1 

     2 #include "Reactor.hh"

     3 

     4 

     5 NetworkReactor::NetworkReactor (void) :

     6     sockets()

     7 {

     8 

     9 }

    10 

    11 void NetworkReactor::poll (timeval *timeout) {

    12     // start counting the maximum fd from -1, so that select is given nfds=0 if our list is empty

    13     int fd_max = 0;

    14 

    15     // zero our fdsets

    16     fd_set read, write;

    17     FD_ZERO(&read);

    18     FD_ZERO(&write);

    19 

    20     // inspect our sockets

    21     for (std::list<NetworkSocket*>::iterator it = sockets.begin(); it != sockets.end(); it++) {

    22         NetworkSocket *socket = *it;

    23     

    24         // ask socket what events it wants

    25         NetworkPollMask mask = socket->get_poll();

    26 

    27         // set read/write

    28         if (mask) {

    29             // socket file descriptor...

    30             int fd = socket->get_socket();

    31 

    32             // ignore invalid FDs

    33             if (fd < 0)

    34                 continue;

    35             

    36             // update fd_max?

    37             if (fd > fd_max)

    38                 fd_max = fd;

    39             

    40             // read...

    41             if (mask & POLL_READ)

    42                 FD_SET(socket->get_socket(), &read);

    43             

    44             // write...

    45             if (mask & POLL_WRITE)

    46                 FD_SET(socket->get_socket(), &write);

    47         }

    48     }

    49 

    50     // run select

    51     int ret;

    52     

    53     // we never care about except

    54     // pass NULL fdsets if they are empty

    55     if ((ret = select(

    56             fd_max + 1, 

    57             fd_max ? &read : NULL, 

    58             fd_max ? &write : NULL, 

    59             NULL, 

    60             timeout

    61     )) < 0)

    62         throw NetworkReactorError("select");

    63     

    64     // ignore if we just timed out

    65     if (ret == 0)

    66         return;

    67 

    68     // notify up to <ret> socket-events

    69     for (std::list<NetworkSocket*>::iterator it = sockets.begin(); it != sockets.end() && ret > 0; it++) {

    70         NetworkSocket *socket = *it;

    71 

    72         // socket file descriptor...

    73         int fd = socket->get_socket();

    74             

    75         // ignore invalid FDs

    76         if (fd < 0)

    77             continue;

    78         

    79         // mask of events detected

    80         NetworkPollMask mask = 0;

    81         

    82         // detect read

    83         if (FD_ISSET(fd, &read)) {

    84             mask |= POLL_READ;

    85             ret--;

    86         }

    87 

    88         // detect write

    89         if (FD_ISSET(fd, &write)) {

    90             mask |= POLL_WRITE;

    91             ret--;

    92         }

    93         

    94         // notify?

    95         if (mask)

    96             socket->notify(mask);

    97     }

    98 }

    99 

   100 // the global reactor

   101 static NetworkReactor g_reactor;

   102 NetworkReactor *NetworkReactor::current = &g_reactor;

   103