Cleanup: move block processor code to sub directory

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 323 insertions, 0 deletions

diff --git a/lib/sqfs/blk_proc/pthread.c b/lib/sqfs/blk_proc/pthread.c
new file mode 100644
index 0000000..a00bf12
--- /dev/null
+++ b/lib/sqfs/blk_proc/pthread.c
@@ -0,0 +1,323 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * block_processor.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#define SQFS_BUILDING_DLL
+#include "config.h"
+
+#include "sqfs/block_processor.h"
+#include "sqfs/compress.h"
+#include "sqfs/error.h"
+#include "util.h"
+
+#include <pthread.h>
+#include <string.h>
+#include <stdlib.h>
+
+typedef struct {
+	sqfs_block_processor_t *shared;
+	sqfs_compressor_t *cmp;
+	pthread_t thread;
+	uint8_t scratch[];
+} compress_worker_t;
+
+struct sqfs_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 */
+	sqfs_block_t *queue;
+	sqfs_block_t *queue_last;
+
+	sqfs_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;
+	sqfs_block_cb cb;
+	void *user;
+	int status;
+	size_t max_backlog;
+
+	/* used only by workers */
+	size_t max_block_size;
+
+	compress_worker_t *workers[];
+};
+
+static void store_completed_block(sqfs_block_processor_t *shared,
+				  sqfs_block_t *blk)
+{
+	sqfs_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;
+	sqfs_block_processor_t *shared = worker->shared;
+	sqfs_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);
+
+		sqfs_block_process(blk, worker->cmp, worker->scratch,
+				   shared->max_block_size);
+	}
+	return NULL;
+}
+
+sqfs_block_processor_t *sqfs_block_processor_create(size_t max_block_size,
+						    sqfs_compressor_t *cmp,
+						    unsigned int num_workers,
+						    size_t max_backlog,
+						    void *user,
+						    sqfs_block_cb callback)
+{
+	sqfs_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)
+		return NULL;
+
+	proc->max_block_size = max_block_size;
+	proc->cb = callback;
+	proc->user = user;
+	proc->num_workers = num_workers;
+	proc->max_backlog = max_backlog;
+	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;
+
+	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->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);
+	pthread_cond_destroy(&proc->queue_cond);
+	pthread_mutex_destroy(&proc->mtx);
+	free(proc);
+	return NULL;
+}
+
+void sqfs_block_processor_destroy(sqfs_block_processor_t *proc)
+{
+	sqfs_block_t *blk;
+	unsigned int i;
+
+	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(sqfs_block_processor_t *proc,
+				    sqfs_block_t *queue)
+{
+	sqfs_block_t *it;
+	int ret;
+
+	while (queue != NULL) {
+		it = queue;
+		queue = queue->next;
+
+		if (it->flags & SQFS_BLK_COMPRESS_ERROR) {
+			proc->status = SQFS_ERROR_COMRPESSOR;
+		} else {
+			ret = proc->cb(proc->user, it);
+			if (ret)
+				proc->status = ret;
+		}
+
+		free(it);
+	}
+
+	return proc->status;
+}
+
+int sqfs_block_processor_enqueue(sqfs_block_processor_t *proc,
+				 sqfs_block_t *block)
+{
+	sqfs_block_t *queue = NULL, *it, *prev;
+
+	block->sequence_number = proc->enqueue_id++;
+	block->next = NULL;
+
+	pthread_mutex_lock(&proc->mtx);
+	if ((block->flags & SQFS_BLK_DONT_COMPRESS) &&
+	    (block->flags & SQFS_BLK_DONT_CHECKSUM)) {
+		store_completed_block(proc, block);
+	} else {
+		while (proc->backlog > proc->max_backlog)
+			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 sqfs_block_processor_finish(sqfs_block_processor_t *proc)
+{
+	sqfs_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);
+
+			/* XXX: this would actually be a BUG */
+			return SQFS_ERROR_INTERNAL;
+		}
+	}
+
+	queue = proc->done;
+	proc->done = NULL;
+	pthread_mutex_unlock(&proc->mtx);
+
+	return process_completed_blocks(proc, queue);
+}