1 /* 2 * Notifier lists 3 * 4 * Copyright IBM, Corp. 2010 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #ifndef QEMU_NOTIFY_H 15 #define QEMU_NOTIFY_H 16 17 #include "qemu/queue.h" 18 19 typedef struct Notifier Notifier; 20 21 struct Notifier 22 { 23 void (*notify)(Notifier *notifier, void *data); 24 QLIST_ENTRY(Notifier) node; 25 }; 26 27 typedef struct NotifierList 28 { 29 QLIST_HEAD(, Notifier) notifiers; 30 } NotifierList; 31 32 #define NOTIFIER_LIST_INITIALIZER(head) \ 33 { QLIST_HEAD_INITIALIZER((head).notifiers) } 34 35 void notifier_list_init(NotifierList *list); 36 37 void notifier_list_add(NotifierList *list, Notifier *notifier); 38 39 void notifier_remove(Notifier *notifier); 40 41 void notifier_list_notify(NotifierList *list, void *data); 42 43 /* Same as Notifier but allows .notify() to return errors */ 44 typedef struct NotifierWithReturn NotifierWithReturn; 45 46 struct NotifierWithReturn { 47 /** 48 * Return 0 on success (next notifier will be invoked), otherwise 49 * notifier_with_return_list_notify() will stop and return the value. 50 */ 51 int (*notify)(NotifierWithReturn *notifier, void *data); 52 QLIST_ENTRY(NotifierWithReturn) node; 53 }; 54 55 typedef struct NotifierWithReturnList { 56 QLIST_HEAD(, NotifierWithReturn) notifiers; 57 } NotifierWithReturnList; 58 59 #define NOTIFIER_WITH_RETURN_LIST_INITIALIZER(head) \ 60 { QLIST_HEAD_INITIALIZER((head).notifiers) } 61 62 void notifier_with_return_list_init(NotifierWithReturnList *list); 63 64 void notifier_with_return_list_add(NotifierWithReturnList *list, 65 NotifierWithReturn *notifier); 66 67 void notifier_with_return_remove(NotifierWithReturn *notifier); 68 69 int notifier_with_return_list_notify(NotifierWithReturnList *list, 70 void *data); 71 72 #endif 73