summaryrefslogtreecommitdiff
path: root/Build/source/texk/ps2pk/pkin.c
blob: be295a00b48658c9a29c74dc2dba1a4ba51bc8db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
/*
 * 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
 */

#ifdef HAVE_CONFIG_H
#include "c-auto.h"
#endif

#ifdef DEBUG
#include <stdio.h>
#endif

#include <stdlib.h>	/* malloc() */
#include "basics.h"	/* basic definitions */
#include "pkin.h"

/*
 *   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(void)
{
   register shalfword i ;

   if ((i=getc(pkfile))==EOF)
      fatal("unexpected eof in pk file\n") ;
   return(i) ;
}

static shalfword
pksbyte(void)
{
   register shalfword i ;

   i = pkbyte() ;
   return i > 127 ? i -256 : i ;
}

static integer
pkquad(void)
{
   register integer i ;

   i = pksbyte() ;
   i = i * 256 + pkbyte() ;
   i = i * 256 + pkbyte() ;
   i = i * 256 + pkbyte() ;
   return(i) ;
}

static integer
pktrio(void)
{
   register integer i ;

   i = pkbyte() ;
   i = i * 256 + pkbyte() ;
   i = i * 256 + pkbyte() ;
   return(i) ;
}

static integer
pkpair(void)
{
  register integer i ;
  
  i = pkbyte() ;
  i = i * 256 + pkbyte() ;
  return (i);
}

static integer
pkspair(void)
{
  register integer i ;
  
  i = pksbyte() ;
  i = i * 256 + pkbyte();
  return (i);
}

/*
 *   pkopen opens the pk file.  This is system dependent.
 */

static Boolean	
pkopen(const char *name)
{
   if ((pkfile=fopen(name, RB))==NULL) {
      fatal("Could not open %s\n", name) ;
   } 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 (void)
{   halfword temp;
    if ( bitweight == 0 ) 
    { bitweight = 16 ; 
      inputbyte = pkbyte();
      temp = inputbyte >> 4 ;
    } else {
      bitweight = 0 ;
      temp = inputbyte & 15 ;
    }
    return(temp);
} 

static Boolean
getbit (void)
{
    bitweight >>= 1 ; 
    if ( bitweight == 0 ) 
    { inputbyte = pkbyte();
      bitweight = 128 ;
    } 
    return(inputbyte & bitweight) ;
}

static halfword (*realfunc)() ;
long PKremainder ;
static halfword handlehuge(halfword i, halfword k) ;

static halfword
pkpackednum (void)
{
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 (void)
{
   halfword i ;

   if (PKremainder < 0) {
      PKremainder = - PKremainder ;
      return ( 0 ) ;
   } else if (PKremainder > 0) {
      if (PKremainder > 4000) {
         PKremainder = 4000 - PKremainder ;
         return ( 4000 ) ;
      } else {
         i = PKremainder ;
         PKremainder = 0 ;
         realfunc = pkpackednum ;
         return ( i ) ;
      }
   } else {
      fatal("shouldn't happen\n") ;
   }

   /*NOTREACHED*/
   return 0;
}

static halfword
handlehuge (halfword i, halfword k)
{
   register long j = k ;

   while (i) {
      j = (j << 4L) + getnyb() ;
      i-- ;
   }
   PKremainder = 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(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)
         fatal("out of memory during allocation\n") ;
      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 ) ) 
              fatal( "error while unpacking; more bits than required\n" ) ; 
        } 
}

/*
 *   readchar(): the main routine
 *   Reads the character definition of character `c' into `cd' if available,
 *   return FALSE (0) otherwise.
 */
int
readchar(char *name, integer c, chardesc *cd)
{
   register shalfword i ;
   register integer k ;
   register integer length = 0;

   if (!pkopen(name)) return(0);
/*
 *   Check the preamble of the pkfile
 */
   if (pkbyte()!=247)
      fatal("bad pk file, expected pre\n") ;
   if (pkbyte()!=89)
      fatal("bad version of pk file\n") ;
   for(i=pkbyte(); i>0; i--)	/* creator of pkfile */
      (void)pkbyte() ; 		
   (void) pkquad() ;  /* design size */
   (void) pkquad() ;  /* checksum    */
   (void) pkquad() ;  /* hppp        */
   (void) 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: case 5: case 6:
            length = (flagbyte & 3) * 65536 + pkpair() * 256 - 5 ;
            cd->charcode = pkbyte() ;
            (void) pktrio() ;		/* TFMwidth */
            (void) pkpair() ;           /* pixelwidth */
            break ;
case 7:
            length = pkquad() - 12 ;
            cd->charcode = pkquad() ;
            (void) pkquad() ;		/* TFMwidth */
	    (void) pkquad();		/* pixelwidth */
	    (void) pkquad();		/* pixelheight */
         }
         if (length <= 0)
            fatal("packet length (%d) too small\n", length) ;
         if (cd->charcode == c) {
            if (flagbyte & 4) {
               if ((flagbyte & 7) == 7) { /* long format */
                  cd->cwidth = pkquad() ;
                  cd->cheight = pkquad() ;
                  cd->xoff = pkquad() ;
                  cd->yoff = pkquad() ;
               } else { /* extended format */
                  cd->cwidth = pkpair(); ;
                  cd->cheight = pkpair() ;
                  cd->xoff = pkspair() ;
                  cd->yoff = pkspair() ;
               }
            } else { /* short format */
               cd->cwidth = pkbyte() ;
               cd->cheight = pkbyte() ;
               cd->xoff = pksbyte() ;
               cd->yoff = pksbyte() ;
            }
            unpack(cd);
            (void)fclose(pkfile) ;
            return(1);
         }
         for (; length>0; length--) /* skip this character */
            (void) pkbyte() ;
      } else {
         k = 0 ;
         switch (flagbyte) {
case 243:
            k = pksbyte() ;
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:
            fatal("unexpected command (%d)\n", flagbyte) ;
         }
      }
   }
   (void)fclose(pkfile) ;
   return(0); /* character not found */
}