sendrecv.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

/* These are just demos of how the code for the other OSes.
 * I haven't tested these, but they're right in terms of interface.
 * I just wanted to see what types of vars would be required from other OSes. 
 */

#elif defined(__FreeBSD__)

/* Release 3.1 or greater */
apr_status_t apr_sendfile(apr_socket_t * sock, apr_file_t * file,
        		apr_hdtr_t * hdtr, apr_off_t * offset, apr_size_t * len,
        		apr_int32_t flags)
{
    off_t nbytes = 0;
    int rv, i;
    struct sf_hdtr headerstruct;
    size_t bytes_to_send = *len;

    if (!hdtr) {
        hdtr = &no_hdtr;
    }

    /* Ignore flags for now. */
    flags = 0;

    /* On FreeBSD, the number of bytes to send must include the length of
     * the headers.  Don't look at the man page for this :(  Instead, look
     * at the the logic in src/sys/kern/uipc_syscalls::sendfile().
     */
    
    for (i = 0; i < hdtr->numheaders; i++) {
        bytes_to_send += hdtr->headers[i].iov_len;
    }

    headerstruct.headers = hdtr->headers;
    headerstruct.hdr_cnt = hdtr->numheaders;
    headerstruct.trailers = hdtr->trailers;
    headerstruct.trl_cnt = hdtr->numtrailers;

    /* FreeBSD can send the headers/footers as part of the system call */
    if (sock->timeout >= 0) {
        /* On FreeBSD, it is possible for the first call to sendfile to
         * get EAGAIN, but still send some data.  This means that we cannot
         * call sendfile and then check for EAGAIN, and then wait and call
         * sendfile again.  If we do that, then we are likely to send the
         * first chunk of data twice, once in the first call and once in the
         * second.  If we are using a timed write, then we check to make sure
         * we can send data before trying to send it.
         */
        apr_status_t arv = wait_for_io_or_timeout(sock, 0);
        if (arv != APR_SUCCESS) {
            *len = 0;
            return arv;
        }
    }

    do {
        if (bytes_to_send) {
            /* We won't dare call sendfile() if we don't have
             * header or file bytes to send because bytes_to_send == 0
             * means send the whole file.
             */
            rv = sendfile(file->filedes, /* file to be sent */
                          sock->socketdes, /* socket */
                          *offset,       /* where in the file to start */
                          bytes_to_send, /* number of bytes to send */
                          &headerstruct, /* Headers/footers */
                          &nbytes,       /* number of bytes written */
                          flags);        /* undefined, set to 0 */
        }
        else {
            /* just trailer bytes... use writev()
             */
            rv = writev(sock->socketdes,
                        hdtr->trailers,
                        hdtr->numtrailers);
            if (rv > 0) {
                nbytes = rv;
                rv = 0;
            }
            else {
                nbytes = 0;
            }
        }
    } while (rv == -1 && errno == EINTR);

    (*len) = nbytes;
    if (rv == -1 && (errno != EAGAIN || (errno == EAGAIN && sock->timeout < 0))) {
        return errno;
    }
    return APR_SUCCESS;
}

#elif defined(__hpux) || defined(__hpux__)

/* HP cc in ANSI mode defines __hpux; gcc defines __hpux__ */

/* HP-UX Version 10.30 or greater
 * (no worries, because we only get here if autoconfiguration found sendfile)
 */

/* ssize_t sendfile(int s, int fd, off_t offset, size_t nbytes,
 *                  const struct iovec *hdtrl, int flags);
 *
 * nbytes is the number of bytes to send just from the file; as with FreeBSD, 
 * if nbytes == 0, the rest of the file (from offset) is sent
 */

apr_status_t apr_sendfile(apr_socket_t *sock, apr_file_t *file,
			  apr_hdtr_t *hdtr, apr_off_t *offset, apr_size_t *len,
			  apr_int32_t flags)
{
    int i;
    ssize_t rc;
    size_t nbytes = *len, headerlen, trailerlen;
    struct iovec hdtrarray[2];
    char *headerbuf, *trailerbuf;

    if (!hdtr) {
        hdtr = &no_hdtr;
    }

    /* Ignore flags for now. */
    flags = 0;

