/* $Id: XWindow.c,v 1.38 2004/01/09 04:16:06 reinelt Exp $
 *
 * X11 Driver for LCD4Linux 
 *
 * Copyright 2000 Herbert Rosmanith <herp@wildsau.idv.uni-linz.ac.at>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * LCD4Linux is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * $Log: XWindow.c,v $
 * Revision 1.38  2004/01/09 04:16:06  reinelt
 * added 'section' argument to cfg_get(), but NULLed it on all calls by now.
 *
 * Revision 1.37  2004/01/06 22:33:14  reinelt
 * Copyright statements cleaned up
 *
 * Revision 1.36  2003/10/22 04:32:25  reinelt
 * fixed icon bug found by Rob van Nieuwkerk
 *
 * Revision 1.35  2003/10/05 17:58:50  reinelt
 * libtool junk; copyright messages cleaned up
 *
 * Revision 1.34  2003/09/10 14:01:53  reinelt
 * icons nearly finished\!
 *
 * Revision 1.33  2003/09/09 06:54:43  reinelt
 * new function 'cfg_number()'
 *
 * Revision 1.32  2003/07/24 04:48:09  reinelt
 * 'soft clear' needed for virtual rows
 *
 * Revision 1.31  2003/04/12 16:23:10  reinelt
 * small glitch in XWindow.c (thanks to Moe Wibble)
 *
 * Revision 1.30  2003/02/22 07:53:10  reinelt
 * cfg_get(key,defval)
 *
 * Revision 1.29  2003/02/18 06:13:44  reinelt
 * X11 driver fixes and cleanup
 *
 * Revision 1.28  2003/02/17 06:06:12  reinelt
 * small bug in X11 driver: omit pixel gap between cahracters
 *
 * Revision 1.27  2002/08/19 04:41:20  reinelt
 * introduced bar.c, moved bar stuff from display.h to bar.h
 *
 * Revision 1.26  2001/08/05 17:13:29  reinelt
 *
 * cleaned up inlude of sys/time.h and time.h
 *
 * Revision 1.25  2001/03/16 16:40:17  ltoetsch
 * implemented time bar
 *
 * Revision 1.24  2001/03/01 11:08:16  reinelt
 *
 * reworked configure to allow selection of drivers
 *
 * Revision 1.23  2001/02/26 00:33:37  herp
 * fixed X11 signal handler
 *
 * Revision 1.22  2001/02/13 09:00:13  reinelt
 *
 * prepared framework for GPO's (general purpose outputs)
 *
 * Revision 1.21  2000/08/10 18:42:20  reinelt
 *
 * fixed some bugs with the new syslog code
 *
 * Revision 1.20  2000/08/10 09:44:09  reinelt
 *
 * new debugging scheme: error(), info(), debug()
 * uses syslog if in daemon mode
 *
 * Revision 1.19  2000/08/09 09:50:29  reinelt
 *
 * opened 0.98 development
 * removed driver-specific signal-handlers
 * added 'quit'-function to driver structure
 * added global signal-handler
 *
 * Revision 1.18  2000/05/02 23:07:48  herp
 * Crystalfontz initial coding
 *
 * Revision 1.17  2000/04/05 05:58:36  reinelt
 *
 * fixed bug in XWindow.c: union semun isn't defined with glibc-2.1
 *
 * Revision 1.16  2000/04/03 23:53:23  herp
 * fixed a bug that caused pixel-errors ("fliegendreck") under high load
 *
 * Revision 1.15  2000/04/03 04:01:31  reinelt
 *
 * if 'gap' is specified as -1, a gap of (pixelsize+pixelgap) is selected automatically
 *
 * Revision 1.14  2000/04/02 22:07:10  herp
 * fixded a bug that occasionally caused Xlib errors
 *
 * Revision 1.13  2000/04/01 22:40:42  herp
 * geometric correction (too many pixelgaps)
 * lcd4linux main should return int, not void
 *
 * Revision 1.12  2000/04/01 19:33:45  herp
 *
 * colors in format \#RRGGBB in config-file now understood
 *
 * Revision 1.11  2000/04/01 16:22:38  reinelt
 *
 * bug that caused a segfault in processor.c fixed (thanks to herp)
 *
 * Revision 1.10  2000/03/31 01:42:11  herp
 *
 * semaphore bug fixed
 *
 * Revision 1.9  2000/03/30 16:46:57  reinelt
 *
 * configure now handles '--with-x' and '--without-x' correct
 *
 * Revision 1.8  2000/03/28 08:48:33  reinelt
 *
 * README.X11 added
 *
 * Revision 1.7  2000/03/28 07:22:15  reinelt
 *
 * version 0.95 released
 * X11 driver up and running
 * minor bugs fixed
 *
 */

