Expose SerdByteSink in public API

2 files changed, 104 insertions, 5 deletions

diff --git a/src/byte_sink.c b/src/byte_sink.c
new file mode 100644
index 00000000..738290fa
--- /dev/null
+++ b/src/byte_sink.c
@@ -0,0 +1,100 @@
+/*
+  Copyright 2011-2020 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "serd_internal.h"
+#include "system.h"
+
+#include "serd/serd.h"
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct SerdByteSinkImpl {
+	SerdWriteFunc sink;
+	void*         stream;
+	char*         buf;
+	size_t        size;
+	size_t        block_size;
+};
+
+SerdByteSink*
+serd_byte_sink_new(SerdWriteFunc write_func, void* stream, size_t block_size)
+{
+	SerdByteSink* sink = (SerdByteSink*)calloc(1, sizeof(SerdByteSink));
+
+	sink->sink       = write_func;
+	sink->stream     = stream;
+	sink->block_size = block_size;
+	sink->buf = ((block_size > 1) ? (char*)serd_bufalloc(block_size) : NULL);
+	return sink;
+}
+
+size_t
+serd_byte_sink_write(const void*   buf,
+                     size_t        size,
+                     size_t        nmemb,
+                     SerdByteSink* sink)
+{
+	assert(size == 1);
+	(void)size;
+
+	if (nmemb == 0) {
+		return 0;
+	} else if (sink->block_size == 1) {
+		return sink->sink(buf, 1, nmemb, sink->stream);
+	}
+
+	const size_t orig_len = nmemb;
+	while (nmemb) {
+		const size_t space = sink->block_size - sink->size;
+		const size_t n     = MIN(space, nmemb);
+
+		// Write as much as possible into the remaining buffer space
+		memcpy(sink->buf + sink->size, buf, n);
+		sink->size += n;
+		buf = (const char*)buf + n;
+		nmemb -= n;
+
+		// Flush page if buffer is full
+		if (sink->size == sink->block_size) {
+			sink->sink(sink->buf, 1, sink->block_size, sink->stream);
+			sink->size = 0;
+		}
+	}
+
+	return orig_len;
+}
+
+void
+serd_byte_sink_flush(SerdByteSink* sink)
+{
+	if (sink->block_size > 1 && sink->size > 0) {
+		sink->sink(sink->buf, 1, sink->size, sink->stream);
+		sink->size = 0;
+	}
+}
+
+void
+serd_byte_sink_free(SerdByteSink* sink)
+{
+	if (sink) {
+		serd_byte_sink_flush(sink);
+		free(sink->buf);
+		free(sink);
+	}
+}
diff --git a/src/writer.c b/src/writer.c
index 3e918a0c..8e0a5c04 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -14,7 +14,6 @@
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
-#include "byte_sink.h"
 #include "env.h"
 #include "node.h"
 #include "serd_internal.h"
@@ -95,7 +94,7 @@ struct SerdWriterImpl {
 	SerdNode*      root_node;
 	SerdURI        root_uri;
 	SerdStack      anon_stack;
-	SerdByteSink   byte_sink;
+	SerdByteSink*  byte_sink;
 	SerdErrorSink  error_sink;
 	void*          error_handle;
 	WriteContext   context;
@@ -156,7 +155,7 @@ ctx(SerdWriter* writer, const SerdField field)
 static inline size_t
 sink(const void* buf, size_t len, SerdWriter* writer)
 {
-	return serd_byte_sink_write(buf, len, &writer->byte_sink);
+	return serd_byte_sink_write(buf, 1, len, writer->byte_sink);
 }
 
 // Write a single character, as an escape for single byte characters
@@ -860,7 +859,7 @@ serd_writer_finish(SerdWriter* writer)
 	if (ctx(writer, SERD_GRAPH)) {
 		write_sep(writer, SEP_GRAPH_END);
 	}
-	serd_byte_sink_flush(&writer->byte_sink);
+	serd_byte_sink_flush(writer->byte_sink);
 	free_context(writer);
 	writer->indent  = 0;
 	writer->context = WRITE_CONTEXT_NULL;
@@ -981,7 +980,7 @@ serd_writer_free(SerdWriter* writer)
 	serd_writer_finish(writer);
 	serd_stack_free(&writer->anon_stack);
 	free(writer->bprefix);
-	serd_byte_sink_free(&writer->byte_sink);
+	serd_byte_sink_free(writer->byte_sink);
 	serd_node_free(writer->root_node);
 	free(writer);
 }