zint/backend/dm200.c

/* dm200.c Handles Data Matrix ECC 200 symbols */

/*
    libzint - the open source barcode library
    Copyright (C) 2009 Robin Stuart <robin@zint.org.uk>
    
    developed from and including some functions from:
	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 3 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#ifdef _MSC_VER
#include <malloc.h> 
#endif
#include "reedsol.h"
#include "common.h"
#include "dm200.h"

 // 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--];
	}
	rs_free();
}

int isx12(unsigned char source)
{
	if(source == 13) { return 1; }
	if(source == 42) { return 1; }
	if(source == 62) { return 1; }
	if(source == 32) { return 1; }
	if((source >= '0') && (source <= '9')) { return 1; }
	if((source >= 'A') && (source <= 'Z')) { return 1; }
	
	return 0;
}

void dminsert(char binary_string[], int posn, char newbit)
{ /* Insert a character into the middle of a string at position posn */
	int i, end;
	
	end = strlen(binary_string);
	for(i = end; i > posn; i--) {
		binary_string[i] = binary_string[i - 1];
	}
	binary_string[posn] = newbit;
}

void insert_value(unsigned char binary_stream[], int posn, int streamlen, char newbit)
{
	int i;
	
	for(i = streamlen; i > posn; i--) {
		binary_stream[i] = binary_stream[i - 1];
	}
	binary_stream[posn] = newbit;
}

int look_ahead_test(unsigned char source[], int sourcelen, int position, int current_mode, int gs1)
{
	/* A custom version of the 'look ahead test' from Annex P */
	/* This version is deliberately very reluctant to end a data stream with EDIFACT encoding */
	
	float ascii_count, c40_count, text_count, x12_count, edf_count, b256_count, best_count;
	int sp, done, best_scheme;
	char reduced_char;
	
	/* step (j) */
	if(current_mode == DM_ASCII) {
		ascii_count = 0.0;
		c40_count = 1.0;
		text_count = 1.0;
		x12_count = 1.0;
		edf_count = 1.0;
		b256_count = 1.25;
	} else {
		ascii_count = 1.0;
		c40_count = 2.0;
		text_count = 2.0;
		x12_count = 2.0;
		edf_count = 2.0;
		b256_count = 2.25;
	}
	
	switch(current_mode) {
		case DM_C40: c40_count = 0.0; break;
		case DM_TEXT: text_count = 0.0; break;
		case DM_X12: x12_count = 0.0; break;
		case DM_EDIFACT: edf_count = 0.0; break;
		case DM_BASE256: b256_count = 0.0; break;
	}
	
	for(sp = position; (sp < sourcelen) && (sp <= (position + 8)); sp++) {
		
		if(source[sp] <= 127) { reduced_char = source[sp]; } else { reduced_char = source[sp] - 127; }
		
		if((source[sp] >= '0') && (source[sp] <= '9')) { ascii_count += 0.5; } else { ascii_count += 1.0; }
		if(source[sp] > 127) { ascii_count += 1.0; }
		
		done = 0;
		if(reduced_char == ' ') { c40_count += (2.0 / 3.0); done = 1; }
		if((reduced_char >= '0') && (reduced_char <= '9')) { c40_count += (2.0 / 3.0); done = 1; }
		if((reduced_char >= 'A') && (reduced_char <= 'Z')) { c40_count += (2.0 / 3.0); done = 1; }
		if(source[sp] > 127) { c40_count += (4.0 / 3.0); }
		if(done == 0) { c40_count += (4.0 / 3.0); }
		
		done = 0;
		if(reduced_char == ' ') { text_count += (2.0 / 3.0); done = 1; }
		if((reduced_char >= '0') && (reduced_char <= '9')) { text_count += (2.0 / 3.0); done = 1; }
		if((reduced_char >= 'a') && (reduced_char <= 'z')) { text_count += (2.0 / 3.0); done = 1; }
		if(source[sp] > 127) { text_count += (4.0 / 3.0); }
		if(done == 0) { text_count += (4.0 / 3.0); }
		
		if(isx12(source[sp])) { x12_count += (2.0 / 3.0); } else { x12_count += 4.0; }
		
		/* step (p) */
		done = 0;
		if((source[sp] >= ' ') && (source[sp] <= '^')) { edf_count += (3.0 / 4.0); } else { edf_count += 4.0; }
		if(gs1 && (source[sp] == '[')) { edf_count += 4.0; }
		if(sp >= (sourcelen - 5)) { edf_count += 4.0; } /* MMmmm fudge! */
		
