10b57cec5SDimitry Andric //===-- UserIDResolver.h ----------------------------------------*- C++ -*-===// 20b57cec5SDimitry Andric // 30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 60b57cec5SDimitry Andric // 70b57cec5SDimitry Andric //===----------------------------------------------------------------------===// 80b57cec5SDimitry Andric 90b57cec5SDimitry Andric #ifndef LLDB_UTILITY_USERIDRESOLVER_H 100b57cec5SDimitry Andric #define LLDB_UTILITY_USERIDRESOLVER_H 110b57cec5SDimitry Andric 120b57cec5SDimitry Andric #include "llvm/ADT/DenseMap.h" 130b57cec5SDimitry Andric #include "llvm/ADT/StringRef.h" 140b57cec5SDimitry Andric #include <mutex> 15bdd1243dSDimitry Andric #include <optional> 160b57cec5SDimitry Andric 170b57cec5SDimitry Andric namespace lldb_private { 180b57cec5SDimitry Andric 190b57cec5SDimitry Andric /// An abstract interface for things that know how to map numeric user/group IDs 200b57cec5SDimitry Andric /// into names. It caches the resolved names to avoid repeating expensive 210b57cec5SDimitry Andric /// queries. The cache is internally protected by a mutex, so concurrent queries 220b57cec5SDimitry Andric /// are safe. 230b57cec5SDimitry Andric class UserIDResolver { 240b57cec5SDimitry Andric public: 250b57cec5SDimitry Andric typedef uint32_t id_t; 260b57cec5SDimitry Andric virtual ~UserIDResolver(); // anchor 270b57cec5SDimitry Andric GetUserName(id_t uid)28bdd1243dSDimitry Andric std::optional<llvm::StringRef> GetUserName(id_t uid) { 290b57cec5SDimitry Andric return Get(uid, m_uid_cache, &UserIDResolver::DoGetUserName); 300b57cec5SDimitry Andric } GetGroupName(id_t gid)31bdd1243dSDimitry Andric std::optional<llvm::StringRef> GetGroupName(id_t gid) { 320b57cec5SDimitry Andric return Get(gid, m_gid_cache, &UserIDResolver::DoGetGroupName); 330b57cec5SDimitry Andric } 340b57cec5SDimitry Andric 350b57cec5SDimitry Andric /// Returns a resolver which returns a failure value for each query. Useful as 360b57cec5SDimitry Andric /// a fallback value for the case when we know all lookups will fail. 370b57cec5SDimitry Andric static UserIDResolver &GetNoopResolver(); 380b57cec5SDimitry Andric 390b57cec5SDimitry Andric protected: 40bdd1243dSDimitry Andric virtual std::optional<std::string> DoGetUserName(id_t uid) = 0; 41bdd1243dSDimitry Andric virtual std::optional<std::string> DoGetGroupName(id_t gid) = 0; 420b57cec5SDimitry Andric 430b57cec5SDimitry Andric private: 44bdd1243dSDimitry Andric using Map = llvm::DenseMap<id_t, std::optional<std::string>>; 450b57cec5SDimitry Andric 46bdd1243dSDimitry Andric std::optional<llvm::StringRef> 470b57cec5SDimitry Andric Get(id_t id, Map &cache, 48bdd1243dSDimitry Andric std::optional<std::string> (UserIDResolver::*do_get)(id_t)); 490b57cec5SDimitry Andric 500b57cec5SDimitry Andric std::mutex m_mutex; 510b57cec5SDimitry Andric Map m_uid_cache; 520b57cec5SDimitry Andric Map m_gid_cache; 530b57cec5SDimitry Andric }; 540b57cec5SDimitry Andric 550b57cec5SDimitry Andric } // namespace lldb_private 560b57cec5SDimitry Andric 575ffd83dbSDimitry Andric #endif // LLDB_UTILITY_USERIDRESOLVER_H 58