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#include "mypoll.h"
#define MYPOLL_READ (1<<1)
#define MYPOLL_WRITE (1<<2)
int mypoll(pollfd_struct* fds, int nfds, int timeout) {
fd_set rset, wset, *r=0, *w=0;
int i, ret, maxfd=-1;
struct timeval tv = {0}, *t = 0;
for(i=0; i<nfds; ++i) {
if(fds[i].events & MYPOLL_READ) r = &rset;
if(fds[i].events & MYPOLL_WRITE) w = &wset;
if(r && w) break;
}
if(r) FD_ZERO(r);
if(w) FD_ZERO(w);
for(i=0; i<nfds; ++i) {
if(fds[i].fd > maxfd) maxfd = fds[i].fd;
if(fds[i].events & MYPOLL_READ) FD_SET(fds[i].fd, r);
if(fds[i].events & MYPOLL_WRITE) FD_SET(fds[i].fd, w);
}
if(timeout >= 0) t = &tv;
if(timeout > 0) tv.tv_sec = timeout;
ret = select(maxfd+1, r, w, 0, t);
switch(ret) {
case -1:
case 0:
return ret;
}
for(i=0; i<nfds; ++i) {
fds[i].revents = 0;
if(r && FD_ISSET(fds[i].fd, r)) fds[i].revents |= MYPOLL_READ;
if(w && FD_ISSET(fds[i].fd, w)) fds[i].revents |= MYPOLL_WRITE;
}
return ret;
}
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