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-rw-r--r--Build/source/texk/dvipsk/repack.c448
1 files changed, 448 insertions, 0 deletions
diff --git a/Build/source/texk/dvipsk/repack.c b/Build/source/texk/dvipsk/repack.c
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+/*
+ * Compressed TeX fonts in PostScript.
+ * By Radical Eye Software.
+ * (Slight mods by Don Knuth in December 89.)
+ */
+#include "dvips.h" /* The copyright notice in that file is included too! */
+/*
+ * The external declarations:
+ */
+#include "protos.h"
+
+/* Given a raster that has been unpacked from PK format,
+ * we compress it by another scheme that is suitable for
+ * a PostScript-oriented unpacking. We write instructions for
+ * a little interpreter whose one-byte instructions have the form
+ * 18*opcode+parameter. The interpreter forms each row based
+ * on simple transformations to the previous row. */
+
+#define MAXOUT (18)
+#define CMD(n) (MAXOUT*(n))
+#define ADVXCHG1 CMD(0)
+#define ADVXCHG1END CMD(1)
+#define CHGX CMD(2)-1
+#define CHGXEND CMD(3)-1
+#define ADVXLSH CMD(4)
+#define ADVXLSHEND CMD(5)
+#define ADVXRSH CMD(6)
+#define ADVXRSHEND CMD(7)
+#define ADVX CMD(8)-1
+#define REPX CMD(9)-1
+#define SETX CMD(10)-1
+#define CLRX CMD(11)-1
+#define ADVXCHG2 CMD(12)
+#define ADVXCHG2END CMD(13)
+#define END CMD(14)
+
+static int rowlength = -1;
+static unsigned char *specdata;
+static long tslen = 0;
+static unsigned char *tempstore, *tsp, *tsend;
+
+static void
+putlong(register char *a, long i)
+{
+ a[0] = i >> 24;
+ a[1] = i >> 16;
+ a[2] = i >> 8;
+ a[3] = i;
+}
+
+long
+getlong(register unsigned char *a)
+{
+ return ((((((a[0] << 8L) + a[1]) << 8L) + a[2]) << 8L) + a[3]);
+}
+
+/* First, a routine that appends one byte to the compressed output. */
+
+#define addtse(n) {lcm=tsp-tempstore;addts(n);} /* mark END option position */
+
+static void
+addts(register unsigned char what)
+{
+ register unsigned char *p, *q;
+
+ if (tsp >= tsend) {
+ if (tempstore == NULL) {
+ tslen = 2020;
+ tempstore = (unsigned char *)mymalloc((integer)tslen);
+ tsp = tempstore;
+ } else {
+ tslen = 2 * tslen;
+ tsp = (unsigned char *)mymalloc((integer)tslen);
+ for (p=tempstore, q=tsp; p<tsend; p++, q++)
+ *q = *p;
+ free((char *)tempstore);
+ tempstore = tsp;
+ tsp = q;
+ }
+ tsend = tempstore + tslen;
+ }
+ *tsp++ = what;
+}
+
+/* Next, a routine that discovers how to do the compression. */
+
+#define rsh(a,b) ( ((a)==0) ? ((b)==128) : ( ((a)==255) ? ((b)==127) :\
+ ((b)==(((a)>>1)|((a)&128))) ))
+#define lsh(a,b) ( ((a)==0) ? ((b)==1) : ( ((a)==255) ? ((b)==254) :\
+ ((b)==((((a)<<1)&255)|((a)&1))) ))
+#define DIFFERENT (1)
+#define LSHPOSSIB (2)
+#define RSHPOSSIB (4)
+#define BLKPOSSIB (8)
+#define WHTPOSSIB (16)
+#define ENDROW (32)
+#define NOPOSSIB(n) ((n&(LSHPOSSIB|RSHPOSSIB|BLKPOSSIB|WHTPOSSIB))==0)
+#define NOSHIFT(n) ((n&(LSHPOSSIB|RSHPOSSIB))==0)
+/*
+ * Our input bytes are packed to the 16-bit word. On output,
+ * they're packed to bytes. Thus, we may have to skip a byte at
+ * the end of each row.
