import ext2fs lib to prep for new e2fsprogs

1 files changed, 300 insertions, 0 deletions

diff --git a/e2fsprogs/ext2fs/rw_bitmaps.c b/e2fsprogs/ext2fs/rw_bitmaps.c
new file mode 100644
index 0000000..b67a925
--- /dev/null
+++ b/e2fsprogs/ext2fs/rw_bitmaps.c
@@ -0,0 +1,300 @@
+/*
+ * rw_bitmaps.c --- routines to read and write the  inode and block bitmaps.
+ *
+ * Copyright (C) 1993, 1994, 1994, 1996 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 <fcntl.h>
+#include <time.h>
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+#include "e2image.h"
+
+#if defined(__powerpc__) && defined(EXT2FS_ENABLE_SWAPFS)
+/*
+ * On the PowerPC, the big-endian variant of the ext2 filesystem
+ * has its bitmaps stored as 32-bit words with bit 0 as the LSB
+ * of each word.  Thus a bitmap with only bit 0 set would be, as
+ * a string of bytes, 00 00 00 01 00 ...
+ * To cope with this, we byte-reverse each word of a bitmap if
+ * we have a big-endian filesystem, that is, if we are *not*
+ * byte-swapping other word-sized numbers.
+ */
+#define EXT2_BIG_ENDIAN_BITMAPS
+#endif
+
+#ifdef EXT2_BIG_ENDIAN_BITMAPS
+static void ext2fs_swap_bitmap(ext2_filsys fs, char *bitmap, int nbytes)
+{
+	__u32 *p = (__u32 *) bitmap;
+	int n;
+		
+	for (n = nbytes / sizeof(__u32); n > 0; --n, ++p)
+		*p = ext2fs_swab32(*p);
+}
+#endif
+
+errcode_t ext2fs_write_inode_bitmap(ext2_filsys fs)
+{
+	dgrp_t 		i;
+	size_t		nbytes;
+	errcode_t	retval;
+	char * inode_bitmap = fs->inode_map->bitmap;
+	char * bitmap_block = NULL;
+	blk_t		blk;
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	if (!(fs->flags & EXT2_FLAG_RW))
+		return EXT2_ET_RO_FILSYS;
+	if (!inode_bitmap)
+		return 0;
+	nbytes = (size_t) ((EXT2_INODES_PER_GROUP(fs->super)+7) / 8);
+	
+	retval = ext2fs_get_mem(fs->blocksize, &bitmap_block);
+	if (retval)
+		return retval;
+	memset(bitmap_block, 0xff, fs->blocksize);
+	for (i = 0; i < fs->group_desc_count; i++) {
+		memcpy(bitmap_block, inode_bitmap, nbytes);
+		blk = fs->group_desc[i].bg_inode_bitmap;
+		if (blk) {
+#ifdef EXT2_BIG_ENDIAN_BITMAPS
+			if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+			      (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)))
+				ext2fs_swap_bitmap(fs, bitmap_block, nbytes);
+#endif
+			retval = io_channel_write_blk(fs->io, blk, 1,
+						      bitmap_block);
+			if (retval)
+				return EXT2_ET_INODE_BITMAP_WRITE;
+		}
+		inode_bitmap += nbytes;
+	}
+	fs->flags &= ~EXT2_FLAG_IB_DIRTY;
+	ext2fs_free_mem(&bitmap_block);
+	return 0;
+}
+
+errcode_t ext2fs_write_block_bitmap (ext2_filsys fs)
+{
+	dgrp_t 		i;
+	unsigned int	j;
+	int		nbytes;
+	unsigned int	nbits;
+	errcode_t	retval;
+	char * block_bitmap = fs->block_map->bitmap;
+	char * bitmap_block = NULL;
+	blk_t		blk;
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	if (!(fs->flags & EXT2_FLAG_RW))
+		return EXT2_ET_RO_FILSYS;
+	if (!block_bitmap)
+		return 0;
+	nbytes = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
+	retval = ext2fs_get_mem(fs->blocksize, &bitmap_block);
+	if (retval)
+		return retval;
+	memset(bitmap_block, 0xff, fs->blocksize);
+	for (i = 0; i < fs->group_desc_count; i++) {
+		memcpy(bitmap_block, block_bitmap, nbytes);
+		if (i == fs->group_desc_count - 1) {
+			/* Force bitmap padding for the last group */
+			nbits = ((fs->super->s_blocks_count
+				  - fs->super->s_first_data_block)
+				 % EXT2_BLOCKS_PER_GROUP(fs->super));
+			if (nbits)
+				for (j = nbits; j < fs->blocksize * 8; j++)
+					ext2fs_set_bit(j, bitmap_block);
+		}
+		blk = fs->group_desc[i].bg_block_bitmap;
+		if (blk) {
+#ifdef EXT2_BIG_ENDIAN_BITMAPS
+			if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+			      (fs->flags & EXT2_FLAG_SWAP_BYTES_WRITE)))
+				ext2fs_swap_bitmap(fs, bitmap_block, nbytes);
+#endif
+			retval = io_channel_write_blk(fs->io, blk, 1,
+						      bitmap_block);
+			if (retval)
+				return EXT2_ET_BLOCK_BITMAP_WRITE;
+		}
+		block_bitmap += nbytes;
+	}
+	fs->flags &= ~EXT2_FLAG_BB_DIRTY;
