From 6391ed9a18caf89ade24c05083569c66d8daa33b Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Thu, 5 Sep 2019 15:44:56 +0200 Subject: Move block processor from compressor to libsquashfs code Signed-off-by: David Oberhollenzer --- lib/Makemodule.am | 6 +- lib/sqfs/block_processor.c | 72 +++++++ lib/sqfs/block_processor_parallel.c | 340 +++++++++++++++++++++++++++++++ lib/sqfs/comp/block_processor.c | 72 ------- lib/sqfs/comp/block_processor_parallel.c | 340 ------------------------------- lib/sqfs/comp/process_block.c | 38 ---- lib/sqfs/process_block.c | 38 ++++ 7 files changed, 453 insertions(+), 453 deletions(-) create mode 100644 lib/sqfs/block_processor.c create mode 100644 lib/sqfs/block_processor_parallel.c delete mode 100644 lib/sqfs/comp/block_processor.c delete mode 100644 lib/sqfs/comp/block_processor_parallel.c delete mode 100644 lib/sqfs/comp/process_block.c create mode 100644 lib/sqfs/process_block.c diff --git a/lib/Makemodule.am b/lib/Makemodule.am index 6938fd7..bdb23a8 100644 --- a/lib/Makemodule.am +++ b/lib/Makemodule.am @@ -57,7 +57,7 @@ libsquashfs_la_SOURCES += lib/sqfs/readdir.c libsquashfs_la_SOURCES += lib/sqfs/xattr.c lib/sqfs/xattr_reader.c libsquashfs_la_SOURCES += lib/sqfs/read_table.c libsquashfs_la_SOURCES += lib/sqfs/comp/compressor.c lib/sqfs/comp/internal.h -libsquashfs_la_SOURCES += lib/sqfs/comp/process_block.c +libsquashfs_la_SOURCES += lib/sqfs/process_block.c libsquashfs_la_CPPFLAGS = $(AM_CPPFLAGS) libsquashfs_la_CFLAGS = $(AM_CFLAGS) $(PTHREAD_CFLAGS) $(ZLIB_CFLAGS) libsquashfs_la_CFLAGS += $(XZ_CFLAGS) $(LZO_CFLAGS) $(LZ4_CFLAGS) @@ -66,9 +66,9 @@ libsquashfs_la_LIBADD = $(XZ_LIBS) $(ZLIB_LIBS) $(LZO_LIBS) $(LZ4_LIBS) libsquashfs_la_LIBADD += $(ZSTD_LIBS) $(PTHREAD_LIBS) libutil.la if HAVE_PTHREAD -libsquashfs_la_SOURCES += lib/sqfs/comp/block_processor_parallel.c +libsquashfs_la_SOURCES += lib/sqfs/block_processor_parallel.c else -libsquashfs_la_SOURCES += lib/sqfs/comp/block_processor.c +libsquashfs_la_SOURCES += lib/sqfs/block_processor.c endif if WITH_GZIP diff --git a/lib/sqfs/block_processor.c b/lib/sqfs/block_processor.c new file mode 100644 index 0000000..3a6926c --- /dev/null +++ b/lib/sqfs/block_processor.c @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * block_processor.c + * + * Copyright (C) 2019 David Oberhollenzer + */ +#include "config.h" + +#include "sqfs/block_processor.h" +#include "util.h" + +#include +#include +#include + +struct block_processor_t { + size_t max_block_size; + compressor_t *cmp; + block_cb cb; + void *user; + int status; + + uint8_t scratch[]; +}; + +block_processor_t *block_processor_create(size_t max_block_size, + compressor_t *cmp, + unsigned int num_workers, + void *user, + block_cb callback) +{ + block_processor_t *proc = alloc_flex(sizeof(*proc), 1, max_block_size); + (void)num_workers; + + if (proc == NULL) { + perror("Creating block processor"); + return NULL; + } + + proc->max_block_size = max_block_size; + proc->cmp = cmp; + proc->cb = callback; + proc->user = user; + return proc; +} + +void block_processor_destroy(block_processor_t *proc) +{ + free(proc); +} + +int block_processor_enqueue(block_processor_t *proc, block_t *block) +{ + if (process_block(block, proc->cmp, + proc->scratch, proc->max_block_size)) + goto fail; + + if (proc->cb(proc->user, block)) + goto fail; + + free(block); + return 0; +fail: + free(block); + proc->status = -1; + return -1; +} + +int block_processor_finish(block_processor_t *proc) +{ + return proc->status; +} diff --git a/lib/sqfs/block_processor_parallel.c b/lib/sqfs/block_processor_parallel.c