Refactor out common code of the block processors

Code that already is shared between the pthread and the serial
processor as well as code that can be re-used by other threading
API implementations.

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

7 files changed, 208 insertions, 185 deletions

diff --git a/lib/sqfs/Makemodule.am b/lib/sqfs/Makemodule.am
index 28f5a93..7a02fa4 100644
--- a/lib/sqfs/Makemodule.am
+++ b/lib/sqfs/Makemodule.am
@@ -21,6 +21,7 @@ libsquashfs_la_SOURCES += lib/sqfs/inode.c lib/sqfs/blk_proc/fragtbl.c
 libsquashfs_la_SOURCES += lib/sqfs/blk_proc/process_block.c lib/sqfs/io.c
 libsquashfs_la_SOURCES += lib/sqfs/blk_proc/internal.h lib/sqfs/data_reader.c
 libsquashfs_la_SOURCES += lib/sqfs/blk_proc/deduplicate.c
+libsquashfs_la_SOURCES += lib/sqfs/blk_proc/common.c
 libsquashfs_la_CPPFLAGS = $(AM_CPPFLAGS)
 libsquashfs_la_CFLAGS = $(AM_CFLAGS) $(PTHREAD_CFLAGS) $(ZLIB_CFLAGS)
 libsquashfs_la_CFLAGS += $(XZ_CFLAGS) $(LZO_CFLAGS) $(LZ4_CFLAGS)
diff --git a/lib/sqfs/blk_proc/common.c b/lib/sqfs/blk_proc/common.c
new file mode 100644
index 0000000..a3c91eb
--- /dev/null
+++ b/lib/sqfs/blk_proc/common.c
@@ -0,0 +1,158 @@
+/* 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 block_processor_init(sqfs_block_processor_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 block_processor_cleanup(sqfs_block_processor_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 block_processor_store_done(sqfs_block_processor_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 *block_processor_next_work_item(sqfs_block_processor_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 block_processor_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_block_processor_write_fragment_table(sqfs_block_processor_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/blk_proc/fragtbl.c b/lib/sqfs/blk_proc/fragtbl.c
index 84f5ed6..c8a3397 100644
--- a/lib/sqfs/blk_proc/fragtbl.c
+++ b/lib/sqfs/blk_proc/fragtbl.c
@@ -7,34 +7,6 @@
 #define SQFS_BUILDING_DLL
 #include "internal.h"
 
-int sqfs_block_processor_write_fragment_table(sqfs_block_processor_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;
-}
-
 static int grow_fragment_table(sqfs_block_processor_t *proc)
 {
 	size_t newsz;
diff --git a/lib/sqfs/blk_proc/internal.h b/lib/sqfs/blk_proc/internal.h
index 2e9980b..5fdbc3e 100644
--- a/lib/sqfs/blk_proc/internal.h
+++ b/lib/sqfs/blk_proc/internal.h
@@ -64,7 +64,6 @@ struct sqfs_block_processor_t {
 	sqfs_block_t *queue_last;
 
 	sqfs_block_t *done;
-	bool terminate;
 	size_t backlog;
 	int status;
 
@@ -105,10 +104,6 @@ struct sqfs_block_processor_t {
 #endif
 };
 
-SQFS_INTERNAL
-int sqfs_block_process(sqfs_block_t *block, sqfs_compressor_t *cmp,
-		       uint8_t *scratch, size_t scratch_size);
-
 SQFS_INTERNAL int process_completed_block(sqfs_block_processor_t *proc,
 					  sqfs_block_t *block);
 
@@ -123,4 +118,25 @@ SQFS_INTERNAL int store_block_location(sqfs_block_processor_t *proc,
 				       uint64_t offset, uint32_t size,
 				       uint32_t chksum);
 
