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;
static FILE     *dpout;


disp_open(dname)                /* open the named display driver */
char    *dname;
{
        char    dpath[128], *com[3];
        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] = froot; com[2] = NULL;
        pipesiz = open_process(dpd, com);
        if (pipesiz <= 0)
                error(USER, "cannot start display process");
        if ((dpout = fdopen(dup(dpd[1]), "w")) == NULL)
                error(SYSTEM, "cannot associate FILE with display pipe");
        inp_flags = 0;
                                /* write out hologram grids */
        for (i = 0; hdlist[i] != NULL; i++)
                disp_result(DS_ADDHOLO, sizeof(HDGRID), (char *)hdlist[i]);
        disp_flush();
}


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);
                                        /* flush display output */
        disp_flush();
                                        /* 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);
                disp_flush();
                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);
                disp_flush();
                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);
        fclose(dpout);
        dpout = NULL;
        pipesiz = 0;
        return(close_process(dpd));
}


disp_result(type, nbytes, p)    /* queue result message to display process */
int     type, nbytes;
char    *p;
{
        MSGHEAD msg;

        msg.type = type;
        msg.nbytes = nbytes;
        fwrite((char *)&msg, sizeof(MSGHEAD), 1, dpout);
        if (nbytes > 0)
                fwrite(p, 1, nbytes, dpout);
}


