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-rw-r--r--lib/sqfshelper/data_writer.c528
1 files changed, 528 insertions, 0 deletions
diff --git a/lib/sqfshelper/data_writer.c b/lib/sqfshelper/data_writer.c
new file mode 100644
index 0000000..d4b402b
--- /dev/null
+++ b/lib/sqfshelper/data_writer.c
@@ -0,0 +1,528 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * data_writer.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "block_processor.h"
+#include "data_writer.h"
+#include "highlevel.h"
+#include "util.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <zlib.h>
+
+struct data_writer_t {
+ block_t *frag_block;
+ sqfs_fragment_t *fragments;
+ size_t num_fragments;
+ size_t max_fragments;
+
+ size_t devblksz;
+ uint64_t bytes_written;
+ off_t start;
+
+ block_processor_t *proc;
+ compressor_t *cmp;
+ file_info_t *list;
+ sqfs_super_t *super;
+ int outfd;
+};
+
+enum {
+ BLK_FIRST_BLOCK = BLK_USER,
+ BLK_LAST_BLOCK = BLK_USER << 1,
+ BLK_ALLIGN = BLK_USER << 2,
+ BLK_FRAGMENT_BLOCK = BLK_USER << 3,
+};
+
+static int save_position(data_writer_t *data)
+{
+ data->bytes_written = data->super->bytes_used;
+ data->start = lseek(data->outfd, 0, SEEK_CUR);
+
+ if (data->start == (off_t)-1) {
+ perror("querying current position on squashfs image");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int restore_position(data_writer_t *data)
+{
+ if (lseek(data->outfd, data->start, SEEK_SET) == (off_t)-1)
+ goto fail_seek;
+
+ if (ftruncate(data->outfd, data->start))
+ goto fail_truncate;
+
+ data->super->bytes_used = data->bytes_written;
+ return 0;
+fail_seek:
+ perror("seeking on squashfs image after file deduplication");
+ return -1;
+fail_truncate:
+ perror("truncating squashfs image after file deduplication");
+ return -1;
+}
+
+static int allign_file(data_writer_t *data)
+{
+ size_t diff = data->super->bytes_used % data->devblksz;
+
+ if (diff == 0)
+ return 0;
+
+ if (padd_file(data->outfd, data->super->bytes_used, data->devblksz))
+ return -1;
+
+ data->super->bytes_used += data->devblksz - diff;
+ return 0;
+}
+
+static int block_callback(void *user, block_t *blk)
+{
+ file_info_t *fi = blk->user;
+ data_writer_t *data = user;
+ uint64_t ref, offset;
+ uint32_t out;
+
+ if (blk->flags & BLK_FIRST_BLOCK) {
+ if (save_position(data))
+ return -1;
+
+ if ((blk->flags & BLK_ALLIGN) && allign_file(data) != 0)
+ return -1;
+
+ fi->startblock = data->super->bytes_used;
+ }
+
+ if (blk->size == 0)
+ goto skip_sentinel;
+
+ out = blk->size;
+ if (!(blk->flags & BLK_IS_COMPRESSED))
+ out |= 1 << 24;
+
+ if (blk->flags & BLK_FRAGMENT_BLOCK) {
+ offset = htole64(data->super->bytes_used);
+ data->fragments[blk->index].start_offset = offset;
+ data->fragments[blk->index].pad0 = 0;
+ data->fragments[blk->index].size = htole32(out);
+
+ data->super->flags &= ~SQFS_FLAG_NO_FRAGMENTS;
+ data->super->flags |= SQFS_FLAG_ALWAYS_FRAGMENTS;
+ } else {
