/* The proccom routine processes the data from the program controlling the */
/* display server.  Each message can contain more than one command.  If a */
/* values of 0 is passed for len than this is assumed to be the last time */
/* this routine is to be called in this particular incrementat transfer. */
/* Return Values: */
/* SUCCEED	If everything went fine */
/* BADCOM	If an invalid command was found */
/* INCCOM	If an incomplete command was sent.  This error code is only  */
/*		returned if this is the last transfer in an incremental */
/*		transfer. */
/* FAIL		If an X Window command fails */
/* MALLOC_ERR	If a malloc fails */

/* Sam Southard, Jr. */
/* Created: 6-Nov-1990 */
/* 15-Nov-1990	SNS/CIT	Modified to support commands being split across two */
/*			messages.  New format for TOK_DRAW_LINE and */
/*			TOK_DRAW_POLY (see commands.h) used.  All arguments */
/*			except for the pixel values for the bitmap write */
/*			command are now shorts. */
/* 16-Nov-1990	SNS/CIT	Code for TOK_SET_LG_SIZE, TOK_DRAW_DOT, */
/*			TOK_FILL_POLY, and TOK_FILL_RECT added. */
/* 19-Nov-1990	SNS/CIT	Code for TOK_LG_MAX_DIM, TOK_LG_SCALE, TOK_LG_CURS, */
/*			and TOK_LG_DEF_SIZE added. */
/*  8-Dec-1990	SNS/CIT	Now only does an XCopyArea once per call to proccom. */
/* 10-Dec-1990	SNS/CIT	Now uses wininfo structure.  VMS  changes merged in. */
/*			Now allows for 5 pixel border around graphics. */
/* 11-Dec-1990	SNS/CIT	TOK_RESET no longer clears the screen. */
/* 12-Dec-1990	SNS/CIT	Now handles bitmap graphics commands. */
/* 17-Dec-1990	SNS/CIT	Now uses the writeluts routine to handle the new */
/*			format for the TOK_SET_BM_LUT command. */
/*  2-Apr-1991	SNS/CIT	Image capbilities #ifdef'ed out for inclusion in the */
/*			Lick xvideo program. */
/*  3-Apr-1991	SNS/CIT	Image capabilities modified for use in Lick program. */
/*  8-Apr-1991	SNS/CIT	Modified to simply print an error message (instead of */
/*			exiting) when a bad command is encountered. */
/* 18-Apr-1991	SNS/CIT	Image LUT capabilities modified for Lick Xvideo. */
/* 20-Apr-1991	SNS/CIT	Cursor capabilities modified for Lick Xvideo. */
/* 22-Apr-1991	SNS/CIT	Now handles the TOK_SET_BM_CSCALE and */
/*			TOK_BM_SET_DSCALE commands. */
/*  6-May-1991	SNS/CIT	Added figim variable to help with color bar. */
/* 10-May-1991	SNS/CIT	Modified to be shared between Xvideo and pgdisp */
/* 17-Jun-1991	SNS/CIT	Now handles the TOK_BM_FLUSH command. */
/*			TOK_SET_BM_DSCALE modified to get a float param. */
/* 31-Jul-1991	SNS/CIT	Modified to be shared with fastdisp. */
/*  1-Aug-1991	SNS/CIT	Modified to handle the TOK_BM_LINE command. */
/*  7-Aug-1991	SNS/CIT	Now raises line graphics window when appropriate */
/* 14-Aug-1991	SNS/CIT	No longer contains hooks for xvideo */
/* 23-Aug-1991	SNS/CIT	Now updates the location window */
/*  5-Sep-1991	SNS/CIT	Modified to lint as cleanly as possible */
/*  8-Oct-1991	SNS/CIT	Globals moved into globals.h */
/* 14-Oct-1991	SNS/CIT	Allcells no longer in bm structure */
/* 17-Oct-1991	SNS/CIT	Modified to deal with 8 and 16 bit images */
/* 11-Feb-1992	SNS/CIT	Fixed bug causing line graphics data to be lost when */
/*			the user resized while a PGPLOT program was being run */
/* 14-Feb-1992	SNS/CIT	Now clears the line graphics window to lg.pix[0] not */
/*			BlackPixel */
/* 25-Feb-1992	SNS/CIT	Now handles line graphics windows with > 16 colors */
/* 26-Feb-1992	SNS/CIT	Now handles recieving bitmap graphics commands in */
/*			pgdisp and ignores commands in a buffer after an */
/*			unknown command has occurred. */
/*  5-Mar-1992	SNS/CIT	Line graphics now works on read-only & grey-scale */
/*			visuals. */
/*  9-Apr-1992	SNS/CIT	No longer has minimum and maximum window sizes in the */
/*			wininfo structure. */
/* 10-Apr-1992	SNS/CIT	Now knows how to handle lg.winxoff & lg.winyoff */
/* 14-Apr-1992	SNS/CIT	Now compiles under VMS */
/* 25-Jun-1992	SNS/CIT	SET_BM_LUT now has number of bits per pixel */
/*  9-Jul-1992	SNS/CIT	SET_LG_SIZE now takes the new size as claimed (it had */
/*			been taking the maximum coordinate, which is one */
/*			less) */
/* 22-Sep-1992	SNS/CIT	BM_ZOOMPAN implemented. */
/* 23-Sep-1992	SNS/CIT	SET_BM_DSCALE changed to use ASCII strings. */
/* 27-Sep-1992	SNS/CIT	Now allows for the server running on a machine with */
/*			a different byte order.  SET_LG_CSCALE changed to use */
/*			ASCII strings.  SET_BM_SH_SIZE and BM_SH_UPDATE */
/*			implemented. */
/* 28-Sep-1992	SNS/CIT	rcsid string added. */
/* 14-Oct-1992	SNS/CIT	Merged in changes from ARC/HI. */
/* 16-Oct-1992	SNS/CIT	Now resets goodhist for shared memory updates. */
/*  4-Nov-1992	SNS/CIT	AUTODISP command now takes ASCII-encoded strings. */
/*			LG_PIXLINE now resets the drawing color properly. */
/*			Extra arguments to XFillRectangle in SET_LG_SIZE */
/*			removed. */
/* 22-Aug-1994  TJP/CIT Fix bug in positioning thick dots. */

