WINDOWS socket cannot listen more than 63 sockets

Description

WINDOWS socket should not have any limitation on the number of sockets

Code version identification

158239bab1ae0

Current behavior

Windows 'select' C function can only listen to 64 elements, thus limiting the actual possible range of sockets connections.

See https://learn.microsoft.com/en-us/windows/win32/winsock/maximum-number-of-sockets-supported-2

Security impact

None (availability issue)

Implementation

(Proposition): Use this updated API instead of select:

WSAPOLLFD fds[1024];
fds[0].fd = socket_fd;
fds[0].events = POLLIN | POLLOUT;

int result = WSAPoll(fds, 1, timeout_ms);

Other options:

  • WSAPoll (scalable, very close to select API (less rework)
  • WSAEventSelect() + WSAWaitForMultipleEvents() (adapted to range ~ 100-200 sockets)
  • WSARecv (overlapped IO) (Much more complex)
Edited by Jérémie Chabod