httpd.c

嵌入式操作系统ECOS的网络开发包

}

/* ================================================================= */
/* Initialization thread
 *
 * Optionally delay for a time before getting the network
 * running. Then create and bind the server socket and put it into
 * listen mode. Spawn any further server threads, then enter server
 * mode.
 */

static void cyg_httpd_init(cyg_addrword_t arg)
{
    int i;
    int err = 0;

    /* Delay for a configurable length of time to give the application
     * a chance to get going, or even complete, without interference
     * from the HTTPD.
     */
    if( CYGNUM_HTTPD_SERVER_DELAY > 0 )
    {
        cyg_thread_delay( CYGNUM_HTTPD_SERVER_DELAY );
    }
    
    server_address.sin_family = AF_INET;
    server_address.sin_len = sizeof(server_address);
    server_address.sin_addr.s_addr = INADDR_ANY;
    server_address.sin_port = htons(CYGNUM_HTTPD_SERVER_PORT);

    /* Get the network going. This is benign if the application has
     * already done this.
     */
    init_all_network_interfaces();

    /* Create and bind the server socket.
     */
    server_socket = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP );
    CYG_ASSERT( server_socket > 0, "Socket create failed");

    err = bind( server_socket, (struct sockaddr *)&server_address,
                sizeof(server_address) );
    CYG_ASSERT( err == 0, "bind() returned error");

    err = listen( server_socket, SOMAXCONN );
    CYG_ASSERT( err == 0, "listen() returned error" );

    /* If we are configured to have more than one server thread,
     * create them now.
     */
    for( i = 1; i < CYGNUM_HTTPD_THREAD_COUNT; i++ )
    {
        cyg_thread_create( CYGNUM_HTTPD_THREAD_PRIORITY,
                           cyg_httpd_server,
                           0,
                           "HTTPD",
                           &httpd_stacks[i][0],
                           sizeof(httpd_stacks[i]),
                           &httpd_thread[i],
                           &httpd_thread_object[i]
            );
    
        cyg_thread_resume( httpd_thread[i] );
    }

    /* Now go be a server ourself.
     */
    cyg_httpd_server(arg);
}

/* ================================================================= */
/* System initializer
 *
 * This is called from the static constructor in init.cxx. It spawns
 * the main server thread and makes it ready to run.
 */

__externC void cyg_httpd_startup(void)
{
    cyg_thread_create( CYGNUM_HTTPD_THREAD_PRIORITY,
                       cyg_httpd_init,
                       0,
                       "HTTPD",
                       &httpd_stacks[0][0],
                       sizeof(httpd_stacks[0]),
                       &httpd_thread[0],
                       &httpd_thread_object[0]
        );
    
    cyg_thread_resume( httpd_thread[0] );
}

/* ================================================================= */
/*  HTTP protocol handling
 *
 * cyg_http_start() generates an HTTP header with the given content
 * type and, if non-zero, length.
 * cyg_http_finish() just adds a couple of newlines for luck and
 * flushes the stream.
 */

__externC void cyg_http_start( FILE *client, char *content_type,
                               int content_length )
{
    fputs( "HTTP/1.1 200 OK\n"
           "Server: " CYGDAT_HTTPD_SERVER_ID,
           client );

    if( content_type != NULL )
        fprintf( client,"Content-type: %s\n", content_type );

    if( content_length != 0 )
        fprintf( client, "Content-length: %d\n", content_length );

    fputs( "Connection: close\n"
           "\n",
           client );    
}

__externC void cyg_http_finish( FILE *client )
{
    fputs( "\n\n", client );
    fflush( client );
}
    

/* ================================================================= */
/* HTML tag generation
 *
 * These functions generate standard HTML begin and end tags. By using
 * these rather than direct printf()s we help to reduce the number of
 * distinct strings present in the executable.
 */

__externC void cyg_html_tag_begin( FILE *client, char *tag, char *attr )
{
    char *pad = "";

    if( attr == NULL )
        attr = pad;
    else if( attr[0] != 0 )
        pad = " ";

    fprintf(client, "<%s%s%s>\n",tag,pad,attr);
}

__externC void cyg_html_tag_end( FILE *client, char *tag )
{
    fprintf( client, "<%s%s%s>\n","/",tag,"");
}

/* ================================================================= */
/* Parse form request data
 *
 * Given a form response string, we parse it into an argv/environment
 * style array of "name=value" strings. We also convert any '+'
 * separators back into spaces.
 *
 * TODO: also translate any %xx escape sequences back into real
 * characters.
 */

__externC void cyg_formdata_parse( char *data, char *list[], int size )
{
    char *p = data;
    int i = 0;

    list[i] = p;
    
    while( *p != 0 && i < size-1 )
    {
        if( *p == '&' )
        {
            *p++ = 0;
            list[++i] = p;
            continue;
        }
        if( *p == '+' )
            *p = ' ';
        p++;
    }

    list[++i] = 0;
}

/* ----------------------------------------------------------------- */
/* Search for a form response value
 *
 * Search a form response list generated by cyg_formdata_parse() for
 * the named element. If it is found a pointer to the value part is
 * returned. If it is not found a NULL pointer is returned.
 */

__externC char *cyg_formlist_find( char *list[], char *name )
{
    while( *list != 0 )
    {
        char *p = *list;
        char *q = name;

        while( *p == *q )
            p++, q++;

        if( *q == 0 && *p == '=' )
            return p+1;
        
        list++;
    }

    return 0;
}

/* ================================================================= */
/* Predefined page handlers
 */

/* ----------------------------------------------------------------- */
/* Send an HTML page from a single string
 *
 * This just sends the string passed as the argument with an HTTP
 * header that describes it as HTML. This is useful for sending
 * straightforward static web content.
 */

__externC cyg_bool cyg_httpd_send_html( FILE *client, char *filename,
                                        char *request, void *arg )
{
    html_begin( client );
    
    fwrite( arg, 1, strlen((char *)arg), client );

    html_end( client );

    return true;
}

/* ----------------------------------------------------------------- */
/* Send arbitrary data
 *
 * This takes a pointer to a cyg_httpd_data structure as the argument
 * and sends the data therein after a header that uses the content
 * type and size from the structure. This is useful for non-HTML data
 * such a images.
 */

__externC cyg_bool cyg_httpd_send_data( FILE *client, char *filename,
                                        char *request, void *arg )
{
    cyg_httpd_data *data = (cyg_httpd_data *)arg;

    cyg_http_start( client, data->content_type, data->content_length );
    
    fwrite( data->data, 1, data->content_length, client );

    return true;
}

/* ----------------------------------------------------------------- */
/* end of httpd.c                                                    */