/src/e2fsprogs/lib/ext2fs/imager.c

Source
/*
 * 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->desc_blocks + 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->desc_blocks);

  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;
}

Coverage Report

Created: 2026-10-23 07:00

Line	Count	Source
1		/*
2		* image.c --- writes out the critical parts of the filesystem as a
3		* flat file.
4		*
5		* Copyright (C) 2000 Theodore Ts'o.
6		*
7		* Note: this uses the POSIX IO interfaces, unlike most of the other
8		* functions in this library. So sue me.
9		*
10		* %Begin-Header%
11		* This file may be redistributed under the terms of the GNU Library
12		* General Public License, version 2.
13		* %End-Header%
14		*/
15
16		#include "config.h"
17		#include <stdio.h>
18		#include <string.h>
19		#if HAVE_UNISTD_H
20		#include <unistd.h>
21		#endif
22		#if HAVE_ERRNO_H
23		#include <errno.h>
24		#endif
25		#include <fcntl.h>
26		#include <time.h>
27		#if HAVE_SYS_STAT_H
28		#include <sys/stat.h>
29		#endif
30		#if HAVE_SYS_TYPES_H
31		#include <sys/types.h>
32		#endif
33
34		#include "ext2_fs.h"
35		#include "ext2fs.h"
36
37		#ifndef HAVE_TYPE_SSIZE_T
38		typedef int ssize_t;
39		#endif
40
41		/*
42		* This function returns 1 if the specified block is all zeros
43		*/
44		static int check_zero_block(char *buf, int blocksize)
45	0	{
46	0	char *cp = buf;
47	0	int left = blocksize;
48
49	0	while (left > 0) {
50	0	if (*cp++)
51	0	return 0;
52	0	left--;
53	0	}
54	0	return 1;
55	0	}
56
57		/*
58		* Write the inode table out as a single block.
59		*/
60	2.95k	#define BUF_BLOCKS 32
61
62		errcode_t ext2fs_image_inode_write(ext2_filsys fs, int fd, int flags)
63	124	{
64	124	dgrp_t group;
65	124	ssize_t left, c, d;
66	124	char buf, cp;
67	124	blk64_t blk;
68	124	ssize_t actual;
69	124	errcode_t retval;
70	124	ext2_loff_t r;
71
72	124	buf = malloc(fs->blocksize * BUF_BLOCKS);
73	124	if (!buf)
74	0	return ENOMEM;
75
76	2.10k	for (group = 0; group < fs->group_desc_count; group++) {
77	2.08k	blk = ext2fs_inode_table_loc(fs, group);
78	2.08k	if (!blk) {
79	5	retval = EXT2_ET_MISSING_INODE_TABLE;
80	5	goto errout;
81	5	}
82	2.08k	left = fs->inode_blocks_per_group;
83	2.08k	if ((blk < fs->super->s_first_data_block) \|\|
84	2.08k	(blk + left - 1 >= ext2fs_blocks_count(fs->super))) {
85	76	retval = EXT2_ET_GDESC_BAD_INODE_TABLE;
86	76	goto errout;
87	76	}
88	4.80k	while (left) {
89	2.82k	c = BUF_BLOCKS;
90	2.82k	if (c > left)
91	1.86k	c = left;
92	2.82k	retval = io_channel_read_blk64(fs->io, blk, c, buf);
93	2.82k	if (retval)
94	27	goto errout;
95	2.79k	cp = buf;
96	5.59k	while (c) {
97	2.79k	if (!(flags & IMAGER_FLAG_SPARSEWRITE)) {
98	2.79k	d = c;
99	2.79k	goto skip_sparse;
100	2.79k	}