#ifndef lint
static char rcsid[]="@(#)$Id: proccom.c,v 1.17 1993/10/08 00:02:48 figaro Exp figaro $";
#endif

/* The system include files */
#include <stdio.h>
#include <sys/types.h>
#include <netinet/in.h>

#ifndef VMS
#include <values.h>
#endif

#ifdef sun
#include <memory.h>
#endif

/* The X Window include files */
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <X11/Intrinsic.h>
#include <X11/StringDefs.h>

/* The program include files */
#include "commands.h"
#include "figdisp.h"
#include "globals.h"
#include "messages.h"

/* A trivial macro */
#define min(x,y) (((x) > (y)) ? (y) : (x))

int proccom(buf,len,retbuf,retbuflen)
unsigned short *buf;	/* the buffer of commands and arguments */
int len;	/* the length of the buffer */
unsigned short *retbuf;	/* a buffer for return values */
int *retbuflen;	/* the length of retbuf */
{
	static short bufcont[7];	/* the buffer contents while we're */
					/* working on things */
	static int buflen;		/* the return buffer length */
	static int lgcolor;		/* the current color */
	static unsigned int lglinewid;	/* line graphics line width */

	int i,j,k,l;	/* silly loop variables */
	int thislut;	/* the current lut entry */
	XColor color;	/* a structure for changing LUTs */
	XPoint *points;	/* for drawing a poly line */
	int minx,maxx,miny,maxy;	/* minimum and maximum x and y for */
					/* updating an effected area */
	static int savedshorts=0;	/* The number of saved shorts */
	static short *olddata;		/* the saved data */
	int usedolddata=0;	/* if we use data from a previous call */
	unsigned short *bothbuf; /* buffer for sum of the two data parts */
		/* dimensions for updating screen */
	int cminx=lg.width,cmaxx=0,cminy=lg.height,cmaxy=0;
	Pixmap temppixmap;	/* a pixmap used to transfer from old size to */
				/* new size */
	int npix;		/* the number of pixels to write */
	short *sptr;		/* A pointer to a short */
	char *tmpptr;		/* A temporary pointer to a string. */
	double dtmp1, dtmp2;
#ifdef PGDISP
	int badbmcom=0;		/* if a bitmap command is recieved in PGDISP */
	int bppix,startx,starty,nline;	/* vars to decode commands */
#else
	unsigned short *im16;	/* used to access the image */
	unsigned char *im8;	/* used to access the 8-bit image */
	/* note that this should be short even in FASTDISP */
	short *tempim;		/* a pointer to  new image structure */
#endif
	void initlgluts();	/* initialize the LUTs */
	void pgscurs();		/* set the line graphics cursor position */
	void returnbuf();	/* return the answer to the client */
	void bmscurs();		/* set the bitmap graphics cursor position */
	void redrawim();	/* redraw the bitmap graphics window */
	void drawline();	/* draw a line in the bitmap window */
	Pixmap XCreatePixmap();

	char *malloc();