disp_flush()                    /* flush output to display */
{
        if (fflush(dpout) < 0)
                error(SYSTEM, "error writing to the display process");
}
Revision:	3.5
Committed:	Mon Nov 10 18:07:15 1997 UTC (26 years, 5 months ago) by gregl
Content type:	text/plain
Branch:	MAIN
Changes since 3.4:	+23 -28 lines
Log Message:	changed from unbuffered to buffered output to display process added name to display program arguments
#	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	gregl	3.5	static FILE *dpout;
23	gregl	3.2
24
25			disp_open(dname) /* open the named display driver */
26	gregl	3.1	char *dname;
27			{
28	gregl	3.5	char dpath[128], *com[3];
29	gregl	3.2	int i;
30
31			#ifdef DEVPATH
32			sprintf(dpath, "%s/%s%s", DEVPATH, dname, HDSUF);
33			#else
34			sprintf(dpath, "dev/%s%s", dname, HDSUF);
35			#endif
36	gregl	3.5	com[0] = dpath; com[1] = froot; com[2] = NULL;
37	gregl	3.2	pipesiz = open_process(dpd, com);
38			if (pipesiz <= 0)
39			error(USER, "cannot start display process");
40	gregl	3.5	if ((dpout = fdopen(dup(dpd[1]), "w")) == NULL)
41			error(SYSTEM, "cannot associate FILE with display pipe");
42	gregl	3.2	inp_flags = 0;
43			/* write out hologram grids */
44			for (i = 0; hdlist[i] != NULL; i++)
45			disp_result(DS_ADDHOLO, sizeof(HDGRID), (char *)hdlist[i]);
46	gregl	3.5	disp_flush();
47	gregl	3.1	}
48
49
50	gregl	3.2	disp_packet(p) /* display a packet */
51	gregl	3.4	register PACKHEAD *p;
52	gregl	3.2	{
53	gregl	3.4	disp_result(DS_BUNDLE, packsiz(p->nr), (char *)p);
54	gregl	3.2	}
55
56
57	gregl	3.1	disp_check(block) /* check display process */
58			int block;
59			{
60	gregl	3.2	MSGHEAD msg;
61			int n;
62			char *buf = NULL;
63
64			if (pipesiz <= 0)
65			return(-1);
66	gregl	3.5	/* flush display output */
67			disp_flush();
68	gregl	3.3	/* check read blocking */
69	gregl	3.2	if (block != (inp_flags == 0)) {
70			inp_flags = block ? 0 : FNONBLK;
71			if (fcntl(dpd[0], F_SETFL, inp_flags) < 0)
72			goto fcntlerr;
73			}
74			/* read message header */
75			n = read(dpd[0], (char *)&msg, sizeof(MSGHEAD));
76			if (n != sizeof(MSGHEAD)) {
77			if (n >= 0)
78			error(USER, "display process died");
79			if (errno != EAGAIN & errno != EINTR)
80			goto readerr;
81	gregl	3.3	return(2); /* acceptable failure */
82	gregl	3.2	}
83			if (msg.nbytes) { /* get the message body */
84			buf = (char *)malloc(msg.nbytes);
85			if (buf == NULL)
86			error(SYSTEM, "out of memory in disp_check");
87			if (fcntl(dpd[0], F_SETFL, inp_flags=0) < 0)
88			goto fcntlerr;
89			if (readbuf(dpd[0], buf, msg.nbytes) != msg.nbytes)
90			goto readerr;
91			}
92			switch (msg.type) { /* take appropriate action */
93			case DR_BUNDLE:
94			if (msg.nbytes != sizeof(PACKHEAD))
95			error(INTERNAL, "bad DR_BUNDLE from display process");
96			bundle_set(BS_ADD, (PACKHEAD *)buf, 1);
97			break;
98			case DR_NEWSET:
99			if (msg.nbytes % sizeof(PACKHEAD))
100			error(INTERNAL, "bad DR_NEWSET from display process");
101			disp_result(DS_STARTIMM, 0, NULL);
102			bundle_set(BS_NEW, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
103			disp_result(DS_ENDIMM, 0, NULL);
104	gregl	3.5	disp_flush();
105	gregl	3.2	break;
106			case DR_ADDSET:
107			if (msg.nbytes % sizeof(PACKHEAD))
108			error(INTERNAL, "bad DR_ADDSET from display process");
109			disp_result(DS_STARTIMM, 0, NULL);
110			bundle_set(BS_ADD, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
111			disp_result(DS_ENDIMM, 0, NULL);
112	gregl	3.5	disp_flush();
113	gregl	3.2	break;
114			case DR_DELSET:
115			if (msg.nbytes % sizeof(PACKHEAD))
116			error(INTERNAL, "bad DR_DELSET from display process");
117			bundle_set(BS_DEL, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
118			break;
119			case DR_ATTEN:
120			if (msg.nbytes)
121			error(INTERNAL, "bad DR_ATTEN from display process");
122			/* send acknowledgement */
123			disp_result(DS_ACKNOW, 0, NULL);
124	gregl	3.3	return(disp_check(1)); /* block on following request */
125	gregl	3.2	case DR_SHUTDOWN:
126			if (msg.nbytes)
127			error(INTERNAL, "bad DR_SHUTDOWN from display process");
128			return(0); /* zero return signals shutdown */
129			default:
130			error(INTERNAL, "unrecognized request from display process");
131			}
132	gregl	3.3	if (msg.nbytes) /* clean up */
133	gregl	3.2	free(buf);
134			return(1); /* normal return value */
135			fcntlerr:
136			error(SYSTEM, "cannot change display blocking mode");
137			readerr:
138			error(SYSTEM, "error reading from display process");
139	gregl	3.1	}
140
141
142	gregl	3.2	int
143			disp_close() /* close our display process */
144	gregl	3.1	{
145	gregl	3.2	int rval;
146
147			if (pipesiz <= 0)
148			return(-1);
149			disp_result(DS_SHUTDOWN, 0, NULL);
150	gregl	3.5	fclose(dpout);
151			dpout = NULL;
152	gregl	3.2	pipesiz = 0;
153			return(close_process(dpd));
154			}
155
156
157	gregl	3.5	disp_result(type, nbytes, p) /* queue result message to display process */
158	gregl	3.2	int type, nbytes;
159			char *p;
160			{
161			MSGHEAD msg;
162
163			msg.type = type;
164			msg.nbytes = nbytes;
165	gregl	3.5	fwrite((char *)&msg, sizeof(MSGHEAD), 1, dpout);
166			if (nbytes > 0)
167			fwrite(p, 1, nbytes, dpout);
168			}
169
170
171			disp_flush() /* flush output to display */
172			{
173			if (fflush(dpout) < 0)
174			error(SYSTEM, "error writing to the display process");
175	gregl	3.1	}