Cleanup the block processor file structure

A cleaner separation between common code, frontend code and backend
code is made.

The "is this byte blob zero" function is moved out to libutil (with
test case and everything) with a more optimized implementation.

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

1 files changed, 41 insertions, 213 deletions

diff --git a/lib/sqfs/block_processor/frontend.c b/lib/sqfs/block_processor/frontend.c
index 8bd6cf2..ccf54c0 100644
--- a/lib/sqfs/block_processor/frontend.c
+++ b/lib/sqfs/block_processor/frontend.c
@@ -7,123 +7,46 @@
 #define SQFS_BUILDING_DLL
 #include "internal.h"
 
-static sqfs_block_t *get_new_block(sqfs_block_processor_t *proc)
+static int get_new_block(sqfs_block_processor_t *proc, sqfs_block_t **out)
 {
 	sqfs_block_t *blk;
 
+	while (proc->backlog >= proc->max_backlog) {
+		int ret = dequeue_block(proc);
+		if (ret != 0)
+			return ret;
+	}
+
 	if (proc->free_list != NULL) {
 		blk = proc->free_list;
 		proc->free_list = blk->next;
 	} else {
 		blk = malloc(sizeof(*blk) + proc->max_block_size);
+		if (blk == NULL)
+			return SQFS_ERROR_ALLOC;
 	}
 
-	if (blk != NULL)
-		memset(blk, 0, sizeof(*blk));
-
-	return blk;
+	memset(blk, 0, sizeof(*blk));
+	*out = blk;
+	return 0;
 }
 
-static int dequeue_block(sqfs_block_processor_t *proc)
+static int add_sentinel_block(sqfs_block_processor_t *proc)
 {
-	sqfs_block_t *blk, *fragblk, *it, *prev;
-	bool have_dequeued = false;
-	int status;
-retry:
-	while (proc->io_queue != NULL) {
-		if (proc->io_queue->io_seq_num != proc->io_deq_seq_num)
-			break;
-
-		blk = proc->io_queue;
-		proc->io_queue = blk->next;
-		proc->io_deq_seq_num += 1;
-		proc->backlog -= 1;
-		have_dequeued = true;
-
-		status = process_completed_block(proc, blk);
-		if (status != 0)
-			return status;
-	}
-
-	if (have_dequeued)
-		return 0;
-
-	blk = proc->pool->dequeue(proc->pool);
-
-	if (blk == NULL) {
-		status = proc->pool->get_status(proc->pool);
-		if (status == 0)
-			status = SQFS_ERROR_INTERNAL;
-
-		return status;
-	}
-
-	proc->backlog -= 1;
-	have_dequeued = true;
-
-	if (blk->flags & SQFS_BLK_IS_FRAGMENT) {
-		fragblk = NULL;
-		status = process_completed_fragment(proc, blk, &fragblk);
-
-		if (status != 0) {
-			free(fragblk);
-			return status;
-		}
-
-		if (fragblk != NULL) {
-			fragblk->io_seq_num = proc->io_seq_num++;
-
-			if (proc->pool->submit(proc->pool, fragblk) != 0) {
-				free(fragblk);
-
-				if (status == 0) {
-					status = proc->pool->
-						get_status(proc->pool);
-
-					if (status == 0)
-						status = SQFS_ERROR_ALLOC;
-				}
-
-				return status;
-			}
-
-			proc->backlog += 1;
-			have_dequeued = false;
-		}
-	} else {
-		if (!(blk->flags & SQFS_BLK_FRAGMENT_BLOCK))
-			blk->io_seq_num = proc->io_seq_num++;
-
-		prev = NULL;
-		it = proc->io_queue;
-
-		while (it != NULL) {
-			if (it->io_seq_num >= blk->io_seq_num)
-				break;
-
-			prev = it;
-			it = it->next;
-		}
-
-		if (prev == NULL) {
-			blk->next = proc->io_queue;
-			proc->io_queue = blk;
-		} else {
-			blk->next = prev->next;
-			prev->next = blk;
-		}
+	sqfs_block_t *blk;
+	int ret;
 
-		proc->backlog += 1;
-		have_dequeued = false;
-	}
+	ret = get_new_block(proc, &blk);
+	if (ret != 0)
+		return ret;
 
-	if (!have_dequeued)
-		goto retry;
+	blk->inode = proc->inode;
+	blk->flags = proc->blk_flags | SQFS_BLK_LAST_BLOCK;
 
-	return 0;
+	return enqueue_block(proc, blk);
 }
 
-static int enqueue_block(sqfs_block_processor_t *proc, sqfs_block_t *blk)
+int enqueue_block(sqfs_block_processor_t *proc, sqfs_block_t *blk)
 {
 	int status;
 
@@ -141,44 +64,6 @@ static int enqueue_block(sqfs_block_processor_t *proc, sqfs_block_t *blk)
 	return 0;
 }
 
