zint/backend/dm200.c

/** 
 *
 * IEC16022 bar code generation
 * Adrian Kennard, Andrews & Arnold Ltd
 * with help from Cliff Hones on the RS coding
 * 
 * (c) 2004 Adrian Kennard, Andrews & Arnold Ltd
 * (c) 2006 Stefan Schmidt <stefan@datenfreihafen.org>
 * 
 * This program 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 of the License, or
 * (at your option) any later version.
 *
 * This program 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include "reedsol.h"
#include "dm200.h"

static struct ecc200matrix_s {
	int H, W;
	int FH, FW;
	int bytes;
	int datablock, rsblock;
} ecc200matrix[] = {
	10, 10, 10, 10, 3, 3, 5,	//
	    12, 12, 12, 12, 5, 5, 7,	//
	    8, 18, 8, 18, 5, 5, 7,	//
	    14, 14, 14, 14, 8, 8, 10,	//
	    8, 32, 8, 16, 10, 10, 11,	//
	    16, 16, 16, 16, 12, 12, 12,	//
	    12, 26, 12, 26, 16, 16, 14,	//
	    18, 18, 18, 18, 18, 18, 14,	//
	    20, 20, 20, 20, 22, 22, 18,	//
	    12, 36, 12, 18, 22, 22, 18,	//
	    22, 22, 22, 22, 30, 30, 20,	//
	    16, 36, 16, 18, 32, 32, 24,	//
	    24, 24, 24, 24, 36, 36, 24,	//
	    26, 26, 26, 26, 44, 44, 28,	//
	    16, 48, 16, 24, 49, 49, 28,	//
	    32, 32, 16, 16, 62, 62, 36,	//
	    36, 36, 18, 18, 86, 86, 42,	//
	    40, 40, 20, 20, 114, 114, 48,	//
	    44, 44, 22, 22, 144, 144, 56,	//
	    48, 48, 24, 24, 174, 174, 68,	//
	    52, 52, 26, 26, 204, 102, 42,	//
	    64, 64, 16, 16, 280, 140, 56,	//
	    72, 72, 18, 18, 368, 92, 36,	//
	    80, 80, 20, 20, 456, 114, 48,	//
	    88, 88, 22, 22, 576, 144, 56,	//
	    96, 96, 24, 24, 696, 174, 68,	//
	    104, 104, 26, 26, 816, 136, 56,	//
	    120, 120, 20, 20, 1050, 175, 68,	//
	    132, 132, 22, 22, 1304, 163, 62,	//
	    144, 144, 24, 24, 1558, 156, 62,	// 156*4+155*2
	    0			// terminate
};

 // simple checked response malloc
static void *safemalloc(int n)
{
	void *p = malloc(n);
	if (!p) {
		fprintf(stderr, "Malloc(%d) failed\n", n);
		exit(1);
	}
	return p;
}

// Annex M placement alorithm low level
static void ecc200placementbit(int *array, int NR, int NC, int r, int c,
			       int p, char b)
{
	if (r < 0) {
		r += NR;
		c += 4 - ((NR + 4) % 8);
	}
	if (c < 0) {
		c += NC;
		r += 4 - ((NC + 4) % 8);
	}
	array[r * NC + c] = (p << 3) + b;
}

static void ecc200placementblock(int *array, int NR, int NC, int r,
				 int c, int p)
{
	ecc200placementbit(array, NR, NC, r - 2, c - 2, p, 7);
	ecc200placementbit(array, NR, NC, r - 2, c - 1, p, 6);
	ecc200placementbit(array, NR, NC, r - 1, c - 2, p, 5);
	ecc200placementbit(array, NR, NC, r - 1, c - 1, p, 4);
	ecc200placementbit(array, NR, NC, r - 1, c - 0, p, 3);
	ecc200placementbit(array, NR, NC, r - 0, c - 2, p, 2);
	ecc200placementbit(array, NR, NC, r - 0, c - 1, p, 1);
	ecc200placementbit(array, NR, NC, r - 0, c - 0, p, 0);
}