	if (!len & savedshorts)
	{ /* an incomplete command was sent! */
		savedshorts=0;
		free((char *)olddata);
		return(INCCOM);
	}
	if (savedshorts)
	{ /* There's some data left over from the old command */
		usedolddata=1;
#ifdef lint
		bothbuf=NULL;
		if (!(malloc(
#else
		if (!(bothbuf=(unsigned short *)malloc(
#endif
			(unsigned)(savedshorts+len)*sizeof(unsigned short))))
		{
			(void)fprintf(stderr,MSG_MALLOC);
			return(MALLOC_ERR);
		}
		/* first old data */
		(void)memcpy((char *)bothbuf,(char *)olddata,
			savedshorts*sizeof(short));
		/* then new data */
		(void)memcpy((char *)(bothbuf+savedshorts),(char *)buf,
			len*sizeof(short));
		len += savedshorts;
		buf=bothbuf;
		free((char *)olddata);
		savedshorts=0;
	}

	while (len-- > 0)
	{ /* until there are no more commands to process */
		switch(ntohs(*buf++))
		{
		case RESET:	/* reset the display server */
			initlgluts();
			lgcolor=1;
			lglinewid=0;
			XSetLineAttributes(display, linegc, lglinewid,
				LineSolid, CapRound, JoinRound);
			break;
		case SHOW_LG_WIN:	/* conceal/reveal line graphics */
			if (!len)
			{ /* save this data for the next time around */
				savedshorts=1;
				--buf;
				break;
			}
			if (ntohs(*buf++))
			{
				XMapWindow(display,lg.win);
				lg.mapped=1;
				XRaiseWindow(display,lg.win);
			} else {
				XUnmapWindow(display,lg.win);
				lg.mapped=0;
			}
			--len;
			break;
		case SET_LG_LUT:	/* set line graphics LUTs */
			if (len < 2)
			{ /* save the data */
				savedshorts=len+1;
				--buf;
				break;
			}
			thislut= ntohs(*buf++);
			i= ntohs(*buf++);
			len -= 2;
			if (len < 3*i)
			{
				savedshorts=len+3;
				buf -= 3;
				break;
			}
			color.flags = DoRed | DoGreen | DoBlue;
			while (thislut < lg.colors && i > 0)
			{
				color.pixel=lg.pix[thislut];
				color.red= ntohs(*buf++);
				color.green= ntohs(*buf++);
				color.blue= ntohs(*buf++);
				if (lg.bw)
				{
					color.red=0.30*color.red+
						0.59*color.green+
						0.11*color.blue;
					color.blue=color.green=color.red;
				}
				if (!lg.ro) XStoreColor(display, linecmap,
					&color);
				else {
					XAllocColor(display, linecmap, &color);
					lg.pix[thislut]=color.pixel;
					/* Did we change the foreground? */
					if (thislut == lgcolor)
						XSetForeground(display, linegc,
							lg.pix[lgcolor]);
					/* did we change the background? */
					if (thislut == 0)
						XSetBackground(display, linegc,
							0);
				}
				len -= 3;
				++thislut;
				--i;
			}
			/* eat up any extra LUT entries */
			buf += i*3;
			len -= i*3;
			break;
		case LG_CURS:	/* set and get cursor location */
			if (len < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			/* find out where the cursor is now */
			bufcont[0]= htons(LG_CURS);
			bufcont[1]= *buf++;
			bufcont[2]= *buf++;
			buflen=4;
			/* position the cursor */
			pgscurs(ntohs(bufcont[1]),ntohs(bufcont[2]));
			/* is an event already there? */
			if (pggcurs(&bufcont[0]))
			{ /* There's already an event there */
				returnbuf(&bufcont[0],4,srcwin);
				buflen=0;
			}
			len -= 2;
			break;
		case SET_LG_COL:	/* set the line graphics color index */
			if (!len)
			{
				savedshorts=1;
				--buf;
				break;
			}
			lgcolor= ntohs(*buf++);
			if (lgcolor >= lg.colors) lgcolor=1;
			XSetForeground(display, linegc, lg.pix[lgcolor]);
			--len;
			break;
		case DRAW_LINE:	/* draw a line */
			if (len < 4)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			maxx= ntohs(*buf++);
			maxy= ntohs(*buf++);
			XDrawLine(display, lg.pixmap, linegc, minx, miny, maxx,
				maxy);
			if (minx > maxx)
			{ /* swap for the XCopyArea */
				i=minx;
				minx=maxx;
				maxx=i;
			}
			if (miny > maxy)
			{ /* swap for the XCopyArea */
				i=miny;
				miny=maxy;
				maxy=i;
			}
			if (--minx < cminx) cminx=minx;
			if (++maxx > cmaxx) cmaxx=maxx;
			if (--miny < cminy) cminy=miny;
			if (++maxy > cmaxy) cmaxy=maxy;
			len -= 4;
			break;
		case DRAW_POLY:	/* draw a poly line */
			if (!len)
			{
				savedshorts=1;
				--buf;
				break;
			}
			i= ntohs(*buf++);
			/* se if there's enough data */
			if (--len < i*2)
			{
				savedshorts=len+2;
				buf -= 2;
			}
#ifdef lint
			points=NULL;
			if (!malloc((unsigned)i*sizeof(XPoint)))
#else
			if (!(points=(XPoint *)malloc(
				(unsigned)i*sizeof(XPoint))))
#endif
			{
				(void)fprintf(stderr,MSG_MALLOC);
				return(MALLOC_ERR);
			}
			j=0;
