libslp_findsrvtypes.c

SLP协议在linux下的实现。此版本为1.2.1版。官方网站为www.openslp.org

        goto FINISHED;
    }

    /*----------------------------------------------------------------*/
    /* Build a buffer containing the fixed portion of the SRVTYPERQST */
    /*----------------------------------------------------------------*/
    /* naming authority */
    if(strcmp(handle->params.findsrvtypes.namingauth, "*") == 0)
    {
        ToUINT16(curpos,0xffff); /* 0xffff indicates all service types */
        curpos += 2;
        bufsize--;      /* '*' is not put on the wire */
    }
    else
    {
        ToUINT16(curpos,handle->params.findsrvtypes.namingauthlen);
        curpos += 2;
        memcpy(curpos,
               handle->params.findsrvtypes.namingauth,
               handle->params.findsrvtypes.namingauthlen);
        curpos += handle->params.findsrvtypes.namingauthlen;
    }
    /* scope list */
    ToUINT16(curpos,handle->params.findsrvtypes.scopelistlen);
    curpos = curpos + 2;
    memcpy(curpos,
           handle->params.findsrvtypes.scopelist,
           handle->params.findsrvtypes.scopelistlen);
    curpos = curpos + handle->params.findsrvtypes.scopelistlen;


    /*--------------------------*/
    /* Call the RqstRply engine */
    /*--------------------------*/
    do
    {
        #ifndef UNICAST_NOT_SUPPORTED
        if ( handle->dounicast == 1 ) 
	{
            void *cookie = (PSLPHandleInfo) handle;
	    result = NetworkUcastRqstRply(handle,
                                          buf,
                                          SLP_FUNCT_SRVTYPERQST,
                                          bufsize,
					  ProcessSrvTypeRplyCallback,
					  cookie);
	    break;
        }
	else
	#endif
	sock = NetworkConnectToDA(handle,
                                  handle->params.findsrvtypes.scopelist,
                                  handle->params.findsrvtypes.scopelistlen,
                                  &peeraddr);
        if(sock == -1)
        {
            /* use multicast as a last resort */
            #ifndef MI_NOT_SUPPORTED
            result = NetworkMcastRqstRply(handle,
                                          buf,
					  SLP_FUNCT_SRVTYPERQST,
					  bufsize,
                                          ProcessSrvTypeRplyCallback,
					  NULL);
            #else
            result = NetworkMcastRqstRply(handle->langtag,
                                          buf,
                                          SLP_FUNCT_SRVTYPERQST,
                                          bufsize,
                                          ProcessSrvTypeRplyCallback,
                                          handle);
            #endif /* MI_NOT_SUPPORTED */
            break;
        }

        result = NetworkRqstRply(sock,
                                 &peeraddr,
                                 handle->langtag,
                                 0,
                                 buf,
                                 SLP_FUNCT_SRVTYPERQST,
                                 bufsize,
                                 ProcessSrvTypeRplyCallback,
                                 handle);
        if(result)
        {
            NetworkDisconnectDA(handle);
        }

    }while(result == SLP_NETWORK_ERROR);


    FINISHED:
    if(buf) xfree(buf);

    return result;
}                                   

#ifdef ENABLE_ASYNC_API
/*-------------------------------------------------------------------------*/ 
SLPError AsyncProcessSrvTypeRqst(PSLPHandleInfo handle)
/*-------------------------------------------------------------------------*/
{
    SLPError result = ProcessSrvTypeRqst(handle);
    xfree((void*)handle->params.findsrvtypes.namingauth);
    xfree((void*)handle->params.findsrvtypes.scopelist);
    handle->inUse = SLP_FALSE;
    return result;
}
#endif