		/* step (q) */
		if(gs1 && (source[sp] == '[')) { b256_count += 4.0; } else { b256_count += 1.0; }
		
		/*printf("lat a%.2f c%.2f t%.2f x%.2f e%.2f b%.2f\n", ascii_count, c40_count, text_count, x12_count, edf_count, b256_count);*/
		
	}
	
	best_count = ascii_count;
	best_scheme = DM_ASCII;
	
	if(b256_count <= best_count) {
		best_count = b256_count;
		best_scheme = DM_BASE256;
	}
	
	if(edf_count <= best_count) {
		best_count = edf_count;
		best_scheme = DM_EDIFACT;
	}
	
	if(text_count <= best_count) {
		best_count = text_count;
		best_scheme = DM_TEXT;
	}
	
	if(x12_count <= best_count) {
		best_count = x12_count;
		best_scheme = DM_X12;
	}
	
	if(c40_count <= best_count) {
		best_count = c40_count;
		best_scheme = DM_C40;
	}
	
	return best_scheme;
}

int dm200encode(struct zint_symbol *symbol, unsigned char source[], unsigned char target[], int *last_mode)
{
	/* Encodes data using ASCII, C40, Text, X12, EDIFACT or Base 256 modes as appropriate */
	/* Supports encoding FNC1 in supporting systems */
	
	int sp, tp, i, gs1;
	int current_mode, next_mode;
	int inputlen = ustrlen(source);
	int c40_buffer[6], c40_p;
	int text_buffer[6], text_p;
	int x12_buffer[6], x12_p;
	int edifact_buffer[8], edifact_p;
#ifndef _MSC_VER
        char binary[2 * inputlen];
#else
        char* binary = (char*)_alloca(2 * inputlen);
#endif
	sp = 0;
	tp = 0;
	memset(c40_buffer, 0, 6);
	c40_p = 0;
	memset(text_buffer, 0, 6);
	text_p = 0;
	memset(x12_buffer, 0, 6);
	x12_p = 0;
	memset(edifact_buffer, 0, 8);
	edifact_p = 0;
	strcpy(binary, "");
	
	if(symbol->nullchar != 0x00) {
		for(i = 0; i < inputlen; i++) {
			if(source[i] == symbol->nullchar) {
				source[i] = 0x00;
			}
		}
	}
	
	/* step (a) */
	current_mode = DM_ASCII;
	next_mode = DM_ASCII;
	
	if(symbol->input_mode == GS1_MODE) { gs1 = 1; } else { gs1 = 0; }
	
	if(gs1) { target[tp] = 232; tp++; concat(binary, " "); } /* FNC1 */
	
	while (sp < inputlen) {
		
		current_mode = next_mode;
		
		/* step (b) - ASCII encodation */
		if(current_mode == DM_ASCII) {
			next_mode = DM_ASCII;
			
			if(istwodigits(source, sp) && ((sp + 1) != inputlen)) {
				target[tp] = (10 * ctoi(source[sp])) + ctoi(source[sp + 1]) + 130;
				tp++; concat(binary, " ");
				sp += 2;
			} else {
				next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
				
				if(next_mode != DM_ASCII) {
					switch(next_mode) {
						case DM_C40: target[tp] = 230; tp++; concat(binary, " "); break;
						case DM_TEXT: target[tp] = 239; tp++; concat(binary, " "); break;
						case DM_X12: target[tp] = 238; tp++; concat(binary, " "); break;
						case DM_EDIFACT: target[tp] = 240; tp++; concat(binary, " "); break;
						case DM_BASE256: target[tp] = 231; tp++; concat(binary, " "); break;
					}
				} else {
					if(source[sp] > 127) {
						target[tp] = 235; /* FNC4 */
						tp++;
						target[tp] = (source[sp] - 128) + 1;
						tp++; concat(binary, "  ");
					} else {
						if(gs1 && (source[sp] == '[')) {
							target[tp] = 232; /* FNC1 */
						} else {
							target[tp] = source[sp] + 1;
						}
						tp++; 
						concat(binary, " ");
					}
					sp++;
				}
			}
			