+ */
+void
+dochar(unsigned char *from, short width, short height)
+{
+ register int i;
+ register unsigned char *f, *t, *d;
+ register unsigned char *e;
+ register int accum;
+ int j, k, kk;
+ int diffrow;
+ int repeatcount;
+ int lit, pos, cmd = 0;
+ long lcm;
+ int widthc;
+
+ widthc = width + (width & 1); /* halfword correction */
+ lcm = -1;
+ if (widthc > rowlength) {
+ if (rowlength > 0)
+ free((char *)specdata);
+ rowlength = widthc + 30;
+ specdata = (unsigned char *)mymalloc((integer)(rowlength + 15));
+ }
+ for (i= -15, t=specdata; i<=widthc; i++, t++)
+ *t = 0;
+ repeatcount = 0;
+ f = specdata + 2;
+ for (j=0; j<height; j++, f = from, from += widthc) {
+ diffrow = 0;
+ for (i=0, t=from, d=specdata; i<width; i++, f++, t++, d++) {
+ if (*f == *t) {
+ if (*t == 0)
+ *d = WHTPOSSIB;
+ else if (*t == 255)
+ *d = BLKPOSSIB;
+ else
+ *d = 0;
+ } else {
+ accum = DIFFERENT;
+ if (rsh(*f, *t))
+ accum |= RSHPOSSIB;
+ else if (lsh(*f, *t))
+ accum |= LSHPOSSIB;
+ if (*t == 0)
+ accum |= WHTPOSSIB;
+ else if (*t == 255)
+ accum |= BLKPOSSIB;
+ *d = accum;
+ diffrow++;
+ }
+ } /* end 'for i' */
+ *d = ENDROW;
+ if (diffrow == 0) {
+ repeatcount++;
+ } else {
+ if (repeatcount) {
+ while (repeatcount > MAXOUT) {
+ addts((unsigned char)(REPX+MAXOUT));
+ repeatcount -= MAXOUT;
+ }
+ addts((unsigned char)(REPX+repeatcount));
+ repeatcount = 0;
+ }
+ pos = 0;
+ for (i=0, d=specdata, f=t-width; i<width;) {
+ if ((*d & DIFFERENT) == 0) {
+ i++;
+ d++;
+ f++;
+ } else {
+ accum = 0;
+ if (pos != i)
+ lit = NOSHIFT(*d);
+ else /* N.B.: 'lit' does not imply literate programming here */
+ lit = NOPOSSIB(*d);
+ for (e=d;;e++) {
+ if (NOPOSSIB(*e))
+ lit = 1;
+ if ((*e & DIFFERENT) == 0)
+ break;
+ if ((*e & WHTPOSSIB) &&
+ (e[1] & WHTPOSSIB)) {
+ while (*e & WHTPOSSIB) {
+ e++;
+ accum++;
+ }
+ cmd = CLRX;
+ e -= accum;
+ break;
+ } else if ((*e & BLKPOSSIB) &&
+ (e[1] & BLKPOSSIB)) {
+ while (*e & BLKPOSSIB) {
+ e++;
+ accum++;
+ }
+ cmd = SETX;
+ e -= accum;
+ break;
+ }
+ } /* end 'for e'; d pts to first bad byte, e to next good one */
+ while (i - pos > MAXOUT) {
+ addts((unsigned char)(ADVX+MAXOUT));
+ pos += MAXOUT;
+ }
+ if (0 != (k = (e - d))) {
+ if (lit) {
+ if (k > 2) {
+ if (i > pos) {
+ addts((unsigned char)(ADVX + i - pos));
+ pos = i;
+ }
+ while (k > MAXOUT) {
+ addts((unsigned char)(CHGX + MAXOUT));
+ for (kk=0; kk<MAXOUT; kk++)
+ addts((unsigned char)(*f++));
+ d += MAXOUT;
+ pos += MAXOUT;
+ i += MAXOUT;
+ k -= MAXOUT;
+ }
+ addtse((unsigned char)(CHGX + k));
+ pos += k;
+ for (; d<e; d++, i++, f++)
+ addts((unsigned char)(*f));
+ } else {
+ if (k == 1) {
+ if (i == pos+MAXOUT) {
+ addts((unsigned char)(ADVX + MAXOUT));
+ pos = i;
+ }
+ addtse((unsigned char)(ADVXCHG1 + i - pos));
+ addts((unsigned char)(*f));
+ i++;
+ pos = i;
+ d++;
+ f++;
+ } else {
+ if (i == pos+MAXOUT) {
+ addts((unsigned char)(ADVX + MAXOUT));
+ pos = i;
+ }
+ addtse((unsigned char)(ADVXCHG2 + i - pos));
+ addts((unsigned char)(*f));
+ addts((unsigned char)(f[1]));
+ i += 2;
+ pos = i;
+ d += 2;
+ f += 2;
+ }
+ }
+ } else {
+ while (e > d) {
+ if (*d & LSHPOSSIB) {
+ if (i == pos+MAXOUT) {
+ addts((unsigned char)(ADVX + MAXOUT));
+ pos = i;
+ }
+ addtse((unsigned char)(ADVXLSH + i - pos));
+ } else if (*d & RSHPOSSIB) {
+ if (i == pos+MAXOUT) {
+ addts((unsigned char)(ADVX + MAXOUT));
+ pos = i;
+ }
+ addtse((unsigned char)(ADVXRSH + i - pos));
+ } else if (*d & WHTPOSSIB) { /* i==pos */
+ addts((unsigned char)(CLRX + 1)); lcm = -1;
+ } else if (*d & BLKPOSSIB) { /* i==pos */
+ addts((unsigned char)(SETX + 1)); lcm = -1;
+ } else
+ error("! bug"); /* why wasn't lit true? */
+ d++;
+ f++;
+ i++;
+ pos = i;
+ } /* end 'while e>d' */
+ }
+ } /* end 'if e>d' */
+ if (accum > 0) {