/* 
 *
 * exported fuctions:
 *
 * struct LCD XWindow[]
 *
 */


/*
 * Mon Feb 26 02:07:52 MET 2001 fixed sighandler
 * Tue Apr  4 02:37:38 MET 2000 fixed a bug that caused pixelerrors under h/load
 * Sun Apr  2 22:07:10 MET 2000 fixed a bug that occasionally caused Xlib error
 * Sun Apr  2 01:32:48 MET 2000 geometric correction (too many pixelgaps)
 * Sat Apr  1 22:18:04 MET 2000 colors in format \#RRGGBB in config-file
 * Fri Mar 31 01:42:11 MET 2000 semaphore bug fixed
 * Sun Mar 26 15:28:23 MET 2000 various rewrites
 * Sat Mar 25 23:58:19 MET 2000 use generic pixmap driver
 * Thu Mar 23 01:05:07 MET 2000 multithreading, synchronization
 * Tue Mar 21 22:22:03 MET 2000 initial coding
 *
 */

#include	<X11/Xlib.h>
#include	<X11/Xutil.h>
#include	<stdio.h>
#include	<stdlib.h>
#include	<string.h>
#include	<errno.h>
#include	<sys/types.h>
#include	<sys/wait.h>
#include	<sys/ipc.h>
#include	<sys/sem.h>
#include	<sys/shm.h>
#include	<unistd.h>
#include        <signal.h>

#include        "debug.h"
#include	"cfg.h"
#include	"display.h"
#include        "bar.h"
#include        "icon.h"
#include	"pixmap.h"


/* glibc 2.1 requires defining semun ourselves */
#ifdef _SEM_SEMUN_UNDEFINED
union semun {
  int val;
  struct semid_ds *buf;
  unsigned short int *array;
  struct seminfo *__buf;
};
#endif


static LCD Lcd;
static Display *dp;
static int sc;
static Window w,rw;
static Visual *vi;
static int dd;
static Colormap cm;
static GC gc,gcb,gch;
static XColor co[3];
static Pixmap pmback;

static unsigned char *LCDpixmap2;
static char *rgbfg,*rgbbg,*rgbhg;
static int pixel=-1;			/*pointsize in pixel*/
static int pgap=0;			/*gap between points */
static int rgap=0;			/*row gap between lines*/
static int cgap=0;			/*column gap between characters*/
static int border=0;			/*window border*/
static int rows=-1,cols=-1;		/*rows+cols without background*/
static int xres=-1,yres=-1;		/*xres+yres (same as self->...)*/
static int icons;                       /* number of user-defined icons */
static int dimx,dimy;			/*total window dimension in pixel*/
static int boxw,boxh;			/*box width, box height*/
static int async_update();		/*PROTO*/
static pid_t async_updater_pid=1;
static int semid=-1;
static int shmid=-1;
static int ppid;			/*parent pid*/


static void acquire_lock() 
{
  struct sembuf sembuf;
  sembuf.sem_num=0;
  sembuf.sem_op=-1;
  sembuf.sem_flg=0;
  semop(semid,&sembuf,1);		/* get mutex */
}


