[SERVER] Check which dnbd3 devices are idle and ready to use for proxy mode

[SERVER] Skeleton of server-to-server communication
[SERVER] Update access-time of images in use by actual clients
[*] Add dnbd3_host_t type to handle address+port+addrtype consistently across the project

1 files changed, 30 insertions, 0 deletions

diff --git a/src/server/helper.h b/src/server/helper.h
new file mode 100644
index 0000000..e787c42
--- /dev/null
+++ b/src/server/helper.h
@@ -0,0 +1,30 @@
+#ifndef HELPER_H_
+#define HELPER_H_
+
+#include "server.h"
+#include <netinet/in.h>
+#include <string.h>
+
+char parse_address(char *string, dnbd3_host_t *host);
+char host_to_string(const dnbd3_host_t *host, char *target, size_t targetlen);
+char is_valid_namespace(char *namespace);
+char is_valid_imagename(char *namespace);
+void strtolower(char *string);
+
+static inline int is_same_server(const dnbd3_trusted_server_t *const a, const dnbd3_trusted_server_t *const b)
+{
+	return (a->host.type == b->host.type)
+	       && (a->host.port == b->host.port)
+	       && (0 == memcmp(a->host.addr, b->host.addr, (a->host.type == AF_INET ? 4 : 16)));
+}
+
+// one byte in the map covers 8 4kib blocks, so 32kib per byte
+// "+ (1 << 15) - 1" is required to account for the last bit of
+// the image that is smaller than 32kib
+// this would be the case whenever the image file size is not a
+// multiple of 32kib (= the number of blocks is not divisible by 8)
+// ie: if the image is 49152 bytes and you do 49152 >> 15 you get 1,
+// but you actually need 2 bytes to have a complete cache map
+#define IMGSIZE_TO_MAPBYTES(bytes) ((int)(((bytes) + (1 << 15) - 1) >> 15))
+
+#endif