feat(cluster): check command keys ownership (#1194)

* feat(cluster): check command keys ownership on cluster mode

Signed-off-by: adi_holden <adi@dragonflydb.io>

src/server/cluster/cluster_config.cc

@@ -0,0 +1,53 @@
+extern "C" {
+#include "redis/crc16.h"
+}
+
+#include <shared_mutex>
+#include <string_view>
+
+#include "cluster_config.h"
+
+namespace dfly {
+
+bool ClusterConfig::cluster_enabled = false;
+
+static constexpr SlotId kMaxSlotNum = 0x3FFF;
+
+std::string_view ClusterConfig::KeyTag(std::string_view key) {
+  size_t start = key.find('{');
+  if (start == key.npos) {
+    return key;
+  }
+  size_t end = key.find('}', start + 1);
+  if (end == key.npos || end == start + 1) {
+    return key;
+  }
+  return key.substr(start + 1, end - start - 1);
+}
+
+SlotId ClusterConfig::KeySlot(std::string_view key) {
+  std::string_view tag = KeyTag(key);
+  return crc16(tag.data(), tag.length()) & kMaxSlotNum;
+}
+
+ClusterConfig::ClusterConfig() {
+  cluster_enabled = true;
+  AddSlots();
+}
+
+void ClusterConfig::AddSlots() {
+  // TODO update logic acording to config
+  // currently add all slots to owned slots
+  std::lock_guard lk{slots_mu_};
+  for (SlotId slot_id = 0; slot_id <= kMaxSlotNum; ++slot_id) {
+    owned_slots_.emplace(slot_id);
+  }
+  return;
+}
+
+bool ClusterConfig::IsMySlot(SlotId id) {
+  std::shared_lock sl(slots_mu_);
+  return owned_slots_.contains(id);
+}
+
+}  // namespace dfly