static void release_lock() 
{
  struct sembuf sembuf;
  sembuf.sem_num=0;
  sembuf.sem_op=1;
  sembuf.sem_flg=0;
  semop(semid,&sembuf,1);		/* free mutex */
}


static void semcleanup() 
{
  union semun arg;
  if (semid>-1) semctl(semid,0,IPC_RMID,arg);
}


static void shmcleanup() 
{
  if (shmid>-1) shmctl(shmid,IPC_RMID,NULL);
}


static void quit_updater() 
{
  int i;
  if (async_updater_pid>1) {
    i=async_updater_pid;
    async_updater_pid=1;
    kill(i,9);
    waitpid(i,&i,0);
  }
}


static void sig_updater(int sig) 
{
  kill(ppid,sig);
  exit(0);
}


static void init_signals() 
{
  unsigned int ignsig=(1<<SIGBUS)|(1<<SIGFPE)|(1<<SIGSEGV)|
    (1<<SIGTSTP)|(1<<SIGCHLD)|(1<<SIGCONT)|
    (1<<SIGTTIN)|(1<<SIGWINCH);
  int i;
  for(i=0;i<NSIG;i++)
    if (((1<<i)&ignsig)==0)
      signal(i,sig_updater);
  
}


static int init_shm(int nbytes,unsigned char **buf) 
{
  shmid=shmget(IPC_PRIVATE,nbytes,SHM_R|SHM_W);
  if (shmid==-1) {
    error ("X11: shmget() failed: %s", strerror(errno));
    return -1;
  }
  *buf=shmat(shmid,NULL,0);
  if (*buf==NULL) {
    error ("X11: shmat() failed: %s", strerror(errno));
    return -1;
  }
  return 0;
}


/* acording to SUN-Solaris man-pages: */
#define SEM_ALTER 0200

static int init_thread(int bufsiz) 
{
  union semun semun;
  
  semid=semget(IPC_PRIVATE,1,SEM_ALTER);
  if (semid==-1) {
    error ("X11: semget() failed: %s", strerror(errno));
    return -1;
  }
  semun.val=1;
  semctl(semid,0,SETVAL,semun);
  
  ppid=getpid();
  switch(async_updater_pid=fork()) {
  case -1:
    error ("X11: fork() failed: %s", strerror(errno));
    return -1;
  case 0:
    async_update();
    error ("X11: async_update failed");
    kill(ppid,SIGTERM);
    exit(-1);
  default:
    break;
  }
  signal(SIGCHLD,quit_updater);
  atexit(quit_updater);
  return 0;
}


static int init_x(int rows,int cols,int xres,int yres) 
{
  XSetWindowAttributes wa;
  XSizeHints size_hints;
  XColor co_dummy;
  XEvent ev;

  if ((dp=XOpenDisplay(NULL))==NULL) {
    error ("X11: can't open display");
    return -1;
  }
  sc=DefaultScreen(dp);
  gc=DefaultGC(dp,sc);
  vi=DefaultVisual(dp,sc);
  dd=DefaultDepth(dp,sc);
  rw=DefaultRootWindow(dp);
  cm=DefaultColormap(dp,sc);

