| /* |
| Simple DirectMedia Layer |
| Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org> |
| |
| This software is provided 'as-is', without any express or implied |
| warranty. In no event will the authors be held liable for any damages |
| arising from the use of this software. |
| |
| Permission is granted to anyone to use this software for any purpose, |
| including commercial applications, and to alter it and redistribute it |
| freely, subject to the following restrictions: |
| |
| 1. The origin of this software must not be misrepresented; you must not |
| claim that you wrote the original software. If you use this software |
| in a product, an acknowledgment in the product documentation would be |
| appreciated but is not required. |
| 2. Altered source versions must be plainly marked as such, and must not be |
| misrepresented as being the original software. |
| 3. This notice may not be removed or altered from any source distribution. |
| */ |
| |
| #include "../../SDL_internal.h" |
| |
| #include "SDL_poll.h" |
| |
| #ifdef HAVE_POLL |
| #include <poll.h> |
| #else |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| #endif |
| #include <errno.h> |
| |
| |
| int |
| SDL_IOReady(int fd, SDL_bool forWrite, int timeoutMS) |
| { |
| int result; |
| |
| /* Note: We don't bother to account for elapsed time if we get EINTR */ |
| do |
| { |
| #ifdef HAVE_POLL |
| struct pollfd info; |
| |
| info.fd = fd; |
| if (forWrite) { |
| info.events = POLLOUT; |
| } else { |
| info.events = POLLIN | POLLPRI; |
| } |
| result = poll(&info, 1, timeoutMS); |
| #else |
| fd_set rfdset, *rfdp = NULL; |
| fd_set wfdset, *wfdp = NULL; |
| struct timeval tv, *tvp = NULL; |
| |
| /* If this assert triggers we'll corrupt memory here */ |
| SDL_assert(fd >= 0 && fd < FD_SETSIZE); |
| |
| if (forWrite) { |
| FD_ZERO(&wfdset); |
| FD_SET(fd, &wfdset); |
| wfdp = &wfdset; |
| } else { |
| FD_ZERO(&rfdset); |
| FD_SET(fd, &rfdset); |
| rfdp = &rfdset; |
| } |
| |
| if (timeoutMS >= 0) { |
| tv.tv_sec = timeoutMS / 1000; |
| tv.tv_usec = (timeoutMS % 1000) * 1000; |
| tvp = &tv; |
| } |
| |
| result = select(fd + 1, rfdp, wfdp, NULL, tvp); |
| #endif /* HAVE_POLL */ |
| |
| } while ( result < 0 && errno == EINTR ); |
| |
| return result; |
| } |
| |
| /* vi: set ts=4 sw=4 expandtab: */ |