1 /* //device/libs/telephony/ril_event.cpp
2 **
3 ** Copyright 2008, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17
18 #define LOG_TAG "RILC"
19
20 #include <stdlib.h>
21 #include <unistd.h>
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <utils/Log.h>
25 #include <ril_event.h>
26 #include <string.h>
27 #include <sys/time.h>
28 #include <time.h>
29
30 #include <pthread.h>
31 static pthread_mutex_t listMutex;
32 #define MUTEX_ACQUIRE() pthread_mutex_lock(&listMutex)
33 #define MUTEX_RELEASE() pthread_mutex_unlock(&listMutex)
34 #define MUTEX_INIT() pthread_mutex_init(&listMutex, NULL)
35 #define MUTEX_DESTROY() pthread_mutex_destroy(&listMutex)
36
37 #ifndef timeradd
38 #define timeradd(tvp, uvp, vvp) \
39 do { \
40 (vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec; \
41 (vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec; \
42 if ((vvp)->tv_usec >= 1000000) { \
43 (vvp)->tv_sec++; \
44 (vvp)->tv_usec -= 1000000; \
45 } \
46 } while (0)
47 #endif
48
49 #ifndef timercmp
50 #define timercmp(a, b, op) \
51 ((a)->tv_sec == (b)->tv_sec \
52 ? (a)->tv_usec op (b)->tv_usec \
53 : (a)->tv_sec op (b)->tv_sec)
54 #endif
55
56 #ifndef timersub
57 #define timersub(a, b, res) \
58 do { \
59 (res)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
60 (res)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
61 if ((res)->tv_usec < 0) { \
62 (res)->tv_usec += 1000000; \
63 (res)->tv_sec -= 1; \
64 } \
65 } while(0);
66 #endif
67
68 static fd_set readFds;
69 static int nfds = 0;
70
71 static struct ril_event * watch_table[MAX_FD_EVENTS];
72 static struct ril_event timer_list;
73 static struct ril_event pending_list;
74
75 #define DEBUG 0
76
77 #if DEBUG
78 #define dlog(x...) RLOGD( x )
dump_event(struct ril_event * ev)79 static void dump_event(struct ril_event * ev)
80 {
81 dlog("~~~~ Event %x ~~~~", (unsigned int)ev);
82 dlog(" next = %x", (unsigned int)ev->next);
83 dlog(" prev = %x", (unsigned int)ev->prev);
84 dlog(" fd = %d", ev->fd);
85 dlog(" pers = %d", ev->persist);
86 dlog(" timeout = %ds + %dus", (int)ev->timeout.tv_sec, (int)ev->timeout.tv_usec);
87 dlog(" func = %x", (unsigned int)ev->func);
88 dlog(" param = %x", (unsigned int)ev->param);
89 dlog("~~~~~~~~~~~~~~~~~~");
90 }
91 #else
92 #define dlog(x...) do {} while(0)
93 #define dump_event(x) do {} while(0)
94 #endif
95
getNow(struct timeval * tv)96 static void getNow(struct timeval * tv)
97 {
98 struct timespec ts;
99 clock_gettime(CLOCK_MONOTONIC, &ts);
100 tv->tv_sec = ts.tv_sec;
101 tv->tv_usec = ts.tv_nsec/1000;
102 }
103
init_list(struct ril_event * list)104 static void init_list(struct ril_event * list)
105 {
106 memset(list, 0, sizeof(struct ril_event));
107 list->next = list;
108 list->prev = list;
109 list->fd = -1;
110 }
111
addToList(struct ril_event * ev,struct ril_event * list)112 static void addToList(struct ril_event * ev, struct ril_event * list)
113 {
114 ev->next = list;
115 ev->prev = list->prev;
116 ev->prev->next = ev;
117 list->prev = ev;
118 dump_event(ev);
119 }
120