static void ecc200placementcornerA(int *array, int NR, int NC, int p)
{
	ecc200placementbit(array, NR, NC, NR - 1, 0, p, 7);
	ecc200placementbit(array, NR, NC, NR - 1, 1, p, 6);
	ecc200placementbit(array, NR, NC, NR - 1, 2, p, 5);
	ecc200placementbit(array, NR, NC, 0, NC - 2, p, 4);
	ecc200placementbit(array, NR, NC, 0, NC - 1, p, 3);
	ecc200placementbit(array, NR, NC, 1, NC - 1, p, 2);
	ecc200placementbit(array, NR, NC, 2, NC - 1, p, 1);
	ecc200placementbit(array, NR, NC, 3, NC - 1, p, 0);
}

static void ecc200placementcornerB(int *array, int NR, int NC, int p)
{
	ecc200placementbit(array, NR, NC, NR - 3, 0, p, 7);
	ecc200placementbit(array, NR, NC, NR - 2, 0, p, 6);
	ecc200placementbit(array, NR, NC, NR - 1, 0, p, 5);
	ecc200placementbit(array, NR, NC, 0, NC - 4, p, 4);
	ecc200placementbit(array, NR, NC, 0, NC - 3, p, 3);
	ecc200placementbit(array, NR, NC, 0, NC - 2, p, 2);
	ecc200placementbit(array, NR, NC, 0, NC - 1, p, 1);
	ecc200placementbit(array, NR, NC, 1, NC - 1, p, 0);
}

static void ecc200placementcornerC(int *array, int NR, int NC, int p)
{
	ecc200placementbit(array, NR, NC, NR - 3, 0, p, 7);
	ecc200placementbit(array, NR, NC, NR - 2, 0, p, 6);
	ecc200placementbit(array, NR, NC, NR - 1, 0, p, 5);
	ecc200placementbit(array, NR, NC, 0, NC - 2, p, 4);
	ecc200placementbit(array, NR, NC, 0, NC - 1, p, 3);
	ecc200placementbit(array, NR, NC, 1, NC - 1, p, 2);
	ecc200placementbit(array, NR, NC, 2, NC - 1, p, 1);
	ecc200placementbit(array, NR, NC, 3, NC - 1, p, 0);
}

static void ecc200placementcornerD(int *array, int NR, int NC, int p)
{
	ecc200placementbit(array, NR, NC, NR - 1, 0, p, 7);
	ecc200placementbit(array, NR, NC, NR - 1, NC - 1, p, 6);
	ecc200placementbit(array, NR, NC, 0, NC - 3, p, 5);
	ecc200placementbit(array, NR, NC, 0, NC - 2, p, 4);
	ecc200placementbit(array, NR, NC, 0, NC - 1, p, 3);
	ecc200placementbit(array, NR, NC, 1, NC - 3, p, 2);
	ecc200placementbit(array, NR, NC, 1, NC - 2, p, 1);
	ecc200placementbit(array, NR, NC, 1, NC - 1, p, 0);
}

// Annex M placement alorithm main function
static void ecc200placement(int *array, int NR, int NC)
{
	int r, c, p;
	// invalidate
	for (r = 0; r < NR; r++)
		for (c = 0; c < NC; c++)
			array[r * NC + c] = 0;
	// start
	p = 1;
	r = 4;
	c = 0;
	do {
		// check corner
		if (r == NR && !c)
			ecc200placementcornerA(array, NR, NC, p++);
		if (r == NR - 2 && !c && NC % 4)
			ecc200placementcornerB(array, NR, NC, p++);
		if (r == NR - 2 && !c && (NC % 8) == 4)
			ecc200placementcornerC(array, NR, NC, p++);
		if (r == NR + 4 && c == 2 && !(NC % 8))
			ecc200placementcornerD(array, NR, NC, p++);
		// up/right
		do {
			if (r < NR && c >= 0 && !array[r * NC + c])
				ecc200placementblock(array, NR, NC, r, c, p++);
			r -= 2;
			c += 2;
		}
		while (r >= 0 && c < NC);
		r++;
		c += 3;
		// down/left
		do {
			if (r >= 0 && c < NC && !array[r * NC + c])
				ecc200placementblock(array, NR, NC, r, c, p++);
			r += 2;
			c -= 2;
		}
		while (r < NR && c >= 0);
		r += 3;
		c++;
	}
	while (r < NR || c < NC);
	// unfilled corner
	if (!array[NR * NC - 1])
		array[NR * NC - 1] = array[NR * NC - NC - 2] = 1;
}