    /* HP-UX can only send one header iovec and one footer iovec; try to
     * only allocate storage to combine input iovecs when we really have to
     */

    switch(hdtr->numheaders) {
    case 0:
        hdtrarray[0].iov_base = NULL;
        hdtrarray[0].iov_len = 0;
        break;
    case 1:
        hdtrarray[0] = hdtr->headers[0];
        break;
    default:
        headerlen = 0;
        for (i = 0; i < hdtr->numheaders; i++) {
            headerlen += hdtr->headers[i].iov_len;
        }  

        /* XXX:  BUHHH? wow, what a memory leak! */
        headerbuf = hdtrarray[0].iov_base = apr_palloc(sock->cntxt, headerlen);
        hdtrarray[0].iov_len = headerlen;

        for (i = 0; i < hdtr->numheaders; i++) {
            memcpy(headerbuf, hdtr->headers[i].iov_base,
                   hdtr->headers[i].iov_len);
            headerbuf += hdtr->headers[i].iov_len;
        }
    }

    switch(hdtr->numtrailers) {
    case 0:
        hdtrarray[1].iov_base = NULL;
        hdtrarray[1].iov_len = 0;
        break;
    case 1:
        hdtrarray[1] = hdtr->trailers[0];
        break;
    default:
        trailerlen = 0;
        for (i = 0; i < hdtr->numtrailers; i++) {
            trailerlen += hdtr->trailers[i].iov_len;
        }

        /* XXX:  BUHHH? wow, what a memory leak! */
        trailerbuf = hdtrarray[1].iov_base = apr_palloc(sock->cntxt, trailerlen);
        hdtrarray[1].iov_len = trailerlen;

        for (i = 0; i < hdtr->numtrailers; i++) {
            memcpy(trailerbuf, hdtr->trailers[i].iov_base,
                   hdtr->trailers[i].iov_len);
            trailerbuf += hdtr->trailers[i].iov_len;
        }
    }

    do {
        if (nbytes) {       /* any bytes to send from the file? */
            rc = sendfile(sock->socketdes,      /* socket  */
                          file->filedes,        /* file descriptor to send */
                          *offset,              /* where in the file to start */
                          nbytes,               /* number of bytes to send from file */
                          hdtrarray,            /* Headers/footers */
                          flags);               /* undefined, set to 0 */
        }
        else {              /* we can't call sendfile() with no bytes to send from the file */
            rc = writev(sock->socketdes, hdtrarray, 2);
        }
    } while (rc == -1 && errno == EINTR);

    if (rc == -1 && 
        (errno == EAGAIN || errno == EWOULDBLOCK) && 
        sock->timeout > 0) {
        apr_status_t arv = wait_for_io_or_timeout(sock, 0);

        if (arv != APR_SUCCESS) {
            *len = 0;
            return arv;
        }
        else {
            do {
                if (nbytes) {
                    rc = sendfile(sock->socketdes,    /* socket  */
                                  file->filedes,      /* file descriptor to send */
                                  *offset,            /* where in the file to start */
                                  nbytes,             /* number of bytes to send from file */
                                  hdtrarray,          /* Headers/footers */
                                  flags);             /* undefined, set to 0 */
                }
                else {      /* we can't call sendfile() with no bytes to send from the file */
                    rc = writev(sock->socketdes, hdtrarray, 2);
                }
            } while (rc == -1 && errno == EINTR);
        }
    }

    if (rc == -1) {
	*len = 0;
        return errno;
    }

    /* Set len to the number of bytes written */
    *len = rc;
    return APR_SUCCESS;
}
#elif defined(_AIX) || defined(__MVS__)
/* AIX and OS/390 have the same send_file() interface.
 *
 * subtle differences:
 *   AIX doesn't update the file ptr but OS/390 does
 *
 * availability (correctly determined by autoconf):
 *
 * AIX -  version 4.3.2 with APAR IX85388, or version 4.3.3 and above
 * OS/390 - V2R7 and above
 */
apr_status_t apr_sendfile(apr_socket_t * sock, apr_file_t * file,
                        apr_hdtr_t * hdtr, apr_off_t * offset, apr_size_t * len,
                        apr_int32_t flags)
{
    int i, ptr, rv = 0;
    void * hbuf=NULL, * tbuf=NULL;
    apr_status_t arv;
    struct sf_parms parms;

    if (!hdtr) {
        hdtr = &no_hdtr;
    }

    /* Ignore flags for now. */
    flags = 0;