-static int add_sentinel_block(sqfs_block_processor_t *proc)
-{
-	sqfs_block_t *blk;
-	int ret;
-
-	if (proc->backlog == proc->max_backlog) {
-		ret = dequeue_block(proc);
-		if (ret != 0)
-			return ret;
-	}
-
-	blk = get_new_block(proc);
-	if (blk == NULL)
-		return SQFS_ERROR_ALLOC;
-
-	blk->inode = proc->inode;
-	blk->flags = proc->blk_flags | SQFS_BLK_LAST_BLOCK;
-
-	return enqueue_block(proc, blk);
-}
-
-static int flush_block(sqfs_block_processor_t *proc)
-{
-	sqfs_block_t *block;
-	int ret;
-
-	if (proc->backlog == proc->max_backlog) {
-		ret = dequeue_block(proc);
-		if (ret != 0)
-			return ret;
-	}
-
-	block = proc->blk_current;
-	proc->blk_current = NULL;
-
-	return enqueue_block(proc, block);
-}
-
 int sqfs_block_processor_begin_file(sqfs_block_processor_t *proc,
 				    sqfs_inode_generic_t **inode,
 				    void *user, sqfs_u32 flags)
@@ -224,9 +109,9 @@ int sqfs_block_processor_append(sqfs_block_processor_t *proc, const void *data,
 
 	while (size > 0) {
 		if (proc->blk_current == NULL) {
-			new = get_new_block(proc);
-			if (new == NULL)
-				return SQFS_ERROR_ALLOC;
+			err = get_new_block(proc, &new);
+			if (err != 0)
+				return err;
 
 			proc->blk_current = new;
 			proc->blk_current->flags = proc->blk_flags;
@@ -239,7 +124,9 @@ int sqfs_block_processor_append(sqfs_block_processor_t *proc, const void *data,
 		diff = proc->max_block_size - proc->blk_current->size;
 
 		if (diff == 0) {
-			err = flush_block(proc);
+			err = enqueue_block(proc, proc->blk_current);
+			proc->blk_current = NULL;
+
 			if (err)
 				return err;
 			continue;
@@ -258,9 +145,12 @@ int sqfs_block_processor_append(sqfs_block_processor_t *proc, const void *data,
 		proc->stats.input_bytes_read += diff;
 	}
 
-	if (proc->blk_current != NULL &&
-	    proc->blk_current->size == proc->max_block_size) {
-		return flush_block(proc);
+	if (proc->blk_current->size == proc->max_block_size) {
+		err = enqueue_block(proc, proc->blk_current);
+		proc->blk_current = NULL;
+
+		if (err)
+			return err;
 	}
 
 	return 0;
@@ -293,7 +183,9 @@ int sqfs_block_processor_end_file(sqfs_block_processor_t *proc)
 			proc->blk_current->flags |= SQFS_BLK_IS_FRAGMENT;
 		}
 
-		err = flush_block(proc);
+		err = enqueue_block(proc, proc->blk_current);
+		proc->blk_current = NULL;
+
 		if (err)
 			return err;
 	}
@@ -321,78 +213,14 @@ int sqfs_block_processor_submit_block(sqfs_block_processor_t *proc, void *user,
 	if (flags & ~SQFS_BLK_FLAGS_ALL)
 		return SQFS_ERROR_UNSUPPORTED;
 
-	if (proc->backlog == proc->max_backlog) {
-		ret = dequeue_block(proc);
-		if (ret != 0)
-			return ret;
-	}
-
-	blk = get_new_block(proc);
-	if (blk == NULL)
-		return SQFS_ERROR_ALLOC;
+	ret = get_new_block(proc, &blk);
+	if (ret != 0)
+		return ret;
 
 	blk->flags = flags | BLK_FLAG_MANUAL_SUBMISSION;
 	blk->user = user;
 	blk->size = size;
 	memcpy(blk->data, data, size);
 
-	ret = proc->pool->submit(proc->pool, blk);
-	if (ret != 0)
-		free(blk);
-
-	proc->backlog += 1;
-	return ret;
-}
-
-int sqfs_block_processor_sync(sqfs_block_processor_t *proc)
-{
-	int ret;
-
-	while (proc->backlog > 0) {
-		ret = dequeue_block(proc);
-		if (ret != 0)
-			return ret;
-	}
-
-	return 0;
-}
-
-int sqfs_block_processor_finish(sqfs_block_processor_t *proc)
-{
-	sqfs_block_t *blk;
-	int status;
-
-	status = sqfs_block_processor_sync(proc);
-	if (status != 0)
-		return status;
-
-	if (proc->frag_block != NULL) {
-		blk = proc->frag_block;
-		blk->next = NULL;
-		proc->frag_block = NULL;
-
-		blk->io_seq_num = proc->io_seq_num++;
-
-		status = proc->pool->submit(proc->pool, blk);
-		if (status != 0) {
-			status = proc->pool->get_status(proc->pool);
-
-			if (status == 0)
-				status = SQFS_ERROR_ALLOC;
-
-			free(blk);
-			return status;
-		}
-
-		proc->backlog += 1;
-		status = sqfs_block_processor_sync(proc);
-	}
-
-	return status;
-}
-
-const sqfs_block_processor_stats_t
-*sqfs_block_processor_get_stats(const sqfs_block_processor_t *proc)
-{
-	return &proc->stats;
+	return enqueue_block(proc, blk);
 }