// calculate and append ecc code, and if necessary interleave
static void ecc200(unsigned char *binary, int bytes, int datablock, int rsblock)
{
	int blocks = (bytes + 2) / datablock, b;
	rs_init_gf(0x12d);
	rs_init_code(rsblock, 1);
	for (b = 0; b < blocks; b++) {
		unsigned char buf[256], ecc[256];
		int n, p = 0;
		for (n = b; n < bytes; n += blocks)
			buf[p++] = binary[n];
		rs_encode(p, buf, ecc);
		p = rsblock - 1;	// comes back reversed
		for (n = b; n < rsblock * blocks; n += blocks)
			binary[bytes + n] = ecc[p--];
	}
}

/*
 * perform encoding for ecc200, source s len sl, to target t len tl, using 
 * optional encoding control string e return 1 if OK, 0 if failed. Does all 
 * necessary padding to tl
 */

char ecc200encode(unsigned char *t, int tl, unsigned char *s, int sl,
		  char *encoding, int *lenp)
{
	char enc = 'a';		// start in ASCII encoding mode
	int tp = 0, sp = 0;
	if (strlen(encoding) < sl) {
		fprintf(stderr, "Encoding string too short\n");
		return 0;
	}
	// do the encoding
	while (sp < sl && tp < tl) {
		char newenc = enc;	// suggest new encoding
		if (tl - tp <= 1 && (enc == 'c' || enc == 't') || tl - tp <= 2
		    && enc == 'x')
			enc = 'a';	// auto revert to ASCII
		newenc = tolower(encoding[sp]);
		switch (newenc) {	// encode character
		case 'c':	// C40
		case 't':	// Text
		case 'x':	// X12
			{
				char out[6], p = 0;
				const char *e,
				    *s2 = "!\"#$%&'()*+,-./:;<=>?@[\\]_",
				    *s3 = 0;
				if (newenc == 'c') {
					e = " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
					s3 = "`abcdefghijklmnopqrstuvwxyz{|}~\177";
				}
				if (newenc == 't') {
					e = " 0123456789abcdefghijklmnopqrstuvwxyz";
					s3 = "`ABCDEFGHIJKLMNOPQRSTUVWXYZ{|}~\177";
				}
				if (newenc == 'x')
					e = " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ\r*>";
				do {
					unsigned char c = s[sp++];
					char *w;
					if (c & 0x80) {
						if (newenc == 'x') {
							fprintf(stderr,
								"Cannot encode char 0x%02X in X12\n",
								c);
							return 0;
						}
						c &= 0x7f;
						out[p++] = 1;
						out[p++] = 30;
					}
					w = strchr(e, c);
					if (w)
						out[p++] = ((w - e) + 3) % 40;
					else {
						if (newenc == 'x') {
							fprintf(stderr,
								"Cannot encode char 0x%02X in X12\n",
								c);
							return 0;
						}
						if (c < 32) {	// shift 1
							out[p++] = 0;
							out[p++] = c;
						} else {
							w = strchr(s2, c);
							if (w) {	// shift 2
								out[p++] = 1;
								out[p++] =
								    (w - s2);
							} else {
								w = strchr(s3,
									   c);
								if (w) {
									out[p++]
									    = 2;
									out[p++]
									    =
									    (w -
									     s3);
								} else {
									fprintf
									    (stderr,
									     "Could not encode 0x%02X, should \
								   	not happen\n", c);
									return
									    0;
								}
							}
						}
					}
					if (p == 2 && tp + 2 <= tl && sp == sl)
