Add support for sparse ext4 image creation.
This adds the -s option to the make_ext4fs tool, which now creates
"sparse" filesystem images, which is very useful for the large 32 Gbyte
filesystems we are now building.
This check-in also fixes make_ext4fs to properly create filesystems
larger thatn 4 Gbytes on 64-bit Linux, 32-bit android and Macs.
Change-Id: Ie5838492fcf944f5c875481693c0dbd7013deae4
diff --git a/ext4_utils/Android.mk b/ext4_utils/Android.mk
index 3f8b10e..1470254 100644
--- a/ext4_utils/Android.mk
+++ b/ext4_utils/Android.mk
@@ -63,6 +63,13 @@
include $(CLEAR_VARS)
+LOCAL_SRC_FILES := simg2img.c
+LOCAL_MODULE := simg2img
+
+include $(BUILD_HOST_EXECUTABLE)
+
+include $(CLEAR_VARS)
+
LOCAL_MODULE := mkuserimg.sh
LOCAL_SRC_FILES := mkuserimg.sh
LOCAL_MODULE_CLASS := EXECUTABLES
diff --git a/ext4_utils/backed_block.c b/ext4_utils/backed_block.c
index 5fa6943..c1a2f20 100644
--- a/ext4_utils/backed_block.c
+++ b/ext4_utils/backed_block.c
@@ -113,9 +113,9 @@
last_block = db->block + DIV_ROUND_UP(db->len, info.block_size) - 1;
if (db->filename)
- file_func(out, db->block * info.block_size, db->filename, db->offset, db->len);
+ file_func(out, (u64)db->block * info.block_size, db->filename, db->offset, db->len);
else
- data_func(out, db->block * info.block_size, db->data, db->len);
+ data_func(out, (u64)db->block * info.block_size, db->data, db->len);
}
}
diff --git a/ext4_utils/ext4_utils.c b/ext4_utils/ext4_utils.c
index cd82827..f34985f 100644
--- a/ext4_utils/ext4_utils.c
+++ b/ext4_utils/ext4_utils.c
@@ -14,6 +14,19 @@
* limitations under the License.
*/
+#include <fcntl.h>
+#include <arpa/inet.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <string.h>
+
+#if defined(__linux__)
+#include <linux/fs.h>
+#elif defined(__APPLE__) && defined(__MACH__)
+#include <sys/disk.h>
+#endif
+
#include "ext4_utils.h"
#include "output_file.h"
#include "backed_block.h"
@@ -25,18 +38,6 @@
#include "ext4.h"
#include "jbd2.h"
-#include <fcntl.h>
-#include <arpa/inet.h>
-#include <sys/ioctl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#if defined(__linux__)
-#include <linux/fs.h>
-#elif defined(__APPLE__) && defined(__MACH__)
-#include <sys/disk.h>
-#endif
-
int force = 0;
struct fs_info info;
struct fs_aux_info aux_info;
@@ -73,24 +74,36 @@
}
/* Write the filesystem image to a file */
-void write_ext4_image(const char *filename, int gz)
+void write_ext4_image(const char *filename, int gz, int sparse)
{
int ret = 0;
- struct output_file *out = open_output_file(filename, gz);
+ struct output_file *out = open_output_file(filename, gz, sparse);
off_t off;
if (!out)
return;
- write_data_block(out, 1024, (u8*)aux_info.sb, 1024);
+ /* The write_data* functions expect only block aligned calls.
+ * This is not an issue, except when we write out the super
+ * block on a system with a block size > 1K. So, we need to
+ * deal with that here.