+ if (i > pos) {
+ addts((unsigned char)(ADVX + i - pos));
+ pos = i;
+ }
+ i += accum;
+ d += accum;
+ f += accum;
+ while (accum > MAXOUT) {
+ addts((unsigned char)(cmd + MAXOUT));
+ accum -= MAXOUT;
+ pos += MAXOUT;
+ }
+ lcm = -1;
+ addts((unsigned char)(cmd + accum));
+ pos += accum;
+ }
+ } /* end 'else DIFFERENT' */
+ } /* end 'for i' */
+ if (lcm != -1) {
+ tempstore[lcm] += MAXOUT; /* append END */
+ lcm = -1;
+ } else {
+ addts((unsigned char)(END));
+ }
+ } /* end 'else rows different' */
+#ifdef DEBUG
+ if (d != specdata + width)
+ error("! internal inconsistency in repack");
+#endif
+ } /* end 'for j' */
+ if (repeatcount) {
+ while (repeatcount > MAXOUT) {
+ addts((unsigned char)(REPX+MAXOUT));
+ repeatcount -= MAXOUT;
+ }
+ addts((unsigned char)(REPX+repeatcount));
+ repeatcount = 0;
+ }
+}
+
+long mbytesleft;
+quarterword *mraster;
+
+static char *
+makecopy(register unsigned char *what,
+ register long len,
+ register unsigned char *p)
+{
+ register unsigned char *q;
+
+ if (p == NULL) {
+ if (len > MINCHUNK)
+ p = (unsigned char *)mymalloc((integer)len);
+ else {
+ if (bytesleft < len) {
+ raster = (quarterword *)mymalloc((integer)RASTERCHUNK);
+ bytesleft = RASTERCHUNK;
+ }
+ p = (unsigned char *)raster;
+ bytesleft -= len;
+ raster += len;
+ }
+ }
+ q = p;
+ while (len > 0) {
+ *p++ = *what++;
+ len --;
+ }
+ return ((char *)q);
+}
+
+/* Now the main routine, which is called when a character is used
+ for the very first time. */
+void
+repack(register chardesctype *cp)
+{
+ register long i, j;
+ register unsigned char *p;
+ register int width, height;
+ register int wwidth;
+ char startbytes;
+ int smallchar;
+
+ p = cp->packptr;
+ if (p == NULL)
+ error("! no raster?");
+ tsp = tempstore;
+ tsend = tempstore + tslen;
+ addts(*p); /* copy the PK flag byte */
+ if (*p & 4) {
+ if ((*p & 7) == 7) {
+ startbytes = 17;
+ width = getlong(p + 1);
+ height = getlong(p + 5);
+ for (i=0; i<12; i++)
+ addts(*++p);
+ } else {
+ startbytes = 9;
+ width = p[1] * 256 + p[2];
+ height = p[3] * 256 + p[4];
+ addts(*++p);
+ addts(*++p);
+ addts(*++p);
+ addts(*++p);
+ }
+ } else {
+ startbytes = 5;
+ width = p[1];
+ height = p[2];
+ }
+ addts(*++p);
+ addts(*++p);
+ addts(*++p);
+ addts(*++p);
+ p++; /* OK, p now points to beginning of the nibbles */
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ addts((unsigned char)0); /* leave room to stick in a new length field */
+ wwidth = (width + 15) / 16;
+ i = 2 * height * (long)wwidth;
+ if (i <= 0)
+ i = 2;
+ if ((cp->flags & BIGCHAR) == 0)
+ smallchar = 5;
+ else
+ smallchar = 0;
+ i += smallchar;
+ if (mbytesleft < i) {
+ if (mbytesleft >= RASTERCHUNK)
+ (void) free((char *) mraster);
+ if (RASTERCHUNK > i) {
+ mraster = (quarterword *)mymalloc((integer)RASTERCHUNK);
+ mbytesleft = RASTERCHUNK;
+ } else {
+ i += i / 4;
+ mraster = (quarterword *)mymalloc((integer)(i + 3));
+ mbytesleft = i;
+ }
+ }
+ while (i > 0)
+ mraster[--i] = 0;
+ i = startbytes + unpack(p, (halfword *)mraster, (halfword)width,
+ (halfword)height, *(cp->packptr));
+ dochar(mraster, (short)((width + 7) >> 3), (short)height);
+ if (smallchar) {
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ addts((unsigned char)0);
+ }
+ j = tsp - tempstore;
+#ifdef DEBUG
+ if (dd(D_COMPRESS))
+ fprintf(stderr,"PK %ld bytes, unpacked %ld, compressed %ld\n",
+ i-(long)startbytes, (long)((width+7L)/8)*height, j-(long)startbytes-4);
+#endif /* DEBUG */
+ if ( i < j ) {
+ if (i > MINCHUNK)
+ free(cp->packptr);
+ cp->packptr =
+ (unsigned char *)makecopy(tempstore, j, (unsigned char *)0);
+ } else
+ makecopy(tempstore, j, (unsigned char *)cp->packptr);
+ putlong((char *)(cp->packptr+startbytes), j-startbytes-4-smallchar);
+ cp->flags |= REPACKED;
+}