		}
		
		/* step (c) C40 encodation */
		if(current_mode == DM_C40) {
			int shift_set, value;
			
			next_mode = DM_C40;
			if(c40_p == 0) {
				next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
			}
			
			if(next_mode != DM_C40) {
				target[tp] = 254; tp++; concat(binary, " ");/* Unlatch */
			} else {
				if(source[sp] > 127) {
					c40_buffer[c40_p] = 1; c40_p++;
					c40_buffer[c40_p] = 30; c40_p++; /* Upper Shift */
					shift_set = c40_shift[source[sp] - 128];
					value = c40_value[source[sp] - 128];
				} else {
					shift_set = c40_shift[source[sp]];
					value = c40_value[source[sp]];
				}
				
				if(gs1 && (source[sp] == '[')) {
					shift_set = 2;
					value = 27; /* FNC1 */
				}
				
				if(shift_set != 0) {
					c40_buffer[c40_p] = shift_set - 1; c40_p++;
				}
				c40_buffer[c40_p] = value; c40_p++;
				
				if(c40_p >= 3) {
					int iv;
					
					iv = (1600 * c40_buffer[0]) + (40 * c40_buffer[1]) + (c40_buffer[2]) + 1;
					target[tp] = iv / 256; tp++;
					target[tp] = iv % 256; tp++;
					concat(binary, "  ");
					
					c40_buffer[0] = c40_buffer[3];
					c40_buffer[1] = c40_buffer[4];
					c40_buffer[2] = c40_buffer[5];
					c40_buffer[3] = 0;
					c40_buffer[4] = 0;
					c40_buffer[5] = 0;
					c40_p -= 3;
				}
				sp++;
			}
		}
		
		/* step (d) Text encodation */
		if(current_mode == DM_TEXT) {
			int shift_set, value;
			
			next_mode = DM_TEXT;
			if(text_p == 0) {
				next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
			}
			
			if(next_mode != DM_TEXT) {
				target[tp] = 254; tp++; concat(binary, " ");/* Unlatch */
			} else {
				if(source[sp] > 127) {
					text_buffer[text_p] = 1; text_p++;
					text_buffer[text_p] = 30; text_p++; /* Upper Shift */
					shift_set = text_shift[source[sp] - 128];
					value = text_value[source[sp] - 128];
				} else {
					shift_set = text_shift[source[sp]];
					value = text_value[source[sp]];
				}
				
				if(gs1 && (source[sp] == '[')) {
					shift_set = 2;
					value = 27; /* FNC1 */
				}
				
				if(shift_set != 0) {
					text_buffer[text_p] = shift_set - 1; text_p++;
				}
				text_buffer[text_p] = value; text_p++;
				
				if(text_p >= 3) {
					int iv;
					
					iv = (1600 * text_buffer[0]) + (40 * text_buffer[1]) + (text_buffer[2]) + 1;
					target[tp] = iv / 256; tp++;
					target[tp] = iv % 256; tp++;
					concat(binary, "  ");
					
					text_buffer[0] = text_buffer[3];
					text_buffer[1] = text_buffer[4];
					text_buffer[2] = text_buffer[5];
					text_buffer[3] = 0;
					text_buffer[4] = 0;
					text_buffer[5] = 0;
					text_p -= 3;
				}
				sp++;
			}
		}
		
		/* step (e) X12 encodation */
		if(current_mode == DM_X12) {
			int value = 0;
			
			next_mode = DM_X12;
			if(text_p == 0) {
				next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
			}
			
			if(next_mode != DM_X12) {
				target[tp] = 254; tp++; concat(binary, " ");/* Unlatch */
			} else {
				if(source[sp] == 13) { value = 0; }
				if(source[sp] == '*') { value = 1; }
				if(source[sp] == '>') { value = 2; }
				if(source[sp] == ' ') { value = 3; }
				if((source[sp] >= '0') && (source[sp] <= '9')) { value = (source[sp] - '0') + 4; }
				if((source[sp] >= 'A') && (source[sp] <= 'Z')) { value = (source[sp] - 'A') + 14; }
				
				x12_buffer[x12_p] = value; x12_p++;
				
				if(x12_p >= 3) {
					int iv;
					
					iv = (1600 * x12_buffer[0]) + (40 * x12_buffer[1]) + (x12_buffer[2]) + 1;
					target[tp] = iv / 256; tp++;
					target[tp] = iv % 256; tp++;
					concat(binary, "  ");
					
					x12_buffer[0] = x12_buffer[3];
					x12_buffer[1] = x12_buffer[4];
					x12_buffer[2] = x12_buffer[5];
					x12_buffer[3] = 0;
					x12_buffer[4] = 0;
					x12_buffer[5] = 0;
					x12_p -= 3;
				}
				sp++;
			}
		}
		