+ */
+ if (info.block_size > 1024) {
+ u8 buf[4096] = { 0 }; /* The larget supported ext4 block size */
+ memcpy(buf + 1024, (u8*)aux_info.sb, 1024);
+ write_data_block(out, 0, buf, info.block_size);
- write_data_block(out, (aux_info.first_data_block + 1) * info.block_size,
+ } else {
+ write_data_block(out, 1024, (u8*)aux_info.sb, 1024);
+ }
+
+ write_data_block(out, (u64)(aux_info.first_data_block + 1) * info.block_size,
(u8*)aux_info.bg_desc,
aux_info.bg_desc_blocks * info.block_size);
for_each_data_block(write_data_block, write_data_file, out);
- write_data_block(out, info.len - 1, (u8*)"", 1);
+ pad_output_file(out, info.len);
close_output_file(out);
}
diff --git a/ext4_utils/ext4_utils.h b/ext4_utils/ext4_utils.h
index 0a2b542..697c8d9 100644
--- a/ext4_utils/ext4_utils.h
+++ b/ext4_utils/ext4_utils.h
@@ -116,7 +116,7 @@
}
int ext4_bg_has_super_block(int bg);
-void write_ext4_image(const char *filename, int gz);
+void write_ext4_image(const char *filename, int gz, int sparse);
void ext4_create_fs_aux_info(void);
void ext4_free_fs_aux_info(void);
void ext4_fill_in_sb(void);
diff --git a/ext4_utils/make_ext4fs.c b/ext4_utils/make_ext4fs.c
index f77af0c..87588ab 100644
--- a/ext4_utils/make_ext4fs.c
+++ b/ext4_utils/make_ext4fs.c
@@ -62,6 +62,8 @@
root_inode = make_directory(0, 1, &dentries, 1);
inode = make_directory(root_inode, 0, NULL, 0);
*dentries.inode = inode;
+ inode_set_permissions(inode, dentries.mode,
+ dentries.uid, dentries.gid, dentries.mtime);
return root_inode;
}
@@ -225,7 +227,7 @@
}
int make_ext4fs(const char *filename, const char *directory,
- char *mountpoint, int android, int gzip)
+ char *mountpoint, int android, int gzip, int sparse)
{
u32 root_inode_num;
u16 root_mode;
@@ -319,7 +321,7 @@
aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
aux_info.sb->s_blocks_count_lo);
- write_ext4_image(filename, gzip);
+ write_ext4_image(filename, gzip, sparse);
return 0;
}
diff --git a/ext4_utils/make_ext4fs.h b/ext4_utils/make_ext4fs.h
index 4045e6a..8c6b259 100644
--- a/ext4_utils/make_ext4fs.h
+++ b/ext4_utils/make_ext4fs.h
@@ -22,6 +22,6 @@
void reset_ext4fs_info();
int make_ext4fs(const char *filename, const char *directory,
- char *mountpoint, int android, int gzip);
+ char *mountpoint, int android, int gzip, int sparse);
#endif
diff --git a/ext4_utils/make_ext4fs_main.c b/ext4_utils/make_ext4fs_main.c
index afea662..66d7aac 100644
--- a/ext4_utils/make_ext4fs_main.c
+++ b/ext4_utils/make_ext4fs_main.c
@@ -33,6 +33,7 @@
fprintf(stderr, "%s [ -l <len> ] [ -j <journal size> ] [ -b <block_size> ]\n", basename(path));
fprintf(stderr, " [ -g <blocks per group> ] [ -i <inodes> ] [ -I <inode size> ]\n");
fprintf(stderr, " [ -L <label> ] [ -f ] [ -a <android mountpoint> ]\n");
+ fprintf(stderr, " [ -z | -s ] [ -J ]\n");
fprintf(stderr, " <filename> [<directory>]\n");
}
@@ -44,8 +45,9 @@
char *mountpoint = "";
int android = 0;
int gzip = 0;
+ int sparse = 0;
- while ((opt = getopt(argc, argv, "l:j:b:g:i:I:L:a:fzJ")) != -1) {
+ while ((opt = getopt(argc, argv, "l:j:b:g:i:I:L:a:fzJs")) != -1) {
switch (opt) {
case 'l':
info.len = parse_num(optarg);
@@ -81,12 +83,21 @@
case 'J':
info.no_journal = 1;
break;
+ case 's':
+ sparse = 1;
+ break;
default: /* '?' */
usage(argv[0]);
exit(EXIT_FAILURE);
}
}
+ if (gzip && sparse) {
