/* Simple DirectMedia Layer Copyright (C) 1997-2016 Sam Lantinga This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions: 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 3. This notice may not be removed or altered from any source distribution. */ #include "../SDL_internal.h" /* General event handling code for SDL */ #include "SDL.h" #include "SDL_events.h" #include "SDL_syswm.h" #include "SDL_thread.h" #include "SDL_events_c.h" #include "../timer/SDL_timer_c.h" #if !SDL_JOYSTICK_DISABLED #include "../joystick/SDL_joystick_c.h" #endif #include "../video/SDL_sysvideo.h" /* An arbitrary limit so we don't have unbounded growth */ #define SDL_MAX_QUEUED_EVENTS 65535 /* Public data -- the event filter */ SDL_EventFilter SDL_EventOK = NULL; void *SDL_EventOKParam; typedef struct SDL_EventWatcher { SDL_EventFilter callback; void *userdata; struct SDL_EventWatcher *next; } SDL_EventWatcher; static SDL_EventWatcher *SDL_event_watchers = NULL; typedef struct { Uint32 bits[8]; } SDL_DisabledEventBlock; static SDL_DisabledEventBlock *SDL_disabled_events[256]; static Uint32 SDL_userevents = SDL_USEREVENT; /* Private data -- event queue */ typedef struct _SDL_EventEntry { SDL_Event event; SDL_SysWMmsg msg; struct _SDL_EventEntry *prev; struct _SDL_EventEntry *next; } SDL_EventEntry; typedef struct _SDL_SysWMEntry { SDL_SysWMmsg msg; struct _SDL_SysWMEntry *next; } SDL_SysWMEntry; static struct { SDL_mutex *lock; volatile SDL_bool active; volatile int count; volatile int max_events_seen; SDL_EventEntry *head; SDL_EventEntry *tail; SDL_EventEntry *free; SDL_SysWMEntry *wmmsg_used; SDL_SysWMEntry *wmmsg_free; } SDL_EventQ = { NULL, SDL_TRUE, 0, 0, NULL, NULL, NULL, NULL, NULL }; /* Public functions */ void SDL_StopEventLoop(void) { const char *report = SDL_GetHint("SDL_EVENT_QUEUE_STATISTICS"); int i; SDL_EventEntry *entry; SDL_SysWMEntry *wmmsg; if (SDL_EventQ.lock) { SDL_LockMutex(SDL_EventQ.lock); } SDL_EventQ.active = SDL_FALSE; if (report && SDL_atoi(report)) { SDL_Log("SDL EVENT QUEUE: Maximum events in-flight: %d\n", SDL_EventQ.max_events_seen); } /* Clean out EventQ */ for (entry = SDL_EventQ.head; entry; ) { SDL_EventEntry *next = entry->next; SDL_free(entry); entry = next; } for (entry = SDL_EventQ.free; entry; ) { SDL_EventEntry *next = entry->next; SDL_free(entry); entry = next; } for (wmmsg = SDL_EventQ.wmmsg_used; wmmsg; ) { SDL_SysWMEntry *next = wmmsg->next; SDL_free(wmmsg); wmmsg = next; } for (wmmsg = SDL_EventQ.wmmsg_free; wmmsg; ) { SDL_SysWMEntry *next = wmmsg->next; SDL_free(wmmsg); wmmsg = next; } SDL_EventQ.count = 0; SDL_EventQ.max_events_seen = 0; SDL_EventQ.head = NULL; SDL_EventQ.tail = NULL; SDL_EventQ.free = NULL; SDL_EventQ.wmmsg_used = NULL; SDL_EventQ.wmmsg_free = NULL; /* Clear disabled event state */ for (i = 0; i < SDL_arraysize(SDL_disabled_events); ++i) { SDL_free(SDL_disabled_events[i]); SDL_disabled_events[i] = NULL; } while (SDL_event_watchers) { SDL_EventWatcher *tmp = SDL_event_watchers; SDL_event_watchers = tmp->next; SDL_free(tmp); } SDL_EventOK = NULL; if (SDL_EventQ.lock) { SDL_UnlockMutex(SDL_EventQ.lock); SDL_DestroyMutex(SDL_EventQ.lock); SDL_EventQ.lock = NULL; } } /* This function (and associated calls) may be called more than once */ int SDL_StartEventLoop(void) { /* We'll leave the event queue alone, since we might have gotten some important events