
+					r = ext2fs_llseek(fd, fs->blocksize,
+							  SEEK_CUR);
+					if (r < 0) {
+						retval = errno;
+						goto errout;
+					}
+					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, d * fs->blocksize);
+				if (actual == -1) {
+					retval = errno;
+					goto errout;
+				}
+				if (actual != d * fs->blocksize) {
+					retval = EXT2_ET_SHORT_WRITE;
+					goto errout;
+				}
+				blk += d;
+				left -= d;
+				cp += d * fs->blocksize;
+				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)))
+{
+	dgrp_t		group;
+	ssize_t		c, left;
+	char		*buf;
+	blk64_t		blk;
+	ssize_t		actual;
+	errcode_t	retval;
+
+	buf = malloc(fs->blocksize * BUF_BLOCKS);
+	if (!buf)
+		return ENOMEM;
+
+	for (group = 0; group < fs->group_desc_count; group++) {
+		blk = ext2fs_inode_table_loc(fs, group);
+		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 != fs->blocksize * c) {
+				retval = EXT2_ET_SHORT_READ;
+				goto errout;
+			}
+			retval = io_channel_write_blk64(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;
+#ifdef WORDS_BIGENDIAN
+	unsigned int	groups_per_block;
+	struct		ext2_group_desc *gdp;
+	int		j;
+#endif
+
+	if (fs->group_desc == NULL)
+		return EXT2_ET_NO_GDESC;
+
+	buf = malloc(fs->blocksize);
+	if (!buf)
+		return ENOMEM;
+
+	/*
+	 * Write out the superblock
+	 */
+	memset(buf, 0, fs->blocksize);
+#ifdef WORDS_BIGENDIAN
+	/*
+	 * We're writing out superblock so let's convert
+	 * it to little endian and then back if needed
+	 */
+	ext2fs_swap_super(fs->super);
+	memcpy(buf, fs->super, SUPERBLOCK_SIZE);
+	ext2fs_swap_super(fs->super);
+#else
+	memcpy(buf, fs->super, SUPERBLOCK_SIZE);
+#endif
+	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;
+
+#ifdef WORDS_BIGENDIAN
+	/*
+	 * Convert group descriptors to little endian and back
+	 * if needed
+	 */
+	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
+	for (j=0; j < groups_per_block*fs->desc_blocks; j++) {
+		gdp = ext2fs_group_desc(fs, fs->group_desc, j);
+		if (gdp)
+			ext2fs_swap_group_desc2(fs, gdp);
+	}
+#endif
+
+	actual = write(fd, cp, (ssize_t)fs->blocksize * fs->desc_blocks);
+
+
+#ifdef WORDS_BIGENDIAN
+	groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
+	for (j=0; j < groups_per_block*fs->desc_blocks; j++) {
+		gdp = ext2fs_group_desc(fs, fs->group_desc, j);
+		if (gdp)
+			ext2fs_swap_group_desc2(fs, gdp);
+	}
+#endif
+
+	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 = (ssize_t)fs->blocksize * (fs->group_desc_count + 1);
+	buf = malloc(size);
+	if (!buf)
+		return ENOMEM;
+
+	/*
+	 * 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,
+	       (ssize_t)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)
+{
+	ext2fs_generic_bitmap	bmap;
+	errcode_t		retval;
+	ssize_t			actual;
+	size_t			c;
+	__u64			itr, cnt, size, total_size;
+	char			buf[1024];
+
+	if (flags & IMAGER_FLAG_INODEMAP) {
+		if (!fs->inode_map) {
+			retval = ext2fs_read_inode_bitmap(fs);
+			if (retval)
+				return retval;
+		}
+		bmap = fs->inode_map;
+		itr = 1;
+		cnt = (__u64)EXT2_INODES_PER_GROUP(fs->super) *
+			fs->group_desc_count;
+		size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
+	} else {
+		if (!fs->block_map) {
+			retval = ext2fs_read_block_bitmap(fs);
+			if (retval)
+				return retval;
+		}
+		bmap = fs->block_map;
+		itr = fs->super->s_first_data_block;
+		cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super, fs->group_desc_count);
+		size = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
+	}
+	total_size = size * fs->group_desc_count;
+
+	while (cnt > 0) {
+		size = sizeof(buf);
+		if (size > (cnt >> 3))
+			size = (cnt >> 3);
+		if (size == 0)
+			break;
+
+		retval = ext2fs_get_generic_bmap_range(bmap, itr,
+						       size << 3, buf);
+		if (retval)
+			return retval;
+
+		actual = write(fd, buf, size);
+		if (actual == -1)
+			return errno;
+		if (actual != (int) size)
+			return EXT2_ET_SHORT_READ;
+
+		itr += size << 3;
+		cnt -= size << 3;
+	}
+
+	size = total_size % fs->blocksize;
+	memset(buf, 0, sizeof(buf));
+	if (size) {
+		size = fs->blocksize - size;
+		while (size) {
+			c = size;
+			if (c > (int) sizeof(buf))
+				c = sizeof(buf);
+			actual = write(fd, buf, c);
+			if (actual < 0)
+				return errno;
+			if ((size_t) actual != c)
+				return EXT2_ET_SHORT_WRITE;
+			size -= c;
+		}
+	}
+	return 0;
+}
+
+
+/*
+ * Read the block/inode bitmaps.
+ */
+errcode_t ext2fs_image_bitmap_read(ext2_filsys fs, int fd, int flags)
+{
+	ext2fs_generic_bitmap	bmap;
+	errcode_t		retval;
+	__u64			itr, cnt;
+	char			buf[1024];
+	unsigned int		size;
+	ssize_t			actual;
+
+	if (flags & IMAGER_FLAG_INODEMAP) {
+		if (!fs->inode_map) {
+			retval = ext2fs_read_inode_bitmap(fs);
+			if (retval)
+				return retval;
+		}
+		bmap = fs->inode_map;
+		itr = 1;
+		cnt = (__u64)EXT2_INODES_PER_GROUP(fs->super) *
+			fs->group_desc_count;
+		size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
+	} else {
+		if (!fs->block_map) {
+			retval = ext2fs_read_block_bitmap(fs);
+			if (retval)
+				return retval;
+		}
+		bmap = fs->block_map;
+		itr = fs->super->s_first_data_block;
+		cnt = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count);
+		size = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
+	}
+
+	while (cnt > 0) {
+		size = sizeof(buf);
+		if (size > (cnt >> 3))
+			size = (cnt >> 3);
+		if (size == 0)
+			break;
+
+		actual = read(fd, buf, size);
+		if (actual == -1)
+			return errno;
+		if (actual != (int) size)
+			return EXT2_ET_SHORT_READ;
+
+		retval = ext2fs_set_generic_bmap_range(bmap, itr,
+						       size << 3, buf);
+		if (retval)
+			return retval;
+
+		itr += size << 3;
+		cnt -= size << 3;
+	}
+	return 0;
+}