+SQFS_INTERNAL void free_blk_list(sqfs_block_t *list);
+
+SQFS_INTERNAL
+int block_processor_init(sqfs_block_processor_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 block_processor_cleanup(sqfs_block_processor_t *proc);
+
+SQFS_INTERNAL
+void block_processor_store_done(sqfs_block_processor_t *proc,
+				sqfs_block_t *blk, int status);
+
+SQFS_INTERNAL
+sqfs_block_t *block_processor_next_work_item(sqfs_block_processor_t *proc);
+
+SQFS_INTERNAL
+int block_processor_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/blk_proc/process_block.c b/lib/sqfs/blk_proc/process_block.c
index f154a14..2951406 100644
--- a/lib/sqfs/blk_proc/process_block.c
+++ b/lib/sqfs/blk_proc/process_block.c
@@ -9,37 +9,6 @@
 
 #include <string.h>
 
-int sqfs_block_process(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;
-}
-
 static int allign_file(sqfs_block_processor_t *proc, sqfs_block_t *blk)
 {
 	if (!(blk->flags & SQFS_BLK_ALLIGN))
diff --git a/lib/sqfs/blk_proc/pthread.c b/lib/sqfs/blk_proc/pthread.c
index 1c1088a..57b61c1 100644
--- a/lib/sqfs/blk_proc/pthread.c
+++ b/lib/sqfs/blk_proc/pthread.c
@@ -7,65 +7,6 @@
 #define SQFS_BUILDING_DLL
 #include "internal.h"
 
-static void free_blk_list(sqfs_block_t *list)
-{
-	sqfs_block_t *it;
-
-	while (list != NULL) {
-		it = list;
-		list = list->next;
-		free(it);
-	}
-}
-
-static void store_completed_block(sqfs_block_processor_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;
-	pthread_cond_broadcast(&proc->done_cond);
-}
-
-static sqfs_block_t *get_next_work_item(sqfs_block_processor_t *proc)
-{
-	sqfs_block_t *blk;
-
-	while (proc->queue == NULL) {
-		if (proc->terminate || proc->status != 0)
-			return NULL;
-
-		pthread_cond_wait(&proc->queue_cond, &proc->mtx);
-	}
-
-	blk = proc->queue;
-	proc->queue = blk->next;
-	blk->next = NULL;
-
-	if (proc->queue == NULL)
-		proc->queue_last = NULL;
-
-	return blk;
-}
-
 static void *worker_proc(void *arg)
 {
 	compress_worker_t *worker = arg;
@@ -75,17 +16,23 @@ static void *worker_proc(void *arg)
 
 	for (;;) {
 		pthread_mutex_lock(&shared->mtx);
-		if (blk != NULL)
-			store_completed_block(shared, blk, status);
+		if (blk != NULL) {
+			block_processor_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 = get_next_work_item(shared);
+		blk = block_processor_next_work_item(shared);
 		pthread_mutex_unlock(&shared->mtx);
 
 		if (blk == NULL)
 			break;
 
-		status = sqfs_block_process(blk, worker->cmp, worker->scratch,
-					    shared->max_block_size);
+		status = block_processor_do_block(blk, worker->cmp,
+						  worker->scratch,
+						  shared->max_block_size);
 	}
 	return NULL;
 }
@@ -109,26 +56,14 @@ sqfs_block_processor_t *sqfs_block_processor_create(size_t max_block_size,
 	if (proc == NULL)
 		return NULL;
 
-	proc->max_block_size = max_block_size;
-	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;
-	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)
-		goto fail_init;
 
-	proc->frag_list = alloc_array(sizeof(proc->frag_list[0]),
-				      proc->frag_list_max);
-	if (proc->frag_list == NULL)
+	if (block_processor_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),
@@ -155,7 +90,7 @@ sqfs_block_processor_t *sqfs_block_processor_create(size_t max_block_size,
 	return proc;
 fail_thread:
 	pthread_mutex_lock(&proc->mtx);
-	proc->terminate = true;
+	proc->status = -1;
 	pthread_cond_broadcast(&proc->queue_cond);
 	pthread_mutex_unlock(&proc->mtx);
 