						out[p++] = 0;	// shift 1 pad at end
					while (p >= 3) {
						int v =
						    out[0] * 1600 +
						    out[1] * 40 + out[2] + 1;
						if (enc != newenc) {
							if (enc == 'c'
							    || enc == 't'
							    || enc == 'x')
								t[tp++] = 254;	// escape C40/text/X12
							else if (enc == 'x')
								t[tp++] = 0x7C;	// escape EDIFACT
							if (newenc == 'c')
								t[tp++] = 230;
							if (newenc == 't')
								t[tp++] = 239;
							if (newenc == 'x')
								t[tp++] = 238;
							enc = newenc;
						}
						t[tp++] = (v >> 8);
						t[tp++] = (v & 0xFF);
						p -= 3;
						out[0] = out[3];
						out[1] = out[4];
						out[2] = out[5];
					}
				}
				while (p && sp < sl);
			}
			break;
		case 'e':	// EDIFACT
			{
				unsigned char out[4], p = 0;
				if (enc != newenc) {	// can only be from C40/Text/X12
					t[tp++] = 254;
					enc = 'a';
				}
				while (sp < sl && tolower(encoding[sp]) == 'e'
				       && p < 4)
					out[p++] = s[sp++];
				if (p < 4) {
					out[p++] = 0x1F;
					enc = 'a';
				}	// termination
				t[tp] = ((s[0] & 0x3F) << 2);
				t[tp++] |= ((s[1] & 0x30) >> 4);
				t[tp] = ((s[1] & 0x0F) << 4);
				if (p == 2)
					tp++;
				else {
					t[tp++] |= ((s[2] & 0x3C) >> 2);
					t[tp] = ((s[2] & 0x03) << 6);
					t[tp++] |= (s[3] & 0x3F);
				}
			}
			break;
		case 'a':	// ASCII
			if (enc != newenc) {
				if (enc == 'c' || enc == 't' || enc == 'x')
					t[tp++] = 254;	// escape C40/text/X12
				else
					t[tp++] = 0x7C;	// escape EDIFACT
			}
			enc = 'a';
			if (sl - sp >= 2 && isdigit(s[sp])
			    && isdigit(s[sp + 1])) {
				t[tp++] =
				    (s[sp] - '0') * 10 + s[sp + 1] - '0' + 130;
				sp += 2;
			} else if (s[sp] > 127) {
				t[tp++] = 235;
				t[tp++] = s[sp++] - 127;
			} else
				t[tp++] = s[sp++] + 1;
			break;
		case 'b':	// Binary
			{
				int l = 0;	// how much to encode
				if (encoding) {
					int p;
					for (p = sp;
					     p < sl
					     && tolower(encoding[p]) == 'b';
					     p++)
						l++;
				}
				t[tp++] = 231;	// base256
				if (l < 250)
					t[tp++] = l;
				else {
					t[tp++] = 249 + (l / 250);
					t[tp++] = (l % 250);
				}
				while (l-- && tp < tl) {
					t[tp] = s[sp++] + (((tp + 1) * 149) % 255) + 1;	// see annex H
					tp++;
				}
				enc = 'a';	// reverse to ASCII at end
			}
			break;
		default:
			fprintf(stderr, "Unknown encoding %c\n", newenc);
			return 0;	// failed
		}
	}
	if (lenp)
		*lenp = tp;
	if (tp < tl && enc != 'a') {
		if (enc == 'c' || enc == 'x' || enc == 't')
			t[tp++] = 254;	// escape X12/C40/Text
		else
			t[tp++] = 0x7C;	// escape EDIFACT
	}
	if (tp < tl)
		t[tp++] = 129;	// pad
	while (tp < tl) {	// more padding
		int v = 129 + (((tp + 1) * 149) % 253) + 1;	// see Annex H
		if (v > 254)
			v -= 254;
		t[tp++] = v;
	}
	if (tp > tl || sp < sl)
		return 0;	// did not fit
	/*
	 * for (tp = 0; tp < tl; tp++) fprintf (stderr, "%02X ", t[tp]); \
	 * fprintf (stderr, "\n");
	 */
	return 1;		// OK 
}