+ fprintf(stderr, "Cannot specify both gzip and sparse\n");
+ usage(argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
if (optind >= argc) {
fprintf(stderr, "Expected filename after options\n");
usage(argv[0]);
@@ -104,5 +115,5 @@
exit(EXIT_FAILURE);
}
- return make_ext4fs(filename, directory, mountpoint, android, gzip);
+ return make_ext4fs(filename, directory, mountpoint, android, gzip, sparse);
}
diff --git a/ext4_utils/output_file.c b/ext4_utils/output_file.c
index fa6af5f..2705701 100644
--- a/ext4_utils/output_file.c
+++ b/ext4_utils/output_file.c
@@ -26,9 +26,20 @@
#include "ext4_utils.h"
#include "output_file.h"
+#include "sparse_format.h"
+
+#if defined(__APPLE__) && defined(__MACH__)
+#define lseek64 lseek
+#define off64_t off_t
+#endif
+
+#define SPARSE_HEADER_MAJOR_VER 1
+#define SPARSE_HEADER_MINOR_VER 0
+#define SPARSE_HEADER_LEN (sizeof(sparse_header_t))
+#define CHUNK_HEADER_LEN (sizeof(chunk_header_t))
struct output_file_ops {
- int (*seek)(struct output_file *, off_t);
+ int (*seek)(struct output_file *, off64_t);
int (*write)(struct output_file *, u8 *, int);
void (*close)(struct output_file *);
};
@@ -36,16 +47,20 @@
struct output_file {
int fd;
gzFile gz_fd;
+ int sparse;
+ u64 cur_out_ptr;
+ int chunk_cnt;
+ u32 crc32;
struct output_file_ops *ops;
};
-static int file_seek(struct output_file *out, off_t off)
+static int file_seek(struct output_file *out, off64_t off)
{
- off_t ret;
+ off64_t ret;
- ret = lseek(out->fd, off, SEEK_SET);
+ ret = lseek64(out->fd, off, SEEK_SET);
if (ret < 0) {
- error_errno("lseek");
+ error_errno("lseek64");
return -1;
}
return 0;
@@ -78,9 +93,9 @@
.close = file_close,
};
-static int gz_file_seek(struct output_file *out, off_t off)
+static int gz_file_seek(struct output_file *out, off64_t off)
{
- off_t ret;
+ off64_t ret;
ret = gzseek(out->gz_fd, off, SEEK_SET);
if (ret < 0) {
@@ -116,18 +131,147 @@
.close = gz_file_close,
};
+static sparse_header_t sparse_header = {
+ .magic = SPARSE_HEADER_MAGIC,
+ .major_version = SPARSE_HEADER_MAJOR_VER,
+ .minor_version = SPARSE_HEADER_MINOR_VER,
+ .file_hdr_sz = SPARSE_HEADER_LEN,
+ .chunk_hdr_sz = CHUNK_HEADER_LEN,
+ .blk_sz = 0,
+ .total_blks = 0,
+ .total_chunks = 0,
+ .image_checksum = 0
+};
+
+static u8 *zero_buf;
+
+static int emit_skip_chunk(struct output_file *out, u64 skip_len)
+{
+ chunk_header_t chunk_header;
+ int ret;
+
+ //DBG printf("skip chunk: 0x%llx bytes\n", skip_len);
+
+ if (skip_len % info.block_size) {
+ error("don't care size %llu is not a multiple of the block size %u",
+ skip_len, info.block_size);
+ return -1;
+ }
+
+ /* We are skipping data, so emit a don't care chunk. */
+ chunk_header.chunk_type = CHUNK_TYPE_DONT_CARE;
+ chunk_header.reserved1 = 0;
+ chunk_header.chunk_sz = skip_len / info.block_size;
+ chunk_header.total_sz = CHUNK_HEADER_LEN;
+ ret = out->ops->write(out, (u8 *)&chunk_header, sizeof(chunk_header));
+ if (ret < 0)
+ return -1;
+ // KEN: TODO: CRC computation
+ out->cur_out_ptr += skip_len;
+ out->chunk_cnt++;
+
+ return 0;
+}
+
+static int write_chunk_raw(struct output_file *out, u64 off, u8 *data, int len)
+{
+ chunk_header_t chunk_header;
+ int rnd_up_len, zero_len;
+ int ret;
+
+ /* We can assume that all the chunks to be written are in
+ * ascending order, block-size aligned, and non-overlapping.
