src/hd/rholo4.c

/* Copyright (c) 1997 Silicon Graphics, Inc. */

#ifndef lint
static char SCCSid[] = "$SunId$ SGI";
#endif

/*
 * Holodeck display process communication
 */

#include "rholo.h"
#include "rhdisp.h"
#include <sys/uio.h>

#ifndef HDSUF
#define HDSUF   ".hdisp"
#endif

static int      inp_flags;
static int      dpd[3];
static int      pipesiz;


disp_open(dname)                /* open the named display driver */
char    *dname;
{
        char    dpath[128], *com[2];
        int     i;

#ifdef DEVPATH
        sprintf(dpath, "%s/%s%s", DEVPATH, dname, HDSUF);
#else
        sprintf(dpath, "dev/%s%s", dname, HDSUF);
#endif
        com[0] = dpath; com[1] = NULL;
        pipesiz = open_process(dpd, com);
        if (pipesiz <= 0)
                error(USER, "cannot start display process");
        inp_flags = 0;
                                /* write out hologram grids */
        for (i = 0; hdlist[i] != NULL; i++)
                disp_result(DS_ADDHOLO, sizeof(HDGRID), (char *)hdlist[i]);
}


disp_packet(p)                  /* display a packet */
register PACKHEAD       *p;
{
        disp_result(DS_BUNDLE, packsiz(p->nr), (char *)p);
}


disp_check(block)               /* check display process */
int     block;
{
        MSGHEAD msg;
        int     n;
        char    *buf = NULL;

        if (pipesiz <= 0)
                return(-1);
                                        /* check read blocking */
        if (block != (inp_flags == 0)) {
                inp_flags = block ? 0 : FNONBLK;
                if (fcntl(dpd[0], F_SETFL, inp_flags) < 0)
                        goto fcntlerr;
        }
                                        /* read message header */
        n = read(dpd[0], (char *)&msg, sizeof(MSGHEAD));
        if (n != sizeof(MSGHEAD)) {
                if (n >= 0)
                        error(USER, "display process died");
                if (errno != EAGAIN & errno != EINTR)
                        goto readerr;
                return(2);              /* acceptable failure */
        }
        if (msg.nbytes) {               /* get the message body */
                buf = (char *)malloc(msg.nbytes);
                if (buf == NULL)
                        error(SYSTEM, "out of memory in disp_check");
                if (fcntl(dpd[0], F_SETFL, inp_flags=0) < 0)
                        goto fcntlerr;
                if (readbuf(dpd[0], buf, msg.nbytes) != msg.nbytes)
                        goto readerr;
        }
        switch (msg.type) {             /* take appropriate action */
        case DR_BUNDLE:
                if (msg.nbytes != sizeof(PACKHEAD))
                        error(INTERNAL, "bad DR_BUNDLE from display process");
                bundle_set(BS_ADD, (PACKHEAD *)buf, 1);
                break;
        case DR_NEWSET:
                if (msg.nbytes % sizeof(PACKHEAD))
                        error(INTERNAL, "bad DR_NEWSET from display process");
                disp_result(DS_STARTIMM, 0, NULL);
                bundle_set(BS_NEW, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
                disp_result(DS_ENDIMM, 0, NULL);
                break;
        case DR_ADDSET:
                if (msg.nbytes % sizeof(PACKHEAD))
                        error(INTERNAL, "bad DR_ADDSET from display process");
                disp_result(DS_STARTIMM, 0, NULL);
                bundle_set(BS_ADD, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
                disp_result(DS_ENDIMM, 0, NULL);
                break;
        case DR_DELSET:
                if (msg.nbytes % sizeof(PACKHEAD))
                        error(INTERNAL, "bad DR_DELSET from display process");
                bundle_set(BS_DEL, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
                break;
        case DR_ATTEN:
                if (msg.nbytes)
                        error(INTERNAL, "bad DR_ATTEN from display process");
                                        /* send acknowledgement */
                disp_result(DS_ACKNOW, 0, NULL);
                return(disp_check(1));  /* block on following request */
        case DR_SHUTDOWN:
                if (msg.nbytes)
                        error(INTERNAL, "bad DR_SHUTDOWN from display process");
                return(0);              /* zero return signals shutdown */
        default:
                error(INTERNAL, "unrecognized request from display process");
        }
        if (msg.nbytes)                 /* clean up */
                free(buf);
        return(1);                      /* normal return value */
fcntlerr:
        error(SYSTEM, "cannot change display blocking mode");
readerr:
        error(SYSTEM, "error reading from display process");
}


