src/rt/devcomm.c

/* Copyright (c) 1988 Regents of the University of California */

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

/*
 *  devcomm.c - communication routines for separate drivers.
 *
 *      10/5/88
 */

#include <stdio.h>

#include <signal.h>

#include "color.h"

#include "driver.h"

#ifndef DEVPATH
#define DEVPATH         getenv("PATH")  /* device search path */
#endif

#ifndef BSD
#define vfork           fork
#endif

#ifndef WFLUSH
#define WFLUSH          30              /* flush after this many rays */
#endif

extern char     *getpath(), *getenv();

int     onsigio();

int     comm_close(), comm_clear(), comm_paintr(), comm_errout(),
                comm_getcur(), comm_comout(), comm_comin();

struct driver   comm_driver, comm_default = {
        comm_close, comm_clear, comm_paintr, comm_getcur,
        comm_comout, comm_comin,
        MAXRES, MAXRES, 0
};

FILE    *devin, *devout;

int     devchild;


struct driver *
comm_init(argv)                 /* set up and execute driver */
char    *argv[];
{
        char    *devname;
        int     p1[2], p2[2];

        if ((devname = getpath(argv[0], DEVPATH)) == NULL) {
                stderr_v(argv[0]);
                stderr_v(": not found\n");
                return(NULL);
        }
        if (pipe(p1) == -1 || pipe(p2) == -1)
                goto syserr;
        if ((devchild = vfork()) == 0) {
                close(p1[1]);
                close(p2[0]);
                if (p1[0] != 0) {
                        dup2(p1[0], 0);
                        close(p1[0]);
                }
                if (p2[1] != 1) {
                        dup2(p2[1], 1);
                        close(p2[1]);
                }
                execv(devname, argv);
                stderr_v(devname);
                stderr_v(": cannot execute\n");
                _exit(127);
        }
        if (devchild == -1)
                goto syserr;
        close(p1[0]);
        close(p2[1]);
        if ((devout = fdopen(p1[1], "w")) == NULL)
                goto syserr;
        if ((devin = fdopen(p2[0], "r")) == NULL)
                goto syserr;
        bcopy(&comm_default, &comm_driver, sizeof(comm_driver));
        signal(SIGIO, onsigio);
        errvec = comm_errout;                   /* set error vector */
        cmdvec = comm_comout;
        if (wrnvec != NULL)
                wrnvec = comm_comout;
        return(&comm_driver);
syserr:
        perror(argv[0]);
        return(NULL);
}


static
comm_close()                    /* done with driver */
{
        int     pid;

        errvec = stderr_v;                      /* reset error vector */
        cmdvec = NULL;
        if (wrnvec != NULL)
                wrnvec = stderr_v;
        signal(SIGIO, SIG_DFL);
        fclose(devout);
        fclose(devin);
        while ((pid = wait(0)) != -1 && pid != devchild)
                ;
}


static
comm_clear(xres, yres)                          /* clear screen */
int     xres, yres;
{
        putc(COM_CLEAR, devout);
        fwrite(&xres, sizeof(xres), 1, devout);
        fwrite(&yres, sizeof(yres), 1, devout);
        fflush(devout);
}


static
comm_paintr(col, xmin, ymin, xmax, ymax)        /* paint a rectangle */
COLOR   col;
int     xmin, ymin, xmax, ymax;
{
        extern long     nrays;          /* number of rays traced */
        static long     lastflush = 0;  /* ray count at last flush */

        putc(COM_PAINTR, devout);
        fwrite(col, sizeof(COLOR), 1, devout);
        fwrite(&xmin, sizeof(xmin), 1, devout);
        fwrite(&ymin, sizeof(ymin), 1, devout);
        fwrite(&xmax, sizeof(xmax), 1, devout);
        fwrite(&ymax, sizeof(ymax), 1, devout);
        if (nrays - lastflush >= WFLUSH) {
                fflush(devout);
                lastflush = nrays;
        }
}


static int
comm_getcur(xp, yp)                     /* get and return cursor position */
int     *xp, *yp;
{
        int     c;

