Add a first approximation of a lookup algorithm

This isn't really "correct" but it's probably going to work. It's
a rough implementation of the Kademlia lookup algorithm, with the
modification that we don't keep track of anything behind the frontier.
We are therefore counting on peers being ok with us potentially sending
them the "same" request multiple times. If they respond in a reasonable
time, the double request rate _should_ be minimal, but that of course
carries the risk that an already overloaded peer would get even more
queries.

I don't know. It's a first try at something. I need to see it work
before I write it off completely.

1 files changed, 14 insertions, 26 deletions

diff --git a/src/main.c b/src/main.c
index a18cb78..267f324 100644
--- a/src/main.c
+++ b/src/main.c
@@ -129,18 +129,6 @@ void flush_messages(int sfd, struct message* cursor, const struct message* const
 	}
 }
 
-struct lookup {
-	struct nodeid target;
-
-	struct nodeid closest[8];
-	struct addr closest_addr[8];
-	bool closest_valid[8]; // @SLOP: This could be a single word
-
-	uint64_t outstanding;
-
-	time_t wake;
-};
-
 #define OUTBOX_SIZE 32
 int main(int argc, char** argv) {
 	srand(time(NULL));
@@ -183,20 +171,20 @@ int main(int argc, char** argv) {
 	proto_begin(&dht, time(NULL), &message_cursor, outbuff+32);
 	flush_messages(dht.sfd, outbuff, message_cursor);
 
-	/* struct lookup lookup; */
-	/* // Init the lookup */
-	/* { */
-	/* 	lookup.wake = 0; */
-	/* 	lookup.target = (struct nodeid){.inner={0x19b8a941, 0x38fa0191, 0x1403fac2, 0x581000ab, 0x19583cda}}; */
-
-	/* 	struct entry* entry[8]; */
-	/* 	int found = routing_closest(&lookup.target, 8, entry); */
-	/* 	for(size_t i = 0; i < found; i++) { */
-	/* 		lookup.closest[i] = entry[i]->id; */
-	/* 		lookup.closest_addr[i] = entry[i]->addr; */
-	/* 		lookup.closest_valid[i] = true; */
-	/* 	} */
-	/* } */
+	// Init the lookup
+	struct lookup *lookup = &dht.lookup;
+	{
+		lookup->timeout = 0;
+		lookup->target = (struct nodeid){.inner={0x19b8a941, 0x38fa0191, 0x1403fac2, 0x581000ab, 0x19583cda}};
+
+		struct entry* entry[8];
+		int found = routing_closest(&lookup->target, sizeof(entry)/sizeof(entry[0]), entry);
+		assert(found == 8);
+		for(size_t i = 0; i < found; i++) {
+			lookup->closest[i] = entry[i]->id;
+			lookup->closest_addr[i] = entry[i]->addr;
+		}
+	}
 
 #define RECV_BUFF_SIZE 4096
 	char buff_storage[RECV_BUFF_SIZE+1];