101		/* Skip zero blocks */
102	0	if (check_zero_block(cp, fs->blocksize)) {
103	0	c--;
104	0	blk++;
105	0	left--;
106	0	cp += fs->blocksize;
107	0	r = ext2fs_llseek(fd, fs->blocksize,
108	0	SEEK_CUR);
109	0	if (r < 0) {
110	0	retval = errno;
111	0	goto errout;
112	0	}
113	0	continue;
114	0	}
115		/* Find non-zero blocks */
116	0	for (d = 1; d < c; d++) {
117	0	if (check_zero_block(cp +
118	0	d * fs->blocksize,
119	0	fs->blocksize))
120	0	break;
121	0	}
122	2.79k	skip_sparse:
123	2.79k	actual = write(fd, cp, d * fs->blocksize);
124	2.79k	if (actual == -1) {
125	0	retval = errno;
126	0	goto errout;
127	0	}
128	2.79k	if (actual != d * fs->blocksize) {
129	0	retval = EXT2_ET_SHORT_WRITE;
130	0	goto errout;
131	0	}
132	2.79k	blk += d;
133	2.79k	left -= d;
134	2.79k	cp += d * fs->blocksize;
135	2.79k	c -= d;
136	2.79k	}
137	2.79k	}
138	2.00k	}
139	16	retval = 0;
140
141	124	errout:
142	124	free(buf);
143	124	return retval;
144	16	}
145
146		/*
147		* Read in the inode table and stuff it into place
148		*/
149		errcode_t ext2fs_image_inode_read(ext2_filsys fs, int fd,
150		int flags EXT2FS_ATTR((unused)))
151	3	{
152	3	dgrp_t group;
153	3	ssize_t c, left;
154	3	char *buf;
155	3	blk64_t blk;
156	3	ssize_t actual;
157	3	errcode_t retval;
158
159	3	buf = malloc(fs->blocksize * BUF_BLOCKS);
160	3	if (!buf)
161	0	return ENOMEM;
162
163	68	for (group = 0; group < fs->group_desc_count; group++) {
164	67	blk = ext2fs_inode_table_loc(fs, group);
165	67	if (!blk) {
166	1	retval = EXT2_ET_MISSING_INODE_TABLE;
167	1	goto errout;
168	1	}
169	66	left = fs->inode_blocks_per_group;
170	66	while (left) {
171	1	c = BUF_BLOCKS;
172	1	if (c > left)
173	0	c = left;
174	1	actual = read(fd, buf, fs->blocksize * c);
175	1	if (actual == -1) {
176	0	retval = errno;
177	0	goto errout;
178	0	}
179	1	if (actual != fs->blocksize * c) {
180	1	retval = EXT2_ET_SHORT_READ;
181	1	goto errout;
182	1	}
183	0	retval = io_channel_write_blk64(fs->io, blk, c, buf);
184	0	if (retval)
185	0	goto errout;
186
187	0	blk += c;
188	0	left -= c;
189	0	}
190	66	}
191	1	retval = ext2fs_flush_icache(fs);
192
193	3	errout:
194	3	free(buf);
195	3	return retval;
196	1	}
197
198		/*
199		* Write out superblock and group descriptors
200		*/
201		errcode_t ext2fs_image_super_write(ext2_filsys fs, int fd,
202		int flags EXT2FS_ATTR((unused)))
203	8	{
204	8	char buf, cp;
205	8	ssize_t actual;
206	8	errcode_t retval;
207		#ifdef WORDS_BIGENDIAN
208		unsigned int groups_per_block;
209		struct ext2_group_desc *gdp;
210		int j;
211		#endif
212
213	8	if (fs->group_desc == NULL)
214	0	return EXT2_ET_NO_GDESC;
215
216	8	buf = malloc(fs->blocksize);
217	8	if (!buf)
218	0	return ENOMEM;
219
220		/*
221		* Write out the superblock
222		*/
