summaryrefslogtreecommitdiff
path: root/lib/sqfshelper/data_reader.c
diff options
context:
space:
mode:
authorDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-09-20 16:31:31 +0200
committerDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-09-20 18:34:17 +0200
commitd57efdfa0b7420dabf97335ffe3a8b391b9f54b3 (patch)
treef42eed71fc5c4a07ef03696c9953da7d4e860095 /lib/sqfshelper/data_reader.c
parentc106a290ed07fa89b39072925b1a2258071511a8 (diff)
Remove sqfs reader & fstree usage from sqfsdiff
Replace with direct usage of the dir reader and lower level data structures. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'lib/sqfshelper/data_reader.c')
-rw-r--r--lib/sqfshelper/data_reader.c155
1 files changed, 52 insertions, 103 deletions
diff --git a/lib/sqfshelper/data_reader.c b/lib/sqfshelper/data_reader.c
index 0c982d7..0780da0 100644
--- a/lib/sqfshelper/data_reader.c
+++ b/lib/sqfshelper/data_reader.c
@@ -247,113 +247,64 @@ fail_sparse:
return -1;
}
-int data_reader_dump_file(data_reader_t *data, file_info_t *fi, int outfd,
- bool allow_sparse)
-{
- uint64_t filesz = fi->size;
- size_t fragsz = fi->size % data->block_size;
- size_t count = fi->size / data->block_size;
- off_t off = fi->startblock;
- size_t i, diff;
-
- if (fragsz != 0 && (fi->fragment_offset >= data->block_size ||
- fi->fragment == 0xFFFFFFFF)) {
- fragsz = 0;
- ++count;
- }
-
- if (allow_sparse && ftruncate(outfd, filesz))
- goto fail_sparse;
-
- for (i = 0; i < count; ++i) {
- diff = filesz > data->block_size ? data->block_size : filesz;
- filesz -= diff;
-
- if (SQFS_IS_SPARSE_BLOCK(fi->block_size[i])) {
- if (allow_sparse) {
- if (lseek(outfd, diff, SEEK_CUR) == (off_t)-1)
- goto fail_sparse;
- continue;
- }
- memset(data->block, 0, diff);
- } else {
- if (precache_data_block(data, off, fi->block_size[i]))
- return -1;
- off += SQFS_ON_DISK_BLOCK_SIZE(fi->block_size[i]);
- }
-
- if (write_data("writing uncompressed block",
- outfd, data->block, diff)) {
- return -1;
- }
- }
-
- if (fragsz > 0) {
- if (precache_fragment_block(data, fi->fragment))
- return -1;
-
- if (fi->fragment_offset >= data->frag_used)
- goto fail_range;
-
- if ((fi->fragment_offset + fragsz - 1) >= data->frag_used)
- goto fail_range;
-
- if (write_data("writing uncompressed fragment", outfd,
- (char *)data->frag_block + fi->fragment_offset,
- fragsz)) {
- return -1;
- }
- }
-
- return 0;
-fail_range:
- fputs("attempted to read past fragment block limits\n", stderr);
- return -1;
-fail_sparse:
- perror("creating sparse output file");
- return -1;
-}
-
-ssize_t data_reader_read(data_reader_t *data, file_info_t *fi,
+ssize_t data_reader_read(data_reader_t *data,
+ const sqfs_inode_generic_t *inode,
uint64_t offset, void *buffer, size_t size)
{
- size_t i, diff, fragsz, count, total = 0;
- off_t off;
+ uint32_t frag_idx, frag_off;
+ size_t i, diff, total = 0;
+ uint64_t off, filesz;
char *ptr;
- /* work out block count and fragment size */
- fragsz = fi->size % data->block_size;
- count = fi->size / data->block_size;
-
- if (fragsz != 0 && (fi->fragment_offset >= data->block_size ||
- fi->fragment == 0xFFFFFFFF)) {
- fragsz = 0;
- ++count;
+ /* work out file location and size */
+ if (inode->base.type == SQFS_INODE_EXT_FILE) {
+ off = inode->data.file_ext.blocks_start;
+ filesz = inode->data.file_ext.file_size;
+ frag_idx = inode->data.file_ext.fragment_idx;
+ frag_off = inode->data.file_ext.fragment_offset;
+ } else {
+ off = inode->data.file.blocks_start;
+ filesz = inode->data.file.file_size;
+ frag_idx = inode->data.file.fragment_index;
+ frag_off = inode->data.file.fragment_offset;
}
- /* work out block index and on-disk location */
- off = fi->startblock;
+ /* find location of the first block */
i = 0;
- while (offset > data->block_size && i < count) {
- off += SQFS_ON_DISK_BLOCK_SIZE(fi->block_size[i++]);
+ while (offset > data->block_size && i < inode->num_file_blocks) {
+ off += SQFS_ON_DISK_BLOCK_SIZE(inode->block_sizes[i++]);
offset -= data->block_size;
+
+ if (filesz >= data->block_size) {
+ filesz -= data->block_size;
+ } else {
+ filesz = 0;
+ }
}
/* copy data from blocks */
- while (i < count && size > 0) {
+ while (i < inode->num_file_blocks && size > 0 && filesz > 0) {
diff = data->block_size - offset;
if (size < diff)
- size = diff;
+ diff = size;
- if (SQFS_IS_SPARSE_BLOCK(fi->block_size[i])) {
+ if (SQFS_IS_SPARSE_BLOCK(inode->block_sizes[i])) {
memset(buffer, 0, diff);
} else {
- if (precache_data_block(data, off, fi->block_size[i]))
+ if (precache_data_block(data, off,
+ inode->block_sizes[i])) {
return -1;
+ }
memcpy(buffer, (char *)data->block + offset, diff);
- off += SQFS_ON_DISK_BLOCK_SIZE(fi->block_size[i]);
+ off += SQFS_ON_DISK_BLOCK_SIZE(inode->block_sizes[i]);
+ }
+
+ if (filesz >= data->block_size) {
+ filesz -= data->block_size;
+ } else {
+ filesz = 0;
}
++i;
@@ -364,32 +315,30 @@ ssize_t data_reader_read(data_reader_t *data, file_info_t *fi,
}
/* copy from fragment */
- if (i == count && size > 0 && fragsz > 0) {
- if (precache_fragment_block(data, fi->fragment))
+ if (i == inode->num_file_blocks && size > 0 && filesz > 0) {
+ if (precache_fragment_block(data, frag_idx))
return -1;
- if (fi->fragment_offset >= data->frag_used)
+ if (frag_off >= data->frag_used)
goto fail_range;
- if ((fi->fragment_offset + fragsz - 1) >= data->frag_used)
+ if (frag_off + filesz > data->frag_used)
goto fail_range;
- ptr = (char *)data->frag_block + fi->fragment_offset;
- ptr += offset;
+ if (offset >= filesz)
+ return total;
- if (offset >= fragsz) {
- offset = 0;
- size = 0;
- }
+ if (offset + size > filesz)
+ size = filesz - offset;
- if (offset + size > fragsz)
- size = fragsz - offset;
+ if (size == 0)
+ return total;
- if (size > 0) {
- memcpy(buffer, ptr + offset, size);
- total += size;
- }
+ ptr = (char *)data->frag_block + frag_off + offset;
+ memcpy(buffer, ptr, size);
+ total += size;
}
+
return total;
fail_range:
fputs("attempted to read past fragment block limits\n", stderr);