async.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

static HANDLE16 __ws_async_handle = 0xdead;

/* Generic async query struct. we use symbolic names for the different queries
 * for readability.
 */
typedef struct _async_query {
	HWND16		hWnd;
	UINT16		uMsg;
	LPCSTR		ptr1;
#define host_name	ptr1
#define host_addr	ptr1
#define serv_name	ptr1
#define proto_name	ptr1
	LPCSTR		ptr2;
#define serv_proto	ptr2
	int		int1;
#define host_len	int1
#define proto_number	int1
#define serv_port	int1
	int		int2;
#define host_type	int2
	SEGPTR		sbuf;
	INT16		sbuflen;

	HANDLE16	async_handle;
	int		flags;
	int		qt;
    char xbuf[1];
} async_query;


/****************************************************************************
 * The async query function.
 *
 * It is either called as a thread startup routine or directly. It has
 * to free the passed arg from the process heap and PostMessageA the async
 * result or the error code.
 *
 * FIXME:
 *	- errorhandling not verified.
 */
static DWORD WINAPI _async_queryfun(LPVOID arg) {
	async_query	*aq = (async_query*)arg;
	int		size = 0;
	WORD		fail = 0;
	char		*targetptr = (HB_WIN32(aq)?(char*)aq->sbuf:0/*(char*)MapSL(aq->sbuf)*/);

	switch (aq->flags & AQ_GETMASK) {
	case AQ_GETHOST: {
			struct hostent *he;
			char *copy_hostent = targetptr;
                        char buf[100];
                        if( !(aq->host_name)) {
                            aq->host_name = buf;
                            if( gethostname( buf, 100) == -1) {
                                fail = WSAENOBUFS; /* appropriate ? */
                                break;
                            }
                        }
			he = (aq->flags & AQ_NAME) ?
				gethostbyname(aq->host_name):
				gethostbyaddr(aq->host_addr,aq->host_len,aq->host_type);
                        if (!he) fail = WSAGetLastError();
			if (he) {
				size = WS_copy_he(copy_hostent,(char*)aq->sbuf,aq->sbuflen,he,aq->flags);
				if (size < 0) {
					fail = WSAENOBUFS;
					size = -size;
				}
			}
		}
		break;
	case AQ_GETPROTO: {
#if defined(HAVE_GETPROTOBYNAME) && defined(HAVE_GETPROTOBYNUMBER)
			struct protoent *pe;
			char *copy_protoent = targetptr;
			pe = (aq->flags & AQ_NAME)?
				getprotobyname(aq->proto_name) :
				getprotobynumber(aq->proto_number);
			if (pe) {
				size = WS_copy_pe(copy_protoent,(char*)aq->sbuf,aq->sbuflen,pe,aq->flags);
				if (size < 0) {
					fail = WSAENOBUFS;
					size = -size;
				}
			} else {
                            if (aq->flags & AQ_NAME)
                                MESSAGE("protocol %s not found; You might want to add "
                                        "this to /etc/protocols\n", debugstr_a(aq->proto_name) );
                            else
                                MESSAGE("protocol number %d not found; You might want to add "
                                        "this to /etc/protocols\n", aq->proto_number );
                            fail = WSANO_DATA;
			}
#else
                        fail = WSANO_DATA;
#endif
		}
		break;
	case AQ_GETSERV: {
			struct servent	*se;
			char *copy_servent = targetptr;
			se = (aq->flags & AQ_NAME)?
				getservbyname(aq->serv_name,aq->serv_proto) :
#ifdef HAVE_GETSERVBYPORT
				getservbyport(aq->serv_port,aq->serv_proto);
#else
                                NULL;
#endif
			if (se) {
				size = WS_copy_se(copy_servent,(char*)aq->sbuf,aq->sbuflen,se,aq->flags);
				if (size < 0) {
					fail = WSAENOBUFS;
					size = -size;
				}
			} else {
                            if (aq->flags & AQ_NAME)
                                MESSAGE("service %s protocol %s not found; You might want to add "
                                        "this to /etc/services\n", debugstr_a(aq->serv_name) ,
                                        aq->serv_proto ? debugstr_a(aq->serv_proto ):"*");
                            else
                                MESSAGE("service on port %d protocol %s not found; You might want to add "
                                        "this to /etc/services\n", aq->serv_port,
                                        aq->serv_proto ? debugstr_a(aq->serv_proto ):"*");
                            fail = WSANO_DATA;
			}
		}
		break;
	}
	PostMessageA(HWND_32(aq->hWnd),aq->uMsg,(WPARAM) aq->async_handle,size|(fail<<16));
	HeapFree(GetProcessHeap(),0,arg);
	return 0;
}