removeFromList(struct ril_event * ev)121 static void removeFromList(struct ril_event * ev)
122 {
123 dlog("~~~~ +removeFromList ~~~~");
124 dump_event(ev);
125
126 ev->next->prev = ev->prev;
127 ev->prev->next = ev->next;
128 ev->next = NULL;
129 ev->prev = NULL;
130 dlog("~~~~ -removeFromList ~~~~");
131 }
132
133
removeWatch(struct ril_event * ev,int index)134 static void removeWatch(struct ril_event * ev, int index)
135 {
136 dlog("~~~~ +removeWatch ~~~~");
137 watch_table[index] = NULL;
138 ev->index = -1;
139
140 FD_CLR(ev->fd, &readFds);
141
142 if (ev->fd+1 == nfds) {
143 int n = 0;
144
145 for (int i = 0; i < MAX_FD_EVENTS; i++) {
146 struct ril_event * rev = watch_table[i];
147
148 if ((rev != NULL) && (rev->fd > n)) {
149 n = rev->fd;
150 }
151 }
152 nfds = n + 1;
153 dlog("~~~~ nfds = %d ~~~~", nfds);
154 }
155 dlog("~~~~ -removeWatch ~~~~");
156 }
157
processTimeouts()158 static void processTimeouts()
159 {
160 dlog("~~~~ +processTimeouts ~~~~");
161 MUTEX_ACQUIRE();
162 struct timeval now;
163 struct ril_event * tev = timer_list.next;
164 struct ril_event * next;
165
166 getNow(&now);
167 // walk list, see if now >= ev->timeout for any events
168
169 dlog("~~~~ Looking for timers <= %ds + %dus ~~~~", (int)now.tv_sec, (int)now.tv_usec);
170 while ((tev != &timer_list) && (timercmp(&now, &tev->timeout, >))) {
171 // Timer expired
172 dlog("~~~~ firing timer ~~~~");
173 next = tev->next;
174 removeFromList(tev);
175 addToList(tev, &pending_list);
176 tev = next;
177 }
178 MUTEX_RELEASE();
179 dlog("~~~~ -processTimeouts ~~~~");
180 }
181
processReadReadies(fd_set * rfds,int n)182 static void processReadReadies(fd_set * rfds, int n)
183 {
184 dlog("~~~~ +processReadReadies (%d) ~~~~", n);
185 MUTEX_ACQUIRE();
186
187 for (int i = 0; (i < MAX_FD_EVENTS) && (n > 0); i++) {
188 struct ril_event * rev = watch_table[i];
189 if (rev != NULL && FD_ISSET(rev->fd, rfds)) {
190 addToList(rev, &pending_list);
191 if (rev->persist == false) {
192 removeWatch(rev, i);
193 }
194 n--;
195 }
196 }
197
198 MUTEX_RELEASE();
199 dlog("~~~~ -processReadReadies (%d) ~~~~", n);
200 }
201
firePending()202 static void firePending()
203 {
204 dlog("~~~~ +firePending ~~~~");
205 struct ril_event * ev = pending_list.next;
206 while (ev != &pending_list) {
207 struct ril_event * next = ev->next;
208 removeFromList(ev);
209 ev->func(ev->fd, 0, ev->param);
210 ev = next;
211 }
212 dlog("~~~~ -firePending ~~~~");
213 }
214
calcNextTimeout(struct timeval * tv)215 static int calcNextTimeout(struct timeval * tv)
216 {
217 struct ril_event * tev = timer_list.next;
218 struct timeval now;
219
220 getNow(&now);
221
222 // Sorted list, so calc based on first node
223 if (tev == &timer_list) {
224 // no pending timers
225 return -1;
226 }
227
228 dlog("~~~~ now = %ds + %dus ~~~~", (int)now.tv_sec, (int)now.tv_usec);
229 dlog("~~~~ next = %ds + %dus ~~~~",
230 (int)tev->timeout.tv_sec, (int)tev->timeout.tv_usec);
231 if (timercmp(&tev->timeout, &now, >)) {
232 timersub(&tev->timeout, &now, tv);
233 } else {
234 // timer already expired.