			minx=lg.width;
			maxx=0;
			miny=lg.height;
			maxy=0;
			while (i-- > 0)
			{
				if ((int)ntohs(*buf) < minx) minx= ntohs(*buf);
				if ((int)ntohs(*buf) > maxx) maxx= ntohs(*buf);
				points[j].x= ntohs(*buf++);
				if ((int)ntohs(*buf) < miny) miny= ntohs(*buf);
				if ((int)ntohs(*buf) > maxy) maxy= ntohs(*buf);
				points[j++].y= ntohs(*buf++);
				len -= 2;
			}
			XDrawLines(display, lg.pixmap, linegc, points, j,
				CoordModeOrigin);
			free((char *)points);
			if (--minx < cminx) cminx=minx;
			if (++maxx > cmaxx) cmaxx=maxx;
			if (--miny < cminy) cminy=miny;
			if (++maxy > cmaxy) cmaxy=maxy;
			break;
		case CLR_LG_WIN:	/* clear the line graphics window */
			XClearWindow(display,lg.win);
			XSetForeground(display, linegcclear, lg.pix[0]);
			XFillRectangle(display, lg.pixmap, linegcclear, 0, 0,
				lg.width, lg.height);
			cminx=0;
			cminy=0;
			cmaxx=lg.width;
			cmaxy=lg.height;
			break;
		case LG_MAX_DIM:	/* return maximum lg dimensions */
			bufcont[0]= htons(LG_MAX_DIM);
			bufcont[1]= htons(0);
			bufcont[2]= htons(LG_MAX_WIDTH-1);
			/* just so we're not too silly */
			if (LG_MAX_WIDTH < lg.width)
				bufcont[2]= htons(lg.width-1);
			bufcont[3]= htons(0);
			bufcont[4]= htons(LG_MAX_HEIGHT-1);
			if (LG_MAX_HEIGHT < lg.height)
				bufcont[4]= htons(lg.height-1);
			bufcont[5]= htons(0);
			bufcont[6]= htons(lg.colors-1);
			buflen=7;
			break;
		case LG_SCALE:
			bufcont[0]= htons(LG_SCALE);
			bufcont[1]= htons(DisplayWidthMM(display,screen));
			bufcont[2]= htons(DisplayHeightMM(display,screen));
			bufcont[3]= htons(DisplayWidth(display,screen));
			bufcont[4]= htons(DisplayHeight(display,screen));
			buflen=5;
			break;
		case LG_DEF_SIZE:
			bufcont[0]= htons(LG_DEF_SIZE);
			bufcont[1]= htons(0);
			bufcont[2]= htons(lg.width-1);
			bufcont[3]= htons(0);
			bufcont[4]= htons(lg.height-1);
			buflen=5;
			break;
		case SET_LG_SIZE:	/* set size of line graphics window */
			if (len < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			lg.imwidth= ntohs(*buf++);
			lg.imheight= ntohs(*buf++);
			len -= 2;
			/* now we get a pixmap for it.  Resizing the window */
			/* may override this, but if it does we won't lose */
			/* data we obtained in the mean time */
			temppixmap=XCreatePixmap(display,
				RootWindow(display,screen), lg.imwidth,
				lg.imheight, linedepth);
			XSetForeground(display, linegcclear, lg.pix[0]);
			XFillRectangle(display, temppixmap, linegcclear, 0, 0,
				lg.imwidth, lg.imheight);
			XCopyArea(display, lg.pixmap, temppixmap, linegc, 0, 0,
				lg.imwidth, lg.imheight, 0, 0);
			XFreePixmap(display, lg.pixmap);
			lg.pixmap=temppixmap;
			/* clear the window */
			XFillRectangle(display, lg.win, linegcclear, 0, 0,
				lg.width, lg.height);
			lg.winxoff=(lg.width-lg.imwidth)/2;
			lg.winyoff=(lg.height-lg.imheight)/2;
			XCopyArea(display, lg.pixmap, lg.win, linegc, 0, 0,
				lg.imwidth, lg.imheight, lg.winxoff,
				lg.winyoff);
			XResizeWindow(display,lg.win,lg.imwidth,lg.imheight);
			break;
		case DRAW_DOT:
			if (len < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			maxy=lglinewid>>1;
			if (lglinewid < 2)
			{
				XDrawPoint(display, lg.pixmap, linegc, minx,
					miny);
				if (--minx < cminx) cminx=minx;
				if (--miny < cminy) cminy=miny;
				minx += 2;
				miny += 2;
				if (minx > cmaxx) cmaxx=minx;
				if (miny > cmaxy) cmaxy=miny;
			} else {
                                int radius = lglinewid/2;
                                unsigned int diameter = radius*2;
                                minx -= radius;
                                miny -= radius;
                                XFillArc(display, lg.pixmap, linegc, minx,
                                        miny, diameter, diameter, 0, 23040);
                                if (--minx < cminx) cminx=minx;
                                if (--miny < cminy) cminy=miny;
                                minx += diameter+2;
                                miny += diameter+2;
                                if (minx > cmaxx) cmaxx=minx;
                                if (miny > cmaxy) cmaxy=miny;
  			}
			len -= 2;
			break;
		case FILL_POLY:
			if (!len)
			{
				savedshorts=1;
				--buf;
				break;
			}
			i= ntohs(*buf++);
			/* se if there's enough data */
			if (--len < i*2)
			{
				savedshorts=len+2;
				buf -= 2;
			}
#ifdef lint
