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Diffstat (limited to 'lib/sqfs/block_processor/block.c')
-rw-r--r--lib/sqfs/block_processor/block.c203
1 files changed, 203 insertions, 0 deletions
diff --git a/lib/sqfs/block_processor/block.c b/lib/sqfs/block_processor/block.c
new file mode 100644
index 0000000..49892be
--- /dev/null
+++ b/lib/sqfs/block_processor/block.c
@@ -0,0 +1,203 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * process_block.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+#include <string.h>
+
+static int store_block_location(sqfs_block_processor_t *proc, sqfs_u64 offset,
+ sqfs_u32 size, sqfs_u32 chksum)
+{
+ size_t new_sz;
+ void *new;
+
+ if (proc->num_blocks == proc->max_blocks) {
+ new_sz = proc->max_blocks * 2;
+ new = realloc(proc->blocks, sizeof(proc->blocks[0]) * new_sz);
+
+ if (new == NULL)
+ return SQFS_ERROR_ALLOC;
+
+ proc->blocks = new;
+ proc->max_blocks = new_sz;
+ }
+
+ proc->blocks[proc->num_blocks].offset = offset;
+ proc->blocks[proc->num_blocks].hash = MK_BLK_HASH(chksum, size);
+ proc->num_blocks += 1;
+ return 0;
+}
+
+static size_t deduplicate_blocks(sqfs_block_processor_t *proc, size_t count)
+{
+ size_t i, j;
+
+ for (i = 0; i < proc->file_start; ++i) {
+ for (j = 0; j < count; ++j) {
+ if (proc->blocks[i + j].hash !=
+ proc->blocks[proc->file_start + j].hash)
+ break;
+ }
+
+ if (j == count)
+ break;
+ }
+
+ return i;
+}
+
+static int align_file(sqfs_block_processor_t *proc, sqfs_block_t *blk)
+{
+ sqfs_u32 chksum;
+ void *padding;
+ sqfs_u64 size;
+ size_t diff;
+ int ret;
+
+ if (!(blk->flags & SQFS_BLK_ALIGN))
+ return 0;
+
+ size = proc->file->get_size(proc->file);
+ diff = size % proc->devblksz;
+ if (diff == 0)
+ return 0;
+
+ padding = calloc(1, diff);
+ if (padding == 0)
+ return SQFS_ERROR_ALLOC;
+
+ if (proc->hooks != NULL && proc->hooks->prepare_padding != NULL)
+ proc->hooks->prepare_padding(proc->user_ptr, padding, diff);
+
+ chksum = crc32(0, padding, diff);
+
+ ret = proc->file->write_at(proc->file, size, padding, diff);
+ free(padding);
+ if (ret)
+ return ret;
+
+ return store_block_location(proc, size, diff | (1 << 24), chksum);
+}
+
+int process_completed_block(sqfs_block_processor_t *proc, sqfs_block_t *blk)
+{
+ sqfs_u64 offset, bytes;
+ size_t start, count;
+ sqfs_u32 out;
+ int err;
+
+ if (proc->hooks != NULL && proc->hooks->pre_block_write != NULL) {
+ proc->hooks->pre_block_write(proc->user_ptr, blk, proc->file);
+ }
+
+ if (blk->flags & SQFS_BLK_FIRST_BLOCK) {
+ proc->start = proc->file->get_size(proc->file);
+ proc->file_start = proc->num_blocks;
+
+ err = align_file(proc, blk);
+ if (err)
+ return err;
+ }
+
+ if (blk->size != 0) {
+ out = blk->size;
+ if (!(blk->flags & SQFS_BLK_IS_COMPRESSED))
+ out |= 1 << 24;
+
+ offset = proc->file->get_size(proc->file);
+
+ if (blk->flags & SQFS_BLK_FRAGMENT_BLOCK) {
+ err = sqfs_frag_table_set(proc->frag_tbl, blk->index,
+ offset, out);
+ if (err)
+ return err;
+ } else {
+ blk->inode->extra[blk->index] = out;
+ }
+
+ err = store_block_location(proc, offset, out, blk->checksum);
+ if (err)
+ return err;
+
+ err = proc->file->write_at(proc->file, offset,
+ blk->data, blk->size);
+ if (err)
+ return err;
+ }
+
+ if (proc->hooks != NULL && proc->hooks->post_block_write != NULL) {
+ proc->hooks->post_block_write(proc->user_ptr, blk, proc->file);
+ }
+
+ if (blk->flags & SQFS_BLK_LAST_BLOCK) {
+ err = align_file(proc, blk);
+ if (err)
+ return err;
+
+ count = proc->num_blocks - proc->file_start;
+ start = deduplicate_blocks(proc, count);
+ offset = proc->blocks[start].offset;
+
+ sqfs_inode_set_file_block_start(blk->inode, offset);
+
+ if (start >= proc->file_start)
+ return 0;
+
+ offset = start + count;
+ if (offset >= proc->file_start) {
+ count = proc->num_blocks - offset;
+ proc->num_blocks = offset;
+ } else {
+ proc->num_blocks = proc->file_start;
+ }
+
+ if (proc->hooks != NULL &&
+ proc->hooks->notify_blocks_erased != NULL) {
+ bytes = proc->file->get_size(proc->file) - proc->start;
+
+ proc->hooks->notify_blocks_erased(proc->user_ptr,
+ count, bytes);
+ }
+
+ err = proc->file->truncate(proc->file, proc->start);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+int block_processor_do_block(sqfs_block_t *block, sqfs_compressor_t *cmp,
+ sqfs_u8 *scratch, size_t scratch_size)
+{
+ ssize_t ret;
+
+ if (block->size == 0) {
+ block->checksum = 0;
+ return 0;
+ }
+
+ block->checksum = crc32(0, block->data, block->size);
+
+ if (block->flags & SQFS_BLK_IS_FRAGMENT)
+ return 0;
+
+ if (!(block->flags & SQFS_BLK_DONT_COMPRESS)) {
+ ret = cmp->do_block(cmp, block->data, block->size,
+ scratch, scratch_size);
+ if (ret < 0)
+ return ret;
+
+ if (ret > 0) {
+ memcpy(block->data, scratch, ret);
+ block->size = ret;
+ block->flags |= SQFS_BLK_IS_COMPRESSED;
+ }
+ }
+
+ return 0;
+}