summaryrefslogtreecommitdiff
path: root/lib/sqfs/data_writer
diff options
context:
space:
mode:
authorDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-09-25 07:28:04 +0200
committerDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-09-25 07:29:11 +0200
commitedac31f28863ae9f1b310d971fb194959c42c916 (patch)
treed9d81491e442123d776c6265795db47247ee6346 /lib/sqfs/data_writer
parent9434bdfaedb733e1441d87fedde8056efeda7145 (diff)
Rename block processor to sqfs_data_writer_t
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'lib/sqfs/data_writer')
-rw-r--r--lib/sqfs/data_writer/block.c131
-rw-r--r--lib/sqfs/data_writer/common.c157
-rw-r--r--lib/sqfs/data_writer/fragment.c128
-rw-r--r--lib/sqfs/data_writer/internal.h137
-rw-r--r--lib/sqfs/data_writer/pthread.c332
-rw-r--r--lib/sqfs/data_writer/serial.c96
6 files changed, 981 insertions, 0 deletions
diff --git a/lib/sqfs/data_writer/block.c b/lib/sqfs/data_writer/block.c
new file mode 100644
index 0000000..9461737
--- /dev/null
+++ b/lib/sqfs/data_writer/block.c
@@ -0,0 +1,131 @@
+/* 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_data_writer_t *proc, uint64_t offset,
+ uint32_t size, uint32_t 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_data_writer_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 allign_file(sqfs_data_writer_t *proc, sqfs_block_t *blk)
+{
+ if (!(blk->flags & SQFS_BLK_ALLIGN))
+ return 0;
+
+ return padd_sqfs(proc->file, proc->file->get_size(proc->file),
+ proc->devblksz);
+}
+
+int process_completed_block(sqfs_data_writer_t *proc, sqfs_block_t *blk)
+{
+ size_t start, count;
+ uint64_t offset;
+ uint32_t out;
+ int err;
+
+ if (blk->flags & SQFS_BLK_FIRST_BLOCK) {
+ proc->start = proc->file->get_size(proc->file);
+ proc->file_start = proc->num_blocks;
+
+ err = allign_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) {
+ offset = htole64(offset);
+ proc->fragments[blk->index].start_offset = offset;
+ proc->fragments[blk->index].pad0 = 0;
+ proc->fragments[blk->index].size = htole32(out);
+ } else {
+ blk->inode->block_sizes[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 (blk->flags & SQFS_BLK_LAST_BLOCK) {
+ err = allign_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) {
+ offset = start + count;
+
+ if (offset >= proc->file_start) {
+ proc->num_blocks = offset;
+ } else {
+ proc->num_blocks = proc->file_start;
+ }
+
+ err = proc->file->truncate(proc->file, proc->start);
+ if (err)
+ return err;
+ }
+ }
+
+ return 0;
+}
diff --git a/lib/sqfs/data_writer/common.c b/lib/sqfs/data_writer/common.c
new file mode 100644
index 0000000..51acc1e
--- /dev/null
+++ b/lib/sqfs/data_writer/common.c
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * common.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+void free_blk_list(sqfs_block_t *list)
+{
+ sqfs_block_t *it;
+
+ while (list != NULL) {
+ it = list;
+ list = list->next;
+ free(it);
+ }
+}
+
+int data_writer_init(sqfs_data_writer_t *proc, size_t max_block_size,
+ sqfs_compressor_t *cmp, unsigned int num_workers,
+ size_t max_backlog, size_t devblksz, sqfs_file_t *file)
+{
+ proc->max_block_size = max_block_size;
+ proc->num_workers = num_workers;
+ proc->max_backlog = max_backlog;
+ proc->devblksz = devblksz;
+ proc->cmp = cmp;
+ proc->file = file;