+	ext2fs_free_mem(&bitmap_block);
+	return 0;
+}
+
+static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block)
+{
+	dgrp_t i;
+	char *block_bitmap = 0, *inode_bitmap = 0;
+	char *buf;
+	errcode_t retval;
+	int block_nbytes = (int) EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
+	int inode_nbytes = (int) EXT2_INODES_PER_GROUP(fs->super) / 8;
+	blk_t	blk;
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	fs->write_bitmaps = ext2fs_write_bitmaps;
+
+	retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf);
+	if (retval)
+		return retval;
+	if (do_block) {
+		if (fs->block_map)
+			ext2fs_free_block_bitmap(fs->block_map);
+		sprintf(buf, "block bitmap for %s", fs->device_name);
+		retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map);
+		if (retval)
+			goto cleanup;
+		block_bitmap = fs->block_map->bitmap;
+	}
+	if (do_inode) {
+		if (fs->inode_map)
+			ext2fs_free_inode_bitmap(fs->inode_map);
+		sprintf(buf, "inode bitmap for %s", fs->device_name);
+		retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map);
+		if (retval)
+			goto cleanup;
+		inode_bitmap = fs->inode_map->bitmap;
+	}
+	ext2fs_free_mem(&buf);
+
+	if (fs->flags & EXT2_FLAG_IMAGE_FILE) {
+		if (inode_bitmap) {
+			blk = (fs->image_header->offset_inodemap /
+			       fs->blocksize);
+			retval = io_channel_read_blk(fs->image_io, blk,
+			     -(inode_nbytes * fs->group_desc_count),
+			     inode_bitmap);
+			if (retval)
+				goto cleanup;
+		}
+		if (block_bitmap) {
+			blk = (fs->image_header->offset_blockmap /
+			       fs->blocksize);
+			retval = io_channel_read_blk(fs->image_io, blk, 
+			     -(block_nbytes * fs->group_desc_count),
+			     block_bitmap);
+			if (retval)
+				goto cleanup;
+		}
+		return 0;
+	}
+
+	for (i = 0; i < fs->group_desc_count; i++) {
+		if (block_bitmap) {
+			blk = fs->group_desc[i].bg_block_bitmap;
+			if (blk) {
+				retval = io_channel_read_blk(fs->io, blk,
+					     -block_nbytes, block_bitmap);
+				if (retval) {
+					retval = EXT2_ET_BLOCK_BITMAP_READ;
+					goto cleanup;
+				}
+#ifdef EXT2_BIG_ENDIAN_BITMAPS
+				if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+				      (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)))
+					ext2fs_swap_bitmap(fs, block_bitmap, block_nbytes);
+#endif
+			} else
+				memset(block_bitmap, 0, block_nbytes);
+			block_bitmap += block_nbytes;
+		}
+		if (inode_bitmap) {
+			blk = fs->group_desc[i].bg_inode_bitmap;
+			if (blk) {
+				retval = io_channel_read_blk(fs->io, blk,
+					     -inode_nbytes, inode_bitmap);
+				if (retval) {
+					retval = EXT2_ET_INODE_BITMAP_READ;
+					goto cleanup;
+				}
+#ifdef EXT2_BIG_ENDIAN_BITMAPS
+				if (!((fs->flags & EXT2_FLAG_SWAP_BYTES) ||
+				      (fs->flags & EXT2_FLAG_SWAP_BYTES_READ)))
+					ext2fs_swap_bitmap(fs, inode_bitmap, inode_nbytes);
+#endif
+			} else
+				memset(inode_bitmap, 0, inode_nbytes);
+			inode_bitmap += inode_nbytes;
+		}
+	}
+	return 0;
+	
+cleanup:
+	if (do_block) {
+		ext2fs_free_mem(&fs->block_map);
+		fs->block_map = 0;
+	}
+	if (do_inode) {
+		ext2fs_free_mem(&fs->inode_map);
+		fs->inode_map = 0;
+	}
+	if (buf)
+		ext2fs_free_mem(&buf);
+	return retval;
+}
+
+errcode_t ext2fs_read_inode_bitmap (ext2_filsys fs)
+{
+	return read_bitmaps(fs, 1, 0);
+}
+
+errcode_t ext2fs_read_block_bitmap(ext2_filsys fs)
+{
+	return read_bitmaps(fs, 0, 1);
+}
+
+errcode_t ext2fs_read_bitmaps(ext2_filsys fs)
+{
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	if (fs->inode_map && fs->block_map)
+		return 0;
+
+	return read_bitmaps(fs, !fs->inode_map, !fs->block_map);
+}
+
+errcode_t ext2fs_write_bitmaps(ext2_filsys fs)
+{
+	errcode_t	retval;
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	if (fs->block_map && ext2fs_test_bb_dirty(fs)) {
+		retval = ext2fs_write_block_bitmap(fs);
+		if (retval)
+			return retval;
+	}
+	if (fs->inode_map && ext2fs_test_ib_dirty(fs)) {
+		retval = ext2fs_write_inode_bitmap(fs);
+		if (retval)
+			return retval;
+	}
+	return 0;
+}	
+