1 /* 2 * Copyright 2007-2011, Ingo Weinhold, ingo_weinhold@gmx.de. 3 * Copyright 2019, Haiku, Inc. All rights reserved. 4 * Distributed under the terms of the MIT License. 5 */ 6 #ifndef _KERNEL_CONDITION_VARIABLE_H 7 #define _KERNEL_CONDITION_VARIABLE_H 8 9 10 #include <OS.h> 11 12 #include <debug.h> 13 14 #ifdef __cplusplus 15 16 #include <util/DoublyLinkedList.h> 17 #include <util/OpenHashTable.h> 18 19 20 struct ConditionVariable; 21 22 23 struct ConditionVariableEntry 24 : DoublyLinkedListLinkImpl<ConditionVariableEntry> { 25 public: 26 ConditionVariableEntry(); 27 ~ConditionVariableEntry(); 28 29 bool Add(const void* object); 30 status_t Wait(uint32 flags = 0, bigtime_t timeout = 0); 31 status_t Wait(const void* object, uint32 flags = 0, 32 bigtime_t timeout = 0); 33 34 inline status_t WaitStatus() const { return fWaitStatus; } 35 36 inline ConditionVariable* Variable() const { return fVariable; } 37 38 private: 39 inline void _AddToLockedVariable(ConditionVariable* variable); 40 void _RemoveFromVariable(); 41 42 private: 43 ConditionVariable* fVariable; 44 Thread* fThread; 45 status_t fWaitStatus; 46 47 friend struct ConditionVariable; 48 }; 49 50 51 struct ConditionVariable { 52 public: 53 void Init(const void* object, 54 const char* objectType); 55 // for anonymous (unpublished) cvars 56 57 void Publish(const void* object, 58 const char* objectType); 59 void Unpublish(); 60 61 inline void NotifyOne(status_t result = B_OK); 62 inline void NotifyAll(status_t result = B_OK); 63 64 static void NotifyOne(const void* object, status_t result); 65 static void NotifyAll(const void* object, status_t result); 66 // (both methods) caller must ensure that 67 // the variable is not unpublished 68 // concurrently 69 70 void Add(ConditionVariableEntry* entry); 71 72 status_t Wait(uint32 flags = 0, bigtime_t timeout = 0); 73 // all-in one, i.e. doesn't need a 74 // ConditionVariableEntry 75 76 const void* Object() const { return fObject; } 77 const char* ObjectType() const { return fObjectType; } 78 79 static void ListAll(); 80 void Dump() const; 81 82 private: 83 void _Notify(bool all, status_t result); 84 void _NotifyLocked(bool all, status_t result); 85 86 protected: 87 typedef DoublyLinkedList<ConditionVariableEntry> EntryList; 88 89 const void* fObject; 90 const char* fObjectType; 91 92 spinlock fLock; 93 EntryList fEntries; 94 int32 fEntriesCount; 95 96 ConditionVariable* fNext; 97 98 friend struct ConditionVariableEntry; 99 friend struct ConditionVariableHashDefinition; 100 }; 101 102 103 inline void 104 ConditionVariable::NotifyOne(status_t result) 105 { 106 _Notify(false, result); 107 } 108 109 110 inline void 111 ConditionVariable::NotifyAll(status_t result) 112 { 113 _Notify(true, result); 114 } 115 116 117 extern "C" { 118 #endif // __cplusplus 119 120 extern void condition_variable_init(); 121 122 #ifdef __cplusplus 123 } // extern "C" 124 #endif 125 126 #endif /* _KERNEL_CONDITION_VARIABLE_H */ 127