git.m6w6.name Git - awesomized/libmemcached/blob - poll/poll.c

   1 /* LibMemcached
   2  * Copyright (C) 2010 Brian Aker, Trond Norbye
   3  * All rights reserved.
   4  *
   5  * Use and distribution licensed under the BSD license.  See
   6  * the COPYING file in the parent directory for full text.
   7  *
   8  * Summary: Implementation of poll by using select
   9  *
  10  */
  11 #include "mem_config.h"
  12
  13 #if defined(WIN32) || defined(__MINGW32__)
  14 # include <winsock2.h>
  15 # include <ws2tcpip.h>
  16 #endif
  17
  18 #include <sys/time.h>
  19 #include <strings.h>
  20
  21 #include "poll/poll.h"
  22
  23 int poll(struct pollfd fds[], nfds_t nfds, int tmo)
  24 {
  25   fd_set readfds, writefds, errorfds;
  26   FD_ZERO(&readfds);
  27   FD_ZERO(&writefds);
  28   FD_ZERO(&errorfds);
  29
  30   int maxfd= 0;
  31
  32   for (nfds_t x= 0; x < nfds; ++x)
  33   {
  34     if (fds[x].events & (POLLIN | POLLOUT))
  35     {
  36 #ifndef WIN32
  37       if (fds[x].fd > maxfd)
  38       {
  39         maxfd= fds[x].fd;
  40       }
  41 #endif
  42       if (fds[x].events & POLLIN)
  43       {
  44         FD_SET(fds[x].fd, &readfds);
  45       }
  46       if (fds[x].events & POLLOUT)
  47       {
  48         FD_SET(fds[x].fd, &writefds);
  49       }
  50     }
  51   }
  52
  53   struct timeval timeout= { .tv_sec = tmo / 1000,
  54                             .tv_usec= (tmo % 1000) * 1000 };
  55   struct timeval *tp= &timeout;
  56   if (tmo == -1)
  57   {
  58     tp= NULL;
  59   }
  60   int ret= select(maxfd + 1, &readfds, &writefds, &errorfds, tp);
  61   if (ret <= 0)
  62   {
  63     return ret;
  64   }
  65
  66   /* Iterate through all of them because I need to clear the revent map */
  67   for (nfds_t x= 0; x < nfds; ++x)
  68   {
  69     fds[x].revents= 0;
  70     if (FD_ISSET(fds[x].fd, &readfds))
  71     {
  72       fds[x].revents |= POLLIN;
  73     }
  74     if (FD_ISSET(fds[x].fd, &writefds))
  75     {
  76       fds[x].revents |= POLLOUT;
  77     }
  78     if (FD_ISSET(fds[x].fd, &errorfds))
  79     {
  80       fds[x].revents |= POLLERR;
  81     }
  82   }
  83
  84    return ret;
  85 }