// Auto encoding format functions
static char encchr[] = "ACTXEB";

enum {
	E_ASCII,
	E_C40,
	E_TEXT,
	E_X12,
	E_EDIFACT,
	E_BINARY,
	E_MAX
};

unsigned char switchcost[E_MAX][E_MAX] = {
	0, 1, 1, 1, 1, 2,	// From E_ASCII
	1, 0, 2, 2, 2, 3,	// From E_C40
	1, 2, 0, 2, 2, 3,	// From E_TEXT
	1, 2, 2, 0, 2, 3,	// From E_X12
	1, 2, 2, 2, 0, 3,	// From E_EDIFACT
	0, 1, 1, 1, 1, 0,	// From E_BINARY
};

/*
 * Creates a encoding list (malloc)
 * returns encoding string
 * if lenp not null, target len stored
 * if error, null returned
 * if exact specified, then assumes shortcuts applicable for exact fit 
 * in target
 * 1. No unlatch to return to ASCII for last encoded byte after C40 or 
 * Text or X12
 * 2. No unlatch to return to ASCII for last 1 or 2 encoded bytes after 
 * EDIFACT
 * 3. Final C40 or text encoding exactly in last 2 bytes can have a shift 
 * 0 to pad to make a tripple
 * Only use the encoding from an exact request if the len matches the target, 
 * otherwise free the result and try again with exact=0
 */