			if (!malloc((unsigned)i*sizeof(XPoint)))
#else
			if (!(points=(XPoint *)malloc(
				(unsigned)i*sizeof(XPoint))))
#endif
			{
				(void)fprintf(stderr,MSG_MALLOC);
				return(MALLOC_ERR);
			}
			j=0;
			minx=lg.width;
			maxx=0;
			miny=lg.height;
			maxy=0;
			while (i-- > 0)
			{
				if ((int)ntohs(*buf) < minx) minx= ntohs(*buf);
				if ((int)ntohs(*buf) > maxx) maxx= ntohs(*buf);
				points[j].x= ntohs(*buf++);
				if ((int)ntohs(*buf) < miny) miny= ntohs(*buf);
				if ((int)ntohs(*buf) > maxy) maxy= ntohs(*buf);
				points[j++].y= ntohs(*buf++);
				len -= 2;
			}
			XFillPolygon(display, lg.pixmap, linegc, points, j,
				Complex, CoordModeOrigin);
			free((char *)points);
			if (--minx < cminx) cminx=minx;
			if (++maxx > cmaxx) cmaxx=maxx;
			if (--miny < cminy) cminy=miny;
			if (++maxy > cmaxy) cmaxy=maxy;
			break;
		case FILL_RECT:
			if (len < 4)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			maxx= ntohs(*buf++);
			maxy= ntohs(*buf++);
			len -= 4;
			if (minx > maxx)
			{
				i=minx;
				minx=maxx;
				maxx=i;
			}
			if (miny > maxy)
			{
				i=miny;
				miny=maxy;
				maxy=i;
			}
			XFillRectangle(display, lg.pixmap, linegc, minx, miny,
				(unsigned)(maxx-minx), (unsigned)(maxy-miny));
			if (--minx < cminx) cminx=minx;
			if (++maxx > cmaxx) cmaxx=maxx;
			if (--miny < cminy) cminy=miny;
			if (++maxy > cmaxy) cmaxy=maxy;
			break;
		case LG_LINE_WID:
			if (!len)
			{
				savedshorts=1;
				--buf;
				break;
			}
			lglinewid= ntohs(*buf++);
			XSetLineAttributes(display, linegc, lglinewid,
				LineSolid, CapRound, JoinRound);
			--len;
			break;
		case LG_PIXLINE:
			if (len < 4)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			npix= ntohs(*buf++);
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			len -= 3;
			if (len < npix)
			{
				savedshorts=len+4;
				buf -= 4;
				break;
			}
			for (i=0 ; i < npix; ++i)
			{
				XSetForeground(display, linegc,
					lg.pix[(int)ntohs(*buf++) % lg.colors]);
				XDrawPoint(display, lg.pixmap, linegc, minx++,
					miny);
			}
			len -= npix;
			if (--minx < cminx) cminx=minx;
			if (minx+npix+2 > cmaxx) cmaxx=minx+npix+2;
			XSetForeground(display, linegc, lg.pix[lgcolor]);
			if (--miny < cminy) cminy=miny;
			if (miny+2 > cmaxy) cmaxy=miny+2;
			break;
		case SET_LG_CSCALE:
			tmpptr= (char *)buf;
			/* make sure that there are enough nulls in the data */
			j=i=0;
			while (i < len*2 && j < 4)
			{
				if (tmpptr[i] == '\0')
					++j;
				++i;
			}
			if (j < 4)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			i= strlen(tmpptr) + 1;
			j= strlen(tmpptr+i) + 1;
			k= strlen(tmpptr+i+j) + 1;
			l= strlen(tmpptr+i+j+k) + 1;
			sscanf(tmpptr, "%e", &lg.curxoff);
			sscanf(tmpptr+i, "%e", &lg.curxsc);
			sscanf(tmpptr+i+j, "%e", &lg.curyoff);
			sscanf(tmpptr+i+j+k, "%e", &lg.curysc);
			if (lg.curxsc == 0.0) lg.curxsc=1.0;
			if (lg.curysc == 0.0) lg.curysc=1.0;
			buf += (i+j+k+l+1)/2;
			len -= (i+j+k+l+1)/2;
			break;
		case SHOW_BM_WIN:	/* conceal/reveal bitmap graphics */
#ifdef PGDISP
			badbmcom=1;
#endif
			++buf;
			--len;
			/* isn't backwards compatibility nice? */
			break;
		case SET_BM_LUT:	/* set bitmap graphics LUTs */
#ifdef PGDISP
			badbmcom=1;
			if (len < 4)
			{
				savedshorts=len+1;
				--buf;
			} else {
				thislut= ntohs(*buf++);
				i= ntohs(*buf++);	/* bits-per-pixel */
				i= ntohs(*buf++);	/* number affected */
				j= ntohs(*buf++) & 0x7;	/* the affected luts */
				len -= 3;
				if (j && len < i || !j && len < 3*i)
				{
					savedshorts=len+4;
					buf -= 4;
				} else if (j) {
					len -= i;
					buf += i;
				} else {
					len -= 3*i;
					buf += 3*i;
				}
			}
#else
			savedshorts=writeluts(&buf,&len);
#endif
			break;
		case BM_SET_CURS:	/* set the cursor location */
#ifdef PGDISP
			buf += 2;
			len -= 2;
			badbmcom=1;
#else
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			bmscurs(minx,miny);
			len -= 2;
#endif
			break;
		case BM_GET_CURS:	/* set and get cursor location */
#ifdef PGDISP
			badbmcom=1;
#else
			/* get cursor location (must be done in mainloop) */
			bufcont[0]= htons(BM_GET_CURS);
			buflen=4;
			if (bmgcurs(&bufcont[0]))
			{ /* There's already an event there */
				returnbuf(&bufcont[0],4,srcwin);
				buflen=0;
			}
#endif
			break;
		case CLR_BM_WIN:	/* clear the bitmap graphics window */
#ifdef PGDISP
			badbmcom=1;
#else
