XlibAsync.c revision 61b2299d 
1/* $Xorg: XlibAsync.c,v 1.4 2001/02/09 02:03:38 xorgcvs Exp $ */
2/*
3
4Copyright 1992, 1998  The Open Group
5
6Permission to use, copy, modify, distribute, and sell this software and its
7documentation for any purpose is hereby granted without fee, provided that
8the above copyright notice appear in all copies and that both that
9copyright notice and this permission notice appear in supporting
10documentation.
11
12The above copyright notice and this permission notice shall be included
13in all copies or substantial portions of the Software.
14
15THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
16OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
19OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21OTHER DEALINGS IN THE SOFTWARE.
22
23Except as contained in this notice, the name of The Open Group shall
24not be used in advertising or otherwise to promote the sale, use or
25other dealings in this Software without prior written authorization
26from The Open Group.
27
28*/
29
30#define NEED_REPLIES
31#ifdef HAVE_CONFIG_H
32#include <config.h>
33#endif
34#include <X11/Xlibint.h>
35#include <X11/Xos.h>
36
37/*ARGSUSED*/
38Bool
39_XAsyncErrorHandler(
40    register Display *dpy,
41    register xReply *rep,
42    char *buf,
43    int len,
44    XPointer data)
45{
46    register _XAsyncErrorState *state;
47
48    state = (_XAsyncErrorState *)data;
49    if (rep->generic.type == X_Error &&
50	(!state->error_code ||
51	 rep->error.errorCode == state->error_code) &&
52	(!state->major_opcode ||
53	 rep->error.majorCode == state->major_opcode) &&
54	(!state->minor_opcode ||
55	 rep->error.minorCode == state->minor_opcode) &&
56	(!state->min_sequence_number ||
57	 (state->min_sequence_number <= dpy->last_request_read)) &&
58	(!state->max_sequence_number ||
59	 (state->max_sequence_number >= dpy->last_request_read))) {
60	state->last_error_received = rep->error.errorCode;
61	state->error_count++;
62	return True;
63    }
64    return False;
65}
66
67void _XDeqAsyncHandler(
68    Display *dpy,
69    register _XAsyncHandler *handler)
70{
71    register _XAsyncHandler **prev;
72    register _XAsyncHandler *async;
73
74    for (prev = &dpy->async_handlers;
75	 (async = *prev) && (async != handler);
76	 prev = &async->next)
77	;
78    if (async)
79	*prev = async->next;
80}
81
82char *
83_XGetAsyncReply(
84    register Display *dpy,
85    register char *replbuf,	/* data is read into this buffer */
86    register xReply *rep,	/* value passed to calling handler */
87    char *buf,			/* value passed to calling handler */
88    int len,			/* value passed to calling handler */
89    int extra,			/* extra words to read, ala _XReply */
90    Bool discard)		/* discard after extra?, ala _XReply */
91{
92    if (extra == 0) {
93	if (discard && (rep->generic.length << 2) > len)
94	    _XEatData (dpy, (rep->generic.length << 2) - len);
95	return (char *)rep;
96    }
97
98    if (extra <= rep->generic.length) {
99	int size = SIZEOF(xReply) + (extra << 2);
100	if (size > len) {
101	    memcpy(replbuf, buf, len);
102	    _XRead(dpy, replbuf + len, size - len);
103	    buf = replbuf;
104	    len = size;
105#ifdef MUSTCOPY
106	} else {
107	    memcpy(replbuf, buf, size);
108	    buf = replbuf;
109#endif
110	}
111
112	if (discard && rep->generic.length > extra &&
113	    (rep->generic.length << 2) > len)
114	    _XEatData (dpy, (rep->generic.length << 2) - len);
115
116	return buf;
117    }
118    /*
119     *if we get here, then extra > rep->generic.length--meaning we
120     * read a reply that's shorter than we expected.  This is an
121     * error,  but we still need to figure out how to handle it...
122     */
123    if ((rep->generic.length << 2) > len)
124	_XEatData (dpy, (rep->generic.length << 2) - len);
125    _XIOError (dpy);
126    return (char *)rep;
127}
128
129void
130_XGetAsyncData(
131    Display *dpy,
132    char *data,			/* data is read into this buffer */
133    char *buf,			/* value passed to calling handler */
134    int len,			/* value passed to calling handler */
135    int skip,			/* number of bytes already read in previous
136				   _XGetAsyncReply or _XGetAsyncData calls */
137    int datalen,		/* size of data buffer in bytes */
138    int discardtotal)		/* min. bytes to consume (after skip) */
139{
140    buf += skip;
141    len -= skip;
142    if (!data) {
143	if (datalen > len)
144	    _XEatData(dpy, datalen - len);
145    } else if (datalen <= len) {
146	memcpy(data, buf, datalen);
147    } else {
148	memcpy(data, buf, len);
149	_XRead(dpy, data + len, datalen - len);
150    }
151    if (discardtotal > len) {
152	if (datalen > len)
153	    len = datalen;
154	_XEatData(dpy, discardtotal - len);
155    }
156}
157