235 tv->tv_sec = tv->tv_usec = 0;
236 }
237 return 0;
238 }
239
240 // Initialize internal data structs
ril_event_init()241 void ril_event_init()
242 {
243 MUTEX_INIT();
244
245 FD_ZERO(&readFds);
246 init_list(&timer_list);
247 init_list(&pending_list);
248 memset(watch_table, 0, sizeof(watch_table));
249 }
250
251 // Initialize an event
ril_event_set(struct ril_event * ev,int fd,bool persist,ril_event_cb func,void * param)252 void ril_event_set(struct ril_event * ev, int fd, bool persist, ril_event_cb func, void * param)
253 {
254 dlog("~~~~ ril_event_set %x ~~~~", (unsigned int)ev);
255 memset(ev, 0, sizeof(struct ril_event));
256 ev->fd = fd;
257 ev->index = -1;
258 ev->persist = persist;
259 ev->func = func;
260 ev->param = param;
261 fcntl(fd, F_SETFL, O_NONBLOCK);
262 }
263
264 // Add event to watch list
ril_event_add(struct ril_event * ev)265 void ril_event_add(struct ril_event * ev)
266 {
267 dlog("~~~~ +ril_event_add ~~~~");
268 MUTEX_ACQUIRE();
269 for (int i = 0; i < MAX_FD_EVENTS; i++) {
270 if (watch_table[i] == NULL) {
271 watch_table[i] = ev;
272 ev->index = i;
273 dlog("~~~~ added at %d ~~~~", i);
274 dump_event(ev);
275 FD_SET(ev->fd, &readFds);
276 if (ev->fd >= nfds) nfds = ev->fd+1;
277 dlog("~~~~ nfds = %d ~~~~", nfds);
278 break;
279 }
280 }
281 MUTEX_RELEASE();
282 dlog("~~~~ -ril_event_add ~~~~");
283 }
284
285 // Add timer event
ril_timer_add(struct ril_event * ev,struct timeval * tv)286 void ril_timer_add(struct ril_event * ev, struct timeval * tv)
287 {
288 dlog("~~~~ +ril_timer_add ~~~~");
289 MUTEX_ACQUIRE();
290
291 struct ril_event * list;
292 if (tv != NULL) {
293 // add to timer list
294 list = timer_list.next;
295 ev->fd = -1; // make sure fd is invalid
296
297 struct timeval now;
298 getNow(&now);
299 timeradd(&now, tv, &ev->timeout);
300
301 // keep list sorted
302 while (timercmp(&list->timeout, &ev->timeout, < )
303 && (list != &timer_list)) {
304 list = list->next;
305 }
306 // list now points to the first event older than ev
307 addToList(ev, list);
308 }
309
310 MUTEX_RELEASE();
311 dlog("~~~~ -ril_timer_add ~~~~");
312 }
313
314 // Remove event from watch or timer list
ril_event_del(struct ril_event * ev)315 void ril_event_del(struct ril_event * ev)
316 {
317 dlog("~~~~ +ril_event_del ~~~~");
318 MUTEX_ACQUIRE();
319
320 if (ev->index < 0 || ev->index >= MAX_FD_EVENTS) {
321 MUTEX_RELEASE();
322 return;
323 }
324
325 removeWatch(ev, ev->index);
326
327 MUTEX_RELEASE();
328 dlog("~~~~ -ril_event_del ~~~~");
329 }
330
331 #if DEBUG
printReadies(fd_set * rfds)332 static void printReadies(fd_set * rfds)
333 {
334 for (int i = 0; (i < MAX_FD_EVENTS); i++) {
335 struct ril_event * rev = watch_table[i];
336 if (rev != NULL && FD_ISSET(rev->fd, rfds)) {
337 dlog("DON: fd=%d is ready", rev->fd);
338 }
339 }
340 }
341 #else
342 #define printReadies(rfds) do {} while(0)
343 #endif
344
ril_event_loop()345 void ril_event_loop()
346 {
347 int n;
348 fd_set rfds;
349 struct timeval tv;
350 struct timeval * ptv;
351
352
353 for (;;) {
354
355 // make local copy of read fd_set
356 memcpy(&rfds, &readFds, sizeof(fd_set));
357 if (-1 == calcNextTimeout(&tv)) {
358 // no pending timers; block indefinitely
359 dlog("~~~~ no timers; blocking indefinitely ~~~~");
360 ptv = NULL;
361 } else {
362 dlog("~~~~ blocking for %ds + %dus ~~~~", (int)tv.tv_sec, (int)tv.tv_usec);
363 ptv = &tv;
364 }
365 printReadies(&rfds);
366 n = select(nfds, &rfds, NULL, NULL, ptv);
367 printReadies(&rfds);
368 dlog("~~~~ %d events fired ~~~~", n);
369 if (n < 0) {
370 if (errno == EINTR) continue;
371
372 RLOGE("ril_event: select error (%d)", errno);
373 // bail?
374 return;
375 }
376
377 // Check for timeouts
378 processTimeouts();
379 // Check for read-ready
380 processReadReadies(&rfds, n);
381 // Fire away
382 firePending();
383 }
384 }
385