        putc(COM_GETCUR, devout);
        fflush(devout);
        if (getc(devin) != COM_GETCUR)
                reply_error("getcur");
        c = getc(devin);
        fread(xp, sizeof(*xp), 1, devin);
        fread(yp, sizeof(*yp), 1, devin);
        return(c);
}


static
comm_comout(str)                        /* print string to command line */
char    *str;
{
        putc(COM_COMOUT, devout);
        myputs(str, devout);
        fflush(devout);
}


static
comm_comin(buf)                         /* read string from command line */
char    *buf;
{
        putc(COM_COMIN, devout);
        fflush(devout);
        if (getc(devin) != COM_COMIN)
                reply_error("comin");
        mygets(buf, devin);
        comm_driver.inpready = 0;
}


static
comm_errout(str)                        /* display an error message */
char    *str;
{
        comm_comout(str);
        stderr_v(str);                  /* send to standard error also */
}


static
mygets(s, fp)                           /* get string from file (with nul) */
register char   *s;
register FILE   *fp;
{
        register int    c;

        while ((c = getc(fp)) != EOF)
                if ((*s++ = c) == '\0')
                        return;
        *s = '\0';
}


static
myputs(s, fp)                           /* put string to file (with nul) */
register char   *s;
register FILE   *fp;
{
        do
                putc(*s, fp);
        while (*s++);
}


static
reply_error(routine)                    /* what should we do here? */
char    *routine;
{
        stderr_v(routine);
        stderr_v(": driver reply error\n");
        quit(1);
}


