
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>



ssize_t
ngx_udp_wsasend(ngx_connection_t *c, u_char *buf, size_t size)
{
    int           n;
    u_long        sent;
    ngx_err_t     err;
    ngx_event_t  *wev;
    WSABUF        wsabuf;

    wev = c->write;

    if (!wev->ready) {
        return NGX_AGAIN;
    }

    /*
     * WSABUF must be 4-byte aligned otherwise
     * WSASend() will return undocumented WSAEINVAL error.
     */

    wsabuf.buf = (char *) buf;
    wsabuf.len = size;

    sent = 0;

   n = WSASendTo(c->fd,&wsabuf,1,&sent,0,c->sockaddr, c->socklen,NULL,NULL);

    ngx_log_debug4(NGX_LOG_DEBUG_EVENT, c->log, 0,
                   "WSASend: fd:%d, %d, %ul of %uz", c->fd, n, sent, size);

    if (n == 0) {
        if (sent < size) {
            wev->ready = 0;
        }

        c->sent += sent;

        return sent;
    }

    err = ngx_socket_errno;

    if (err == WSAEWOULDBLOCK) {
        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, err, "WSASend() not ready");
        wev->ready = 0;
        return NGX_AGAIN;
    }

    wev->error = 1;
    ngx_connection_error(c, err, "WSASend() failed");

    return NGX_ERROR;
}
