1 files changed, 128 insertions, 0 deletions
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;
+}