static char *encmake(int l, unsigned char *s, int *lenp, char exact)
{
	char *encoding = 0;
	int p = l;
	char e;
	struct {
		// number of bytes of source that can be encoded in a row at this point
		// using this encoding mode
		short s;
		// number of bytes of target generated encoding from this point to end if
		// already in this encoding mode
		short t;
	} enc[MAXBARCODE][E_MAX];
	memset(&enc, 0, sizeof(enc));
	if (!l)
		return "";	// no length
	if (l > MAXBARCODE)
		return 0;	// not valid
	while (p--) {
		char b = 0, sub;
		int sl, tl, bl, t;
		// consider each encoding from this point
		// ASCII
		sl = tl = 1;
		if (isdigit(s[p]) && p + 1 < l && isdigit(s[p + 1]))
			sl = 2;	// double digit
		else if (s[p] & 0x80)
			tl = 2;	// high shifted
		bl = 0;
		if (p + sl < l)
			for (e = 0; e < E_MAX; e++)
				if (enc[p + sl][e].t && ((t = enc[p + sl][e].t +
							  switchcost[E_ASCII]
							  [e]) < bl || !bl)) {
					bl = t;
					b = e;
				}
		enc[p][E_ASCII].t = tl + bl;
		enc[p][E_ASCII].s = sl;
		if (bl && b == E_ASCII)
			enc[p][b].s += enc[p + sl][b].s;
		// C40
		sub = tl = sl = 0;
		do {
			unsigned char c = s[p + sl++];
			if (c & 0x80) {	// shift + upper
				sub += 2;
				c &= 0x7F;
			}
			if (c != ' ' && !isdigit(c) && !isupper(c))
				sub++;	// shift
			sub++;
			while (sub >= 3) {
				sub -= 3;
				tl += 2;
			}
		} while (sub && p + sl < l);
		if (exact && sub == 2 && p + sl == l) {
			// special case, can encode last block with shift 0 at end (Is this 
			// valid when not end of target buffer?)
			sub = 0;
			tl += 2;
		}
		if (!sub) {	// can encode C40
			bl = 0;
			if (p + sl < l)
				for (e = 0; e < E_MAX; e++)
					if (enc[p + sl][e].t
					    &&
					    ((t =
					      enc[p + sl][e].t +
					      switchcost[E_C40][e]) < bl
					     || !bl)) {
						bl = t;
						b = e;
					}
			if (exact && enc[p + sl][E_ASCII].t == 1 && 1 < bl) {
				// special case, switch to ASCII for last bytes
				bl = 1;
				b = E_ASCII;
			}
			enc[p][E_C40].t = tl + bl;
			enc[p][E_C40].s = sl;
			if (bl && b == E_C40)
				enc[p][b].s += enc[p + sl][b].s;
		}
		// Text
		sub = tl = sl = 0;
		do {
			unsigned char c = s[p + sl++];
			if (c & 0x80) {	// shift + upper
				sub += 2;
				c &= 0x7F;
			}
			if (c != ' ' && !isdigit(c) && !islower(c))
				sub++;	// shift
			sub++;
			while (sub >= 3) {
				sub -= 3;
				tl += 2;
			}
		} while (sub && p + sl < l);
		if (exact && sub == 2 && p + sl == l) {
			// special case, can encode last block with shift 0 at end (Is this 
			// valid when not end of target buffer?)
			sub = 0;
			tl += 2;
		}
		if (!sub && sl) {	// can encode Text
			bl = 0;
			if (p + sl < l)
				for (e = 0; e < E_MAX; e++)
					if (enc[p + sl][e].t
					    &&
					    ((t =
					      enc[p + sl][e].t +
					      switchcost[E_TEXT][e]) < bl
					     || !bl)) {
						bl = t;
						b = e;
					}
			if (exact && enc[p + sl][E_ASCII].t == 1 && 1 < bl) {	// special case, switch to ASCII for last bytes
				bl = 1;
				b = E_ASCII;
			}
			enc[p][E_TEXT].t = tl + bl;
			enc[p][E_TEXT].s = sl;
			if (bl && b == E_TEXT)
				enc[p][b].s += enc[p + sl][b].s;
		}
		// X12
		sub = tl = sl = 0;
		do {
			unsigned char c = s[p + sl++];
			if (c != 13 && c != '*' && c != '>' && c != ' '
			    && !isdigit(c) && !isupper(c)) {
				sl = 0;
				break;
			}
			sub++;
			while (sub >= 3) {
				sub -= 3;
				tl += 2;
			}
		} while (sub && p + sl < l);
		if (!sub && sl) {	// can encode X12
			bl = 0;
			if (p + sl < l)
				for (e = 0; e < E_MAX; e++)
					if (enc[p + sl][e].t
					    &&
					    ((t =
					      enc[p + sl][e].t +
					      switchcost[E_X12][e]) < bl
					     || !bl)) {
						bl = t;
						b = e;
					}
			if (exact && enc[p + sl][E_ASCII].t == 1 && 1 < bl) {