+ proc->max_blocks = INIT_BLOCK_COUNT;
+ proc->frag_list_max = INIT_BLOCK_COUNT;
+
+ proc->blocks = alloc_array(sizeof(proc->blocks[0]), proc->max_blocks);
+ if (proc->blocks == NULL)
+ return -1;
+
+ proc->frag_list = alloc_array(sizeof(proc->frag_list[0]),
+ proc->frag_list_max);
+ if (proc->frag_list == NULL)
+ return -1;
+
+ return 0;
+}
+
+void data_writer_cleanup(sqfs_data_writer_t *proc)
+{
+ free_blk_list(proc->queue);
+ free_blk_list(proc->done);
+ free(proc->frag_block);
+ free(proc->frag_list);
+ free(proc->fragments);
+ free(proc->blocks);
+ free(proc);
+}
+
+void data_writer_store_done(sqfs_data_writer_t *proc, sqfs_block_t *blk,
+ int status)
+{
+ sqfs_block_t *it = proc->done, *prev = NULL;
+
+ while (it != NULL) {
+ if (it->sequence_number >= blk->sequence_number)
+ break;
+ prev = it;
+ it = it->next;
+ }
+
+ if (prev == NULL) {
+ blk->next = proc->done;
+ proc->done = blk;
+ } else {
+ blk->next = prev->next;
+ prev->next = blk;
+ }
+
+ if (status != 0 && proc->status == 0)
+ proc->status = status;
+
+ proc->backlog -= 1;
+}
+
+sqfs_block_t *data_writer_next_work_item(sqfs_data_writer_t *proc)
+{
+ sqfs_block_t *blk;
+
+ if (proc->status != 0)
+ return NULL;
+
+ blk = proc->queue;
+ proc->queue = blk->next;
+ blk->next = NULL;
+
+ if (proc->queue == NULL)
+ proc->queue_last = NULL;
+
+ return blk;
+}
+
+int data_writer_do_block(sqfs_block_t *block, sqfs_compressor_t *cmp,
+ uint8_t *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;
+}
+
+int sqfs_data_writer_write_fragment_table(sqfs_data_writer_t *proc,
+ sqfs_super_t *super)
+{
+ uint64_t start;
+ size_t size;
+ int ret;
+
+ if (proc->num_fragments == 0) {
+ super->fragment_entry_count = 0;
+ super->fragment_table_start = 0xFFFFFFFFFFFFFFFFUL;
+ super->flags &= ~SQFS_FLAG_ALWAYS_FRAGMENTS;
+ super->flags |= SQFS_FLAG_NO_FRAGMENTS;
+ return 0;
+ }
+
+ size = sizeof(proc->fragments[0]) * proc->num_fragments;
+ ret = sqfs_write_table(proc->file, proc->cmp,
+ proc->fragments, size, &start);
+ if (ret)
+ return ret;
+
+ super->flags &= ~SQFS_FLAG_NO_FRAGMENTS;
+ super->flags |= SQFS_FLAG_ALWAYS_FRAGMENTS;
+ super->fragment_entry_count = proc->num_fragments;
+ super->fragment_table_start = start;
+ return 0;
+}
diff --git a/lib/sqfs/data_writer/fragment.c b/lib/sqfs/data_writer/fragment.c
new file mode 100644
index 0000000..e4fe9b4
--- /dev/null
+++ b/lib/sqfs/data_writer/fragment.c
@@ -0,0 +1,128 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * fragtbl.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+static int grow_fragment_table(sqfs_data_writer_t *proc)
+{
+ size_t newsz;
+ void *new;
+
+ if (proc->num_fragments >= proc->max_fragments) {
+ newsz = proc->max_fragments ? proc->max_fragments * 2 : 16;
+
+ new = realloc(proc->fragments,
+ sizeof(proc->fragments[0]) * newsz);
+
+ if (new == NULL)
+ return SQFS_ERROR_ALLOC;
+
+ proc->max_fragments = newsz;
+ proc->fragments = new;
+ }
+
+ return 0;
+}
+
+static int grow_deduplication_list(sqfs_data_writer_t *proc)
+{
+ size_t new_sz;
+ void *new;
+
+ if (proc->frag_list_num == proc->frag_list_max) {
+ new_sz = proc->frag_list_max * 2;
+ new = realloc(proc->frag_list,
+ sizeof(proc->frag_list[0]) * new_sz);
+
+ if (new == NULL)
+ return SQFS_ERROR_ALLOC;
+
+ proc->frag_list = new;