223	8	memset(buf, 0, fs->blocksize);
224		#ifdef WORDS_BIGENDIAN
225		/*
226		* We're writing out superblock so let's convert
227		* it to little endian and then back if needed
228		*/
229		ext2fs_swap_super(fs->super);
230		memcpy(buf, fs->super, SUPERBLOCK_SIZE);
231		ext2fs_swap_super(fs->super);
232		#else
233	8	memcpy(buf, fs->super, SUPERBLOCK_SIZE);
234	8	#endif
235	8	actual = write(fd, buf, fs->blocksize);
236	8	if (actual == -1) {
237	0	retval = errno;
238	0	goto errout;
239	0	}
240	8	if (actual != (ssize_t) fs->blocksize) {
241	0	retval = EXT2_ET_SHORT_WRITE;
242	0	goto errout;
243	0	}
244
245		/*
246		* Now write out the block group descriptors
247		*/
248
249	8	cp = (char *) fs->group_desc;
250
251		#ifdef WORDS_BIGENDIAN
252		/*
253		* Convert group descriptors to little endian and back
254		* if needed
255		*/
256		groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
257		for (j=0; j < groups_per_block*fs->desc_blocks; j++) {
258		gdp = ext2fs_group_desc(fs, fs->group_desc, j);
259		if (gdp)
260		ext2fs_swap_group_desc2(fs, gdp);
261		}
262		#endif
263
264	8	actual = write(fd, cp, (ssize_t)fs->blocksize * fs->desc_blocks);
265
266
267		#ifdef WORDS_BIGENDIAN
268		groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
269		for (j=0; j < groups_per_block*fs->desc_blocks; j++) {
270		gdp = ext2fs_group_desc(fs, fs->group_desc, j);
271		if (gdp)
272		ext2fs_swap_group_desc2(fs, gdp);
273		}
274		#endif
275
276	8	if (actual == -1) {
277	0	retval = errno;
278	0	goto errout;
279	0	}
280	8	if (actual != (ssize_t)(fs->blocksize * fs->desc_blocks)) {
281	0	retval = EXT2_ET_SHORT_WRITE;
282	0	goto errout;
283	0	}
284
285	8	retval = 0;
286
287	8	errout:
288	8	free(buf);
289	8	return retval;
290	8	}
291
292		/*
293		* Read the superblock and group descriptors and overwrite them.
294		*/
295		errcode_t ext2fs_image_super_read(ext2_filsys fs, int fd,
296		int flags EXT2FS_ATTR((unused)))
297	0	{
298	0	char *buf;
299	0	ssize_t actual, size;
300	0	errcode_t retval;
301
302	0	size = (ssize_t)fs->blocksize * (fs->desc_blocks + 1);
303	0	buf = malloc(size);
304	0	if (!buf)
305	0	return ENOMEM;
306
307		/*
308		* Read it all in.
309		*/
310	0	actual = read(fd, buf, size);
311	0	if (actual == -1) {
312	0	retval = errno;
313	0	goto errout;
314	0	}
315	0	if (actual != size) {
316	0	retval = EXT2_ET_SHORT_READ;
317	0	goto errout;
318	0	}
319
320		/*
321		* Now copy in the superblock and group descriptors
322		*/
323	0	memcpy(fs->super, buf, SUPERBLOCK_SIZE);
324
325	0	memcpy(fs->group_desc, buf + fs->blocksize,
326	0	(ssize_t)fs->blocksize * fs->desc_blocks);
327
328	0	retval = 0;
329
330	0	errout:
331	0	free(buf);
332	0	return retval;
333	0	}
334
335		/*
336		* Write the block/inode bitmaps.