  if (XAllocNamedColor(dp,cm,rgbfg,&co[0],&co_dummy)==False) {
    error ("X11: can't alloc foreground color '%s'",
	   rgbfg);
    return -1;
  }
  if (XAllocNamedColor(dp,cm,rgbbg,&co[1],&co_dummy)==False) {
    error ("X11: can't alloc background color '%s'",
	   rgbbg);
    return -1;
  }
  if (XAllocNamedColor(dp,cm,rgbhg,&co[2],&co_dummy)==False) {
    error ("X11: can't alloc halfground color '%s'",
	   rgbhg);
    return -1;
  }
  boxw=xres*pixel+(xres-1)*pgap+cgap;
  boxh=yres*pixel+(yres-1)*pgap+rgap;
  dimx=cols*xres*pixel+(cols*xres-1)*pgap+(cols-1)*cgap;
  dimy=rows*yres*pixel+(rows*yres-1)*pgap+(rows-1)*rgap;
  wa.event_mask=ExposureMask;
  w=XCreateWindow(dp,rw,0,0,dimx+2*border,dimy+2*border,0,0,
		  InputOutput,vi,CWEventMask,&wa);
  pmback=XCreatePixmap(dp,w,dimx,dimy,dd);
  size_hints.min_width=size_hints.max_width=dimx+2*border;
  size_hints.min_height=size_hints.max_height=dimy+2*border;
  size_hints.flags=PPosition|PSize|PMinSize|PMaxSize;
  XSetWMProperties(dp,w,NULL,NULL,NULL,0,&size_hints,NULL,NULL);
  XSetForeground(dp,gc,co[0].pixel);
  XSetBackground(dp,gc,co[1].pixel);
  gcb=XCreateGC(dp,w,0,NULL);
  XSetForeground(dp,gcb,co[1].pixel);
  XSetBackground(dp,gcb,co[0].pixel);
  gch=XCreateGC(dp,w,0,NULL);
  XSetForeground(dp,gch,co[2].pixel);
  XSetBackground(dp,gch,co[0].pixel);
  XFillRectangle(dp,pmback,gcb,0,0,dimx,dimy);
  XSetWindowBackground(dp,w,co[1].pixel);
  XClearWindow(dp,w);
  XStoreName(dp,w,"XLCD4Linux");
  XMapWindow(dp,w);
  XFlush(dp);
  for(;;) {
    XNextEvent(dp,&ev);
    if (ev.type==Expose && ev.xexpose.count==0)
      break;
  }
  return 0;
}


int xlcdinit(LCD *Self) 
{
  char *s;

  if (sscanf(s=cfg_get(NULL, "size", "20x4"),"%dx%d",&cols,&rows)!=2
      || rows<1 || cols<1) {
    error ("X11: bad size '%s'",s);
    return -1;
  }
  if (sscanf(s=cfg_get(NULL, "font", "5x8"),"%dx%d",&xres,&yres)!=2
      || xres<5 || yres>10) {
    error ("X11: bad font '%s'",s);
    return -1;
  }
  if (sscanf(s=cfg_get(NULL, "pixel", "4+1"),"%d+%d",&pixel,&pgap)!=2
      || pixel<1 || pgap<0) {
    error ("X11: bad pixel '%s'",s);
    return -1;
  }
  if (sscanf(s=cfg_get(NULL, "gap", "-1x-1"),"%dx%d",&cgap,&rgap)!=2
      || cgap<-1 || rgap<-1) {
    error ("X11: bad gap '%s'",s);
    return -1;
  }
  if (rgap<0) rgap=pixel+pgap;
  if (cgap<0) cgap=pixel+pgap;

  if (cfg_number(NULL, "border", 0, 0, 1000000, &border)<0) return -1;

  rgbfg=cfg_get(NULL, "foreground", "#000000");
  rgbbg=cfg_get(NULL, "background", "#80d000");
  rgbhg=cfg_get(NULL, "halfground", "#70c000");
  if (*rgbfg=='\\') rgbfg++;
  if (*rgbbg=='\\') rgbbg++;
  if (*rgbhg=='\\') rgbhg++;

  if (pix_init(rows,cols,xres,yres)==-1) return -1;

  if (cfg_number(NULL, "Icons", 0, 0, 8, &icons) < 0) return -1;
  if (icons>0) {
    info ("allocating %d icons", icons);
    icon_init(rows, cols, xres, yres, 8, icons, pix_icon);
  }
  
  if (init_x(rows,cols,xres,yres)==-1) return -1;
  init_signals();
  if (init_shm(rows*cols*xres*yres,&LCDpixmap2)==-1) return -1;
  memset(LCDpixmap2,0xff,rows*yres*cols*xres);
  if (init_thread(rows*cols*xres*yres)==-1) return -1;
  Self->rows=rows;
  Self->cols=cols;
  Self->xres=xres;
  Self->yres=yres;
  Self->icons=icons;
  Lcd=*Self;

