Add block processor data structure

The interface is designed for parallel, asynchronuous processing of data
blocks with an I/O callback that handles the serialized result.

The underlying implementation is currently still synchronuous.

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

1 files changed, 37 insertions, 0 deletions

diff --git a/lib/comp/process_block.c b/lib/comp/process_block.c
new file mode 100644
index 0000000..76cd07d
--- /dev/null
+++ b/lib/comp/process_block.c
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * process_block.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+
+#include "block_processor.h"
+#include "util.h"
+
+#include <string.h>
+
+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 = update_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;
+}