new file mode 100644 index 0000000..a4e0f6e --- /dev/null +++ b/lib/sqfs/block_processor_parallel.c @@ -0,0 +1,340 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * block_processor.c + * + * Copyright (C) 2019 David Oberhollenzer + */ +#include "config.h" + +#include "sqfs/block_processor.h" +#include "util.h" + +#include +#include +#include +#include + +#define MAX_BACKLOG_FACTOR (10) + +typedef struct { + block_processor_t *shared; + compressor_t *cmp; + pthread_t thread; + uint8_t scratch[]; +} compress_worker_t; + +struct block_processor_t { + pthread_mutex_t mtx; + pthread_cond_t queue_cond; + pthread_cond_t done_cond; + + /* needs rw access by worker and main thread */ + block_t *queue; + block_t *queue_last; + + block_t *done; + bool terminate; + size_t backlog; + + /* used by main thread only */ + uint32_t enqueue_id; + uint32_t dequeue_id; + + unsigned int num_workers; + block_cb cb; + void *user; + int status; + + /* used only by workers */ + size_t max_block_size; + + compress_worker_t *workers[]; +}; + +static void store_completed_block(block_processor_t *shared, block_t *blk) +{ + block_t *it = shared->done, *prev = NULL; + + while (it != NULL) { + if (it->sequence_number >= blk->sequence_number) + break; + prev = it; + it = it->next; + } + + if (prev == NULL) { + blk->next = shared->done; + shared->done = blk; + } else { + blk->next = prev->next; + prev->next = blk; + } +} + +static void *worker_proc(void *arg) +{ + compress_worker_t *worker = arg; + block_processor_t *shared = worker->shared; + block_t *blk = NULL; + + for (;;) { + pthread_mutex_lock(&shared->mtx); + if (blk != NULL) { + store_completed_block(shared, blk); + shared->backlog -= 1; + pthread_cond_broadcast(&shared->done_cond); + } + + while (shared->queue == NULL && !shared->terminate) { + pthread_cond_wait(&shared->queue_cond, + &shared->mtx); + } + + if (shared->terminate) { + pthread_mutex_unlock(&shared->mtx); + break; + } + + blk = shared->queue; + shared->queue = blk->next; + blk->next = NULL; + + if (shared->queue == NULL) + shared->queue_last = NULL; + pthread_mutex_unlock(&shared->mtx); + + if (process_block(blk, worker->cmp, worker->scratch, + shared->max_block_size)) { + blk->flags |= BLK_COMPRESS_ERROR; + } + } + return NULL; +} + +block_processor_t *block_processor_create(size_t max_block_size, + compressor_t *cmp, + unsigned int num_workers, + void *user, + block_cb callback) +{ + block_processor_t *proc; + unsigned int i; + int ret; + + if (num_workers < 1) + num_workers = 1; + + proc = alloc_flex(sizeof(*proc), + sizeof(proc->workers[0]), num_workers); + if (proc == NULL) { + perror("Creating block processor"); + return NULL; + } + + proc->max_block_size = max_block_size; + proc->cb = callback; + proc->user = user; + proc->num_workers = num_workers; + + if (pthread_mutex_init(&proc->mtx, NULL)) { + perror("Creating block processor mutex"); + goto fail_free; + } + + if (pthread_cond_init(&proc->queue_cond, NULL)) { + perror("Creating block processor conditional"); + goto fail_mtx; + } + + if (pthread_cond_init(&proc->done_cond, NULL)) { + perror("Creating block processor completion conditional"); + goto fail_cond; + } + + for (i = 0; i < num_workers; ++i) { + proc->workers[i] = alloc_flex(sizeof(compress_worker_t), + 1, max_block_size); + + if (proc->workers[i] == NULL) { + perror("Creating block worker data"); + goto fail_init; + } + + proc->workers[i]->shared = proc; + proc->workers[i]->cmp = cmp->create_copy(cmp); + + if (proc->workers[i]->cmp == NULL) + goto fail_init; + } + + for (i = 0; i < num_workers; ++i) { + ret = pthread_create(&proc->workers[i]->thread, NULL, + worker_proc, proc->workers[i]); + + if (ret != 0) { + perror("Creating block processor thread"); + goto fail_thread; + } + } + + return proc; +fail_thread: + pthread_mutex_lock(&proc->mtx); + proc->terminate = true; + pthread_cond_broadcast(&proc->queue_cond); + pthread_mutex_unlock(&proc->mtx); + + for (i = 0; i < num_workers; ++i) { + if (proc->workers[i]->thread > 0) { + pthread_join(proc->workers[i]->thread, NULL); + } + } +fail_init: + for (i = 0; i < num_workers; ++i) { + if (proc->workers[i] != NULL) { + if (proc->workers[i]->cmp != NULL) { + proc->workers[i]->cmp-> + destroy(proc->workers[i]->cmp); + } + + free(proc->workers[i]); + } + } + pthread_cond_destroy(&proc->done_cond); +fail_cond: + pthread_cond_destroy(&proc->queue_cond); +fail_mtx: + pthread_mutex_destroy(&proc->mtx); +fail_free: + free(proc); + return NULL; +} + +void block_processor_destroy(block_processor_t *proc) +{ + unsigned int i; + block_t *blk; + + pthread_mutex_lock(&proc->mtx); + proc->terminate = true; + pthread_cond_broadcast(&proc->queue_cond); + pthread_mutex_unlock(&proc->mtx); + + for (i = 0; i < proc->num_workers; ++i) { + pthread_join(proc->workers[i]->thread, NULL); + + proc->workers[i]->cmp->destroy(proc->workers[i]->cmp); + free(proc->workers[i]); + } + + pthread_cond_destroy(&proc->done_cond); + pthread_cond_destroy(&proc->queue_cond); + pthread_mutex_destroy(&proc->mtx); + + while (proc->queue != NULL) { + blk = proc->queue; + proc->queue = blk->next; + free(blk); + } + + while (proc->done != NULL) { + blk = proc->done; + proc->done = blk->next; + free(blk); + } + + free(proc); +} + +static int process_completed_blocks(block_processor_t *proc, block_t *queue) +{ + block_t *it; + + while (queue != NULL) { + it = queue; + queue = queue->next; + + if (it->flags & BLK_COMPRESS_ERROR) { + proc->status = -1; + } else { + if (proc->cb(proc->user, it)) + proc->status = -1; + } + + free(it); + } + + return proc->status; +} + +int block_processor_enqueue(block_processor_t *proc, block_t *block) +{ + block_t *queue = NULL, *it, *prev; + + block->sequence_number = proc->enqueue_id++; + block->next = NULL; + + pthread_mutex_lock(&proc->mtx); + if ((block->flags & BLK_DONT_COMPRESS) && + (block->flags & BLK_DONT_CHECKSUM)) { + store_completed_block(proc, block); + } else { + while (proc->backlog > proc->num_workers * MAX_BACKLOG_FACTOR) + pthread_cond_wait(&proc->done_cond, &proc->mtx); + + if (proc->queue_last == NULL) { + proc->queue = proc->queue_last = block; + } else { + proc->queue_last->next = block; + proc->queue_last = block; + } + + proc->backlog += 1; + } + + it = proc->done; + prev = NULL; + + while (it != NULL && it->sequence_number == proc->dequeue_id) { + prev = it; + it = it->next; + proc->dequeue_id += 1; + } + + if (prev != NULL) { + queue = proc->done; + prev->next = NULL; + proc->done = it; + } + + pthread_cond_broadcast(&proc->queue_cond); + pthread_mutex_unlock(&proc->mtx); + + return process_completed_blocks(proc, queue); +} + +int block_processor_finish(block_processor_t *proc) +{ + block_t *queue, *it; + + pthread_mutex_lock(&proc->mtx); + while (proc->backlog > 0) + pthread_cond_wait(&proc->done_cond, &proc->mtx); + + for (it = proc->done; it != NULL; it = it->next) { + if (it->sequence_number != proc->dequeue_id++) { + pthread_mutex_unlock(&proc->mtx); + goto bug_seqnum; + } + } + + queue = proc->done; + proc->done = NULL; + pthread_mutex_unlock(&proc->mtx); + + return process_completed_blocks(proc, queue); +bug_seqnum: + fputs("[BUG][parallel block processor] " + "gap in sequence numbers!