+ * So, if the offset is less than the current output pointer,
+ * throw an error, and if there is a gap, emit a "don't care"
+ * chunk. The first write (of the super block) may not be
+ * blocksize aligned, so we need to deal with that too.
+ */
+ //DBG printf("write chunk: offset 0x%llx, length 0x%x bytes\n", off, len);
+
+ if (off < out->cur_out_ptr) {
+ error("offset %llu is less than the current output offset %llu",
+ off, out->cur_out_ptr);
+ return -1;
+ }
+
+ if (off > out->cur_out_ptr) {
+ emit_skip_chunk(out, off - out->cur_out_ptr);
+ }
+
+ if (off % info.block_size) {
+ error("write chunk offset %llu is not a multiple of the block size %u",
+ off, info.block_size);
+ return -1;
+ }
+
+ if (off != out->cur_out_ptr) {
+ error("internal error, offset accounting screwy in write_chunk_raw()");
+ return -1;
+ }
+
+ /* Round up the file length to a multiple of the block size */
+ rnd_up_len = (len + (info.block_size - 1)) & (~(info.block_size -1));
+ zero_len = rnd_up_len - len;
+
+ /* Finally we can safely emit a chunk of data */
+ chunk_header.chunk_type = CHUNK_TYPE_RAW;
+ chunk_header.reserved1 = 0;
+ chunk_header.chunk_sz = rnd_up_len / info.block_size;
+ chunk_header.total_sz = CHUNK_HEADER_LEN + rnd_up_len;
+ ret = out->ops->write(out, (u8 *)&chunk_header, sizeof(chunk_header));
+
+ if (ret < 0)
+ return -1;
+ ret = out->ops->write(out, data, len);
+ if (ret < 0)
+ return -1;
+ if (zero_len) {
+ ret = out->ops->write(out, zero_buf, zero_len);
+ if (ret < 0)
+ return -1;
+ }
+
+ // KEN: TODO: CRC computation of both the raw data and and zero buf data written */
+ out->cur_out_ptr += rnd_up_len;
+ out->chunk_cnt++;
+
+ return 0;
+}
+
void close_output_file(struct output_file *out)
{
+ int ret;
+
+ if (out->sparse) {
+ /* we need to seek back to the beginning and update the file header */
+ sparse_header.total_chunks = out->chunk_cnt;
+ sparse_header.image_checksum = out->crc32;
+
+ ret = out->ops->seek(out, 0);
+ if (ret < 0)
+ error("failure seeking to start of sparse file");
+
+ ret = out->ops->write(out, (u8 *)&sparse_header, sizeof(sparse_header));
+ if (ret < 0)
+ error("failure updating sparse file header");
+ }
out->ops->close(out);
}
-struct output_file *open_output_file(const char *filename, int gz)
+struct output_file *open_output_file(const char *filename, int gz, int sparse)
{
+ int ret;
struct output_file *out = malloc(sizeof(struct output_file));
if (!out) {
- error_errno("malloc");
+ error_errno("malloc struct out");
return NULL;
}
+ zero_buf = malloc(info.block_size);
+ if (!zero_buf) {
+ error_errno("malloc zero_buf");
+ return NULL;
+ }
+ memset(zero_buf, '\0', info.block_size);
if (gz) {
out->ops = &gz_file_ops;
@@ -146,9 +290,61 @@
return NULL;
}
}
+ out->sparse = sparse;
+ out->cur_out_ptr = 0ll;
+ out->chunk_cnt = 0;
+ if (out->sparse) {
+ /* Write out the file header. We'll update the unknown fields
+ * when we close the file.
