From 577aae140e05f2b7cd140926443517260c0132b7 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Fri, 29 May 2020 19:27:28 +0200 Subject: Block processor: add flags to manage hashing & sparse block detection This commit adds 2 new user settable flags to the block processor: - A flag to ignore sparse blocks and treat them like normal data blocks. - A flag to disable checksum computation altogether. Signed-off-by: David Oberhollenzer --- include/sqfs/block.h | 15 ++++++++++++++- lib/sqfs/block_processor/common.c | 9 +++++++-- 2 files changed, 21 insertions(+), 3 deletions(-) diff --git a/include/sqfs/block.h b/include/sqfs/block.h index 7cc815c..582f128 100644 --- a/include/sqfs/block.h +++ b/include/sqfs/block.h @@ -96,6 +96,19 @@ typedef enum { */ SQFS_BLK_DONT_DEDUPLICATE = 0x0008, + /** + * @brief Supress sparse block detection. + * + * If set, sparse blocks are no longer checked and flagged as such and + * are instead processed like normal blocks. + */ + SQFS_BLK_IGNORE_SPARSE = 0x0010, + + /** + * @brief Don't compute block data checksums. + */ + SQFS_BLK_DONT_HASH = 0x0020, + /** * @brief Set by the @ref sqfs_block_processor_t if it determines a * block of a file to be sparse, i.e. only zero bytes. @@ -135,7 +148,7 @@ typedef enum { /** * @brief The combination of all flags that are user settable. */ - SQFS_BLK_USER_SETTABLE_FLAGS = 0x000F, + SQFS_BLK_USER_SETTABLE_FLAGS = 0x003F, } SQFS_BLK_FLAGS; #endif /* SQFS_BLOCK_H */ diff --git a/lib/sqfs/block_processor/common.c b/lib/sqfs/block_processor/common.c index bfcc3d5..b40ec0f 100644 --- a/lib/sqfs/block_processor/common.c +++ b/lib/sqfs/block_processor/common.c @@ -144,12 +144,17 @@ static int process_block(sqfs_block_t *block, sqfs_compressor_t *cmp, } } - if (is_zero_block(block->data, block->size)) { + if (!(block->flags & SQFS_BLK_IGNORE_SPARSE) && + is_zero_block(block->data, block->size)) { block->flags |= SQFS_BLK_IS_SPARSE; return 0; } - block->checksum = xxh32(block->data, block->size); + if (block->flags & SQFS_BLK_DONT_HASH) { + block->checksum = 0; + } else { + block->checksum = xxh32(block->data, block->size); + } if (block->flags & (SQFS_BLK_IS_FRAGMENT | SQFS_BLK_DONT_COMPRESS)) return 0; -- cgit v1.2.3