  pix_clear();
  return 0;
}


int xlcdclear(int full) 
{
  icon_clear();
  pix_clear();
  return 0;
}


int xlcdput(int row,int col, char *text) 
{
  return pix_put(row,col,text);
}


int xlcdbar(int type, int row, int col, int max, int len1, int len2) 
{
  return pix_bar(type,row,col,max,len1,len2);
}


int xlcdicon (int num, int seq, int row, int col)
{
  return icon_draw (num, seq, row, col);
}


int xlcdflush() {
  int dirty;
  int row,col;
  
  acquire_lock();
  dirty=0;
  for(row=0;row<rows*yres;row++) {
    int y=border+(row/yres)*rgap+row*(pixel+pgap);
    for(col=0;col<cols*xres;col++) {
      int x=border+(col/xres)*cgap+col*(pixel+pgap);
      int p=row*cols*xres+col;
      if (LCDpixmap[p]^LCDpixmap2[p]) {
	XFillRectangle(dp,w,LCDpixmap[p]?gc:gch,x,y,pixel,pixel);
	LCDpixmap2[p]=LCDpixmap[p];
	dirty=1;
      }
    }
  }
  if (dirty) XSync(dp,False);
  release_lock();
  return 0;
}


int xlcdquit(void) 
{
  semcleanup();
  shmcleanup();
  quit_updater();
  return 0;
}


/*
 * this one should only be called from the updater-thread
 * no user serviceable parts inside
 */

static void update(int x,int y,int width,int height)
{
  /*
   * theory of operation:
   * instead of the old, fully-featured but complicated update
   * region calculation, we do an update of the whole display,
   * but check before every pixel if the pixel region is inside
   * the update region.
   */

  int x0, y0;
  int x1, y1;
  int row, col;
  int dirty;
  
  x0=x-pixel;
  y0=y-pixel;
  x1=x+pixel+width;
  y1=y+pixel+height;
  
  dirty=0;
  for(row=0;row<rows*yres;row++) {
    int y=border+(row/yres)*rgap+row*(pixel+pgap);
    if (y<y0 || y>y1) continue;
    for(col=0;col<cols*xres;col++) {
      int x=border+(col/xres)*cgap+col*(pixel+pgap);
      int p;
      if (x<x0 || x>x1) continue;
      p=row*cols*xres+col;
      XFillRectangle(dp,w,LCDpixmap2[p]?gc:gch,x,y,pixel,pixel);
      dirty=1;
    }
  }
  if (dirty) XSync(dp,False);
}


static int async_update() 
{
  XSetWindowAttributes wa;
  XEvent ev;

  if ((dp=XOpenDisplay(NULL))==NULL)
    return -1;
  wa.event_mask=ExposureMask;
  XChangeWindowAttributes(dp,w,CWEventMask,&wa);
  for(;;) {
    XWindowEvent(dp,w,ExposureMask,&ev);
    if (ev.type==Expose) {
      acquire_lock();
      update(ev.xexpose.x,ev.xexpose.y,
	     ev.xexpose.width,ev.xexpose.height);
      release_lock();
    }
  }
}


LCD XWindow[] = {
  { name: "X11",
    rows:  0,
    cols:  0,
    xres:  0,
    yres:  0,
    bars:  BAR_L | BAR_R | BAR_U | BAR_D | BAR_H2 | BAR_V2 | BAR_T,
    icons: 0,
    gpos:  0,
    init:  xlcdinit,
    clear: xlcdclear,
    put:   xlcdput,
    bar:   xlcdbar,
    icon:  xlcdicon,
    gpo:   NULL,
    flush: xlcdflush,
    quit:  xlcdquit 
  },
  { NULL }
};