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29
30 // Pool of Client instances, implemented with LRUCache.
31
32 #include "unix/emacs/client_pool.h"
33
34 namespace mozc {
35 namespace emacs {
36
37 static const int kMaxClients = 64; // max number of parallel clients
38
ClientPool()39 ClientPool::ClientPool() : lru_cache_(kMaxClients), next_id_(1) {
40 }
41
CreateClient()42 int ClientPool::CreateClient() {
43 // Emacs supports at-least 28-bit integer.
44 const int k28BitIntMax = 134217727;
45 while (lru_cache_.HasKey(next_id_)) {
46 if (++next_id_ <= 0 || k28BitIntMax < next_id_) {
47 next_id_ = 1; // Keep next_id_ to be a positive 28-bit integer.
48 }
49 }
50 lru_cache_.Insert(next_id_, std::make_shared<Client>());
51 return next_id_++;
52 }
53
DeleteClient(int id)54 void ClientPool::DeleteClient(int id) {
55 lru_cache_.Erase(id);
56 }
57
GetClient(int id)58 std::shared_ptr<ClientPool::Client> ClientPool::GetClient(int id) {
59 const std::shared_ptr<Client> *value = lru_cache_.Lookup(id);
60 if (value) {
61 lru_cache_.Insert(id, *value); // Put id at the head of LRU.
62 return *value;
63 } else {
64 std::shared_ptr<Client> client_ptr = std::make_shared<Client>();
65 lru_cache_.Insert(id, client_ptr);
66 return client_ptr;
67 }
68 }
69
70 } // namespace emacs
71 } // namespace mozc
72