1 files changed, 55 insertions, 0 deletions
diff --git a/lib/common/data_writer.c b/lib/common/data_writer.c
new file mode 100644
index 0000000..36de154
--- /dev/null
+++ b/lib/common/data_writer.c
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * data_writer.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "common.h"
+#include "util.h"
+
+static sqfs_u8 buffer[4096];
+
+int write_data_from_file(const char *filename, sqfs_data_writer_t *data,
+			 sqfs_inode_generic_t *inode, sqfs_file_t *file,
+			 int flags)
+{
+	sqfs_u64 filesz, offset;
+	size_t diff;
+	int ret;
+
+	ret = sqfs_data_writer_begin_file(data, inode, flags);
+	if (ret) {
+		sqfs_perror(filename, "beginning file data blocks", ret);
+		return -1;
+	}
+
+	sqfs_inode_get_file_size(inode, &filesz);
+
+	for (offset = 0; offset < filesz; offset += diff) {
+		if (filesz - offset > sizeof(buffer)) {
+			diff = sizeof(buffer);
+		} else {
+			diff = filesz - offset;
+		}
+
+		ret = file->read_at(file, offset, buffer, diff);
+		if (ret) {
+			sqfs_perror(filename, "reading file range", ret);
+			return -1;
+		}
+
+		ret = sqfs_data_writer_append(data, buffer, diff);
+		if (ret) {
+			sqfs_perror(filename, "packing file data", ret);
+			return -1;
+		}
+	}
+
+	ret = sqfs_data_writer_end_file(data);
+	if (ret) {
+		sqfs_perror(filename, "finishing file data", ret);
+		return -1;
+	}
+
+	return 0;
+}