+ fi->blocks[blk->index].chksum = blk->checksum;
+ fi->blocks[blk->index].size = htole32(out);
+ }
+
+ if (write_data("writing data block", data->outfd,
+ blk->data, blk->size)) {
+ return -1;
+ }
+
+ data->super->bytes_used += blk->size;
+
+skip_sentinel:
+ if (blk->flags & BLK_LAST_BLOCK) {
+ if ((blk->flags & BLK_ALLIGN) && allign_file(data) != 0)
+ return -1;
+
+ ref = find_equal_blocks(fi, data->list,
+ data->super->block_size);
+ if (ref > 0) {
+ fi->startblock = ref;
+ fi->flags |= FILE_FLAG_BLOCKS_ARE_DUPLICATE;
+
+ if (restore_position(data))
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+/*****************************************************************************/
+
+static int flush_fragment_block(data_writer_t *data)
+{
+ size_t newsz;
+ void *new;
+ int ret;
+
+ if (data->num_fragments == data->max_fragments) {
+ newsz = data->max_fragments ? data->max_fragments * 2 : 16;
+ new = realloc(data->fragments,
+ sizeof(data->fragments[0]) * newsz);
+
+ if (new == NULL) {
+ perror("appending to fragment table");
+ return -1;
+ }
+
+ data->max_fragments = newsz;
+ data->fragments = new;
+ }
+
+ data->frag_block->index = data->num_fragments++;
+
+ ret = block_processor_enqueue(data->proc, data->frag_block);
+ data->frag_block = NULL;
+ return ret;
+}
+
+static int store_fragment(data_writer_t *data, block_t *frag)
+{
+ file_info_t *fi = frag->user;
+ size_t size;
+
+ if (data->frag_block != NULL) {
+ size = data->frag_block->size + frag->size;
+
+ if (size > data->super->block_size) {
+ if (flush_fragment_block(data))
+ goto fail;
+ }
+ }
+
+ if (data->frag_block == NULL) {
+ size = sizeof(block_t) + data->super->block_size;
+
+ data->frag_block = calloc(1, size);
+ if (data->frag_block == NULL) {
+ perror("creating fragment block");
+ goto fail;
+ }
+
+ data->frag_block->flags = BLK_DONT_CHECKSUM;
+ data->frag_block->flags |= BLK_FRAGMENT_BLOCK;
+ }
+
+ fi->fragment_offset = data->frag_block->size;
+ fi->fragment = data->num_fragments;
+
+ data->frag_block->flags |= (frag->flags & BLK_DONT_COMPRESS);
+ memcpy(data->frag_block->data + data->frag_block->size,
+ frag->data, frag->size);
+
+ data->frag_block->size += frag->size;
+ free(frag);
+ return 0;
+fail:
+ free(frag);
+ return -1;
+}
+
+static bool is_zero_block(unsigned char *ptr, size_t size)
+{
+ return ptr[0] == 0 && memcmp(ptr, ptr + 1, size - 1) == 0;
+}
+
+static int handle_fragment(data_writer_t *data, block_t *blk)
+{
+ file_info_t *fi = blk->user, *ref;
+
+ fi->fragment_chksum = crc32(0, blk->data, blk->size);
+
+ ref = fragment_by_chksum(fi, fi->fragment_chksum, blk->size,
+ data->list, data->super->block_size);
+
+ if (ref != NULL) {
+ fi->fragment_offset = ref->fragment_offset;
+ fi->fragment = ref->fragment;
+ fi->flags |= FILE_FLAG_FRAGMENT_IS_DUPLICATE;
+ free(blk);
+ return 0;
+ }
+
+ return store_fragment(data, blk);
+}
+
+static int add_sentinel_block(data_writer_t *data, file_info_t *fi,
+ uint32_t flags)