+ */
+ sparse_header.blk_sz = info.block_size,
+ sparse_header.total_blks = info.len / info.block_size,
+ ret = out->ops->write(out, (u8 *)&sparse_header, sizeof(sparse_header));
+ if (ret < 0)
+ return NULL;
+ }
+
return out;
}
+void pad_output_file(struct output_file *out, u64 len)
+{
+ int ret;
+
+ if (len > info.len) {
+ error("attempted to pad file %llu bytes past end of filesystem",
+ len - info.len);
+ return;
+ }
+ if (out->sparse) {
+ /* We need to emit a DONT_CARE chunk to pad out the file if the
+ * cur_out_ptr is not already at the end of the filesystem.
+ * We also need to compute the CRC for it.
+ */
+ //KEN: TODO: CRC computation!
+ if (len < out->cur_out_ptr) {
+ error("attempted to pad file %llu bytes less than the current output pointer",
+ out->cur_out_ptr - len);
+ return;
+ }
+ if (len > out->cur_out_ptr) {
+ emit_skip_chunk(out, len - out->cur_out_ptr);
+ }
+ } else {
+ //KEN TODO: Fixme. If the filesystem image needs no padding,
+ // this will overwrite the last byte in the file with 0
+ // The answer is to do accounting like the sparse image
+ // code does and know if there is already data there.
+ ret = out->ops->seek(out, len - 1);
+ if (ret < 0)
+ return;
+
+ ret = out->ops->write(out, (u8*)"", 1);
+ if (ret < 0)
+ return;
+ }
+}
+
/* Write a contiguous region of data blocks from a memory buffer */
void write_data_block(struct output_file *out, u64 off, u8 *data, int len)
{
@@ -160,13 +356,17 @@
return;
}
- ret = out->ops->seek(out, off);
- if (ret < 0)
- return;
+ if (out->sparse) {
+ write_chunk_raw(out, off, data, len);
+ } else {
+ ret = out->ops->seek(out, off);
+ if (ret < 0)
+ return;
- ret = out->ops->write(out, data, len);
- if (ret < 0)
- return;
+ ret = out->ops->write(out, data, len);
+ if (ret < 0)
+ return;
+ }
}
/* Write a contiguous region of data blocks from a file */
@@ -194,14 +394,17 @@
return;
}
- ret = out->ops->seek(out, off);
- if (ret < 0)
- goto err;
+ if (out->sparse) {
+ write_chunk_raw(out, off, data, len);
+ } else {
+ ret = out->ops->seek(out, off);
+ if (ret < 0)
+ goto err;
- ret = out->ops->write(out, data, len);
- if (ret < 0)
- goto err;
-
+ ret = out->ops->write(out, data, len);
+ if (ret < 0)
+ goto err;
+ }
munmap(data, len);
@@ -211,3 +414,4 @@
munmap(data, len);
close(file_fd);
}
+
diff --git a/ext4_utils/output_file.h b/ext4_utils/output_file.h
index 1df9e81..82b0952 100644
--- a/ext4_utils/output_file.h
+++ b/ext4_utils/output_file.h
@@ -16,8 +16,9 @@
struct output_file;
-struct output_file *open_output_file(const char *filename, int gz);
+struct output_file *open_output_file(const char *filename, int gz, int sparse);
void write_data_block(struct output_file *out, u64 off, u8 *data, int len);
void write_data_file(struct output_file *out, u64 off, const char *file,
off_t offset, int len);
+void pad_output_file(struct output_file *out, u64 len);
void close_output_file(struct output_file *out);
diff --git a/ext4_utils/simg2img.c b/ext4_utils/simg2img.c
new file mode 100644
index 0000000..9c1ad37
--- /dev/null