			if (bppix == 16)
			{
				for (i=0, im16= rimdat.b16 ;
				     i < bm.imwidth*bm.imheight ; ++i)
					*im16++ = 0;
			} else {
				for (i=0, im8= rimdat.b8 ;
				     i < bm.imwidth*bm.imheight ; ++i)
					*im8++ = 0;
			}
			redrawim(0, 0, bm.imwidth-1, bm.imheight-1);
			(void)updateloc();
#endif
			break;
		case BM_MAX_DIM:	/* return maximum bitmap dimensions */
#ifdef PGDISP
			badbmcom=1;
#else
			/* This has no real relevance since it's only */
			/* dependant on memory, but we need to return */
			/* something. */
			bufcont[0]= htons(BM_MAX_DIM);
			bufcont[1]= htons(0);
			bufcont[2]= htons(BM_MAX_WIDTH-1);
			/* don't be silly */
			if (BM_MAX_WIDTH < bm.width)
				bufcont[2]= htons(bm.width-1);
			bufcont[3]= htons(0);
			bufcont[4]= htons(BM_MAX_HEIGHT-1);
			if (BM_MAX_HEIGHT < bm.height)
				bufcont[4]= htons(bm.height-1);
			bufcont[5]= htons(0);
			bufcont[6]= htons(BM_COLORS-1);
			buflen=7;
#endif
			break;
		case BM_DEF_SIZE:
#ifdef PGDISP
			badbmcom=1;
#else
			bufcont[0]= htons(BM_DEF_SIZE);
			bufcont[1]= htons(0);
			bufcont[2]= htons(bm.imwidth-1);
			bufcont[3]= htons(0);
			bufcont[4]= htons(bm.imheight-1);
			buflen=5;
#endif
			break;
		case SET_BM_SIZE:	/* set size of image */
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			buf += 3;
			len -= 3;
#else
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			maxx= ntohs(*buf++);
			if (maxx != 16 && maxx != 8) 
			{
				(void)fprintf(stderr,
					"Invalid bits-per-pixel (%d)!\n",maxx);
				(void)fprintf(stderr, "Assuming 8\n");
				(void)fprintf(stderr,
				  "Don't be surprised if things don't work\n");
				maxx=8;
			}
			len -= 3;
			if (minx=resizeim(minx,miny,maxx)) return(minx);
#endif
			break;
		case BM_WRITE:
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 6)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			bppix= ntohs(*buf++);
			startx= ntohs(*buf++);
			starty= ntohs(*buf++);
			npix= ntohs(*buf++);
			nline= ntohs(*buf++);
			len -= 5;
			if (bppix == 16 && len < npix*nline ||
			    len < ((npix*nline+1)>>1))
			{
				savedshorts=len+6;
				buf -= 6;
				break;
			} else if (bppix == 16) {
				buf += npix*nline;
				len -= npix*nline;
			} else {
				buf += ((npix*nline+1)>>1);
				len -= ((npix*nline+1)>>1);
			}
#else
			/* get the image size - writeimage takes care of */
			/* interpreting the rest of the arguments and */
			/* changing buf and len accordingly */
			minx= ntohs(*buf++);
			--len;
			if (minx == 16) savedshorts=writeimage16(&buf,&len);
			else savedshorts=writeimage(&buf,&len);
#endif
			break;
		case SET_BM_CSCALE:
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 6)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			buf += 6;
			len -= 6;
#else
			bm.curxsc= (short)ntohs(*buf++);
			bm.curxsc /= (short)ntohs(*buf++);
			bm.curxoff= (short)ntohs(*buf++);
			bm.curysc= (short)ntohs(*buf++);
			bm.curysc /= (short)ntohs(*buf++);
			bm.curyoff= -bm.imheight - (short)ntohs(*buf++);
			if (bm.curxsc == 0.0) bm.curxsc=1.0;
			if (bm.curysc == 0.0) bm.curysc=1.0;
			len -= 6;
#endif
			break;
		case SET_BM_DSCALE:
#ifdef PGDISP
			badbmcom=1;
#endif
			tmpptr= (char *)buf;
			/* make sure that there are enough nulls in the data */
			j=i=0;
			while (i < len*2 && j < 2)
			{
				if (tmpptr[i] == '\0')
					++j;
				++i;
			}
			if (j < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			i=strlen(tmpptr) + 1;
			j=strlen(tmpptr+i) + 1;
#ifndef PGDISP
			sscanf(tmpptr,"%e", &bm.dsc);
			sscanf(tmpptr+i,"%e", &bm.doff);
#endif
			buf += (i+j+1)/2;
			len -= (i+j+1)/2;
			break;
		case BM_FLUSH:
#ifdef PGDISP
			badbmcom=1;
#endif
			XFlush(display);
			break;
		case BM_LINE:
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 5)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			buf += 5;
			len -= 5;
#else
			minx= ntohs(*buf++);
			miny= ntohs(*buf++);
			maxx= ntohs(*buf++);
			maxy= ntohs(*buf++);
			drawline(minx,miny,maxx,maxy, ntohs(*buf++));
			len -= 5;
#endif
			break;
		case BM_ZOOMPAN:
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 4)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			buf += 4;
			len -= 4;
#else
			minx = ntohs(*buf++);
			miny = ntohs(*buf++);
			/* update our idea of the center */
			if (minx > 0 && miny > 0)
			{
				i = bm.xoff;
				bm.xoff = minx;
				j = bm.yoff;
				bm.yoff = miny;