@@ -178,10 +113,7 @@ fail_init:
 	pthread_cond_destroy(&proc->done_cond);
 	pthread_cond_destroy(&proc->queue_cond);
 	pthread_mutex_destroy(&proc->mtx);
-	free(proc->frag_list);
-	free(proc->fragments);
-	free(proc->blocks);
-	free(proc);
+	block_processor_cleanup(proc);
 	return NULL;
 }
 
@@ -190,7 +122,7 @@ void sqfs_block_processor_destroy(sqfs_block_processor_t *proc)
 	unsigned int i;
 
 	pthread_mutex_lock(&proc->mtx);
-	proc->terminate = true;
+	proc->status = -1;
 	pthread_cond_broadcast(&proc->queue_cond);
 	pthread_mutex_unlock(&proc->mtx);
 
@@ -205,13 +137,7 @@ void sqfs_block_processor_destroy(sqfs_block_processor_t *proc)
 	pthread_cond_destroy(&proc->queue_cond);
 	pthread_mutex_destroy(&proc->mtx);
 
-	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);
+	block_processor_cleanup(proc);
 }
 
 static void append_to_work_queue(sqfs_block_processor_t *proc,
diff --git a/lib/sqfs/blk_proc/serial.c b/lib/sqfs/blk_proc/serial.c
index c7ec366..67272a3 100644
--- a/lib/sqfs/blk_proc/serial.c
+++ b/lib/sqfs/blk_proc/serial.c
@@ -15,32 +15,15 @@ sqfs_block_processor_t *sqfs_block_processor_create(size_t max_block_size,
 						    sqfs_file_t *file)
 {
 	sqfs_block_processor_t *proc;
-	(void)num_workers;
-	(void)max_backlog;
 
 	proc = alloc_flex(sizeof(*proc), 1, max_block_size);
 
 	if (proc == NULL)
 		return NULL;
 
-	proc->max_block_size = max_block_size;
-	proc->cmp = cmp;
-	proc->devblksz = devblksz;
-	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) {
-		free(proc);
-		return NULL;
-	}
-
-	proc->frag_list = alloc_array(sizeof(proc->frag_list[0]),
-				      proc->frag_list_max);
-	if (proc->frag_list == NULL) {
-		free(proc->blocks);
-		free(proc);
+	if (block_processor_init(proc, max_block_size, cmp, num_workers,
+				 max_backlog, devblksz, file)) {
+		block_processor_cleanup(proc);
 		return NULL;
 	}
 
@@ -49,11 +32,7 @@ sqfs_block_processor_t *sqfs_block_processor_create(size_t max_block_size,
 
 void sqfs_block_processor_destroy(sqfs_block_processor_t *proc)
 {
-	free(proc->frag_block);
-	free(proc->frag_list);
-	free(proc->fragments);
-	free(proc->blocks);
-	free(proc);
+	block_processor_cleanup(proc);
 }
 
 int sqfs_block_processor_enqueue(sqfs_block_processor_t *proc,
@@ -89,8 +68,9 @@ int sqfs_block_processor_enqueue(sqfs_block_processor_t *proc,
 		block = fragblk;
 	}
 
-	proc->status = sqfs_block_process(block, proc->cmp, proc->scratch,
-					  proc->max_block_size);
+	proc->status = block_processor_do_block(block, proc->cmp,
+						proc->scratch,
+						proc->max_block_size);
 
 	if (proc->status == 0)
 		proc->status = process_completed_block(proc, block);
@@ -104,8 +84,9 @@ int sqfs_block_processor_finish(sqfs_block_processor_t *proc)
 	if (proc->status != 0 || proc->frag_block == NULL)
 		return proc->status;
 
-	proc->status = sqfs_block_process(proc->frag_block, proc->cmp,
-					  proc->scratch, proc->max_block_size);
+	proc->status = block_processor_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);