		/* step (f) EDIFACT encodation */
		if(current_mode == DM_EDIFACT) {
			int value = 0;
			
			next_mode = DM_EDIFACT;
			if(edifact_p == 3) {
				next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
			}
			
			if(next_mode != DM_EDIFACT) {
				edifact_buffer[edifact_p] = 31; edifact_p++;
			} else {
				if((source[sp] >= '@') && (source[sp] <= '^')) { value = source[sp] - '@'; }
				if((source[sp] >= ' ') && (source[sp] <= '?')) { value = source[sp]; }
				
				edifact_buffer[edifact_p] = value; edifact_p++;
				sp++;
			}
				
			if(edifact_p >= 4) {
				target[tp] = (edifact_buffer[0] << 2) + ((edifact_buffer[1] & 0x30) >> 4); tp++;
				target[tp] = ((edifact_buffer[1] & 0x0f) << 4) + ((edifact_buffer[2] & 0x3c) >> 2); tp++;
				target[tp] = ((edifact_buffer[2] & 0x03) << 6) + edifact_buffer[3]; tp++;
				concat(binary, "   ");
				
				edifact_buffer[0] = edifact_buffer[4];
				edifact_buffer[1] = edifact_buffer[5];
				edifact_buffer[2] = edifact_buffer[6];
				edifact_buffer[3] = edifact_buffer[7];
				edifact_buffer[4] = 0;
				edifact_buffer[5] = 0;
				edifact_buffer[6] = 0;
				edifact_buffer[7] = 0;
				edifact_p -= 4;
			}
		}
		
		/* step (g) Base 256 encodation */
		if(current_mode == DM_BASE256) {
			next_mode = look_ahead_test(source, inputlen, sp, current_mode, gs1);
			
			if(next_mode == DM_BASE256) {
				target[tp] = source[sp];
				tp++;
				sp++;
				concat(binary, "b");
			} else {
				next_mode = DM_ASCII;
			}
		}
		
		if(tp > 1558) {
			return 0;
		}
		
	} /* while */
	
	/* Empty buffers */
	if(c40_p == 2) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 2] + 1; tp++;
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "   ");
		current_mode = DM_ASCII;
	}
	if(c40_p == 1) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "  ");
		current_mode = DM_ASCII;
	}
	
	if(text_p == 2) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 2] + 1; tp++;
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "   ");
		current_mode = DM_ASCII;
	}
	if(text_p == 1) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "  ");
		current_mode = DM_ASCII;
	}
	
	if(x12_p == 2) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 2] + 1; tp++;
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "   ");
		current_mode = DM_ASCII;
	}
	if(x12_p == 1) {
		target[tp] = 254; tp++; /* unlatch */
		target[tp] = source[inputlen - 1] + 1; tp++;
		concat(binary, "  ");
		current_mode = DM_ASCII;
	}

	/* Add length and randomising algorithm to b256 */
	i = 0;
	while (i < tp) {
		if(binary[i] == 'b') {
			if((i == 0) || ((i != 0) && (binary[i - 1] != 'b'))) {
				/* start of binary data */
				int binary_count; /* length of b256 data */
				
				for(binary_count = 0; binary[binary_count + i] == 'b'; binary_count++);
				
				if(binary_count <= 249) {
					dminsert(binary, i, 'b');
					insert_value(target, i, tp, binary_count); tp++;
				} else {
					dminsert(binary, i, 'b');
					dminsert(binary, i + 1, 'b');
					insert_value(target, i, tp, (binary_count / 250) + 249); tp++;
					insert_value(target, i + 1, tp, binary_count % 250); tp++;
				}
			}
		}
		i++;
	}
	
	for(i = 0; i < tp; i++) {
		if(binary[i] == 'b') {
			int prn, temp;
			
			prn = ((149 * (i + 1)) % 255) + 1;
			temp = target[i] + prn;
			if (temp <= 255) { target[i] = temp; } else { target[i] = temp - 256; }
		}
	}
	