\n", stderr); + return -1; +} diff --git a/lib/sqfs/comp/block_processor.c b/lib/sqfs/comp/block_processor.c deleted file mode 100644 index 3a6926c..0000000 --- a/lib/sqfs/comp/block_processor.c +++ /dev/null @@ -1,72 +0,0 @@ -/* SPDX-License-Identifier: GPL-3.0-or-later */ -/* - * block_processor.c - * - * Copyright (C) 2019 David Oberhollenzer - */ -#include "config.h" - -#include "sqfs/block_processor.h" -#include "util.h" - -#include -#include -#include - -struct block_processor_t { - size_t max_block_size; - compressor_t *cmp; - block_cb cb; - void *user; - int status; - - uint8_t scratch[]; -}; - -block_processor_t *block_processor_create(size_t max_block_size, - compressor_t *cmp, - unsigned int num_workers, - void *user, - block_cb callback) -{ - block_processor_t *proc = alloc_flex(sizeof(*proc), 1, max_block_size); - (void)num_workers; - - if (proc == NULL) { - perror("Creating block processor"); - return NULL; - } - - proc->max_block_size = max_block_size; - proc->cmp = cmp; - proc->cb = callback; - proc->user = user; - return proc; -} - -void block_processor_destroy(block_processor_t *proc) -{ - free(proc); -} - -int block_processor_enqueue(block_processor_t *proc, block_t *block) -{ - if (process_block(block, proc->cmp, - proc->scratch, proc->max_block_size)) - goto fail; - - if (proc->cb(proc->user, block)) - goto fail; - - free(block); - return 0; -fail: - free(block); - proc->status = -1; - return -1; -} - -int block_processor_finish(block_processor_t *proc) -{ - return proc->status; -} diff --git a/lib/sqfs/comp/block_processor_parallel.c b/lib/sqfs/comp/block_processor_parallel.c deleted file mode 100644 index a4e0f6e..0000000 --- a/lib/sqfs/comp/block_processor_parallel.c +++ /dev/null @@ -1,340 +0,0 @@ -/* SPDX-License-Identifier: GPL-3.0-or-later */ -/* - * block_processor.c - * - * Copyright (C) 2019 David Oberhollenzer - */ -#include "config.h" - -#include "sqfs/block_processor.h" -#include "util.h" - -#include -#include -#include -#include - -#define MAX_BACKLOG_FACTOR (10) - -typedef struct { - block_processor_t *shared; - compressor_t *cmp; - pthread_t thread; - uint8_t scratch[]; -} compress_worker_t; - -struct block_processor_t { - pthread_mutex_t mtx; - pthread_cond_t queue_cond; - pthread_cond_t done_cond; - - /* needs rw access by worker and main thread */ - block_t *queue; - block_t *queue_last; - - block_t *done; - bool terminate; - size_t backlog; - - /* used by main thread only */ - uint32_t enqueue_id; - uint32_t dequeue_id; - - unsigned int num_workers; - block_cb cb; - void *user; - int status; - - /* used only by workers */ - size_t max_block_size; - - compress_worker_t *workers[]; -}; - -static void store_completed_block(block_processor_t *shared, block_t *blk) -{ - block_t *it = shared->done, *prev = NULL; - - while (it != NULL) { - if (it->sequence_number >= blk->sequence_number) - break; - prev = it; - it = it->next; - } - - if (prev == NULL) { - blk->next = shared->done; - shared->done = blk; - } else { - blk->next = prev->next; - prev->next = blk; - } -} - -static void *worker_proc(void *arg) -{ - compress_worker_t *worker = arg; - block_processor_t *shared = worker->shared; - block_t *blk = NULL; - - for (;;) { - pthread_mutex_lock(&shared->mtx); - if (blk != NULL) { - store_completed_block(shared, blk); - shared->backlog -= 1; - pthread_cond_broadcast(&shared->done_cond); - } - - while (shared->queue == NULL && !shared->terminate) { - pthread_cond_wait(&shared->queue_cond, - &shared->mtx); - } - - if (shared->terminate) { - pthread_mutex_unlock(&shared->mtx); - break; - } - - blk = shared->queue; - shared->queue = blk->next; - blk->next = NULL; - - if (shared->queue == NULL) - shared->queue_last = NULL; - pthread_mutex_unlock(&shared->mtx); - - if (process_block(blk, worker->cmp, worker->scratch, - shared->max_block_size)) { - blk->flags |= BLK_COMPRESS_ERROR; - } - } - return NULL; -} - -block_processor_t *block_processor_create(size_t max_block_size, - compressor_t *cmp, - unsigned int num_workers, - void *user, - block_cb callback) -{ - block_processor_t *proc; - unsigned int i; - int ret; - - if (num_workers < 1) - num_workers = 1; - - proc = alloc_flex(sizeof(*proc), - sizeof(proc->workers[0]), num_workers); - if (proc == NULL) { - perror("Creating block processor"); - return NULL; - } - - proc->max_block_size = max_block_size; - proc->cb = callback; - proc->user = user; - proc->num_workers = num_workers; - - if (pthread_mutex_init(&proc->mtx, NULL)) { - perror("Creating block processor mutex"); - goto fail_free; - } - - if (pthread_cond_init(&proc->queue_cond, NULL)) { - perror("Creating block processor conditional"); - goto fail_mtx; - } - - if (pthread_cond_init(&proc->done_cond, NULL)) { - perror("Creating block processor completion conditional"); - goto fail_cond; - } - - for (i = 0; i < num_workers; ++i) { - proc->workers[i] = alloc_flex(sizeof(compress_worker_t), - 1, max_block_size); - - if (proc->workers[i] == NULL) { - perror("Creating block worker data"); - goto fail_init; - } - - proc->workers[i]->shared = proc; - proc->workers[i]->cmp = cmp->create_copy(cmp); - - if (proc->workers[i]->cmp == NULL) - goto fail_init; - } - - for (i = 0; i < num_workers; ++i) { - ret = pthread_create(&proc->workers[i]->thread, NULL, - worker_proc, proc->workers[i]); - - if (ret != 0) { - perror("Creating block processor thread"); - goto fail_thread; - } - } - - return proc; -fail_thread: - pthread_mutex_lock(&proc->mtx); - proc->terminate = true; - pthread_cond_broadcast(&proc->queue_cond); - pthread_mutex_unlock(&proc->mtx); - - for (i = 0; i < num_workers; ++i) { - if (proc->workers[i]->thread > 0) { - pthread_join(proc->workers[i]->thread, NULL); - } - } -fail_init: - for (i = 0; i < num_workers; ++i) { - if (proc->workers[i] != NULL) { - if (proc->workers[i]->cmp != NULL) { - proc->workers[i]->cmp-> - destroy(proc->workers[i]->cmp); - } - - free(proc->workers[i]); - } - } - pthread_cond_destroy(&proc->done_cond); -fail_cond: - pthread_cond_destroy(&proc->queue_cond); -fail_mtx: - pthread_mutex_destroy(&proc->mtx); -fail_free: - free(proc); - return NULL; -} - -void block_processor_destroy(block_processor_t *proc) -{ - unsigned int i; - block_t *blk; - - pthread_mutex_lock(&proc->mtx); - proc->terminate = true; - pthread_cond_broadcast(&proc->queue_cond); - pthread_mutex_unlock(&proc->mtx); - - for (i = 0; i < proc->num_workers; ++i) { - pthread_join(proc->workers[i]->thread, NULL); - - proc->workers[i]->cmp->destroy(proc->workers[i]->cmp); - free(proc->workers[i]); - } - - pthread_cond_destroy(&proc->done_cond); - pthread_cond_destroy(&proc->queue_cond); - pthread_mutex_destroy(&proc->mtx); - - while (proc->queue != NULL) { - blk = proc->queue; - proc->queue = blk->next; - free(blk); - } - - while (proc->done != NULL) { - blk = proc->done; - proc->done = blk->next; - free(blk); - } - - free(proc); -} - -static int process_completed_blocks(block_processor_t *proc, block_t *queue) -{ - block_t *it; - - while (queue != NULL) { - it = queue; - queue = queue->next; - - if (it->flags & BLK_COMPRESS_ERROR) { - proc->status = -1; - } else { - if (proc->cb(proc->user, it)) - proc->status = -1; - } - - free(it); - } - - return proc->status; -} - -int block_processor_enqueue(block_processor_t *proc, block_t *block) -{ - block_t *queue = NULL, *it, *prev; - - block->sequence_number = proc->enqueue_id++; - block->next = NULL; - - pthread_mutex_lock(&proc->mtx); - if ((block->flags & BLK_DONT_COMPRESS) && - (block->flags & BLK_DONT_CHECKSUM)) { - store_completed_block(proc, block); - } else { - while (proc->backlog > proc->num_workers * MAX_BACKLOG_FACTOR) - pthread_cond_wait(&proc->done_cond, &proc->mtx); - - if (proc->queue_last == NULL) { - proc->queue = proc->queue_last = block; - } else { - proc->queue_last->next = block; - proc->queue_last = block; - } - - proc->backlog += 1; - } - - it = proc->done; - prev = NULL; - - while (it != NULL && it->sequence_number == proc->dequeue_id) { - prev = it; - it = it->next; - proc->dequeue_id += 1; - } - - if (prev != NULL) { - queue = proc->done; - prev->next = NULL; - proc->done = it; - } - - pthread_cond_broadcast(&proc->queue_cond); - pthread_mutex_unlock(&proc->mtx); - - return process_completed_blocks(proc, queue); -} - -int block_processor_finish(block_processor_t *proc) -{ - block_t *queue, *it; - - pthread_mutex_lock(&proc->mtx); - while (proc->backlog > 0) - pthread_cond_wait(&proc->done_cond, &proc->mtx); - - for (it = proc->done; it != NULL; it = it->next) { - if (it->sequence_number != proc->dequeue_id++) { - pthread_mutex_unlock(&proc->mtx); - goto bug_seqnum; - } - } - - queue = proc->done; - proc->done = NULL; - pthread_mutex_unlock(&proc->mtx); - - return process_completed_blocks(proc, queue); -bug_seqnum: - fputs("[BUG][parallel block processor] " - "gap in sequence numbers!\n", stderr); - return -1; -} diff --git a/lib/sqfs/comp/process_block.c b/lib/sqfs/comp/process_block.c deleted file mode 100644 index a20b56b..0000000 --- a/lib/sqfs/comp/process_block.c +++ /dev/null @@ -1,38 +0,0 @@ -/* SPDX-License-Identifier: GPL-3.0-or-later */ -/* - * process_block.c - * - * Copyright (C) 2019 David Oberhollenzer - */ -#include "config.h" - -#include "sqfs/block_processor.h" -#include "util.h" - -#include -#include - -int process_block(block_t *block, compressor_t *cmp, - uint8_t *scratch, size_t scratch_size) -{ - ssize_t ret; - - if (!(block->flags & BLK_DONT_CHECKSUM)) - block->checksum = crc32(0, block->data, block->size); - - if (!(block->flags & BLK_DONT_COMPRESS)) { - ret = cmp->do_block(cmp, block->data, block->size, - scratch, scratch_size); - - if (ret < 0) - return -1; - - if (ret > 0) { - memcpy(block->data, scratch, ret); - block->size = ret; - block->flags |= BLK_IS_COMPRESSED; - } - } - - return 0; -} diff --git a/lib/sqfs/process_block.c b/lib/sqfs/process_block.c new file mode 100644 index 0000000..a20b56b --- /dev/null +++ b/lib/sqfs/process_block.c @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * process_block.c + * + * Copyright (C) 2019 David Oberhollenzer + */ +#include "config.h" + +#include "sqfs/block_processor.h" +#include "util.h" + +#include +#include + +int process_block(block_t *block, compressor_t *cmp, + uint8_t *scratch, size_t scratch_size) +{ + ssize_t ret; + + if (!(block->flags & BLK_DONT_CHECKSUM)) + block->checksum = crc32(0, block->data, block->size); + + if (!(block->flags & BLK_DONT_COMPRESS)) { + ret = cmp->do_block(cmp, block->data, block->size, + scratch, scratch_size); + + if (ret < 0) + return -1; + + if (ret > 0) { + memcpy(block->data, scratch, ret); + block->size = ret; + block->flags |= BLK_IS_COMPRESSED; + } + } + + return 0; +} -- cgit v1.2.3