Implement a data writer based output stream

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

1 files changed, 91 insertions, 0 deletions

diff --git a/lib/common/data_writer_ostream.c b/lib/common/data_writer_ostream.c
new file mode 100644
index 0000000..94a04f2
--- /dev/null
+++ b/lib/common/data_writer_ostream.c
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * data_writer_ostream.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "common.h"
+
+#include <stdlib.h>
+
+typedef struct{
+	ostream_t base;
+
+	sqfs_block_processor_t *proc;
+	const char *filename;
+} data_writer_ostream_t;
+
+static int stream_append(ostream_t *base, const void *data, size_t size)
+{
+	data_writer_ostream_t *strm = (data_writer_ostream_t *)base;
+	int ret;
+
+	ret = sqfs_block_processor_append(strm->proc, data, size);
+
+	if (ret != 0) {
+		sqfs_perror(strm->filename, NULL, ret);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int stream_flush(ostream_t *base)
+{
+	data_writer_ostream_t *strm = (data_writer_ostream_t *)base;
+	int ret;
+
+	ret = sqfs_block_processor_end_file(strm->proc);
+
+	if (ret != 0) {
+		sqfs_perror(strm->filename, NULL, ret);
+		return -1;
+	}
+
+	return 0;
+}
+
+static const char *stream_get_filename(ostream_t *base)
+{
+	data_writer_ostream_t *strm = (data_writer_ostream_t *)base;
+
+	return strm->filename;
+}
+
+static void stream_destroy(sqfs_object_t *base)
+{
+	free(base);
+}
+
+ostream_t *data_writer_ostream_create(const char *filename,
+				      sqfs_block_processor_t *proc,
+				      sqfs_inode_generic_t **inode,
+				      int flags)
+{
+	data_writer_ostream_t *strm = calloc(1, sizeof(*strm));
+	sqfs_object_t *obj = (sqfs_object_t *)strm;
+	ostream_t *base = (ostream_t *)strm;
+	int ret;
+
+	if (strm == NULL) {
+		perror(filename);
+		return NULL;
+	}
+
+	ret = sqfs_block_processor_begin_file(proc, inode, NULL, flags);
+
+	if (ret != 0) {
+		sqfs_perror(filename, NULL, ret);
+		free(strm);
+		return NULL;
+	}
+
+	strm->proc = proc;
+	strm->filename = filename;
+	base->append = stream_append;
+	base->flush = stream_flush;
+	base->get_filename = stream_get_filename;
+	obj->destroy = stream_destroy;
+	return base;
+}