				if (bm.xzoom >= 0)
					bm.xoff -= (bm.width >> (bm.xzoom+1));
				else if (bm.xzoom < -1)
					bm.xoff -= (bm.width << (-bm.xzoom-1));
				else bm.xoff -= bm.width;

				if (bm.yzoom >= 0)
					bm.yoff -= (bm.height >> (bm.yzoom+1));
				else if (bm.yzoom < -1)
					bm.yoff -= (bm.height << (-bm.yzoom-1));
				else bm.yoff -= bm.height;
				checkoff();
			}
			maxx = ntohs(*buf++);
			maxy = ntohs(*buf++);
			if (maxx != bm.xzoom && maxx < 30 ||
			    maxy != bm.yzoom && maxy < 30)
				zoomim(maxx, maxy);
			else if (i != bm.xoff || j != bm.yoff) {
				XFillRectangle(display, bm.win, bitgcclear, 0,
					0, bm.width, bm.height);
				redrawim(display_to_imagecol(0),
					display_to_imagerow(0),
					display_to_imagecol(bm.width-1),
					display_to_imagerow(bm.height-1));
			}
			/* update the cursor */
			updatetitle(imagecol_to_display(minx),
					imagerow_to_display(miny), 0);
			len -= 4;
#endif
			break;
		case SET_BM_SH_SIZE:
#ifdef PGDISP
			badbmcom=1;
			if (len < 5)
			{
				savedshorts = len+1;
				--buf;
				break;
			}
			buf += 3;
			len -= 4;
			switch(ntohs(*buf++))
			{
			case 1: /* Sun shared memory - the only kind so far */
				if (len < 2)
				{
					savedshorts = len+5;
					buf -= 5;
					break;
				}
				break;
			}
			break;
#else
			savedshorts=resizeshm(&buf, &len);
#endif
			break;
		case BM_SH_UPDATE:
#ifdef PGDISP
			badbmcom=1;
#endif
			if (len < 4)
			{
				savedshorts = len+1;
				--buf;
				break;
			}
#ifdef PGDISP
			buf += 4;
			len -= 4;
#else
			minx = ntohs(*buf++);
			miny = ntohs(*buf++);
			maxx = ntohs(*buf++);
			maxy = ntohs(*buf++);