+++ b/ext4_utils/simg2img.c
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#define _LARGEFILE64_SOURCE
+#define _FILE_OFFSET_BITS 64
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+
+#include "ext4_utils.h"
+#include "output_file.h"
+#include "sparse_format.h"
+
+#if defined(__APPLE__) && defined(__MACH__)
+#define lseek64 lseek
+#define off64_t off_t
+#endif
+
+#define COPY_BUF_SIZE (1024*1024)
+u8 *copybuf;
+
+#define SPARSE_HEADER_MAJOR_VER 1
+#define SPARSE_HEADER_LEN (sizeof(sparse_header_t))
+#define CHUNK_HEADER_LEN (sizeof(chunk_header_t))
+
+void usage()
+{
+ fprintf(stderr, "Usage: simg2img <sparse_image_file> <raw_image_file>\n");
+}
+
+int process_raw_chunk(FILE *in, FILE *out, u32 blocks, u32 blk_sz, u32 *crc32)
+{
+ u64 len = (u64)blocks * blk_sz;
+ int chunk;
+
+ while (len) {
+ chunk = (len > COPY_BUF_SIZE) ? COPY_BUF_SIZE : len;
+ fread(copybuf, chunk, 1, in);
+ fwrite(copybuf, chunk, 1, out);
+ len -= chunk;
+ }
+
+ return blocks;
+}
+
+
+int process_skip_chunk(FILE *out, u32 blocks, u32 blk_sz, u32 *crc32)
+{
+ /* len needs to be 64 bits, as the sparse file specifies the skip amount
+ * as a 32 bit value of blocks.
+ */
+ u64 len = (u64)blocks * blk_sz;
+ long skip_chunk;
+
+ /* Fseek takes the offset as a long, which may be 32 bits on some systems.
+ * So, lets do a sequence of fseeks() with SEEK_CUR to get the file pointer
+ * where we want it.
+ */
+ while (len) {
+ skip_chunk = (len > 0x80000000) ? 0x80000000 : len;
+ fseek(out, skip_chunk, SEEK_CUR);
+ len -= skip_chunk;
+ }
+
+ return blocks;
+}
+
+int main(int argc, char *argv[])
+{
+ FILE *in, *out;
+ unsigned int i;
+ sparse_header_t sparse_header;
+ chunk_header_t chunk_header;
+ u32 crc32 = 0;
+ u32 total_blocks = 0;
+
+ if (argc != 3) {
+ usage();
+ exit(-1);
+ }
+
+ if ( (copybuf = malloc(COPY_BUF_SIZE)) == 0) {
+ fprintf(stderr, "Cannot malloc copy buf\n");
+ exit(-1);
+ }
+
+ if ((in = fopen(argv[1], "rb")) == 0) {
+ fprintf(stderr, "Cannot open input file %s\n", argv[1]);
+ exit(-1);
+ }
+
+ if ((out = fopen(argv[2], "wb")) == 0) {
+ fprintf(stderr, "Cannot open output file %s\n", argv[2]);
+ exit(-1);
+ }
+
+ if (fread(&sparse_header, sizeof(sparse_header), 1, in) != 1) {
+ fprintf(stderr, "Error reading sparse file header\n");
+ exit(-1);
+ }
+
+ if (sparse_header.magic != SPARSE_HEADER_MAGIC) {
+ fprintf(stderr, "Bad magic\n");
+ exit(-1);
+ }
+
+ if (sparse_header.major_version != SPARSE_HEADER_MAJOR_VER) {
+ fprintf(stderr, "Unknown major version number\n");
+ exit(-1);
+ }
+
+ if (sparse_header.file_hdr_sz > SPARSE_HEADER_LEN) {
+ /* Skip the remaining bytes in a header that is longer than
+ * we expected.
+ */
+ fseek(in, sparse_header.file_hdr_sz - SPARSE_HEADER_LEN, SEEK_CUR);
+ }
+
+ for (i=0; i<sparse_header.total_chunks; i++) {
+ if (fread(&chunk_header, sizeof(chunk_header), 1, in) != 1) {
+ fprintf(stderr, "Error reading chunk header\n");
+ exit(-1);
+ }
+
+ if (sparse_header.chunk_hdr_sz > CHUNK_HEADER_LEN) {
+ /* Skip the remaining bytes in a header that is longer than
+ * we expected.