+ proc->frag_list_max = new_sz;
+ }
+
+ return 0;
+}
+
+static int store_fragment(sqfs_data_writer_t *proc, sqfs_block_t *frag,
+ uint64_t hash)
+{
+ int err = grow_deduplication_list(proc);
+
+ if (err)
+ return err;
+
+ proc->frag_list[proc->frag_list_num].index = proc->frag_block->index;
+ proc->frag_list[proc->frag_list_num].offset = proc->frag_block->size;
+ proc->frag_list[proc->frag_list_num].hash = hash;
+ proc->frag_list_num += 1;
+
+ sqfs_inode_set_frag_location(frag->inode, proc->frag_block->index,
+ proc->frag_block->size);
+
+ memcpy(proc->frag_block->data + proc->frag_block->size,
+ frag->data, frag->size);
+
+ proc->frag_block->flags |= (frag->flags & SQFS_BLK_DONT_COMPRESS);
+ proc->frag_block->size += frag->size;
+ return 0;
+}
+
+int process_completed_fragment(sqfs_data_writer_t *proc, sqfs_block_t *frag,
+ sqfs_block_t **blk_out)
+{
+ uint64_t hash;
+ size_t i, size;
+ int err;
+
+ hash = MK_BLK_HASH(frag->checksum, frag->size);
+
+ for (i = 0; i < proc->frag_list_num; ++i) {
+ if (proc->frag_list[i].hash == hash) {
+ sqfs_inode_set_frag_location(frag->inode,
+ proc->frag_list[i].index,
+ proc->frag_list[i].offset);
+ return 0;
+ }
+ }
+
+ if (proc->frag_block != NULL) {
+ size = proc->frag_block->size + frag->size;
+
+ if (size > proc->max_block_size) {
+ *blk_out = proc->frag_block;
+ proc->frag_block = NULL;
+ }
+ }
+
+ if (proc->frag_block == NULL) {
+ size = sizeof(sqfs_block_t) + proc->max_block_size;
+
+ err = grow_fragment_table(proc);
+ if (err)
+ goto fail;
+
+ proc->frag_block = calloc(1, size);
+ if (proc->frag_block == NULL) {
+ err = SQFS_ERROR_ALLOC;
+ goto fail;
+ }
+
+ proc->frag_block->index = proc->num_fragments++;
+ proc->frag_block->flags = SQFS_BLK_FRAGMENT_BLOCK;
+ }
+
+ err = store_fragment(proc, frag, hash);
+ if (err)
+ goto fail;
+
+ return 0;
+fail:
+ free(*blk_out);
+ *blk_out = NULL;
+ return err;
+}
diff --git a/lib/sqfs/data_writer/internal.h b/lib/sqfs/data_writer/internal.h
new file mode 100644
index 0000000..10cc82c
--- /dev/null
+++ b/lib/sqfs/data_writer/internal.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * internal.h
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#ifndef INTERNAL_H
+#define INTERNAL_H
+
+#include "config.h"
+
+#include "sqfs/data_writer.h"
+#include "sqfs/compress.h"
+#include "sqfs/inode.h"
+#include "sqfs/table.h"
+#include "sqfs/error.h"
+#include "sqfs/data.h"
+#include "sqfs/io.h"
+#include "util.h"
+
+#include <string.h>
+#include <stdlib.h>
+#include <zlib.h>
+
+#ifdef WITH_PTHREAD
+#include <pthread.h>
+#endif
+
+
+#define MK_BLK_HASH(chksum, size) \
+ (((uint64_t)(size) << 32) | (uint64_t)(chksum))
+
+#define INIT_BLOCK_COUNT (128)
+
+
+typedef struct {
+ uint64_t offset;
+ uint64_t hash;
+} blk_info_t;
+
+typedef struct {
+ uint32_t index;
+ uint32_t offset;
+ uint64_t hash;
+} frag_info_t;
+
+
+#ifdef WITH_PTHREAD
+typedef struct {
+ sqfs_data_writer_t *shared;
+ sqfs_compressor_t *cmp;
+ pthread_t thread;
+ uint8_t scratch[];
+} compress_worker_t;
+#endif
+
+struct sqfs_data_writer_t {
+ /* synchronization primitives */
+#ifdef WITH_PTHREAD
+ pthread_mutex_t mtx;
+ pthread_cond_t queue_cond;
+ pthread_cond_t done_cond;
+#endif
+
+ /* needs rw access by worker and main thread */
+ sqfs_block_t *queue;
