linux.c

   1 #define _XOPEN_SOURCE 600
   2
   3 #include "dat.h"
   4 #include <unistd.h>
   5 #include <sys/types.h>
   6 #include <stdint.h>
   7 #include <fcntl.h>
   8 #include <stdlib.h>
   9 #include <errno.h>
  10 #include <sys/epoll.h>
  11
  12 #ifndef EPOLLRDHUP
  13 #define EPOLLRDHUP 0x2000
  14 #endif
  15
  16 static int epfd;
  17
  18
  19 int
  20 sockinit(void)
  21 {
  22     epfd = epoll_create(1);
  23     if (epfd == -1) {
  24         twarn("epoll_create");
  25         return -1;
  26     }
  27     return 0;
  28 }
  29
  30
  31 int
  32 sockwant(Socket *s, int rw)
  33 {
  34     int op;
  35
  36     if (!s->added && !rw) {
  37         return 0;
  38     } else if (!s->added && rw) {
  39         s->added = 1;
  40         op = EPOLL_CTL_ADD;
  41     } else if (!rw) {
  42         op = EPOLL_CTL_DEL;
  43     } else {
  44         op = EPOLL_CTL_MOD;
  45     }
  46
  47     struct epoll_event ev = {.events=0};
  48     switch (rw) {
  49     case 'r':
  50         ev.events = EPOLLIN;
  51         break;
  52     case 'w':
  53         ev.events = EPOLLOUT;
  54         break;
  55     }
  56     ev.events |= EPOLLRDHUP | EPOLLPRI;
  57     ev.data.ptr = s;
  58
  59     return epoll_ctl(epfd, op, s->fd, &ev);
  60 }
  61
  62
  63 int
  64 socknext(Socket **s, int64 timeout)
  65 {
  66     int r;
  67     struct epoll_event ev = {.events=0};
  68
  69     r = epoll_wait(epfd, &ev, 1, (int)(timeout/1000000));
  70     if (r == -1 && errno != EINTR) {
  71         twarn("epoll_wait");
  72         exit(1);
  73     }
  74
  75     if (r > 0) {
  76         *s = ev.data.ptr;
  77         if (ev.events & (EPOLLHUP|EPOLLRDHUP)) {
  78             return 'h';
  79         } else if (ev.events & EPOLLIN) {
  80             return 'r';
  81         } else if (ev.events & EPOLLOUT) {
  82             return 'w';
  83         }
  84     }
  85     return 0;
  86 }