1 #define _POSIX_C_SOURCE 200809L
2 #include <limits.h>
3 #include <string.h>
4 #include <stdbool.h>
5 #include <stdlib.h>
6 #include <stdio.h>
7 #include <poll.h>
8 #include <time.h>
9 #include <unistd.h>
10 #include <wayland-client.h>
11 #include "log.h"
12 #include "loop.h"
13 
14 struct loop_fd_event {
15 	void (*callback)(int fd, short mask, void *data);
16 	void *data;
17 	struct wl_list link; // struct loop_fd_event::link
18 };
19 
20 struct loop_timer {
21 	void (*callback)(void *data);
22 	void *data;
23 	struct timespec expiry;
24 	bool removed;
25 	struct wl_list link; // struct loop_timer::link
26 };
27 
28 struct loop {
29 	struct pollfd *fds;
30 	int fd_length;
31 	int fd_capacity;
32 
33 	struct wl_list fd_events; // struct loop_fd_event::link
34 	struct wl_list timers; // struct loop_timer::link
35 };
36 
loop_create(void)37 struct loop *loop_create(void) {
38 	struct loop *loop = calloc(1, sizeof(struct loop));
39 	if (!loop) {
40 		swaylock_log(LOG_ERROR, "Unable to allocate memory for loop");
41 		return NULL;
42 	}
43 	loop->fd_capacity = 10;
44 	loop->fds = malloc(sizeof(struct pollfd) * loop->fd_capacity);
45 	wl_list_init(&loop->fd_events);
46 	wl_list_init(&loop->timers);
47 	return loop;
48 }
49 
loop_destroy(struct loop * loop)50 void loop_destroy(struct loop *loop) {
51 	struct loop_fd_event *event = NULL, *tmp_event = NULL;
52 	wl_list_for_each_safe(event, tmp_event, &loop->fd_events, link) {
53 		wl_list_remove(&event->link);
54 		free(event);
55 	}
56 	struct loop_timer *timer = NULL, *tmp_timer = NULL;
57 	wl_list_for_each_safe(timer, tmp_timer, &loop->timers, link) {
58 		wl_list_remove(&timer->link);
59 		free(timer);
60 	}
61 	free(loop->fds);
62 	free(loop);
63 }
64 
loop_poll(struct loop * loop)65 void loop_poll(struct loop *loop) {
66 	// Calculate next timer in ms
67 	int ms = INT_MAX;
68 	if (!wl_list_empty(&loop->timers)) {
69 		struct timespec now;
70 		clock_gettime(CLOCK_MONOTONIC, &now);
71 		struct loop_timer *timer = NULL;
72 		wl_list_for_each(timer, &loop->timers, link) {
73 			int timer_ms = (timer->expiry.tv_sec - now.tv_sec) * 1000;
74 			timer_ms += (timer->expiry.tv_nsec - now.tv_nsec) / 1000000;
75 			if (timer_ms < ms) {
76 				ms = timer_ms;
77 			}
78 		}
79 	}
80 	if (ms < 0) {
81 		ms = 0;
82 	}
83 
84 	poll(loop->fds, loop->fd_length, ms);
85 
86 	// Dispatch fds
87 	size_t fd_index = 0;
88 	struct loop_fd_event *event = NULL;
89 	wl_list_for_each(event, &loop->fd_events, link) {
90 		struct pollfd pfd = loop->fds[fd_index];
91 
92 		// Always send these events
93 		unsigned events = pfd.events | POLLHUP | POLLERR;
94 
95 		if (pfd.revents & events) {
96 			event->callback(pfd.fd, pfd.revents, event->data);
97 		}
98 
99 		++fd_index;
100 	}
101 
102 	// Dispatch timers
103 	if (!wl_list_empty(&loop->timers)) {
104 		struct timespec now;
105 		clock_gettime(CLOCK_MONOTONIC, &now);
106 		struct loop_timer *timer = NULL, *tmp_timer = NULL;
107 		wl_list_for_each_safe(timer, tmp_timer, &loop->timers, link) {
108 			if (timer->removed) {