+{
+ block_t *blk = calloc(1, sizeof(*blk));
+
+ if (blk == NULL) {
+ perror("creating sentinel block");
+ return -1;
+ }
+
+ blk->user = fi;
+ blk->flags = BLK_DONT_COMPRESS | BLK_DONT_CHECKSUM | flags;
+
+ return block_processor_enqueue(data->proc, blk);
+}
+
+int write_data_from_fd(data_writer_t *data, file_info_t *fi,
+ int infd, int flags)
+{
+ uint32_t blk_flags = BLK_FIRST_BLOCK;
+ uint64_t file_size = fi->size;
+ size_t diff, i = 0;
+ block_t *blk;
+
+ if (flags & DW_DONT_COMPRESS)
+ blk_flags |= BLK_DONT_COMPRESS;
+
+ if (flags & DW_ALLIGN_DEVBLK)
+ blk_flags |= BLK_ALLIGN;
+
+ fi->next = data->list;
+ data->list = fi;
+
+ for (; file_size > 0; file_size -= diff) {
+ if (file_size > data->super->block_size) {
+ diff = data->super->block_size;
+ } else {
+ diff = file_size;
+ }
+
+ blk = create_block(fi->input_file, infd, diff, fi, blk_flags);
+ if (blk == NULL)
+ return -1;
+
+ blk->index = i++;
+
+ if (is_zero_block(blk->data, blk->size)) {
+ fi->blocks[blk->index].chksum = 0;
+ fi->blocks[blk->index].size = 0;
+ free(blk);
+ continue;
+ }
+
+ if (diff < data->super->block_size &&
+ !(flags & DW_DONT_FRAGMENT)) {
+ fi->flags |= FILE_FLAG_HAS_FRAGMENT;
+
+ if (!(blk_flags & (BLK_FIRST_BLOCK | BLK_LAST_BLOCK))) {
+ blk_flags |= BLK_LAST_BLOCK;
+
+ if (add_sentinel_block(data, fi, blk_flags)) {
+ free(blk);
+ return -1;
+ }
+ }
+
+ if (handle_fragment(data, blk))
+ return -1;
+ } else {
+ if (block_processor_enqueue(data->proc, blk))
+ return -1;
+
+ blk_flags &= ~BLK_FIRST_BLOCK;
+ }
+ }
+
+ if (!(blk_flags & (BLK_FIRST_BLOCK | BLK_LAST_BLOCK))) {
+ blk_flags |= BLK_LAST_BLOCK;
+
+ if (add_sentinel_block(data, fi, blk_flags))
+ return -1;
+ }
+
+ return 0;
+}
+
+static int check_map_valid(const sparse_map_t *map, file_info_t *fi)
+{
+ const sparse_map_t *m;
+ uint64_t offset;
+
+ if (map != NULL) {
+ offset = map->offset;
+
+ for (m = map; m != NULL; m = m->next) {
+ if (m->offset < offset)
+ goto fail_map;
+ offset = m->offset + m->count;
+ }
+
+ if (offset > fi->size)
+ goto fail_map_size;
+ }
+
+ return 0;
+fail_map_size:
+ fprintf(stderr, "%s: sparse file map spans beyond file size\n",
+ fi->input_file);
+ return -1;
+fail_map:
+ fprintf(stderr,
+ "%s: sparse file map is unordered or self overlapping\n",
+ fi->input_file);
+ return -1;
+}
+
+static int get_sparse_block(block_t *blk, file_info_t *fi, int infd,
+ sparse_map_t **sparse_map, uint64_t offset,
+ size_t diff)
+{
+ sparse_map_t *map = *sparse_map;
+ size_t start, count;
+
+ while (map != NULL && map->offset < offset + diff) {
+ start = 0;
+ count = map->count;
+
+ if (map->offset < offset)
+ count -= offset - map->offset;
+
+ if (map->offset > offset)
+ start = map->offset - offset;
+
+ if (start + count > diff)
+ count = diff - start;
+
+ if (read_data(fi->input_file, infd, blk->data + start, count))
+ return -1;
+
+ map = map->next;
+ }
+
+ *sparse_map = map;
+ return 0;
+}
+