337		*/
338		errcode_t ext2fs_image_bitmap_write(ext2_filsys fs, int fd, int flags)
339	122	{
340	122	ext2fs_generic_bitmap bmap;
341	122	errcode_t retval;
342	122	ssize_t actual;
343	122	size_t c;
344	122	__u64 itr, cnt, size, total_size;
345	122	char buf[1024];
346
347	122	if (flags & IMAGER_FLAG_INODEMAP) {
348	0	if (!fs->inode_map) {
349	0	retval = ext2fs_read_inode_bitmap(fs);
350	0	if (retval)
351	0	return retval;
352	0	}
353	0	bmap = fs->inode_map;
354	0	itr = 1;
355	0	cnt = (__u64)EXT2_INODES_PER_GROUP(fs->super) *
356	0	fs->group_desc_count;
357	0	size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
358	122	} else {
359	122	if (!fs->block_map) {
360	122	retval = ext2fs_read_block_bitmap(fs);
361	122	if (retval)
362	24	return retval;
363	122	}
364	98	bmap = fs->block_map;
365	98	itr = fs->super->s_first_data_block;
366	98	cnt = EXT2_GROUPS_TO_CLUSTERS(fs->super, fs->group_desc_count);
367	98	size = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8;
368	98	}
369	98	total_size = size * fs->group_desc_count;
370
371	86.0k	while (cnt > 0) {
372	85.9k	size = sizeof(buf);
373	85.9k	if (size > (cnt >> 3))
374	86	size = (cnt >> 3);
375	85.9k	if (size == 0)
376	21	break;
377
378	85.9k	retval = ext2fs_get_generic_bmap_range(bmap, itr,
379	85.9k	size << 3, buf);
380	85.9k	if (retval)
381	0	return retval;
382
383	85.9k	actual = write(fd, buf, size);
384	85.9k	if (actual == -1)
385	0	return errno;
386	85.9k	if (actual != (int) size)
387	0	return EXT2_ET_SHORT_READ;
388
389	85.9k	itr += size << 3;
390	85.9k	cnt -= size << 3;
391	85.9k	}
392
393	98	size = total_size % fs->blocksize;
394	98	memset(buf, 0, sizeof(buf));
395	98	if (size) {
396	65	size = fs->blocksize - size;
397	254	while (size) {
398	189	c = size;
399	189	if (c > (int) sizeof(buf))
400	124	c = sizeof(buf);
401	189	actual = write(fd, buf, c);
402	189	if (actual < 0)
403	0	return errno;
404	189	if ((size_t) actual != c)
405	0	return EXT2_ET_SHORT_WRITE;
406	189	size -= c;
407	189	}
408	65	}
409	98	return 0;
410	98	}
411
412
413		/*
414		* Read the block/inode bitmaps.
415		*/
416		errcode_t ext2fs_image_bitmap_read(ext2_filsys fs, int fd, int flags)
417	88	{
418	88	ext2fs_generic_bitmap bmap;
419	88	errcode_t retval;
420	88	__u64 itr, cnt;
421	88	char buf[1024];
422	88	unsigned int size;
423	88	ssize_t actual;
424
425	88	if (flags & IMAGER_FLAG_INODEMAP) {
426	0	if (!fs->inode_map) {
427	0	retval = ext2fs_read_inode_bitmap(fs);
428	0	if (retval)
429	0	return retval;
430	0	}
431	0	bmap = fs->inode_map;
432	0	itr = 1;
433	0	cnt = (__u64)EXT2_INODES_PER_GROUP(fs->super) *
434	0	fs->group_desc_count;
435	0	size = (EXT2_INODES_PER_GROUP(fs->super) / 8);
436	88	} else {
437	88	if (!fs->block_map) {
438	88	retval = ext2fs_read_block_bitmap(fs);
439	88	if (retval)
440	9	return retval;
441	88	}
442	79	bmap = fs->block_map;
443	79	itr = fs->super->s_first_data_block;
444	79	cnt = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count);
445	79	size = EXT2_BLOCKS_PER_GROUP(fs->super) / 8;
446	79	}
447
448	79	while (cnt > 0) {
449	79	size = sizeof(buf);
450	79	if (size > (cnt >> 3))
451	53	size = (cnt >> 3);
452	79	if (size == 0)
453	0	break;
454
455	79	actual = read(fd, buf, size);
456	79	if (actual == -1)
457	0	return errno;
458	79	if (actual != (int) size)
459	79	return EXT2_ET_SHORT_READ;
460
461	0	retval = ext2fs_set_generic_bmap_range(bmap, itr,
462	0	size << 3, buf);
463	0	if (retval)
464	0	return retval;
465
466	0	itr += size << 3;
467	0	cnt -= size << 3;
468	0	}
469	0	return 0;
470	79	}