1 /* 2 * Copyright (C) 2023 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef BERBERIS_GUEST_OS_PRIMITIVES_GUEST_SIGNAL_ACTION_H_ 18 #define BERBERIS_GUEST_OS_PRIMITIVES_GUEST_SIGNAL_ACTION_H_ 19 20 #include <array> 21 #include <csignal> 22 23 #include "berberis/base/checks.h" 24 #include "berberis/guest_os_primitives/guest_signal.h" 25 #include "berberis/guest_os_primitives/guest_signal_arch.h" 26 27 namespace berberis { 28 29 // Signal is 'claimed' when it has guest handler/action. For a claimed signal, actual host action 30 // is a wrapper that invokes guest code (or suspends handling until region exit). 31 class GuestSignalAction { 32 public: 33 using host_sa_sigaction_t = void (*)(int, siginfo_t*, void*); 34 GuestSignalAction()35 constexpr GuestSignalAction() 36 : claimed_guest_sa_{.guest_sa_sigaction = Guest_SIG_DFL, .sa_flags = 0, .sa_mask = {}} {} 37 38 GuestSignalAction(const GuestSignalAction& other) = default; 39 GuestSignalAction& operator=(const GuestSignalAction& other) = default; 40 41 bool Change(int sig, 42 const Guest_sigaction* new_sa, 43 host_sa_sigaction_t claimed_host_sa_sigaction, 44 Guest_sigaction* old_sa, 45 int* error); 46 GetClaimedGuestAction()47 const Guest_sigaction& GetClaimedGuestAction() const { 48 CHECK(IsClaimed()); 49 return claimed_guest_sa_; 50 } 51 52 private: IsClaimed()53 bool IsClaimed() const { return claimed_guest_sa_.guest_sa_sigaction != Guest_SIG_DFL; } 54 Claim(const Guest_sigaction * sa)55 void Claim(const Guest_sigaction* sa) { 56 CHECK_NE(Guest_SIG_DFL, sa->guest_sa_sigaction); 57 claimed_guest_sa_ = *sa; 58 } 59 Unclaim()60 void Unclaim() { claimed_guest_sa_.guest_sa_sigaction = Guest_SIG_DFL; } 61 62 Guest_sigaction claimed_guest_sa_; // Guest_SIG_DFL when not claimed. 63 }; 64 65 // It's essentially a typedef. But we make it a class to forward declare in guest_thread.h. 66 class GuestSignalActionsTable : public std::array<GuestSignalAction, Guest__KERNEL__NSIG> { 67 public: 68 GuestSignalActionsTable() = default; 69 GuestSignalActionsTable(const GuestSignalActionsTable& other) = default; 70 GuestSignalActionsTable& operator=(const GuestSignalActionsTable& other) = default; 71 }; 72 73 } // namespace berberis 74 75 #endif // BERBERIS_GUEST_OS_PRIMITIVES_GUEST_SIGNAL_ACTION_H_ 76