1 files changed, 79 insertions, 0 deletions
diff --git a/server/zbuffer.c b/server/zbuffer.c
new file mode 100644
index 0000000..af37f74
--- /dev/null
+++ b/server/zbuffer.c
@@ -0,0 +1,79 @@
+#include <assert.h>
+#include <zlib.h>
+#include "zbuffer.h"
+
+#define BUFSZ_ZOUT (256*1024)
+
+
+struct zbuffer {
+	u8 *out;
+	i64 outfill;
+	z_stream strm;
+
+	zbuffer_writefunc *wf;
+	void *payload;
+};
+
+struct zbuffer* zbuffer_init(zbuffer_writefunc *wf,void *payload){
+	struct zbuffer *z=malloc(1,struct zbuffer);
+	z->out=malloc(BUFSZ_ZOUT,u8);
+	z->outfill=0;
+
+	z->strm.zalloc=Z_NULL;
+	z->strm.zfree=Z_NULL;
+	z->strm.opaque=Z_NULL;
+
+	// so zbuffer_write can start writing immediately
+	z->strm.avail_out=BUFSZ_ZOUT;
+	z->strm.next_out=z->out;
+
+	if(deflateInit(&z->strm,Z_DEFAULT_COMPRESSION)!=Z_OK){
+		return NULL;
+	}
+
+	z->wf=wf;
+	z->payload=payload;
+	return z;
+}
+
+void zbuffer_write(struct zbuffer *z,u8 *data,i64 len){
+	z->strm.avail_in=len;
+	z->strm.next_in=data;
+	assert(z->strm.avail_out>0);
+	while(true){
+		int ret=deflate(&z->strm,Z_NO_FLUSH);
+		assert(ret==Z_OK);
+		if(z->strm.avail_out>0)break;
+		z->wf(z->out,BUFSZ_ZOUT,z->payload);
+		z->strm.avail_out=BUFSZ_ZOUT;
+		z->strm.next_out=z->out;
+	}
+	assert(z->strm.avail_in==0);
+}
+
+void zbuffer_flush(struct zbuffer *z){
+	assert(z->strm.avail_out>0);
+	while(true){
+		int ret=deflate(&z->strm,Z_SYNC_FLUSH);
+		assert(ret==Z_OK);
+		z->wf(z->out,BUFSZ_ZOUT-z->strm.avail_out,z->payload);
+		bool done=z->strm.avail_out>0;
+		z->strm.avail_out=BUFSZ_ZOUT;
+		z->strm.next_out=z->out;
+		if(done)break;
+	}
+}
+
+void zbuffer_finish_destroy(struct zbuffer *z){
+	assert(z->strm.avail_out>0);
+	while(true){
+		int ret=deflate(&z->strm,Z_FINISH);
+		assert(ret==Z_OK||ret==Z_STREAM_END);
+		z->wf(z->out,BUFSZ_ZOUT-z->strm.avail_out,z->payload);
+		if(z->strm.avail_out>0)break;
+		z->strm.avail_out=BUFSZ_ZOUT;
+		z->strm.next_out=z->out;
+	}
+	free(z->out);
+	free(z);
+}