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/*
* NAME
* pkin.c - implementation of readchar()
* DESCRIPTION
* This implementation of readchar() uses parts of the program dvips
* written by Tomas Rokicki--the inventor of the pkformat--(loadfont.c,
* download.c and unpack.c). Dvips in turn is derived from pktype.
* Pktype(TeX) is described in debt in ``The PKtype processor'',
* which is available as pktype.weave as part of the METAFONTware.
* What was needed to implement readchar() is rearranged in pkfile.c to
* get more modularity in the style of MODULA2.
* REDESIGN
* Piet Tutelaers
* rcpt@urc.tue.nl
*/
#ifdef DEBUG
#include <stdio.h>
#endif
#ifdef MSDOS
#define RB "rb"
#else
#define RB "r"
#endif
#include "pkin.h"
/*
* External function
*/
char *malloc();
/*
* Forward declaration
*/
static void error();
/*
* Now we have some routines to get stuff from the pk file. pkbyte returns
* the next byte from the pk file.
*/
static FILE *pkfile ;
static shalfword
pkbyte()
{
register shalfword i ;
if ((i=getc(pkfile))==EOF)
error("! unexpected eof in pk file") ;
return(i) ;
}
static integer
pkquad()
{
register integer i ;
i = pkbyte() ;
if (i > 127)
i -= 256 ;
i = i * 256 + pkbyte() ;
i = i * 256 + pkbyte() ;
i = i * 256 + pkbyte() ;
return(i) ;
}
static integer
pktrio()
{
register integer i ;
i = pkbyte() ;
i = i * 256 + pkbyte() ;
i = i * 256 + pkbyte() ;
return(i) ;
}
static integer
pklong()
{
register integer i ;
i = pkquad() ;
i = i * 65536 + pkquad() ;
return(i) ;
}
static char errbuf[80] ;
/*
* pkopen opens the pk file. This is system dependent.
*/
static Boolean
pkopen(name)
char name[] ;
{
if ((pkfile=fopen(name, RB))==NULL) {
(void)sprintf(errbuf, "Could not open %s", name) ;
error(errbuf) ;
return(0) ;
} else
return(1) ;
}
/*
* The next part is devoted to unpacking the character data.
*/
/*
* We need procedures to get a nybble, bit, and packed word from the
* packed data structure.
*/
static halfword inputbyte, flagbyte ;
static halfword bitweight ;
static halfword dynf ;
static halfword repeatcount ;
static shalfword
getnyb ()
{ halfword temp;
if ( bitweight == 0 )
{ bitweight = 16 ;
inputbyte = pkbyte();
temp = inputbyte >> 4 ;
} else {
bitweight = 0 ;
temp = inputbyte & 15 ;
}
return(temp);
}
static Boolean
getbit ()
{
bitweight >>= 1 ;
if ( bitweight == 0 )
{ inputbyte = pkbyte();
bitweight = 128 ;
}
return(inputbyte & bitweight) ;
}
static halfword (*realfunc)() ;
long remainder ;
static halfword handlehuge() ;
static halfword pkpackednum () {
register halfword i, j ;
i = getnyb () ;
if ( i == 0 )
{ do { j = getnyb () ;
i++ ;
} while ( ! ( j != 0 ) ) ;
if ( i > 3 ) {
/*
* Damn, we got a huge count! We *fake* it by giving an artificially
* large repeat count.
*/
return( handlehuge ( i , j ) ) ;
} else {
while ( i > 0 )
{ j = j * 16 + getnyb () ;
i-- ;
}
return ( j - 15 + ( 13 - dynf ) * 16 + dynf ) ;
}
}
else if ( i <= dynf ) return ( i ) ;
else if ( i < 14 ) return ( ( i - dynf - 1 ) * 16 + getnyb () + dynf + 1
) ;
else
{ if ( i == 14 ) repeatcount = pkpackednum () ;
else repeatcount = 1 ;
#ifdef DEBUG
printf("[%d]", repeatcount);
#endif
return ( (*realfunc)() ) ;
}
}
static halfword rest ()
{
halfword i ;
if (remainder < 0) {
remainder = - remainder ;
return ( 0 ) ;
} else if (remainder > 0) {
if (remainder > 4000) {
remainder = 4000 - remainder ;
return ( 4000 ) ;
} else {
i = remainder ;
remainder = 0 ;
realfunc = pkpackednum ;
return ( i ) ;
}
} else {
error("! shouldn't happen") ;
}
/*NOTREACHED*/
}
static halfword handlehuge ( i , k )
halfword i , k ;
{
register long j = k ;
while (i) {
j = (j << 4L) + getnyb() ;
i-- ;
}
remainder = j - 15 + ( 13 - dynf ) * 16 + dynf ;
realfunc = rest ;
return ( rest() ) ;
}
/*
* And now we have our unpacking routine.