				// special case, switch to ASCII for last bytes
				bl = 1;
				b = E_ASCII;
			}
			enc[p][E_X12].t = tl + bl;
			enc[p][E_X12].s = sl;
			if (bl && b == E_X12)
				enc[p][b].s += enc[p + sl][b].s;
		}
		// EDIFACT
		sl = bl = 0;
		if (s[p + 0] >= 32 && s[p + 0] <= 94) {	// can encode 1
			char bs = 0;
			if (p + 1 == l && (!bl || bl < 2)) {
				bl = 2;
				bs = 1;
			} else
				for (e = 0; e < E_MAX; e++)
					if (e != E_EDIFACT && enc[p + 1][e].t
					    &&
					    ((t =
					      2 + enc[p + 1][e].t +
					      switchcost[E_ASCII][e])
					     < bl || !bl))	// E_ASCII as allowed for unlatch
					{
						bs = 1;
						bl = t;
						b = e;
					}
			if (p + 1 < l && s[p + 1] >= 32 && s[p + 1] <= 94) {	// can encode 2
				if (p + 2 == l && (!bl || bl < 2)) {
					bl = 3;
					bs = 2;
				} else
					for (e = 0; e < E_MAX; e++)
						if (e != E_EDIFACT
						    && enc[p + 2][e].t
						    &&
						    ((t =
						      3 + enc[p + 2][e].t +
						      switchcost[E_ASCII][e])
						     < bl || !bl))	// E_ASCII as allowed for unlatch
						{
							bs = 2;
							bl = t;
							b = e;
						}
				if (p + 2 < l && s[p + 2] >= 32 && s[p + 2] <= 94) {	// can encode 3
					if (p + 3 == l && (!bl || bl < 3)) {
						bl = 3;
						bs = 3;
					} else
						for (e = 0; e < E_MAX; e++)
							if (e != E_EDIFACT
							    && enc[p + 3][e].t
							    &&
							    ((t =
							      3 + enc[p +
								      3][e].t +
							      switchcost
							      [E_ASCII][e])
							     < bl || !bl))	// E_ASCII as allowed for unlatch
							{
								bs = 3;
								bl = t;
								b = e;
							}
					if (p + 4 < l && s[p + 3] >= 32 && s[p + 3] <= 94) {	// can encode 4
						if (p + 4 == l
						    && (!bl || bl < 3)) {
							bl = 3;
							bs = 4;
						} else {
							for (e = 0; e < E_MAX;
							     e++)
								if (enc[p + 4]
								    [e].t
								    &&
								    ((t =
								      3 +
								      enc[p +
									  4][e].
								      t +
								      switchcost
								      [E_EDIFACT]
								      [e]) < bl
								     || !bl)) {
									bs = 4;
									bl = t;
									b = e;
								}
							if (exact
							    && enc[p +
								   4][E_ASCII].t
							    && enc[p +
								   4][E_ASCII].
							    t <= 2
							    && (t =
								3 + enc[p +
									4]
								[E_ASCII].t) <
							    bl) {
								// special case, switch to ASCII for last 1 ot two bytes
								bs = 4;
								bl = t;
								b = E_ASCII;
							}
						}
					}
				}
			}
			enc[p][E_EDIFACT].t = bl;
			enc[p][E_EDIFACT].s = bs;
			if (bl && b == E_EDIFACT)
				enc[p][b].s += enc[p + bs][b].s;
		}
		// Binary
		bl = 0;
		for (e = 0; e < E_MAX; e++)
			if (enc[p + 1][e].t
			    &&
			    ((t =
			      enc[p + 1][e].t + switchcost[E_BINARY][e] +
			      ((e == E_BINARY
				&& enc[p + 1][e].t == 249) ? 1 : 0))
			     < bl || !bl)) {
				bl = t;
				b = e;
			}
		enc[p][E_BINARY].t = 1 + bl;
		enc[p][E_BINARY].s = 1;
		if (bl && b == E_BINARY)
			enc[p][b].s += enc[p + 1][b].s;
		/*
		 * fprintf (stderr, "%d:", p); for (e = 0; e < E_MAX; e++) fprintf \
		 * (stderr, " %c*%d/%d", encchr[e], enc[p][e].s, enc[p][e].t); \
		 * fprintf (stderr, "\n");
		 */
	}
	encoding = safemalloc(l + 1);
	p = 0;
	{
		char cur = E_ASCII;	// starts ASCII
		while (p < l) {
			int t, m = 0;
			char b = 0;
			for (e = 0; e < E_MAX; e++)
				if (enc[p][e].t
				    && ((t = enc[p][e].t + switchcost[cur][e]) <
					m || t == m && e == cur || !m)) {
					b = e;
					m = t;
				}
			cur = b;
			m = enc[p][b].s;
			if (!p && lenp)
				*lenp = enc[p][b].t;
			while (p < l && m--)
				encoding[p++] = encchr[b];
		}
	}
	encoding[p] = 0;
	return encoding;
}

