SRecv.c

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#include "syshdrs.h"
 
#ifndef NO_SIGNALS
extern volatile Sjmp_buf gNetTimeoutJmp;
extern volatile Sjmp_buf gPipeJmp;
#endif
 
#ifndef NO_SIGNALS
 
int
SRecv(int sfd, char *const buf0, size_t size, int fl, int tlen, int retry)
{
    int nread;
    volatile int nleft;
    char *volatile buf = buf0;
    int tleft;
    vsio_sigproc_t sigalrm, sigpipe;
    time_t done, now;
 
    if (SSetjmp(gNetTimeoutJmp) != 0) {
        alarm(0);
        (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
        (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
        nread = size - nleft;
        if ((nread > 0) && (retry == kFullBufferNotRequired))
            return (nread);
        errno = ETIMEDOUT;
        return (kTimeoutErr);
    }
 
    if (SSetjmp(gPipeJmp) != 0) {
        alarm(0);
        (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
        (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
        nread = size - nleft;
        if ((nread > 0) && (retry == kFullBufferNotRequired))
            return (nread);
        errno = EPIPE;
        return (kBrokenPipeErr);
    }
 
    sigalrm = (vsio_sigproc_t) SSignal(SIGALRM, SIOHandler);
    sigpipe = (vsio_sigproc_t) SSignal(SIGPIPE, SIOHandler);
    errno = 0;
 
    nleft = (int) size;
    time(&now);
    done = now + tlen;
    forever {
        tleft = (int) (done - now);
        if (tleft < 1) {
            nread = size - nleft;
            if ((nread == 0) || (retry == kFullBufferRequired)) {
                nread = kTimeoutErr;
                errno = ETIMEDOUT;
            }
            goto done;
        }
        (void) alarm((unsigned int) tleft);
        nread = recv(sfd, (char *) buf, nleft, fl);
        (void) alarm(0);
        if (nread <= 0) {
            if (nread == 0) {
                /* EOF */
                if (retry == kFullBufferRequiredExceptLast)
                    nread = size - nleft;
                goto done;
            } else if (errno != EINTR) {
                nread = size - nleft;
                if (nread == 0)
                    nread = -1;
                goto done;
            } else {
                errno = 0;
                nread = 0;
                /* Try again. */
            }
        }
        nleft -= nread;
        if ((nleft <= 0) || ((retry == 0) && (nleft != (int) size)))
            break;
        buf += nread;
        time(&now);
    }
    nread = size - nleft;
 
done:
    (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
    (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
 
    return (nread);
}   /* SRecv */
 
#else
 
int
SRecv(int sfd, char *const buf0, size_t size, int fl, int tlen, int retry)
{
    int nread;
    int nleft;
    char *buf = buf0;
    int tleft;
    time_t done, now;
    fd_set ss;
    struct timeval tv;
    int result;
 
    errno = 0;
 
    nleft = (int) size;
    time(&now);
    done = now + tlen;
    forever {
        tleft = (int) (done - now);
        if (tleft < 1) {
            nread = size - nleft;
            if ((nread == 0) || (retry == kFullBufferRequired)) {
                nread = kTimeoutErr;
                errno = ETIMEDOUT;
                SETWSATIMEOUTERR
            }
            goto done;
        }
 
        forever {
            errno = 0;
            FD_ZERO(&ss);
            FD_SET(sfd, &ss);
            tv.tv_sec = tlen;
            tv.tv_usec = 0;
            result = select(sfd + 1, SELECT_TYPE_ARG234 &ss, NULL, NULL, SELECT_TYPE_ARG5 &tv);
            if (result == 1) {
                /* ready */
                break;
            } else if (result == 0) {
                /* timeout */
                nread = size - nleft;
                if ((nread > 0) && (retry == kFullBufferNotRequired))
                    return (nread);
                errno = ETIMEDOUT;
                SETWSATIMEOUTERR
                return (kTimeoutErr);
            } else if (errno != EINTR) {
                return (-1);
            }
        }
 
#if defined(WIN32) || defined(_WINDOWS)
        nread = recv(sfd, (char *) buf, nleft, fl);
#else
        nread = recv(sfd, (char *) buf, nleft, fl);
#endif
 
        if (nread <= 0) {
            if (nread == 0) {
                /* EOF */
                if (retry == kFullBufferRequiredExceptLast)
                    nread = size - nleft;
                goto done;
            } else if (errno != EINTR) {
                nread = size - nleft;
                if (nread == 0)
                    nread = -1;
                goto done;
            } else {
                errno = 0;
                nread = 0;
                /* Try again. */
            }
        }
        nleft -= nread;
        if ((nleft <= 0) || ((retry == 0) && (nleft != (int) size)))
            break;
        buf += nread;
        time(&now);
    }
    nread = size - nleft;
 
done:
    return (nread);
}   /* SRecv */
 
#endif