    /* AIX can also send the headers/footers as part of the system call */
    parms.header_length = 0;
    if (hdtr && hdtr->numheaders) {
        if (hdtr->numheaders == 1) {
            parms.header_data = hdtr->headers[0].iov_base;
            parms.header_length = hdtr->headers[0].iov_len;
        }
        else {
            for (i = 0; i < hdtr->numheaders; i++) {
                parms.header_length += hdtr->headers[i].iov_len;
            }
#if 0
            /* Keepalives make apr_palloc a bad idea */
            hbuf = malloc(parms.header_length);
#else
            /* but headers are small, so maybe we can hold on to the
             * memory for the life of the socket...
             */
            hbuf = apr_palloc(sock->cntxt, parms.header_length);
#endif
            ptr = 0;
            for (i = 0; i < hdtr->numheaders; i++) {
                memcpy((char *)hbuf + ptr, hdtr->headers[i].iov_base,
                       hdtr->headers[i].iov_len);
                ptr += hdtr->headers[i].iov_len;
            }
            parms.header_data = hbuf;
        }
    }
    else parms.header_data = NULL;
    parms.trailer_length = 0;
    if (hdtr && hdtr->numtrailers) {
        if (hdtr->numtrailers == 1) {
            parms.trailer_data = hdtr->trailers[0].iov_base;
            parms.trailer_length = hdtr->trailers[0].iov_len;
        }
        else {
            for (i = 0; i < hdtr->numtrailers; i++) {
                parms.trailer_length += hdtr->trailers[i].iov_len;
            }
#if 0
            /* Keepalives make apr_palloc a bad idea */
            tbuf = malloc(parms.trailer_length);
#else
            tbuf = apr_palloc(sock->cntxt, parms.trailer_length);
#endif
            ptr = 0;
            for (i = 0; i < hdtr->numtrailers; i++) {
                memcpy((char *)tbuf + ptr, hdtr->trailers[i].iov_base,
                       hdtr->trailers[i].iov_len);
                ptr += hdtr->trailers[i].iov_len;
            }
            parms.trailer_data = tbuf;
        }
    }
    else parms.trailer_data = NULL;

    /* Whew! Headers and trailers set up. Now for the file data */

    parms.file_descriptor = file->filedes;
    parms.file_offset = *offset;
    parms.file_bytes = *len;

    /* O.K. All set up now. Let's go to town */

    do {
        rv = send_file(&(sock->socketdes), /* socket */
                       &(parms),           /* all data */
                       flags);             /* flags */
    } while (rv == -1 && errno == EINTR);

    if (rv == -1 &&
        (errno == EAGAIN || errno == EWOULDBLOCK) &&
        sock->timeout > 0) {
        arv = wait_for_io_or_timeout(sock, 0);
        if (arv != APR_SUCCESS) {
            *len = 0;
            return arv;
        }
        else {
            do {
                rv = send_file(&(sock->socketdes), /* socket */
                               &(parms),           /* all data */
                               flags);             /* flags */
            } while (rv == -1 && errno == EINTR);
        }
    }

    (*len) = parms.bytes_sent;

#if 0
    /* Clean up after ourselves */
    if(hbuf) free(hbuf);
    if(tbuf) free(tbuf);
#endif

    if (rv == -1) {
        return errno;
    }
    return APR_SUCCESS;
}
#elif defined(__osf__) && defined (__alpha)
/* Tru64's sendfile implementation doesn't work, and we need to make sure that
 * we don't use it until it is fixed.  If it is used as it is now, it will
 * hang the machine and the only way to fix it is a reboot.
 */
#else
#error APR has detected sendfile on your system, but nobody has written a
#error version of it for APR yet.  To get past this, either write apr_sendfile
#error or change APR_HAS_SENDFILE in apr.h to 0. 
#endif /* __linux__, __FreeBSD__, __HPUX__, _AIX, __MVS__, Tru64/OSF1 */
#endif /* APR_HAS_SENDFILE */

#if !APR_HAS_SENDFILE
/* currently, exports.c includes a reference to apr_sendfile() even if 
 * apr_sendfile() doesn't work on the platform;
 * this dummy version is just to get exports.c to compile/link
 */
apr_status_t apr_sendfile(apr_socket_t *sock, apr_file_t *file,
                          apr_hdtr_t *hdtr, apr_off_t *offset, apr_size_t *len,
                          apr_int32_t flags); /* avoid warning for no proto */

apr_status_t apr_sendfile(apr_socket_t *sock, apr_file_t *file,
                          apr_hdtr_t *hdtr, apr_off_t *offset, apr_size_t *len,
                          apr_int32_t flags)
{
    return APR_ENOTIMPL;
}
#endif