	/*
	for(i = 0; i < tp; i++){
		printf("%02X ", target[i]);
	}
	printf("\n");
	*/
	
	*(last_mode) = current_mode;
	return tp;
}

void add_tail(unsigned char target[], int tp, int tail_length, int last_mode)
{
	/* adds unlatch and pad bits */
	int i, prn, temp;
	
	switch(last_mode) {
		case DM_C40:
		case DM_TEXT:
		case DM_X12:
			target[tp] = 254; tp++; /* Unlatch */
			tail_length--;
	}
	
	for(i = tail_length; i > 0; i--) {
		if(i == tail_length) {
			target[tp] = 129; tp++; /* Pad */
		} else {
			prn = ((149 * (tp + 1)) % 253) + 1;
			temp = 129 + prn;
			if(temp <= 254) {
				target[tp] = temp; tp++;
			} else {
				target[tp] = temp - 254; tp++;
			}
		}
	}
}

int data_matrix_200(struct zint_symbol *symbol, unsigned char source[])
{
	int inputlen, i;
	inputlen = ustrlen(source);
	unsigned char binary[2000];
	int binlen;
	int symbolsize, optionsize, calcsize;
	int taillength, error_number = 0;
	int H, W, FH, FW, datablock, bytes, rsblock;
	int last_mode;
	unsigned char *grid = 0;
	
	binlen = dm200encode(symbol, source, binary, &last_mode);
	if(binlen == 0) {
		strcpy(symbol->errtxt, "Data too long to fit in symbol");
		return ERROR_TOO_LONG;
	}
	
	if((symbol->option_2 >= 1) && (symbol->option_2 <= 30)) {
		optionsize = intsymbol[symbol->option_2 - 1];
	} else {
		optionsize = -1;
	}
	
	calcsize = 0;
	for(i = 0; i < 30; i++) {
		if(matrixbytes[i] < binlen) {
			calcsize = i;
		}
	}
	calcsize++;
	
	if(calcsize <= optionsize) {
		symbolsize = optionsize;
	} else {
		symbolsize = calcsize;
		if(optionsize != -1) {
			/* flag an error */
			error_number = WARN_INVALID_OPTION;
			strcpy(symbol->errtxt, "Data does not fit in selected symbol size");
		}
	}
	
	H = matrixH[symbolsize];
	W = matrixW[symbolsize];
	FH = matrixFH[symbolsize];
	FW = matrixFW[symbolsize];
	bytes = matrixbytes[symbolsize];
	datablock = matrixdatablock[symbolsize];
	rsblock = matrixrsblock[symbolsize];
	
	taillength = bytes - binlen;
	
	if(taillength != 0) {
		add_tail(binary, binlen, taillength, last_mode);
	}
	
	// ecc code
	ecc200(binary, bytes, datablock, rsblock);
	{			// placement
		int x, y, NC, NR, *places;
		NC = W - 2 * (W / FW);
		NR = H - 2 * (H / FH);
		places = (int*)safemalloc(NC * NR * sizeof(int));
		ecc200placement(places, NR, NC);
		grid = (unsigned char*)safemalloc(W * H);
		memset(grid, 0, W * H);
		for (y = 0; y < H; y += FH) {
			for (x = 0; x < W; x++)
				grid[y * W + x] = 1;
			for (x = 0; x < W; x += 2)
				grid[(y + FH - 1) * W + x] = 1;
		}
		for (x = 0; x < W; x += FW) {
			for (y = 0; y < H; y++)
				grid[y * W + x] = 1;
			for (y = 0; y < H; y += 2)
				grid[y * W + x + 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 / (FH - 2))) * W + 1 + x + 2 * (x / (FW - 2))] = 1;
			}
			//fprintf (stderr, "\n");
		}
		for(y = H - 1; y >= 0; y--) {
			int x;
			for(x = 0; x < W; x++) {
				if(grid[W * y + x]) {
					set_module(symbol, (H - y) - 1, x);
				}
			}
			symbol->row_height[(H - y) - 1] = 1;
		}
		free(grid);
		free(places);
	}
	
	symbol->rows = H;
	symbol->width = W;
	
	return error_number;
}