/*
 * Main encoding function
 * Returns the grid (malloced) containing the matrix. L corner at 0,0.
 * Takes suggested size in *Wptr, *Hptr, or 0,0. Fills in actual size.
 * Takes barcodelen and barcode to be encoded
 * Note, if *encodingptr is null, then fills with auto picked (malloced) 
 * encoding
 * If lenp not null, then the length of encoded data before any final 
 * unlatch or pad is stored
 * If maxp not null, then the max storage of this size code is stored
 * If eccp not null, then the number of ecc bytes used in this size is 
 * stored
 * Returns 0 on error (writes to stderr with details).
 */

unsigned char *iec16022ecc200(int *Wptr, int *Hptr, char **encodingptr,
			      int barcodelen, unsigned char *barcode,
			      int *lenp, int *maxp, int *eccp)
{
	unsigned char binary[3000];	// encoded raw data and ecc to place in barcode
	int W = 0, H = 0;
	char *encoding = 0;
	unsigned char *grid = 0;
	struct ecc200matrix_s *matrix;
	memset(binary, 0, sizeof(binary));
	if (encodingptr)
		encoding = *encodingptr;
	if (Wptr)
		W = *Wptr;
	if (Hptr)
		H = *Hptr;

	// encoding
	if (W) {		// known size
		for (matrix = ecc200matrix; matrix->W && (matrix->W != W ||
							  matrix->H != H);
		     matrix++) ;
		if (!matrix->W) {
			fprintf(stderr, "Invalid size %dx%d\n", W, H);
			return 0;
		}
		if (!encoding) {
			int len;
			char *e = encmake(barcodelen, barcode, &len, 1);
			if (e && len != matrix->bytes) {	// try not an exact fit
				free(e);
				e = encmake(barcodelen, barcode, &len, 0);
				if (len > matrix->bytes) {
					fprintf(stderr,
						"Cannot make barcode fit %dx%d\n",
						W, H);
					return 0;
				}
			}
			encoding = e;
		}
	} else {
		// find a suitable encoding
		if (encoding == NULL)
			encoding = encmake(barcodelen, barcode, NULL, 1);

		if (encoding) {	// find one that fits chosen encoding
			for (matrix = ecc200matrix; matrix->W; matrix++)
				if (ecc200encode
				    (binary, matrix->bytes, barcode, barcodelen,
				     encoding, 0))
					break;
		} else {
			int len;
			char *e;
			e = encmake(barcodelen, barcode, &len, 1);
			for (matrix = ecc200matrix;
			     matrix->W && matrix->bytes != len; matrix++) ;
			if (e && !matrix->W) {	// try for non exact fit
				free(e);
				e = encmake(barcodelen, barcode, &len, 0);
				for (matrix = ecc200matrix;
				     matrix->W && matrix->bytes < len;
				     matrix++) ;
			}
			encoding = e;
		}
		if (!matrix->W) {
			fprintf(stderr,
				"Cannot find suitable size, barcode too long\n");
			return 0;
		}
		W = matrix->W;
		H = matrix->H;
	}
	if (!ecc200encode(binary, matrix->bytes, barcode, barcodelen,
			  encoding, lenp)) {
		fprintf(stderr, "Barcode too long for %dx%d\n", W, H);
		return 0;
	}
	// ecc code
	ecc200(binary, matrix->bytes, matrix->datablock, matrix->rsblock);
	{			// placement
		int x, y, NC, NR, *places;
		NC = W - 2 * (W / matrix->FW);
		NR = H - 2 * (H / matrix->FH);
		places = safemalloc(NC * NR * sizeof(int));
		ecc200placement(places, NR, NC);
		grid = safemalloc(W * H);
		memset(grid, 0, W * H);
		for (y = 0; y < H; y += matrix->FH) {
			for (x = 0; x < W; x++)
				grid[y * W + x] = 1;
			for (x = 0; x < W; x += 2)
				grid[(y + matrix->FH - 1) * W + x] = 1;
		}
		for (x = 0; x < W; x += matrix->FW) {
			for (y = 0; y < H; y++)
				grid[y * W + x] = 1;
			for (y = 0; y < H; y += 2)
				grid[y * W + x + matrix->FW - 1] = 1;
		}
		for (y = 0; y < NR; y++) {
			for (x = 0; x < NC; x++) {
				int v = places[(NR - y - 1) * NC + x];
				//fprintf (stderr, "%4d", v);
				if (v == 1 || v > 7
				    && (binary[(v >> 3) - 1] & (1 << (v & 7))))
					grid[(1 + y +
					      2 * (y / (matrix->FH - 2))) * W +
					     1 + x +
					     2 * (x / (matrix->FW - 2))] = 1;
			}
			//fprintf (stderr, "\n");
		}
		free(places);
	}
	if (Wptr)
		*Wptr = W;
	if (Hptr)
		*Hptr = H;
	if (encodingptr)
		*encodingptr = encoding;
	if (maxp)
		*maxp = matrix->bytes;
	if (eccp)
		*eccp =
		    (matrix->bytes + 2) / matrix->datablock * matrix->rsblock;
	return grid;
}