int
disp_close()                    /* close our display process */
{
        int     rval;

        if (pipesiz <= 0)
                return(-1);
        disp_result(DS_SHUTDOWN, 0, NULL);
        pipesiz = 0;
        return(close_process(dpd));
}


disp_result(type, nbytes, p)    /* send result message to display process */
int     type, nbytes;
char    *p;
{
        struct iovec    iov[2];
        MSGHEAD msg;
        int     n;

        if (pipesiz <= 0)
                return;
        msg.type = type;
        msg.nbytes = nbytes;
        if (nbytes == 0 || sizeof(MSGHEAD)+nbytes > pipesiz) {
                do
                        n = write(dpd[1], (char *)&msg, sizeof(MSGHEAD));
                while (n < 0 && errno == EINTR);
                if (n != sizeof(MSGHEAD))
                        goto writerr;
                if (nbytes > 0 && writebuf(dpd[1], p, nbytes) != nbytes)
                        goto writerr;
                return;
        }
        iov[0].iov_base = (char *)&msg;
        iov[0].iov_len = sizeof(MSGHEAD);
        iov[1].iov_base = p;
        iov[1].iov_len = nbytes;
        do
                n = writev(dpd[1], iov, 2);
        while (n < 0 && errno == EINTR);
        if (n == sizeof(MSGHEAD)+nbytes)
                return;
writerr:
        error(SYSTEM, "write error in disp_result");
}
Revision:	3.4
Committed:	Thu Nov 6 16:12:41 1997 UTC (28 years ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 3.3:	+4 -8 lines
Log Message:	changed disp_packet to take PACKHEAD* r.t. PACKET*
#	User	Rev	Content
1	gregl	3.1	/* Copyright (c) 1997 Silicon Graphics, Inc. */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ SGI";
5			#endif
6
7			/*
8			* Holodeck display process communication
9			*/
10
11			#include "rholo.h"
12			#include "rhdisp.h"
13	gregl	3.2	#include <sys/uio.h>
14	gregl	3.1
15	gregl	3.2	#ifndef HDSUF
16			#define HDSUF ".hdisp"
17			#endif
18	gregl	3.1
19	gregl	3.2	static int inp_flags;
20			static int dpd[3];
21			static int pipesiz;
22
23
24			disp_open(dname) /* open the named display driver */
25	gregl	3.1	char *dname;
26			{
27	gregl	3.2	char dpath[128], *com[2];
28			int i;
29
30			#ifdef DEVPATH
31			sprintf(dpath, "%s/%s%s", DEVPATH, dname, HDSUF);
32			#else
33			sprintf(dpath, "dev/%s%s", dname, HDSUF);
34			#endif
35			com[0] = dpath; com[1] = NULL;
36			pipesiz = open_process(dpd, com);
37			if (pipesiz <= 0)
38			error(USER, "cannot start display process");
39			inp_flags = 0;
40			/* write out hologram grids */
41			for (i = 0; hdlist[i] != NULL; i++)
42			disp_result(DS_ADDHOLO, sizeof(HDGRID), (char *)hdlist[i]);
43	gregl	3.1	}
44
45
46	gregl	3.2	disp_packet(p) /* display a packet */
47	gregl	3.4	register PACKHEAD *p;
48	gregl	3.2	{
49	gregl	3.4	disp_result(DS_BUNDLE, packsiz(p->nr), (char *)p);
50	gregl	3.2	}
51
52
53	gregl	3.1	disp_check(block) /* check display process */
54			int block;
55			{
56	gregl	3.2	MSGHEAD msg;
57			int n;
58			char *buf = NULL;
59
60			if (pipesiz <= 0)
61			return(-1);
62	gregl	3.3	/* check read blocking */
63	gregl	3.2	if (block != (inp_flags == 0)) {
64			inp_flags = block ? 0 : FNONBLK;
65			if (fcntl(dpd[0], F_SETFL, inp_flags) < 0)
66			goto fcntlerr;
67			}
68			/* read message header */
69			n = read(dpd[0], (char *)&msg, sizeof(MSGHEAD));
70			if (n != sizeof(MSGHEAD)) {
71			if (n >= 0)
72			error(USER, "display process died");
73			if (errno != EAGAIN & errno != EINTR)
74			goto readerr;