static
onsigio()                               /* input ready */
{
        comm_driver.inpready++;
}
Revision:	1.1
Committed:	Thu Feb 2 10:41:19 1989 UTC (36 years, 9 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Log Message:	Initial revision
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1988 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8			* devcomm.c - communication routines for separate drivers.
9			*
10			* 10/5/88
11			*/
12
13			#include <stdio.h>
14
15			#include <signal.h>
16
17			#include "color.h"
18
19			#include "driver.h"
20
21			#ifndef DEVPATH
22			#define DEVPATH getenv("PATH") /* device search path */
23			#endif
24
25			#ifndef BSD
26			#define vfork fork
27			#endif
28
29			#ifndef WFLUSH
30			#define WFLUSH 30 /* flush after this many rays */
31			#endif
32
33			extern char getpath(), getenv();
34
35			int onsigio();
36
37			int comm_close(), comm_clear(), comm_paintr(), comm_errout(),
38			comm_getcur(), comm_comout(), comm_comin();
39
40			struct driver comm_driver, comm_default = {
41			comm_close, comm_clear, comm_paintr, comm_getcur,
42			comm_comout, comm_comin,
43			MAXRES, MAXRES, 0
44			};
45
46			FILE devin, devout;
47
48			int devchild;
49
50
51			struct driver *
52			comm_init(argv) /* set up and execute driver */
53			char *argv[];
54			{
55			char *devname;
56			int p1[2], p2[2];
57
58			if ((devname = getpath(argv[0], DEVPATH)) == NULL) {
59			stderr_v(argv[0]);
60			stderr_v(": not found\n");
61			return(NULL);
62			}
63			if (pipe(p1) == -1 \|\| pipe(p2) == -1)
64			goto syserr;
65			if ((devchild = vfork()) == 0) {
66			close(p1[1]);
67			close(p2[0]);
68			if (p1[0] != 0) {
69			dup2(p1[0], 0);
70			close(p1[0]);
71			}
72			if (p2[1] != 1) {
73			dup2(p2[1], 1);
74			close(p2[1]);
75			}
76			execv(devname, argv);
77			stderr_v(devname);
78			stderr_v(": cannot execute\n");
79			_exit(127);
80			}
81			if (devchild == -1)
82			goto syserr;
83			close(p1[0]);
84			close(p2[1]);
85			if ((devout = fdopen(p1[1], "w")) == NULL)
86			goto syserr;
87			if ((devin = fdopen(p2[0], "r")) == NULL)
88			goto syserr;
89			bcopy(&comm_default, &comm_driver, sizeof(comm_driver));
90			signal(SIGIO, onsigio);
91			errvec = comm_errout; /* set error vector */
92			cmdvec = comm_comout;
93			if (wrnvec != NULL)
94			wrnvec = comm_comout;
95			return(&comm_driver);
96			syserr:
97			perror(argv[0]);
98			return(NULL);
99			}
100
101
102			static
103			comm_close() /* done with driver */
104			{
105			int pid;
106
107			errvec = stderr_v; /* reset error vector */
108			cmdvec = NULL;
109			if (wrnvec != NULL)
110			wrnvec = stderr_v;
111			signal(SIGIO, SIG_DFL);
112			fclose(devout);
113			fclose(devin);
114			while ((pid = wait(0)) != -1 && pid != devchild)
115			;
116			}
117
118
119			static
120			comm_clear(xres, yres) /* clear screen */
121			int xres, yres;
122			{
123			putc(COM_CLEAR, devout);
124			fwrite(&xres, sizeof(xres), 1, devout);
125			fwrite(&yres, sizeof(yres), 1, devout);
126			fflush(devout);
127			}
128
129
130			static
131			comm_paintr(col, xmin, ymin, xmax, ymax) /* paint a rectangle */
132			COLOR col;
133			int xmin, ymin, xmax, ymax;
134			{
135			extern long nrays; /* number of rays traced */
136			static long lastflush = 0; /* ray count at last flush */
137
138			putc(COM_PAINTR, devout);
139			fwrite(col, sizeof(COLOR), 1, devout);
140			fwrite(&xmin, sizeof(xmin), 1, devout);
141			fwrite(&ymin, sizeof(ymin), 1, devout);
142			fwrite(&xmax, sizeof(xmax), 1, devout);
143			fwrite(&ymax, sizeof(ymax), 1, devout);
144			if (nrays - lastflush >= WFLUSH) {
145			fflush(devout);
146			lastflush = nrays;
147			}
148			}
149
150
151			static int
152			comm_getcur(xp, yp) /* get and return cursor position */
153			int xp, yp;
154			{
155			int c;
156
157			putc(COM_GETCUR, devout);
158			fflush(devout);
159			if (getc(devin) != COM_GETCUR)
160			reply_error("getcur");
161			c = getc(devin);
162			fread(xp, sizeof(*xp), 1, devin);
163			fread(yp, sizeof(*yp), 1, devin);
164			return(c);
165			}
166
167
168			static
169			comm_comout(str) /* print string to command line */
170			char *str;
171			{
172			putc(COM_COMOUT, devout);
173			myputs(str, devout);
174			fflush(devout);
175			}
176
177
178			static
179			comm_comin(buf) /* read string from command line */
180			char *buf;
181			{
182			putc(COM_COMIN, devout);
183			fflush(devout);
184			if (getc(devin) != COM_COMIN)
185			reply_error("comin");
186			mygets(buf, devin);
187			comm_driver.inpready = 0;
188			}
189
190
191			static
192			comm_errout(str) /* display an error message */
193			char *str;
194			{
195			comm_comout(str);
196			stderr_v(str); /* send to standard error also */
197			}
198
199
200			static
201			mygets(s, fp) /* get string from file (with nul) */
202			register char *s;
203			register FILE *fp;
204			{
205			register int c;
206
207			while ((c = getc(fp)) != EOF)
208			if ((*s++ = c) == '\0')
209			return;
210			*s = '\0';
211			}
212
213
214			static
215			myputs(s, fp) /* put string to file (with nul) */
216			register char *s;
217			register FILE *fp;
218			{
219			do
220			putc(*s, fp);
221			while (*s++);
222			}
223
224
225			static
226			reply_error(routine) /* what should we do here? */
227			char *routine;
228			{
229			stderr_v(routine);
230			stderr_v(": driver reply error\n");
231			quit(1);
232			}
233
234
235			static
236			onsigio() /* input ready */
237			{
238			comm_driver.inpready++;
239			}