+ sqfs_block_t *queue_last;
+
+ sqfs_block_t *done;
+ size_t backlog;
+ int status;
+
+ /* used by main thread only */
+ uint32_t enqueue_id;
+ uint32_t dequeue_id;
+
+ unsigned int num_workers;
+ size_t max_backlog;
+
+ size_t devblksz;
+ sqfs_file_t *file;
+
+ sqfs_fragment_t *fragments;
+ size_t num_fragments;
+ size_t max_fragments;
+
+ uint64_t start;
+
+ size_t file_start;
+ size_t num_blocks;
+ size_t max_blocks;
+ blk_info_t *blocks;
+ sqfs_compressor_t *cmp;
+
+ sqfs_block_t *frag_block;
+ frag_info_t *frag_list;
+ size_t frag_list_num;
+ size_t frag_list_max;
+
+ /* used only by workers */
+ size_t max_block_size;
+
+#ifdef WITH_PTHREAD
+ compress_worker_t *workers[];
+#else
+ uint8_t scratch[];
+#endif
+};
+
+SQFS_INTERNAL int process_completed_block(sqfs_data_writer_t *proc,
+ sqfs_block_t *block);
+
+SQFS_INTERNAL
+int process_completed_fragment(sqfs_data_writer_t *proc, sqfs_block_t *frag,
+ sqfs_block_t **blk_out);
+
+SQFS_INTERNAL void free_blk_list(sqfs_block_t *list);
+
+SQFS_INTERNAL
+int data_writer_init(sqfs_data_writer_t *proc, size_t max_block_size,
+ sqfs_compressor_t *cmp, unsigned int num_workers,
+ size_t max_backlog, size_t devblksz, sqfs_file_t *file);
+
+SQFS_INTERNAL void data_writer_cleanup(sqfs_data_writer_t *proc);
+
+SQFS_INTERNAL
+void data_writer_store_done(sqfs_data_writer_t *proc, sqfs_block_t *blk,
+ int status);
+
+SQFS_INTERNAL
+sqfs_block_t *data_writer_next_work_item(sqfs_data_writer_t *proc);
+
+SQFS_INTERNAL
+int data_writer_do_block(sqfs_block_t *block, sqfs_compressor_t *cmp,
+ uint8_t *scratch, size_t scratch_size);
+
+#endif /* INTERNAL_H */
diff --git a/lib/sqfs/data_writer/pthread.c b/lib/sqfs/data_writer/pthread.c
new file mode 100644
index 0000000..3170c11
--- /dev/null
+++ b/lib/sqfs/data_writer/pthread.c
@@ -0,0 +1,332 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * pthread.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+static void *worker_proc(void *arg)
+{
+ compress_worker_t *worker = arg;
+ sqfs_data_writer_t *shared = worker->shared;
+ sqfs_block_t *blk = NULL;
+ int status = 0;
+
+ for (;;) {
+ pthread_mutex_lock(&shared->mtx);
+ if (blk != NULL) {
+ data_writer_store_done(shared, blk, status);
+ pthread_cond_broadcast(&shared->done_cond);
+ }
+
+ while (shared->queue == NULL && shared->status == 0)
+ pthread_cond_wait(&shared->queue_cond, &shared->mtx);
+
+ blk = data_writer_next_work_item(shared);
+ pthread_mutex_unlock(&shared->mtx);
+
+ if (blk == NULL)
+ break;
+
+ status = data_writer_do_block(blk, worker->cmp,
+ worker->scratch,
+ shared->max_block_size);
+ }
+ return NULL;
+}
+
+sqfs_data_writer_t *sqfs_data_writer_create(size_t max_block_size,
+ sqfs_compressor_t *cmp,
+ unsigned int num_workers,
+ size_t max_backlog,
+ size_t devblksz,
+ sqfs_file_t *file)
+{
+ sqfs_data_writer_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)
+ return NULL;
+
+ proc->mtx = (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;
+ proc->queue_cond = (pthread_cond_t)PTHREAD_COND_INITIALIZER;
+ proc->done_cond = (pthread_cond_t)PTHREAD_COND_INITIALIZER;
+
+ if (data_writer_init(proc, max_block_size, cmp, num_workers,
+ max_backlog, devblksz, file)) {
+ goto fail_init;
+ }
+
+ 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)