			/* all we need to do is update the display if shared */
			/* memory is actually being used. */
			if (shmtype != -1)
			{
				goodhist=0;
				redrawim(minx, miny, minx+maxx-1, miny+maxy-1);
			}
			len -= 4;
#endif
			break;
		case DO_BOX:
#ifdef PGDISP
			badbmcom=1;
#else
			do_box();
#endif
			break;
		case DO_AUTODISP:
#ifdef PGDISP
			badbmcom=1;
#endif
			tmpptr= (char *)buf;
			/* make sure that there are enough nulls in the data */
			j=i=0;
			while (i < len*2 && j < 2)
			{
				if (tmpptr[i] == '\0')
					++j;
				++i;
			}
			if (j < 2)
			{
				savedshorts=len+1;
				--buf;
				break;
			}
			i=strlen(tmpptr) + 1;
			j=strlen(tmpptr+i) + 1;
			buf += (i+j+1)/2;
			len -= (i+j+1)/2;
#ifndef PGDISP
			sscanf(tmpptr,"%lg", &dtmp1);
			sscanf(tmpptr+i,"%lg", &dtmp2);
			if (dtmp2 <= dtmp1 || dtmp1 < 0.0 || dtmp2 > 100.0)
			{
				fprintf(stderr,
					"Ignoring invalid autodisp range.\n");
			} else {
				if (autodisp_lower != dtmp1/100.0 ||
				    autodisp_upper != dtmp2/100.0) goodhist=0;
				autodisp_lower=dtmp1/100.0;
				autodisp_upper=dtmp2/100.0;
			}
			usehist=0;
			useramp=1;
			if (!goodhist)
				calchist();
			imagescale(usehist, useramp);
			newmapping();
#endif
			break;
		case DO_HISTEQ:
#ifdef PGDISP
			badbmcom = 1;
#else
                        /*
                         *  Scale the image.
                         */
			usehist = 1; useramp = 0;
			imagescale( usehist, useramp );
#endif
			break;
		case FIGDISP_IDLE:
			sendidle = 1;
			break;
		case FIGDISP_POINTS:
			if (len < 2)
			{
				savedshorts = len+1;
				--buf;
				break;
			}
			minx = ntohs (*buf++);
			maxx = ntohs (*buf++);
			len -= 2;
			if (len < 3*minx)
			{
				savedshorts = len + 3;
				buf -= 3;
				break;
			}
#ifdef PGDISP
			badbmcom = 1;
#else
			write_points (minx, maxx, buf);
#endif
			len -= 3*minx;
			buf += 3*minx;
			break;
		default: /* unknown command */
			(void)printf("Unknown command %d\n",ntohs(*(buf-1)));
			(void)printf("Ignoring rest of command buffer\n");
			(void)fflush(stdout);
			len=0;
			break;
		}
		/* do we need to save any values for the next call? */
		if (savedshorts)
		{
			len=0;
#ifdef lint
			if (!(malloc(
#else
			if (!(olddata=(short *)malloc(
#endif
				(unsigned)savedshorts*sizeof(short))))
			{
				(void)fprintf(stderr,MSG_MALLOC);
				return(MALLOC_ERR);
			}
			/* copy data */
			for (i=0 ; i < savedshorts ; ++i) *olddata++ = *buf++;
			olddata -= savedshorts;
		}
	}

#ifdef PGDISP
	/* if we got a bitmap graphics command in pgdisp, print a warning */
	if (badbmcom)
	{
		(void)puts("Warning: received bitmap command in line ");
		(void)puts("graphics only mode!\n");
		(void)puts(
			"Should you be running figdisp instead of pgdisp?\n");
	}
#endif

	/* if we used old data, free up the buffer */
	if (usedolddata) free((char *)bothbuf);
	if (!savedshorts && buflen)
	{ /* if there's no incomplete command and we need to send a message */
		for (i=0 ; i < buflen ; ++i) retbuf[i]=bufcont[i];
		*retbuflen=buflen;
		buflen=0;
	}

#ifndef PGDISP
	/* now update the location window */
	(void)updateloc();
#endif

	/* now update the screen if necessary */
	if (lg.mapped && cmaxx >= cminx && cmaxy >= cminy)
	{
		XCopyArea(display, lg.pixmap, lg.win, linegc, cminx, cminy,
			(unsigned)(cmaxx-cminx), (unsigned)(cmaxy-cminy),
			cminx+lg.winxoff, cminy+lg.winyoff);
	}
	return(SUCCEED);
}