ae_epoll.c

   1 /* Linux epoll(2) based ae.c module
   2  * Copyright (C) 2009 Salvatore Sanfilippo - antirez@gmail.com
   3  * Released under the BSD license. See the COPYING file for more info. */
   4
   5 #include <sys/epoll.h>
   6
   7 typedef struct aeApiState {
   8     int epfd;
   9     struct epoll_event events[AE_SETSIZE];
  10 } aeApiState;
  11
  12 static int aeApiCreate(aeEventLoop *eventLoop) {
  13     aeApiState *state = zmalloc(sizeof(aeApiState));
  14
  15     if (!state) return -1;
  16     state->epfd = epoll_create(1024); /* 1024 is just an hint for the kernel */
  17     if (state->epfd == -1) return -1;
  18     eventLoop->apidata = state;
  19     return 0;
  20 }
  21
  22 static void aeApiFree(aeEventLoop *eventLoop) {
  23     aeApiState *state = eventLoop->apidata;
  24
  25     close(state->epfd);
  26     zfree(state);
  27 }
  28
  29 static int aeApiAddEvent(aeEventLoop *eventLoop, int fd, int mask) {
  30     aeApiState *state = eventLoop->apidata;
  31     struct epoll_event ee;
  32     int op = eventLoop->events[fd].mask == AE_NONE ?
  33             EPOLL_CTL_ADD : EPOLL_CTL_MOD;
  34
  35     ee.events = 0;
  36     if (mask & AE_READABLE) ee.events |= EPOLLIN;
  37     if (mask & AE_WRITABLE) ee.events |= EPOLLOUT;
  38     if (mask & AE_EXCEPTION) ee.events |= EPOLLPRI;
  39     ee.data.fd = fd;
  40     if (epoll_ctl(state->epfd,op,fd,&ee) == -1) return -1;
  41     return 0;
  42 }
  43
  44 static void aeApiDelEvent(aeEventLoop *eventLoop, int fd, int delmask) {
  45     aeApiState *state = eventLoop->apidata;
  46     struct epoll_event ee;
  47     int mask = eventLoop->events[fd].mask & (~delmask);
  48
  49     ee.events = 0;
  50     if (mask & AE_READABLE) ee.events |= EPOLLIN;
  51     if (mask & AE_WRITABLE) ee.events |= EPOLLOUT;
  52     if (mask & AE_EXCEPTION) ee.events |= EPOLLPRI;
  53     ee.data.fd = fd;
  54     if (mask != AE_NONE) {
  55         epoll_ctl(state->epfd,EPOLL_CTL_MOD,fd,&ee);
  56     } else {
  57         /* Note, Kernel < 2.6.9 requires a non null event pointer even for
  58          * EPOLL_CTL_DEL. */
  59         epoll_ctl(state->epfd,EPOLL_CTL_DEL,fd,&ee);
  60     }
  61 }
  62
  63 static int aeApiPoll(aeEventLoop *eventLoop, struct timeval *tvp) {
  64     aeApiState *state = eventLoop->apidata;
  65     int retval, numevents = 0;
  66
  67     retval = epoll_wait(state->epfd,state->events,AE_SETSIZE,
  68             tvp ? (tvp->tv_sec*1000 + tvp->tv_usec/1000) : -1);
  69     if (retval > 0) {
  70         int j;
  71
  72         numevents = retval;
  73         for (j = 0; j < numevents; j++) {
  74             int mask = 0;
  75             struct epoll_event *e = state->events+j;
  76
  77             if (e->events & EPOLLIN) mask |= AE_READABLE;
  78             if (e->events & EPOLLOUT) mask |= AE_WRITABLE;
  79             if (e->events & EPOLLPRI) mask |= AE_EXCEPTION;
  80             eventLoop->fired[j].fd = e->data.fd;
  81             eventLoop->fired[j].mask = mask;
  82         }
  83     }
  84     return numevents;
  85 }