src/socketengines/socketengine_poll.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include "exitcodes.h"
  16 #include "socketengines/socketengine_poll.h"
  17 #include <poll.h>
  18 #include <ulimit.h>
  19
  20 PollEngine::PollEngine(InspIRCd* Instance) : SocketEngine(Instance)
  21 {
  22         // Poll requires no special setup (which is nice).
  23         CurrentSetSize = 0;
  24         MAX_DESCRIPTORS = 0;
  25
  26         ref = new EventHandler* [GetMaxFds()];
  27         events = new struct pollfd[GetMaxFds()];
  28
  29         memset(events, 0, GetMaxFds() * sizeof(struct pollfd));
  30         memset(ref, 0, GetMaxFds() * sizeof(EventHandler*));
  31 }
  32
  33 PollEngine::~PollEngine()
  34 {
  35         // No destruction required, either.
  36         delete[] ref;
  37         delete[] events;
  38 }
  39
  40 bool PollEngine::AddFd(EventHandler* eh)
  41 {
  42         int fd = eh->GetFd();
  43         if ((fd < 0) || (fd > GetMaxFds() - 1))
  44         {
  45                 ServerInstance->Logs->Log("SOCKET",DEBUG,"AddFd out of range: (fd: %d, max: %d)", fd, GetMaxFds());
  46                 return false;
  47         }
  48
  49         if (GetRemainingFds() <= 1)
  50         {
  51                 ServerInstance->Logs->Log("SOCKET",DEBUG,"No remaining FDs cannot add fd: %d", fd);
  52                 return false;
  53         }
  54
  55         if (ref[fd])
  56         {
  57                 ServerInstance->Logs->Log("SOCKET",DEBUG,"Attempt to add duplicate fd: %d", fd);
  58                 return false;
  59         }
  60
  61         ref[fd] = eh;
  62         events[fd].fd = fd;
  63         if (eh->Readable())
  64         {
  65                 events[fd].events = POLLIN;
  66         }
  67         else
  68         {
  69                 events[fd].events = POLLOUT;
  70         }
  71
  72         ServerInstance->Logs->Log("SOCKET", DEBUG,"New file descriptor: %d (%d)", fd, events[fd].events);
  73         CurrentSetSize++;
  74         return true;
  75 }
  76
  77 void PollEngine::WantWrite(EventHandler* eh)
  78 {
  79         events[eh->GetFd()].events = POLLIN | POLLOUT;
  80 }
  81
  82 bool PollEngine::DelFd(EventHandler* eh, bool force)
  83 {
  84         int fd = eh->GetFd();
  85         if ((fd < 0) || (fd > MAX_DESCRIPTORS))
  86         {
  87                 ServerInstance->Logs->Log("SOCKET", DEBUG, "DelFd out of range: (fd: %d, max: %d)", fd, GetMaxFds());
  88                 return false;
  89         }
  90
  91         events[fd].fd = -1;
  92         events[fd].events = 0;
  93
  94         CurrentSetSize--;
  95         ref[fd] = NULL;
  96
  97         ServerInstance->Logs->Log("SOCKET", DEBUG, "Remove file descriptor: %d", fd);
  98         return true;
  99 }
 100
 101 int PollEngine::GetMaxFds()
 102 {
 103         if (MAX_DESCRIPTORS)
 104                 return MAX_DESCRIPTORS;
 105
 106         int max = ulimit(4, 0);
 107         if (max > 0)
 108         {
 109                 MAX_DESCRIPTORS = max;
 110                 return max;
 111         }
 112         else
 113         {
 114                 ServerInstance->Logs->Log("SOCKET", DEFAULT, "ERROR: Can't determine maximum number of open sockets!");
 115                 printf("ERROR: Can't determine maximum number of open sockets!\n");
 116                 ServerInstance->Exit(EXIT_STATUS_SOCKETENGINE);
 117         }
 118         return 0;
 119 }
 120
 121 int PollEngine::GetRemainingFds()
 122 {
 123         return MAX_DESCRIPTORS - CurrentSetSize;
 124 }
 125
 126 int PollEngine::DispatchEvents()
 127 {
 128         int i = poll(events, GetMaxFds() - 1, 1000);
 129         int fd = 0;
 130         socklen_t codesize = sizeof(int);
 131         int errcode;
 132         int processed = 0;
 133
 134         if (i > 0)
 135         {
 136                 for (fd = 0; fd < GetMaxFds() - 1 && processed != i; fd++)
 137                 {
 138                         if (events[fd].revents)
 139                                 processed++;
 140
 141                         if (events[fd].revents & POLLHUP)
 142                         {
 143                                 if (ref[fd])
 144                                         ref[fd]->HandleEvent(EVENT_ERROR, 0);
 145                                 continue;
 146                         }
 147
 148                         if (events[fd].revents & POLLERR)
 149                         {
 150                                 // Get error number
 151                                 if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &errcode, &codesize) < 0)
 152                                         errcode = errno;
 153                                 if (ref[fd])
 154                                         ref[fd]->HandleEvent(EVENT_ERROR, errcode);
 155                                 continue;
 156                         }
 157
 158                         if (events[fd].revents & POLLOUT)
 159                         {
 160                                 // Switch to wanting read again
 161                                 // event handlers have to request to write again if they need it
 162                                 events[fd].events = POLLIN;
 163
 164
 165                                 if (ref[fd])
 166                                         ref[fd]->HandleEvent(EVENT_WRITE);
 167                         }
 168
 169                         if (events[fd].revents & POLLIN)
 170                         {
 171                                 if (ref[fd])
 172                                         ref[fd]->HandleEvent(EVENT_READ);
 173                         }
 174                 }
 175         }
 176
 177         return i;
 178 }
 179
 180 std::string PollEngine::GetName()
 181 {
 182         return "poll";
 183 }
 184