/****************************************************************************
 * The main async help function.
 *
 * It either starts a thread or just calls the function directly for platforms
 * with no thread support. This relies on the fact that PostMessage() does
 * not actually call the windowproc before the function returns.
 */
static HANDLE16	__WSAsyncDBQuery(
	HWND hWnd, UINT uMsg,INT int1,LPCSTR ptr1, INT int2, LPCSTR ptr2,
	void *sbuf, INT sbuflen, UINT flags
)
{
        async_query*	aq;
	char*		pto;
	LPCSTR		pfm;
	int		xbuflen = 0;

	/* allocate buffer to copy protocol- and service name to */
	/* note: this is done in the calling thread so we can return */
	/* a decent error code if the Alloc fails */

	switch (flags & AQ_MASKPTR1) {
	case 0:							break;
	case AQ_COPYPTR1:	xbuflen += int1;		break;
	case AQ_DUPLOWPTR1:	xbuflen += strlen(ptr1) + 1;	break;
	}

	switch (flags & AQ_MASKPTR2) {
	case 0:							break;
	case AQ_COPYPTR2:	xbuflen += int2;		break;
	case AQ_DUPLOWPTR2:	xbuflen += strlen(ptr2) + 1;	break;
	}

	if(!(aq = HeapAlloc(GetProcessHeap(),0,sizeof(async_query) + xbuflen))) {
	        SetLastError(WSAEWOULDBLOCK); /* insufficient resources */
		return 0;
	}

	pto = aq->xbuf;
	if (ptr1) switch (flags & AQ_MASKPTR1) {
	case 0:											break;
	case AQ_COPYPTR1:   memcpy(pto, ptr1, int1); ptr1 = pto; pto += int1; 			break;
	case AQ_DUPLOWPTR1: pfm = ptr1; ptr1 = pto; do *pto++ = tolower(*pfm); while (*pfm++);	break;
	}
	if (ptr2) switch (flags & AQ_MASKPTR2) {
	case 0:											break;
	case AQ_COPYPTR2:   memcpy(pto, ptr2, int2); ptr2 = pto; pto += int2;			break;
	case AQ_DUPLOWPTR2: pfm = ptr2; ptr2 = pto; do *pto++ = tolower(*pfm); while (*pfm++);	break;
	}

	aq->hWnd	= HWND_16(hWnd);
	aq->uMsg	= uMsg;
	aq->int1	= int1;
	aq->ptr1	= ptr1;
	aq->int2	= int2;
	aq->ptr2	= ptr2;
	/* avoid async_handle = 0 */
	aq->async_handle = (++__ws_async_handle ? __ws_async_handle : ++__ws_async_handle);
	aq->flags	= flags;
	aq->sbuf	= (SEGPTR)sbuf;
	aq->sbuflen	= sbuflen;

#if 1
	if (CreateThread(NULL,0,_async_queryfun,aq,0,NULL) == INVALID_HANDLE_VALUE)
#endif
		_async_queryfun(aq);
	return __ws_async_handle;
}


/***********************************************************************
 *       WSAAsyncGetHostByAddr	(WINSOCK.102)
 */
HANDLE16 WINAPI WSAAsyncGetHostByAddr16(HWND16 hWnd, UINT16 uMsg, LPCSTR addr,
                               INT16 len, INT16 type, SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %04x, addr %08x[%i]\n",
	       hWnd, uMsg, (unsigned)addr , len );
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,len,addr,type,NULL,
				(void*)sbuf,buflen,
				AQ_NUMBER|AQ_COPYPTR1|AQ_WIN16|AQ_GETHOST);
}

/***********************************************************************
 *       WSAAsyncGetHostByAddr        (WS2_32.102)
 */
HANDLE WINAPI WSAAsyncGetHostByAddr(HWND hWnd, UINT uMsg, LPCSTR addr,
                               INT len, INT type, LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %04x, addr %08x[%i]\n",
	       hWnd, uMsg, (unsigned)addr , len );
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,len,addr,type,NULL,sbuf,buflen,
				AQ_NUMBER|AQ_COPYPTR1|AQ_WIN32|AQ_GETHOST));
}

/***********************************************************************
 *       WSAAsyncGetHostByName	(WINSOCK.103)
 */
HANDLE16 WINAPI WSAAsyncGetHostByName16(HWND16 hWnd, UINT16 uMsg, LPCSTR name,
                                      SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %04x, host %s, buffer %i\n",
	      hWnd, uMsg, (name)?name:"<null>", (int)buflen );
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,0,name,0,NULL,
				(void*)sbuf,buflen,
				AQ_NAME|AQ_DUPLOWPTR1|AQ_WIN16|AQ_GETHOST);
}

/***********************************************************************
 *       WSAAsyncGetHostByName	(WS2_32.103)
 */
HANDLE WINAPI WSAAsyncGetHostByName(HWND hWnd, UINT uMsg, LPCSTR name,
					LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %08x, host %s, buffer %i\n",
	       hWnd, uMsg, (name)?name:"<null>", (int)buflen );
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,0,name,0,NULL,sbuf,buflen,
				AQ_NAME|AQ_DUPLOWPTR1|AQ_WIN32|AQ_GETHOST));
}