+ 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)
+ goto fail_thread;
+ }
+
+ return proc;
+fail_thread:
+ pthread_mutex_lock(&proc->mtx);
+ proc->status = -1;
+ 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);
+ pthread_cond_destroy(&proc->queue_cond);
+ pthread_mutex_destroy(&proc->mtx);
+ data_writer_cleanup(proc);
+ return NULL;
+}
+
+void sqfs_data_writer_destroy(sqfs_data_writer_t *proc)
+{
+ unsigned int i;
+
+ pthread_mutex_lock(&proc->mtx);
+ proc->status = -1;
+ 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);
+
+ data_writer_cleanup(proc);
+}
+
+static void append_to_work_queue(sqfs_data_writer_t *proc,
+ sqfs_block_t *block)
+{
+ if (proc->queue_last == NULL) {
+ proc->queue = proc->queue_last = block;
+ } else {
+ proc->queue_last->next = block;
+ proc->queue_last = block;
+ }
+
+ block->sequence_number = proc->enqueue_id++;
+ block->next = NULL;
+ proc->backlog += 1;
+ pthread_cond_broadcast(&proc->queue_cond);
+}
+
+static int test_and_set_status(sqfs_data_writer_t *proc, int status)
+{
+ pthread_mutex_lock(&proc->mtx);
+ if (proc->status == 0) {
+ proc->status = status;
+ } else {
+ status = proc->status;
+ }
+ pthread_cond_broadcast(&proc->queue_cond);
+ return status;
+}
+
+static sqfs_block_t *try_dequeue(sqfs_data_writer_t *proc)
+{
+ sqfs_block_t *queue, *it, *prev;
+
+ 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 = NULL;
+ } else {
+ queue = proc->done;
+ prev->next = NULL;
+ proc->done = it;
+ }
+
+ return queue;
+}
+
+static sqfs_block_t *queue_merge(sqfs_block_t *lhs, sqfs_block_t *rhs)
+{
+ sqfs_block_t *it, *head = NULL, **next_ptr = &head;
+
+ while (lhs != NULL && rhs != NULL) {
+ if (lhs->sequence_number <= rhs->sequence_number) {
+ it = lhs;
+ lhs = lhs->next;
+ } else {
+ it = rhs;
+ rhs = rhs->next;
+ }
+
+ *next_ptr = it;
+ next_ptr = &it->next;
+ }
+
+ it = (lhs != NULL ? lhs : rhs);
+ *next_ptr = it;
+ return head;
+}
+
+static int process_done_queue(sqfs_data_writer_t *proc, sqfs_block_t *queue)
+{
+ sqfs_block_t *it, *block = NULL;
+ int status = 0;
+
+ while (queue != NULL && status == 0) {
+ it = queue;
+ queue = it->next;
+
+ if (it->flags & SQFS_BLK_IS_FRAGMENT) {
+ block = NULL;
+ status = process_completed_fragment(proc, it, &block);
+
+ if (block != NULL && status == 0) {
+ pthread_mutex_lock(&proc->mtx);
+ proc->dequeue_id = it->sequence_number;
+ block->sequence_number = it->sequence_number;
+
+ if (proc->queue == NULL) {
+ proc->queue = block;
+ proc->queue_last = block;
+ } else {
+ block->next = proc->queue;
+ proc->queue = block;
+ }
+
+ proc->backlog += 1;
+ proc->done = queue_merge(queue, proc->done);
+ pthread_cond_broadcast(&proc->queue_cond);
+ pthread_mutex_unlock(&proc->mtx);
+
+ queue = NULL;
+ } else {
+ free(block);
+ }
+ } else {
+ status = process_completed_block(proc, it);
+ }
+
+ free(it);
+ }
+
+ free_blk_list(queue);
+ return status;
+}
+
+int sqfs_data_writer_enqueue(sqfs_data_writer_t *proc, sqfs_block_t *block)
+{
+ sqfs_block_t *queue;
+ int status;
+
+ if (block->flags & ~SQFS_BLK_USER_SETTABLE_FLAGS) {
+ free(block);
+ return test_and_set_status(proc, SQFS_ERROR_UNSUPPORTED);
+ }
+
+ pthread_mutex_lock(&proc->mtx);
+ while (proc->backlog > proc->max_backlog && proc->status == 0)
+ pthread_cond_wait(&proc->done_cond, &proc->mtx);