75	gregl	3.3	return(2); /* acceptable failure */
76	gregl	3.2	}
77			if (msg.nbytes) { /* get the message body */
78			buf = (char *)malloc(msg.nbytes);
79			if (buf == NULL)
80			error(SYSTEM, "out of memory in disp_check");
81			if (fcntl(dpd[0], F_SETFL, inp_flags=0) < 0)
82			goto fcntlerr;
83			if (readbuf(dpd[0], buf, msg.nbytes) != msg.nbytes)
84			goto readerr;
85			}
86			switch (msg.type) { /* take appropriate action */
87			case DR_BUNDLE:
88			if (msg.nbytes != sizeof(PACKHEAD))
89			error(INTERNAL, "bad DR_BUNDLE from display process");
90			bundle_set(BS_ADD, (PACKHEAD *)buf, 1);
91			break;
92			case DR_NEWSET:
93			if (msg.nbytes % sizeof(PACKHEAD))
94			error(INTERNAL, "bad DR_NEWSET from display process");
95			disp_result(DS_STARTIMM, 0, NULL);
96			bundle_set(BS_NEW, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
97			disp_result(DS_ENDIMM, 0, NULL);
98			break;
99			case DR_ADDSET:
100			if (msg.nbytes % sizeof(PACKHEAD))
101			error(INTERNAL, "bad DR_ADDSET from display process");
102			disp_result(DS_STARTIMM, 0, NULL);
103			bundle_set(BS_ADD, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
104			disp_result(DS_ENDIMM, 0, NULL);
105			break;
106			case DR_DELSET:
107			if (msg.nbytes % sizeof(PACKHEAD))
108			error(INTERNAL, "bad DR_DELSET from display process");
109			bundle_set(BS_DEL, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
110			break;
111			case DR_ATTEN:
112			if (msg.nbytes)
113			error(INTERNAL, "bad DR_ATTEN from display process");
114			/* send acknowledgement */
115			disp_result(DS_ACKNOW, 0, NULL);
116	gregl	3.3	return(disp_check(1)); /* block on following request */
117	gregl	3.2	case DR_SHUTDOWN:
118			if (msg.nbytes)
119			error(INTERNAL, "bad DR_SHUTDOWN from display process");
120			return(0); /* zero return signals shutdown */
121			default:
122			error(INTERNAL, "unrecognized request from display process");
123			}
124	gregl	3.3	if (msg.nbytes) /* clean up */
125	gregl	3.2	free(buf);
126			return(1); /* normal return value */
127			fcntlerr:
128			error(SYSTEM, "cannot change display blocking mode");
129			readerr:
130			error(SYSTEM, "error reading from display process");
131	gregl	3.1	}
132
133
134	gregl	3.2	int
135			disp_close() /* close our display process */
136	gregl	3.1	{
137	gregl	3.2	int rval;
138
139			if (pipesiz <= 0)
140			return(-1);
141			disp_result(DS_SHUTDOWN, 0, NULL);
142			pipesiz = 0;
143			return(close_process(dpd));
144			}
145
146
147			disp_result(type, nbytes, p) /* send result message to display process */
148			int type, nbytes;
149			char *p;
150			{
151			struct iovec iov[2];
152			MSGHEAD msg;
153			int n;
154
155	gregl	3.3	if (pipesiz <= 0)
156			return;
157	gregl	3.2	msg.type = type;
158			msg.nbytes = nbytes;
159			if (nbytes == 0 \|\| sizeof(MSGHEAD)+nbytes > pipesiz) {
160	gregl	3.3	do
161			n = write(dpd[1], (char *)&msg, sizeof(MSGHEAD));
162			while (n < 0 && errno == EINTR);
163	gregl	3.2	if (n != sizeof(MSGHEAD))
164			goto writerr;
165	gregl	3.4	if (nbytes > 0 && writebuf(dpd[1], p, nbytes) != nbytes)
166			goto writerr;
167	gregl	3.2	return;
168			}
169			iov[0].iov_base = (char *)&msg;
170			iov[0].iov_len = sizeof(MSGHEAD);
171			iov[1].iov_base = p;
172			iov[1].iov_len = nbytes;
173	gregl	3.3	do
174			n = writev(dpd[1], iov, 2);
175			while (n < 0 && errno == EINTR);
176			if (n == sizeof(MSGHEAD)+nbytes)
177	gregl	3.2	return;
178			writerr:
179			error(SYSTEM, "write error in disp_result");
180	gregl	3.1	}