*/
static halfword gpower[17] = { 0 , 1 , 3 , 7 , 15 , 31 , 63 , 127 ,
255 , 511 , 1023 , 2047 , 4095 , 8191 , 16383 , 32767 , 65535 } ;
static void
unpack(cd)
chardesc *cd;
{
register integer i, j ;
register halfword word, wordweight ;
halfword *raster;
shalfword rowsleft ;
Boolean turnon ;
shalfword hbit ;
halfword count ;
shalfword wordwidth ;
wordwidth = (cd->cwidth + 15) / 16 ;
i = 2 * cd->cheight * (long)wordwidth ;
if (i <= 0)
i = 2 ;
cd->raster = (halfword *)malloc((unsigned)i) ;
if (cd->raster == NULL)
error("! out of memory during allocation") ;
raster = cd->raster;
realfunc = pkpackednum ;
dynf = flagbyte / 16 ;
turnon = flagbyte & 8 ;
if ( dynf == 14 )
{ bitweight = 0 ;
for ( i = 1 ; i <= cd->cheight ; i ++ )
{ word = 0 ;
wordweight = 32768 ;
for ( j = 1 ; j <= cd->cwidth ; j ++ )
{ if ( getbit () ) word += wordweight ;
wordweight >>= 1 ;
if ( wordweight == 0 )
{ *raster++ = word ;
word = 0 ;
wordweight = 32768 ;
}
}
if ( wordweight != 32768 )
*raster++ = word ;
}
} else {
rowsleft = cd->cheight ;
hbit = cd->cwidth ;
repeatcount = 0 ;
wordweight = 16 ;
word = 0 ;
bitweight = 0 ;
while ( rowsleft > 0 )
{ count = (*realfunc)() ;
#ifdef DEBUG
if (turnon) printf("(%d) ",count);
else printf("%d ",count);
#endif
while ( count != 0 )
{ if ( ( count < wordweight ) && ( count < hbit ) )
{ if ( turnon ) word += gpower [ wordweight ] - gpower
[ wordweight - count ] ;
hbit -= count ;
wordweight -= count ;
count = 0 ;
}
else if ( ( count >= hbit ) && ( hbit <= wordweight ) )
{ if ( turnon )
word += gpower [ wordweight ] - gpower
[ wordweight - hbit ] ;
*raster++ = word ;
for ( i = 1 ; i <= repeatcount ; i ++ ) {
for ( j = 1 ; j <= wordwidth ; j ++ ) {
*raster = *(raster - wordwidth) ;
raster++ ;
}
}
rowsleft -= repeatcount + 1 ;
repeatcount = 0 ;
word = 0 ;
wordweight = 16 ;
count -= hbit ;
hbit = cd->cwidth ;
}
else
{ if ( turnon ) word += gpower [ wordweight ] ;
*raster++ = word ;
word = 0 ;
count -= wordweight ;
hbit -= wordweight ;
wordweight = 16 ;
}
}
turnon = ! turnon ;
}
putchar('\n') ;
if ( ( rowsleft != 0 ) || ( hbit != cd->cwidth ) )
error ( "! error while unpacking; more bits than required" ) ;
}
}
/*
* readchar(): the main routine
* Reads the character definition of character `c' into `cd' if available,
* return FALSE (0) otherwise.
*/
int
readchar(name, c, cd)
char name[];
shalfword c;
chardesc *cd;
{
register shalfword i ;
register integer k ;
register integer length ;
if (!pkopen(name)) return(0);
/*
* Check the preamble of the pkfile
*/
if (pkbyte()!=247)
error("! bad pk file, expected pre") ;
if (pkbyte()!=89)
error("! bad version of pk file") ;
for(i=pkbyte(); i>0; i--) /* creator of pkfile */
(void)pkbyte() ;
(void)pkquad(); /* design size */
k = pkquad() ; /* checksum */
k = pkquad() ; /* hppp */
k = pkquad() ; /* vppp */
/*
* Now we skip to the desired character definition
*/
while ((flagbyte=pkbyte())!=245) {
if (flagbyte < 240) {
switch (flagbyte & 7) {
case 0: case 1: case 2: case 3:
length = (flagbyte & 7) * 256 + pkbyte() - 4 ;
cd->charcode = pkbyte() ;
(void) pktrio() ; /* TFMwidth */
(void) pkbyte() ; /* pixel width */
break ;
case 4:
length = pkbyte() * 256 ;
length = length + pkbyte() - 5 ;
cd->charcode = pkbyte() ;
(void) pktrio() ; /* TFMwidth */
i = pkbyte() ;
i = i * 256 + pkbyte() ; /* pixelwidth */
break ;
case 5: case 6:
error("! lost sync in pk file (character too big)") ;
case 7:
length = pkquad() - 12 ;
cd->charcode = pkquad() ;
(void) pkquad() ; /* TFMwidth */
/* cd->pixelwidth = (pkquad() + 32768) >> 16 ; */
(void) pkquad(); /* pixelwidth */
k = pkquad() ;
}
if (cd->charcode == c) {
if (flagbyte & 4) {
if ((flagbyte & 7) == 7) { /* long format */
cd->cwidth = pklong() ;
cd->cheight = pklong() ;
cd->xoff = pklong() ;
cd->yoff = pklong() ;
} else { /* extended format */
cd->cwidth = pkquad(); ;
cd->cheight = pkquad() ;
cd->xoff = pkquad() ;
cd->yoff = pkquad() ;
}
} else { /* short format */
cd->cwidth = pkbyte() ;
cd->cheight = pkbyte() ;
cd->xoff = pkbyte() ;
cd->yoff = pkbyte() ;
if (cd->xoff > 127)
cd->xoff -= 256 ;
if (cd->yoff > 127)
cd->yoff -= 256 ;
}
unpack(cd);
(void)fclose(pkfile) ;
return(1);
}
for (; length>0; length--) /* skip this character */
(void) pkbyte() ;
} else {
k = 0 ;
switch (flagbyte) {
case 243:
k = pkbyte() ;
if (k > 127)
k -= 256 ;
case 242:
k = k * 256 + pkbyte() ;
case 241:
k = k * 256 + pkbyte() ;
case 240:
k = k * 256 + pkbyte() ;
while (k-- > 0)
i = pkbyte() ;
break ;
case 244:
k = pkquad() ;
break ;
case 246:
break ;
default:
error("! lost sync in pk file") ;
}
}
}
(void)fclose(pkfile) ;
return(0); /* character not found */
}
static void error(s)
char s[];
{
fprintf(stderr, "%s\n", s);
exit(1);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.