From decf51fab0196746bc740f168a0a4c254ee60a44 Mon Sep 17 00:00:00 2001
From: Ludovic 'Archivist' Lagouardette
 <archivist@172-0-0-153.lightspeed.brhmal.sbcglobal.net>
Date: Mon, 8 Jul 2019 13:55:41 +0200
Subject: [PATCH] Added the operation for sharding

---
 include/database.hpp  | 21 +++++++++++++++++++++
 include/network.hpp   |  7 ++++++-
 src/izaro-storage.cpp | 43 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/include/database.hpp b/include/database.hpp
index ce8dd1c..a3a79ca 100644
--- a/include/database.hpp
+++ b/include/database.hpp
@@ -1,6 +1,7 @@
 #pragma once
 #include "fsized_map.h"
 #include <chrono>
+#include <random>
 
 struct metadata_t{
 	bitops::regulated<uint64_t> record_cnt;
@@ -296,6 +297,26 @@ public:
 		return tmp.second;
 	}
 
+	record try_allocate(const record_identifier& target)
+	{
+		auto attempt = read(target);
+		if(attempt.first.timestamp == 0)
+		{
+			db_page rnd_page;
+			{
+				std::random_device dev;
+				std::minstd_rand temprng(dev());
+
+				auto tmp = (std::array<uint32_t, sizeof(db_page)/sizeof(uint32_t)>*)&rnd_page;
+				std::generate(tmp->begin(), tmp->end(), temprng);
+			}
+
+			return write(target, rnd_page);
+		}
+
+		return record{};
+	}
+
 	std::pair<record, db_page> stepped_read(const record_identifier& target) {
 		std::pair<record, db_page> ret;
 		ret.second.fill(0);
diff --git a/include/network.hpp b/include/network.hpp
index 972ebbb..eb2d280 100644
--- a/include/network.hpp
+++ b/include/network.hpp
@@ -8,7 +8,12 @@ enum class db_op : uint32_t {
 	read = 1,
 	write = 2,
 	remove = 3,
-	stats = 4
+	stats = 4,
+	sread = 5,
+	swrite = 6,
+	sallocate = 7,
+	sremove = 3,
+	confirm = 8
 };
 
 struct [[gnu::packed]] received_data {
diff --git a/src/izaro-storage.cpp b/src/izaro-storage.cpp
index 0b3cc62..484b53a 100644
--- a/src/izaro-storage.cpp
+++ b/src/izaro-storage.cpp
@@ -233,6 +233,7 @@ int main(
 						reply_size = sizeof(reply.rep_id) + sizeof(reply.identifier); 
 					}
 				break;
+				// case db_op::sremove:
 				case db_op::remove:
 					{
 						reply.rep_id = recv.rep_id;
@@ -264,6 +265,48 @@ int main(
 						reply_size = sizeof(reply);
 					}
 				break;
+				case db_op::sallocate:
+					{
+						reply.rep_id = recv.rep_id;
+						reply.identifier = run_db.try_allocate(recv.identifier);
+						reply_size = sizeof(reply.rep_id) + sizeof(reply.identifier);
+					}
+				break;
+				case db_op::sread:
+					{
+						reply.rep_id = recv.rep_id;
+						auto req = run_db.stepped_read(recv.identifier);
+						if(req.first.timestamp != 0)
+						{
+							reply.identifier = req.first;
+							reply.page = req.second;
+							reply_size = sizeof(reply);
+						}
+						else
+						{
+							reply_size = sizeof(reply.rep_id) + sizeof(reply.identifier);
+						}
+					}
+				break;
+				case db_op::swrite:
+					{
+						reply.rep_id = recv.rep_id;
+						try{
+							auto req = run_db.stepped_write(recv.identifier, recv.page);
+							reply.identifier = req;
+						} catch (...) {
+							std::cerr << "cluster overfull"<< std::endl;
+						}
+						reply_size = sizeof(reply.rep_id) + sizeof(reply.identifier); 
+					}
+				break;
+				case db_op::confirm:
+					{
+						reply.rep_id = recv.rep_id;
+						run_db.confirm(recv.identifier, *(bitops::regulated<uint64_t>*)&recv.page);
+						reply_size = sizeof(reply.rep_id);
+					}
+				break;
 				default:
 					std::cerr << "bad_request " << (uint32_t)static_cast<db_op>(recv.op)  << std::endl;
 					continue;