+ */
+ fseek(in, sparse_header.chunk_hdr_sz - CHUNK_HEADER_LEN, SEEK_CUR);
+ }
+
+ switch (chunk_header.chunk_type) {
+ case CHUNK_TYPE_RAW:
+ if (chunk_header.total_sz != (sparse_header.chunk_hdr_sz +
+ (chunk_header.chunk_sz * sparse_header.blk_sz)) ) {
+ fprintf(stderr, "Bogus chunk size for chunk %d, type Raw\n", i);
+ exit(-1);
+ }
+ total_blocks += process_raw_chunk(in, out,
+ chunk_header.chunk_sz, sparse_header.blk_sz, &crc32);
+ break;
+ case CHUNK_TYPE_DONT_CARE:
+ if (chunk_header.total_sz != sparse_header.chunk_hdr_sz) {
+ fprintf(stderr, "Bogus chunk size for chunk %d, type Dont Care\n", i);
+ exit(-1);
+ }
+ total_blocks += process_skip_chunk(out,
+ chunk_header.chunk_sz, sparse_header.blk_sz, &crc32);
+ break;
+ default:
+ fprintf(stderr, "Unknown chunk type 0x%4.4x\n", chunk_header.chunk_type);
+ exit(-1);
+ }
+
+ }
+
+ /* If the last chunk was a skip, then the code just did a seek, but
+ * no write, and the file won't actually be the correct size. This
+ * will make the file the correct size. Make sure the offset is
+ * computed in 64 bits, and the function called can handle 64 bits.
+ */
+ ftruncate(fileno(out), (u64)total_blocks * sparse_header.blk_sz);
+
+ fclose(in);
+ fclose(out);
+
+ if (sparse_header.total_blks != total_blocks) {
+ fprintf(stderr, "Wrote %d blocks, expected to write %d blocks\n",
+ total_blocks, sparse_header.total_blks);
+ exit(-1);
+ }
+
+ if (sparse_header.image_checksum != crc32) {
+ fprintf(stderr, "computed crc32 of %d, expected %d\n",
+ crc32, sparse_header.image_checksum);
+ exit(-1);
+ }
+
+ exit(0);
+}
+
diff --git a/ext4_utils/sparse_format.h b/ext4_utils/sparse_format.h
new file mode 100644
index 0000000..ba13214
--- /dev/null
+++ b/ext4_utils/sparse_format.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+typedef struct sparse_header {
+ __le32 magic; /* 0xed26ff3a */
+ __le16 major_version; /* (0x1) - reject images with higher major versions */
+ __le16 minor_version; /* (0x0) - allow images with higer minor versions */
+ __le16 file_hdr_sz; /* 28 bytes for first revision of the file format */
+ __le16 chunk_hdr_sz; /* 12 bytes for first revision of the file format */
+ __le32 blk_sz; /* block size in bytes, must be a multiple of 4 (4096) */
+ __le32 total_blks; /* total blocks in the non-sparse output image */
+ __le32 total_chunks; /* total chunks in the sparse input image */
+ __le32 image_checksum; /* CRC32 checksum of the original data, counting "don't care" */
+ /* as 0. Standard 802.3 polynomial, use a Public Domain */
+ /* table implementation */
+} sparse_header_t;
+
+#define SPARSE_HEADER_MAGIC 0xed26ff3a
+
+#define CHUNK_TYPE_RAW 0xCAC1
+#define CHUNK_TYPE_FILL 0xCAC2
+#define CHUNK_TYPE_DONT_CARE 0xCAC3
+
+typedef struct chunk_header {
+ __le16 chunk_type; /* 0xCAC1 -> raw; 0xCAC2 -> fill; 0xCAC3 -> don't care */
+ __le16 reserved1;
+ __le32 chunk_sz; /* in blocks in output image */
+ __le32 total_sz; /* in bytes of chunk input file including chunk header and data */
+} chunk_header_t;
+
+/* Following a Raw or Fill chunk is data. For a Raw chunk, it's the data in chunk_sz * blk_sz.
+ * For a Fill chunk, it's 4 bytes of the fill data.
+ */
+