109 				wl_list_remove(&timer->link);
110 				free(timer);
111 				continue;
112 			}
113 
114 			bool expired = timer->expiry.tv_sec < now.tv_sec ||
115 				(timer->expiry.tv_sec == now.tv_sec &&
116 				 timer->expiry.tv_nsec < now.tv_nsec);
117 			if (expired) {
118 				timer->callback(timer->data);
119 				wl_list_remove(&timer->link);
120 				free(timer);
121 			}
122 		}
123 	}
124 }
125 
loop_add_fd(struct loop * loop,int fd,short mask,void (* callback)(int fd,short mask,void * data),void * data)126 void loop_add_fd(struct loop *loop, int fd, short mask,
127 		void (*callback)(int fd, short mask, void *data), void *data) {
128 	struct loop_fd_event *event = calloc(1, sizeof(struct loop_fd_event));
129 	if (!event) {
130 		swaylock_log(LOG_ERROR, "Unable to allocate memory for event");
131 		return;
132 	}
133 	event->callback = callback;
134 	event->data = data;
135 	wl_list_insert(loop->fd_events.prev, &event->link);
136 
137 	struct pollfd pfd = {fd, mask, 0};
138 
139 	if (loop->fd_length == loop->fd_capacity) {
140 		loop->fd_capacity += 10;
141 		loop->fds = realloc(loop->fds,
142 				sizeof(struct pollfd) * loop->fd_capacity);
143 	}
144 
145 	loop->fds[loop->fd_length++] = pfd;
146 }
147 
loop_add_timer(struct loop * loop,int ms,void (* callback)(void * data),void * data)148 struct loop_timer *loop_add_timer(struct loop *loop, int ms,
149 		void (*callback)(void *data), void *data) {
150 	struct loop_timer *timer = calloc(1, sizeof(struct loop_timer));
151 	if (!timer) {
152 		swaylock_log(LOG_ERROR, "Unable to allocate memory for timer");
153 		return NULL;
154 	}
155 	timer->callback = callback;
156 	timer->data = data;
157 
158 	clock_gettime(CLOCK_MONOTONIC, &timer->expiry);
159 	timer->expiry.tv_sec += ms / 1000;
160 
161 	long int nsec = (ms % 1000) * 1000000;
162 	if (timer->expiry.tv_nsec + nsec >= 1000000000) {
163 		timer->expiry.tv_sec++;
164 		nsec -= 1000000000;
165 	}
166 	timer->expiry.tv_nsec += nsec;
167 
168 	wl_list_insert(&loop->timers, &timer->link);
169 
170 	return timer;
171 }
172 
loop_remove_fd(struct loop * loop,int fd)173 bool loop_remove_fd(struct loop *loop, int fd) {
174 	size_t fd_index = 0;
175 	struct loop_fd_event *event = NULL, *tmp_event = NULL;
176 	wl_list_for_each_safe(event, tmp_event, &loop->fd_events, link) {
177 		if (loop->fds[fd_index].fd == fd) {
178 			wl_list_remove(&event->link);
179 			free(event);
180 
181 			loop->fd_length--;
182 			memmove(&loop->fds[fd_index], &loop->fds[fd_index + 1],
183 					sizeof(struct pollfd) * (loop->fd_length - fd_index));
184 			return true;
185 		}
186 		++fd_index;
187 	}
188 	return false;
189 }
190 
loop_remove_timer(struct loop * loop,struct loop_timer * remove)191 bool loop_remove_timer(struct loop *loop, struct loop_timer *remove) {
192 	struct loop_timer *timer = NULL, *tmp_timer = NULL;
193 	wl_list_for_each_safe(timer, tmp_timer, &loop->timers, link) {
194 		if (timer == remove) {
195 			timer->removed = true;
196 			return true;
197 		}
198 	}
199 	return false;
200 }
201