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root/radiance/ray/src/hd/rholo4.c
Revision: 3.5
Committed: Mon Nov 10 18:07:15 1997 UTC (26 years, 4 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

File Contents

# Content
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 #include <sys/uio.h>
14
15 #ifndef HDSUF
16 #define HDSUF ".hdisp"
17 #endif
18
19 static int inp_flags;
20 static int dpd[3];
21 static int pipesiz;
22 static FILE *dpout;
23
24
25 disp_open(dname) /* open the named display driver */
26 char *dname;
27 {
28 char dpath[128], *com[3];
29 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 com[0] = dpath; com[1] = froot; com[2] = NULL;
37 pipesiz = open_process(dpd, com);
38 if (pipesiz <= 0)
39 error(USER, "cannot start display process");
40 if ((dpout = fdopen(dup(dpd[1]), "w")) == NULL)
41 error(SYSTEM, "cannot associate FILE with display pipe");
42 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 disp_flush();
47 }
48
49
50 disp_packet(p) /* display a packet */
51 register PACKHEAD *p;
52 {
53 disp_result(DS_BUNDLE, packsiz(p->nr), (char *)p);
54 }
55
56
57 disp_check(block) /* check display process */
58 int block;
59 {
60 MSGHEAD msg;
61 int n;
62 char *buf = NULL;
63
64 if (pipesiz <= 0)
65 return(-1);
66 /* flush display output */
67 disp_flush();
68 /* check read blocking */
69 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 return(2); /* acceptable failure */
82 }
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 disp_flush();
105 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 disp_flush();
113 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 return(disp_check(1)); /* block on following request */
125 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 if (msg.nbytes) /* clean up */
133 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 }
140
141
142 int
143 disp_close() /* close our display process */
144 {
145 int rval;
146
147 if (pipesiz <= 0)
148 return(-1);
149 disp_result(DS_SHUTDOWN, 0, NULL);
150 fclose(dpout);
151 dpout = NULL;
152 pipesiz = 0;
153 return(close_process(dpd));
154 }
155
156
157 disp_result(type, nbytes, p) /* queue result message to display process */
158 int type, nbytes;
159 char *p;
160 {
161 MSGHEAD msg;
162
163 msg.type = type;
164 msg.nbytes = nbytes;
165 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 }