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#if defined(SCALANATIVE_COMPILE_ALWAYS) ||                                     \
    defined(__SCALANATIVE_POSIX_SYS_SELECT)
#include 
#include 
#include 
#include 

#ifdef _WIN32
#pragma comment(lib, "ws2_32.lib")
#include 
typedef long int suseconds_t;
#else
#include 
#endif

#if (FD_SETSIZE > 1024)
// Cross checking code is a mixed blessing. It can generate both
// false positives and get out of sync. Such code should, in general,
// be avoided.
//
// Here there is a magic compile time constant that _is_ going to grow,
// sometime after tomorrow. That change will cause a mismatch
// between this C code and the scala static type declaration and
// undesired things will happen.
//
// For one example, FD_ZERO below will try to clear memory beyond the end
// of the smaller fd_set allocated by the scala code.
//
// Being robust to such a change is well worth the code smell of this
// large block comment. Miserere mei peccatoris.
//
#error("Probable size mismatch with static fd_set type in select.scala ")
#endif

#define FDBITS (8 * sizeof(long))

struct scalanative_timeval {
    time_t tv_sec;
    suseconds_t tv_usec;
};

struct scalanative_fd_set {
    long fd_bits[FD_SETSIZE / FDBITS];
};

int scalanative_fd_setsize() { return FD_SETSIZE; }

void convert_scalanative_timeval(struct scalanative_timeval *in,
                                 struct timeval *out) {
    out->tv_sec = in->tv_sec;
    out->tv_usec = in->tv_usec;
}

void scalanative_fd_zero(struct scalanative_fd_set *set) {
    FD_ZERO((fd_set *)set);
}

void scalanative_fd_clr(int fd, struct scalanative_fd_set *set) {
    FD_CLR(fd, (fd_set *)set);
}

void scalanative_fd_set(int fd, struct scalanative_fd_set *set) {
    FD_SET(fd, (fd_set *)set);
}

int scalanative_fd_isset(int fd, struct scalanative_fd_set *set) {
    return FD_ISSET(fd, (fd_set *)set);
}

//  pselect() is straight call through, so no declaration here.

int scalanative_select(int nfds, struct scalanative_fd_set *readfds,
                       struct scalanative_fd_set *writefds,
                       struct scalanative_fd_set *exceptfds,
                       struct scalanative_timeval *scalanative_timeout) {
    fd_set *rfds = (fd_set *)readfds;
    fd_set *wfds = (fd_set *)writefds;
    fd_set *efds = (fd_set *)exceptfds;

    int status;
    if (scalanative_timeout != NULL) {
        struct timeval timeout;
        convert_scalanative_timeval(scalanative_timeout, &timeout);
        status = select(nfds, rfds, wfds, efds, &timeout);
    } else {
        status = select(nfds, rfds, wfds, efds, NULL);
    }

    return status;
}
#endif