+
+ if (proc->status != 0) {
+ status = proc->status;
+ pthread_mutex_unlock(&proc->mtx);
+ free(block);
+ return status;
+ }
+
+ append_to_work_queue(proc, block);
+ block = NULL;
+
+ queue = try_dequeue(proc);
+ pthread_mutex_unlock(&proc->mtx);
+
+ status = process_done_queue(proc, queue);
+ if (status != 0)
+ return test_and_set_status(proc, status);
+
+ return 0;
+}
+
+int sqfs_data_writer_finish(sqfs_data_writer_t *proc)
+{
+ sqfs_block_t *queue;
+ int status = 0;
+
+ for (;;) {
+ pthread_mutex_lock(&proc->mtx);
+ while (proc->backlog > 0 && proc->status == 0)
+ pthread_cond_wait(&proc->done_cond, &proc->mtx);
+
+ if (proc->status != 0) {
+ status = proc->status;
+ pthread_mutex_unlock(&proc->mtx);
+ return status;
+ }
+
+ queue = proc->done;
+ proc->done = NULL;
+ pthread_mutex_unlock(&proc->mtx);
+
+ if (queue == NULL) {
+ if (proc->frag_block != NULL) {
+ append_to_work_queue(proc, proc->frag_block);
+ proc->frag_block = NULL;
+ continue;
+ }
+ break;
+ }
+
+ status = process_done_queue(proc, queue);
+ if (status != 0)
+ return status;
+ }
+
+ return 0;
+}
diff --git a/lib/sqfs/data_writer/serial.c b/lib/sqfs/data_writer/serial.c
new file mode 100644
index 0000000..38dcc58
--- /dev/null
+++ b/lib/sqfs/data_writer/serial.c
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * serial.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "internal.h"
+
+sqfs_data_writer_t *sqfs_data_writer_create(size_t max_block_size,
+ sqfs_compressor_t *cmp,
+ unsigned int num_workers,
+ size_t max_backlog,
+ size_t devblksz,
+ sqfs_file_t *file)
+{
+ sqfs_data_writer_t *proc;
+
+ proc = alloc_flex(sizeof(*proc), 1, max_block_size);
+
+ if (proc == NULL)
+ return NULL;
+
+ if (data_writer_init(proc, max_block_size, cmp, num_workers,
+ max_backlog, devblksz, file)) {
+ data_writer_cleanup(proc);
+ return NULL;
+ }
+
+ return proc;
+}
+
+void sqfs_data_writer_destroy(sqfs_data_writer_t *proc)
+{
+ data_writer_cleanup(proc);
+}
+
+int sqfs_data_writer_enqueue(sqfs_data_writer_t *proc, sqfs_block_t *block)
+{
+ sqfs_block_t *fragblk = NULL;
+
+ if (proc->status != 0) {
+ free(block);
+ return proc->status;
+ }
+
+ if (block->flags & ~SQFS_BLK_USER_SETTABLE_FLAGS) {
+ proc->status = SQFS_ERROR_UNSUPPORTED;
+ free(block);
+ return proc->status;
+ }
+
+ if (block->flags & SQFS_BLK_IS_FRAGMENT) {
+ block->checksum = crc32(0, block->data, block->size);
+
+ proc->status = process_completed_fragment(proc, block,
+ &fragblk);
+ free(block);
+
+ if (proc->status != 0) {
+ free(fragblk);
+ return proc->status;
+ }
+
+ if (fragblk == NULL)
+ return 0;
+
+ block = fragblk;
+ }
+
+ proc->status = data_writer_do_block(block, proc->cmp, proc->scratch,
+ proc->max_block_size);
+
+ if (proc->status == 0)
+ proc->status = process_completed_block(proc, block);
+
+ free(block);
+ return proc->status;
+}
+
+int sqfs_data_writer_finish(sqfs_data_writer_t *proc)
+{
+ if (proc->status != 0 || proc->frag_block == NULL)
+ return proc->status;
+
+ proc->status = data_writer_do_block(proc->frag_block, proc->cmp,
+ proc->scratch,
+ proc->max_block_size);
+
+ if (proc->status == 0)
+ proc->status = process_completed_block(proc, proc->frag_block);
+
+ free(proc->frag_block);
+ proc->frag_block = NULL;
+ return proc->status;
+}