at launch (like SDL_DROPFILE) FIXME: Does this introduce any other bugs with events at startup? */ /* Create the lock and set ourselves active */ #if !SDL_THREADS_DISABLED if (!SDL_EventQ.lock) { SDL_EventQ.lock = SDL_CreateMutex(); } if (SDL_EventQ.lock == NULL) { return (-1); } #endif /* !SDL_THREADS_DISABLED */ /* Process most event types */ SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE); SDL_EventState(SDL_TEXTEDITING, SDL_DISABLE); SDL_EventState(SDL_SYSWMEVENT, SDL_DISABLE); SDL_EventQ.active = SDL_TRUE; return (0); } /* Add an event to the event queue -- called with the queue locked */ static int SDL_AddEvent(SDL_Event * event) { SDL_EventEntry *entry; if (SDL_EventQ.count >= SDL_MAX_QUEUED_EVENTS) { SDL_SetError("Event queue is full (%d events)", SDL_EventQ.count); return 0; } if (SDL_EventQ.free == NULL) { entry = (SDL_EventEntry *)SDL_malloc(sizeof(*entry)); if (!entry) { return 0; } } else { entry = SDL_EventQ.free; SDL_EventQ.free = entry->next; } entry->event = *event; if (event->type == SDL_SYSWMEVENT) { entry->msg = *event->syswm.msg; entry->event.syswm.msg = &entry->msg; } if (SDL_EventQ.tail) { SDL_EventQ.tail->next = entry; entry->prev = SDL_EventQ.tail; SDL_EventQ.tail = entry; entry->next = NULL; } else { SDL_assert(!SDL_EventQ.head); SDL_EventQ.head = entry; SDL_EventQ.tail = entry; entry->prev = NULL; entry->next = NULL; } ++SDL_EventQ.count; if (SDL_EventQ.count > SDL_EventQ.max_events_seen) { SDL_EventQ.max_events_seen = SDL_EventQ.count; } return 1; } /* Remove an event from the queue -- called with the queue locked */ static void SDL_CutEvent(SDL_EventEntry *entry) { if (entry->prev) { entry->prev->next = entry->next; } if (entry->next) { entry->next->prev = entry->prev; } if (entry == SDL_EventQ.head) { SDL_assert(entry->prev == NULL); SDL_EventQ.head = entry->next; } if (entry == SDL_EventQ.tail) { SDL_assert(entry->next == NULL); SDL_EventQ.tail = entry->prev; } entry->next = SDL_EventQ.free; SDL_EventQ.free = entry; SDL_assert(SDL_EventQ.count > 0); --SDL_EventQ.count; } /* Lock the event queue, take a peep at it, and unlock it */ int SDL_PeepEvents(SDL_Event * events, int numevents, SDL_eventaction action, Uint32 minType, Uint32 maxType) { int i, used; /* Don't look after we've quit */ if (!SDL_EventQ.active) { /* We get a few spurious events at shutdown, so don't warn then */ if (action != SDL_ADDEVENT) { SDL_SetError("The event system has been shut down"); } return (-1); } /* Lock the event queue */ used = 0; if (!SDL_EventQ.lock || SDL_LockMutex(SDL_EventQ.lock) == 0) { if (action == SDL_ADDEVENT) { for (i = 0; i < numevents; ++i) { used += SDL_AddEvent(&events[i]); } } else { SDL_EventEntry *entry, *next; SDL_SysWMEntry *wmmsg, *wmmsg_next; SDL_Event tmpevent; Uint32 type; /* If 'events' is NULL, just see if they exist */ if (events == NULL) { action = SDL_PEEKEVENT; numevents = 1; events = &tmpevent; } /* Clean out any used wmmsg data FIXME: Do we want to retain the data for some period of time? */ for (wmmsg = SDL_EventQ.wmmsg_used; wmmsg; wmmsg = wmmsg_next) { wmmsg_next = wmmsg->next; wmmsg->next = SDL_EventQ.wmmsg_free; SDL_EventQ.wmmsg_free = wmmsg; } SDL_EventQ.wmmsg_used = NULL; for (entry = SDL_EventQ.head; entry && used < numevents; entry = next) { next = entry->next; type = entry->event.type; if (minType <= type && type <= maxType) { events[used] = entry->event; if (entry->event.type == SDL_SYSWMEVENT) { /* We need to copy the wmmsg somewhere safe. For now we'll guarantee it's valid at least until the next call to SDL_PeepEvents() */ if (SDL_EventQ.wmmsg_free) { wmmsg = SDL_EventQ.wmmsg_free; SDL_EventQ.wmmsg_free = wmmsg->next; } else { wmmsg = (SDL_SysWMEntry *)SDL_malloc(sizeof(*wmmsg)); } wmmsg->msg = *entry->event.syswm.msg; wmmsg->next = SDL_EventQ.wmmsg_used; SDL_EventQ.wmmsg_used = wmmsg; events[used].syswm.msg = &wmmsg->msg; } ++used; if (action == SDL_GETEVENT) { SDL_CutEvent(entry); } } } } SDL_UnlockMutex(SDL_EventQ.lock); } else { return SDL_SetError("Couldn't lock event queue"); } return (used); } SDL_bool SDL_HasEvent(Uint32 type) { return (SDL_PeepEvents(NULL, 0, SDL_PEEKEVENT, type, type) > 0); } SDL_bool SDL_HasEvents(Uint32 minType, Uint32 maxType) { return (SDL_PeepEvents(NULL, 0, SDL_PEEKEVENT, minType, maxType) > 0); } void SDL_FlushEvent(Uint32 type) { SDL_FlushEvents(type, type); } void SDL_FlushEvents(Uint32 minType, Uint32 maxType) { /* Don't look after we've quit */ if (!SDL_EventQ.active) { return; } /* Make sure the events are current */ #if 0 /* Actually, we can't do this since we might be flushing while processing a resize event, and calling this might trigger further resize events. */ SDL_PumpEvents(); #endif /* Lock the event queue */ if (SDL_LockMutex(SDL_EventQ.lock) == 0) { SDL_EventEntry *entry, *next; Uint32 type; for (entry = SDL_EventQ.head; entry; entry = next) { next = entry->next; type = entry->event.type; if (minType <= type && type <= maxType) { SDL_CutEvent(entry); } } SDL_UnlockMutex(SDL_EventQ.lock); } } /* Run the system dependent event loops */ void SDL_PumpEvents(void) { SDL_VideoDevice *_this = SDL_GetVideoDevice(); /* Get events from the video subsystem */ if (_this) { _this->PumpEvents(_this); } #if !SDL_JOYSTICK_DISABLED /* Check for joystick state change */ if ((!SDL_disabled_events[SDL_JOYAXISMOTION >> 8] || SDL_JoystickEventState(SDL_QUERY))) { SDL_JoystickUpdate(); } #endif SDL_SendPendingQuit(); /* in case we had a signal handler fire, etc. */ } /* Public functions */ int SDL_PollEvent(SDL_Event * event) { return SDL_WaitEventTimeout(event, 0); } int SDL_WaitEvent(SDL_Event * event) { return SDL_WaitEventTimeout(event, -1); } int SDL_WaitEventTimeout(SDL_Event * event, int timeout) { Uint32 expiration = 0; if (timeout > 0) expiration = SDL_GetTicks() + timeout; for (;;) { SDL_PumpEvents(); switch (SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_FIRSTEVENT, SDL_LASTEVENT)) { case -1: return 0; case 1: return 1; case 0: if (timeout == 0) { /* Polling and no events, just return */ return 0; } if (timeout > 0 && SDL_TICKS_PASSED(SDL_GetTicks(), expiration)) { /* Timeout expired and no events */ return 0; } SDL_Delay(10); break; } } } int SDL_PushEvent(SDL_Event * event) { SDL_EventWatcher *curr; event->common.timestamp = SDL_GetTicks(); if (SDL_EventOK && !SDL_EventOK(SDL_EventOKParam, event)) { return 0; } for (curr = SDL_event_watchers; curr; curr = curr->next) { curr->callback(curr->userdata, event); } if (SDL_PeepEvents(event, 1, SDL_ADDEVENT, 0, 0) <= 0) { return -1; } SDL_GestureProcessEvent(event); return 1; } void SDL_SetEventFilter(SDL_EventFilter filter, void *userdata) { /* Set filter and discard pending events */ SDL_EventOK = NULL; SDL_FlushEvents(SDL_FIRSTEVENT, SDL_LASTEVENT); SDL_EventOKParam = userdata; SDL_EventOK = filter; } SDL_bool SDL_GetEventFilter(SDL_EventFilter * filter, void **userdata) { if (filter) { *filter = SDL_EventOK; } if (userdata) { *userdata = SDL_EventOKParam; } return SDL_EventOK ? SDL_TRUE : SDL_FALSE; } /* FIXME: This is not thread-safe yet */ void SDL_AddEventWatch(SDL_EventFilter filter, void *userdata) { SDL_EventWatcher *watcher, *tail; watcher = (SDL_EventWatcher *)SDL_malloc(sizeof(*watcher)); if (!watcher) { /* Uh oh... */ return; } /* create the watcher */ watcher->callback = filter; watcher->userdata = userdata; watcher->next = NULL; /* add the watcher to the end of the list */ if (SDL_event_watchers) { for (tail = SDL_event_watchers; tail->next; tail = tail->next) { continue; } tail->next = watcher; } else { SDL_event_watchers = watcher; } } /* FIXME: This is not thread-safe yet */ void SDL_DelEventWatch(SDL_EventFilter filter, void *userdata) { SDL_EventWatcher *prev = NULL; SDL_EventWatcher *curr; for (curr = SDL_event_watchers; curr; prev = curr, curr = curr->next) { if (curr->callback == filter && curr->userdata == userdata) { if (prev) { prev->next = curr->next; } else { SDL_event_watchers = curr->next; } SDL_free(curr); break; } } } void SDL_FilterEvents(SDL_EventFilter filter, void *userdata) { if (SDL_EventQ.lock && SDL_LockMutex(SDL_EventQ.lock) == 0) { SDL_EventEntry *entry, *next; for (entry = SDL_EventQ.head; entry; entry = next) { next = entry->next; if (!filter(userdata, &entry->event)) { SDL_CutEvent(entry); } } SDL_UnlockMutex(SDL_EventQ.lock); } } Uint8 SDL_EventState(Uint32 type, int state) { Uint8 current_state; Uint8 hi = ((type >> 8) & 0xff); Uint8 lo = (type & 0xff); if (SDL_disabled_events[hi] && (SDL_disabled_events[hi]->bits[lo/32] & (1 << (lo&31)))) { current_state = SDL_DISABLE; } else { current_state = SDL_ENABLE; } if (state != current_state) { switch (state) { case SDL_DISABLE: /* Disable this event type and discard pending events */ if (!SDL_disabled_events[hi]) { SDL_disabled_events[hi] = (SDL_DisabledEventBlock*) SDL_calloc(1, sizeof(SDL_DisabledEventBlock)); if (!SDL_disabled_events[hi]) { /* Out of memory, nothing we can do... */ break; } } SDL_disabled_events[hi]->bits[lo/32] |= (1 << (lo&31)); SDL_FlushEvent(type); break; case SDL_ENABLE: SDL_disabled_events[hi]->bits[lo/32] &= ~(1 << (lo&31)); break; default: /* Querying state... */ break; } } return current_state; } Uint32 SDL_RegisterEvents(int numevents) { Uint32 event_base; if ((numevents > 0) && (SDL_userevents+numevents <= SDL_LASTEVENT)) { event_base = SDL_userevents; SDL_userevents += numevents; } else { event_base = (Uint32)-1; } return event_base; } int SDL_SendAppEvent(SDL_EventType eventType) { int posted; posted = 0; if (SDL_GetEventState(eventType) == SDL_ENABLE) { SDL_Event event; event.type = eventType; posted = (SDL_PushEvent(&event) > 0); } return (posted); } int SDL_SendSysWMEvent(SDL_SysWMmsg * message) { int posted; posted = 0; if (SDL_GetEventState(SDL_SYSWMEVENT) == SDL_ENABLE) { SDL_Event event; SDL_memset(&event, 0, sizeof(event)); event.type = SDL_SYSWMEVENT; event.syswm.msg = message; posted = (SDL_PushEvent(&event) > 0); } /* Update internal event state */ return (posted); } int SDL_SendKeymapChangedEvent(void) { return SDL_SendAppEvent(SDL_KEYMAPCHANGED); } /* vi: set ts=4 sw=4 expandtab: */