/*=========================================================================*/
SLPError SLPAPI SLPFindSrvTypes(SLPHandle    hSLP,
                         const char  *pcNamingAuthority,
                         const char  *pcScopeList,
                         SLPSrvTypeCallback callback,
                         void *pvCookie)
/*                                                                         */
/* Issue the query for service types on the language specific SLPHandle    */
/* and return the results through the callback.  The parameters determine  */
/* the results                                                             */
/*                                                                         */
/* hSLP              The language specific SLPHandle on which to search    */
/*                   for service types.                                    */
/*                                                                         */
/* pcNamingAuthority The Naming Authority string for which service types   */
/*                   for which service types are returned                  */
/*                                                                         */
/* pcScopeList      A pointer to a char containing comma separated list of */
/*                  scope names.  Pass in the NULL or the empty string ""  */
/*                  to find services in all the scopes the local host is   */
/*                  configured query.                                      */
/*                                                                         */
/* callback         A callback function through which the results of the   */
/*                  operation are reported. May not be NULL                */
/*                                                                         */
/* pvCookie         Memory passed to the callback code from the client.    */
/*                  May be NULL.                                           */
/*                                                                         */
/* Returns:         If an error occurs in starting the operation, one of   */
/*                  the SLPError codes is returned.                        */
/*                                                                         */
/*=========================================================================*/
{
    PSLPHandleInfo      handle;
    SLPError            result;

    /*------------------------------*/
    /* check for invalid parameters */
    /*------------------------------*/
    if(hSLP == 0 ||
       *(unsigned int*)hSLP != SLP_HANDLE_SIG ||
       !pcNamingAuthority ||
       strcmp(pcNamingAuthority, "IANA") == 0 ||
       callback == 0)
    {
        return SLP_PARAMETER_BAD;
    }

    /*-----------------------------------------*/
    /* cast the SLPHandle into a SLPHandleInfo */
    /*-----------------------------------------*/
    handle = (PSLPHandleInfo)hSLP; 

    /*-----------------------------------------*/
    /* Check to see if the handle is in use    */
    /*-----------------------------------------*/
    if(handle->inUse == SLP_TRUE)
    {
        return SLP_HANDLE_IN_USE;
    }
    handle->inUse = SLP_TRUE;

    /*-------------------------------------------*/
    /* Set the handle up to reference parameters */
    /*-------------------------------------------*/
    handle->params.findsrvtypes.namingauthlen = strlen(pcNamingAuthority);
    handle->params.findsrvtypes.namingauth = pcNamingAuthority;
    if(pcScopeList && *pcScopeList)
    {
        handle->params.findsrvtypes.scopelist = pcScopeList;
    }
    else
    {
        handle->params.findsrvtypes.scopelist =
        SLPGetProperty("net.slp.useScopes"); 
    }
    handle->params.findsrvtypes.scopelistlen =
    strlen(handle->params.findsrvtypes.scopelist); 
    handle->params.findsrvtypes.callback     = callback;
    handle->params.findsrvtypes.cookie       = pvCookie; 

    /*----------------------------------------------*/
    /* Check to see if we should be async or sync   */
    /*----------------------------------------------*/
#ifdef ENABLE_ASYNC_API
    if(handle->isAsync)
    {
        /* COPY all the referenced parameters */
        handle->params.findsrvtypes.namingauth = xstrdup(handle->params.findsrvtypes.namingauth);
        handle->params.findsrvtypes.scopelist = xstrdup(handle->params.findsrvtypes.scopelist);

        /* make sure strdups did not fail */
        if(handle->params.findsrvtypes.namingauth &&
           handle->params.findsrvtypes.scopelist)
        {
            result = ThreadCreate((ThreadStartProc)AsyncProcessSrvTypeRqst,handle);
        }
        else
        {
            result = SLP_MEMORY_ALLOC_FAILED;    
        }

        if(result)
        {
            if(handle->params.findsrvtypes.namingauth) xfree((void*)handle->params.findsrvtypes.namingauth);
            if(handle->params.findsrvtypes.scopelist) xfree((void*)handle->params.findsrvtypes.scopelist);
            handle->inUse = SLP_FALSE;
        }
    }
    else
#endif /*ifdef ENABLE_ASYNC_API*/
    {
        /* Leave all parameters REFERENCED */

        result = ProcessSrvTypeRqst(handle);

        handle->inUse = SLP_FALSE;
    }

    return result;
}