1 files changed, 74 insertions, 0 deletions
diff --git a/server/query.c b/server/query.c
new file mode 100644
index 0000000..16f48b6
--- /dev/null
+++ b/server/query.c
@@ -0,0 +1,74 @@
+/*
+ * server/query.c
+ */
+
+
+#include <arpa/inet.h>
+#include <inttypes.h>
+#include <byteswap.h>
+#include <syslog.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include "dnbd2.h"
+#include "query.h"
+#include "tree.h"
+#include "file.h"
+
+
+int handle_query(dnbd2_data_request_t *request,
+		 dnbd2_data_reply_t *reply,
+		 void **tree)
+{
+	int fd, i;
+	node_t node1;
+	node_t *node2;
+	dataset_t ds;
+	off_t size, pos;
+	uint16_t cmd;
+
+	/* Fetch the right fd for this vid/rid pair. */
+	ds.vid = ntohs(request->vid);
+	ds.rid = ntohs(request->rid);
+	node1.ds = &ds;
+	node2 = tree_find(&node1, tree);
+	if (!node2)
+		return -1;
+	fd = node2->fd;
+
+	cmd = ntohs(request->cmd);
+	switch (cmd) {
+	case CMD_GET_BLOCK:
+		reply->num = request->num;
+		pos = ntohll(request->num);
+		file_read(fd, reply->payload.data, DNBD2_BLOCK_SIZE, pos);
+		break;
+
+	case CMD_GET_SIZE:
+		if (file_getsize(fd, &size) == -1)
+			return -1;
+		reply->num  = htonll(size);
+		break;
+
+	case CMD_GET_SERVERS:
+		/* Fetch a random block to deliver a more realistic RTT. */
+		pos = 0;
+		if (!file_getsize(fd, &size))
+			pos = (off_t) (size * (rand() / (RAND_MAX + 1.0)));
+		file_read(fd, reply->payload.data, DNBD2_BLOCK_SIZE, pos);
+		reply->num = htonll(node2->servers);
+		for (i=0 ; i<node2->servers ; i++) {
+			memcpy(&reply->payload.server[i],
+			       &node2->server[i],
+			       sizeof(dnbd2_server_t));
+		}
+		break;
+	}
+
+	reply->cmd  = request->cmd;
+	reply->time = request->time;
+	reply->vid  = request->vid;
+	reply->rid  = request->rid;
+
+	return 0;
+}