+int write_data_from_fd_condensed(data_writer_t *data, file_info_t *fi,
+ int infd, sparse_map_t *map, int flags)
+{
+ uint32_t blk_flags = BLK_FIRST_BLOCK;
+ size_t diff, i = 0;
+ uint64_t offset;
+ block_t *blk;
+
+ if (check_map_valid(map, fi))
+ return -1;
+
+ if (flags & DW_DONT_COMPRESS)
+ blk_flags |= BLK_DONT_COMPRESS;
+
+ if (flags & DW_ALLIGN_DEVBLK)
+ blk_flags |= BLK_ALLIGN;
+
+ for (offset = 0; offset < fi->size; offset += diff) {
+ if (fi->size - offset > (uint64_t)data->super->block_size) {
+ diff = data->super->block_size;
+ } else {
+ diff = fi->size - offset;
+ }
+
+ blk = alloc_flex(sizeof(*blk), 1, diff);
+ blk->size = diff;
+ blk->index = i++;
+ blk->user = fi;
+ blk->flags = blk_flags;
+
+ if (get_sparse_block(blk, fi, infd, &map, offset, diff)) {
+ free(blk);
+ return -1;
+ }
+
+ if (is_zero_block(blk->data, blk->size)) {
+ fi->blocks[blk->index].chksum = 0;
+ fi->blocks[blk->index].size = 0;
+ free(blk);
+ continue;
+ }
+
+ if (diff < data->super->block_size &&
+ !(flags & DW_DONT_FRAGMENT)) {
+ fi->flags |= FILE_FLAG_HAS_FRAGMENT;
+
+ if (!(blk_flags & (BLK_FIRST_BLOCK | BLK_LAST_BLOCK))) {
+ blk_flags |= BLK_LAST_BLOCK;
+
+ if (add_sentinel_block(data, fi, blk_flags)) {
+ free(blk);
+ return -1;
+ }
+ }
+
+ if (handle_fragment(data, blk))
+ return -1;
+ } else {
+ if (block_processor_enqueue(data->proc, blk))
+ return -1;
+
+ blk_flags &= ~BLK_FIRST_BLOCK;
+ }
+ }
+
+ if (!(blk_flags & (BLK_FIRST_BLOCK | BLK_LAST_BLOCK))) {
+ blk_flags |= BLK_LAST_BLOCK;
+
+ if (add_sentinel_block(data, fi, blk_flags))
+ return -1;
+ }
+
+ return 0;
+}
+
+data_writer_t *data_writer_create(sqfs_super_t *super, compressor_t *cmp,
+ int outfd, size_t devblksize,
+ unsigned int num_jobs)
+{
+ data_writer_t *data = calloc(1, sizeof(*data));
+
+ if (data == NULL) {
+ perror("creating data writer");
+ return NULL;
+ }
+
+ data->proc = block_processor_create(super->block_size, cmp, num_jobs,
+ data, block_callback);
+ data->cmp = cmp;
+ data->super = super;
+ data->outfd = outfd;
+ data->devblksz = devblksize;
+ return data;
+}
+
+void data_writer_destroy(data_writer_t *data)
+{
+ block_processor_destroy(data->proc);
+ free(data->fragments);
+ free(data);
+}
+
+int data_writer_write_fragment_table(data_writer_t *data)
+{
+ uint64_t start;
+ size_t size;
+ int ret;
+
+ if (data->num_fragments == 0) {
+ data->super->fragment_entry_count = 0;
+ data->super->fragment_table_start = 0xFFFFFFFFFFFFFFFFUL;
+ return 0;
+ }
+
+ size = sizeof(data->fragments[0]) * data->num_fragments;
+ ret = sqfs_write_table(data->outfd, data->super, data->cmp,
+ data->fragments, size, &start);
+ if (ret)
+ return -1;
+
+ data->super->fragment_entry_count = data->num_fragments;
+ data->super->fragment_table_start = start;
+ return 0;
+}
+
+int data_writer_sync(data_writer_t *data)
+{
+ if (data->frag_block != NULL) {
+ if (flush_fragment_block(data))
+ return -1;
+ }
+
+ return block_processor_finish(data->proc);
+}