/***********************************************************************
 *       WSAAsyncGetProtoByName	(WINSOCK.105)
 */
HANDLE16 WINAPI WSAAsyncGetProtoByName16(HWND16 hWnd, UINT16 uMsg, LPCSTR name,
                                         SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %08x, protocol %s\n",
	       hWnd, uMsg, (name)?name:"<null>" );
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,0,name,0,NULL,
				(void*)sbuf,buflen,
				AQ_NAME|AQ_DUPLOWPTR1|AQ_WIN16|AQ_GETPROTO);
}

/***********************************************************************
 *       WSAAsyncGetProtoByName       (WS2_32.105)
 */
HANDLE WINAPI WSAAsyncGetProtoByName(HWND hWnd, UINT uMsg, LPCSTR name,
                                         LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %08x, protocol %s\n",
	       hWnd, uMsg, (name)?name:"<null>" );
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,0,name,0,NULL,sbuf,buflen,
				AQ_NAME|AQ_DUPLOWPTR1|AQ_WIN32|AQ_GETPROTO));
}


/***********************************************************************
 *       WSAAsyncGetProtoByNumber	(WINSOCK.104)
 */
HANDLE16 WINAPI WSAAsyncGetProtoByNumber16(HWND16 hWnd,UINT16 uMsg,INT16 number,
                                           SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %04x, num %i\n", hWnd, uMsg, number );
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,number,NULL,0,NULL,
				(void*)sbuf,buflen,
				AQ_GETPROTO|AQ_NUMBER|AQ_WIN16);
}

/***********************************************************************
 *       WSAAsyncGetProtoByNumber     (WS2_32.104)
 */
HANDLE WINAPI WSAAsyncGetProtoByNumber(HWND hWnd, UINT uMsg, INT number,
                                           LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %04x, num %i\n", hWnd, uMsg, number );
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,number,NULL,0,NULL,sbuf,buflen,
				AQ_GETPROTO|AQ_NUMBER|AQ_WIN32));
}

/***********************************************************************
 *       WSAAsyncGetServByName	(WINSOCK.107)
 */
HANDLE16 WINAPI WSAAsyncGetServByName16(HWND16 hWnd, UINT16 uMsg, LPCSTR name,
                                        LPCSTR proto, SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %04x, name %s, proto %s\n",
	       hWnd, uMsg, (name)?name:"<null>", (proto)?proto:"<null>");
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,0,name,0,proto,
				(void*)sbuf,buflen,
				AQ_GETSERV|AQ_NAME|AQ_DUPLOWPTR1|AQ_DUPLOWPTR2|AQ_WIN16);
}

/***********************************************************************
 *       WSAAsyncGetServByName        (WS2_32.107)
 */
HANDLE WINAPI WSAAsyncGetServByName(HWND hWnd, UINT uMsg, LPCSTR name,
                                        LPCSTR proto, LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %04x, name %s, proto %s\n",
	       hWnd, uMsg, (name)?name:"<null>", (proto)?proto:"<null>");
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,0,name,0,proto,sbuf,buflen,
				AQ_GETSERV|AQ_NAME|AQ_DUPLOWPTR1|AQ_DUPLOWPTR2|AQ_WIN32));
}

/***********************************************************************
 *       WSAAsyncGetServByPort	(WINSOCK.106)
 */
HANDLE16 WINAPI WSAAsyncGetServByPort16(HWND16 hWnd, UINT16 uMsg, INT16 port,
                                        LPCSTR proto, SEGPTR sbuf, INT16 buflen)
{
	TRACE("hwnd %04x, msg %04x, port %i, proto %s\n",
	       hWnd, uMsg, port, (proto)?proto:"<null>" );
	return __WSAsyncDBQuery(HWND_32(hWnd),uMsg,port,NULL,0,proto,
				(void*)sbuf,buflen,
				AQ_GETSERV|AQ_NUMBER|AQ_DUPLOWPTR2|AQ_WIN16);
}

/***********************************************************************
 *       WSAAsyncGetServByPort        (WS2_32.106)
 */
HANDLE WINAPI WSAAsyncGetServByPort(HWND hWnd, UINT uMsg, INT port,
                                        LPCSTR proto, LPSTR sbuf, INT buflen)
{
	TRACE("hwnd %p, msg %04x, port %i, proto %s\n",
	       hWnd, uMsg, port, (proto)?proto:"<null>" );
	return WSA_H32( __WSAsyncDBQuery(hWnd,uMsg,port,NULL,0,proto,sbuf,buflen,
				AQ_GETSERV|AQ_NUMBER|AQ_DUPLOWPTR2|AQ_WIN32));
}