mirror of
https://github.com/zint/zint
synced 2024-11-16 20:57:25 +13:00
95 lines
3.0 KiB
C
95 lines
3.0 KiB
C
/* gs1.c - Verifies GS1 data */
|
|
|
|
/*
|
|
libzint - the open source barcode library
|
|
Copyright (C) 2009 Robin Stuart <robin@zint.org.uk>
|
|
|
|
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 <string.h>
|
|
#include <stdlib.h>
|
|
#include "common.h"
|
|
|
|
int gs1_verify(struct zint_symbol *symbol, unsigned char source[], char reduced[])
|
|
{
|
|
int i, j, last_ai, ai_latch;
|
|
char ai_string[4];
|
|
|
|
/* Detect extended ASCII characters */
|
|
for(i = 0; i < sourcelen; i++) {
|
|
if(source[i] >=128) {
|
|
strcpy(symbol->errtxt, "Extended ASCII characters are not supported by GS1");
|
|
return ERROR_INVALID_DATA;
|
|
}
|
|
}
|
|
|
|
/* Start with basic tests */
|
|
if(source[0] != '[') {
|
|
strcpy(symbol->errtxt, "Data does not start with an AI");
|
|
return ERROR_INVALID_DATA;
|
|
}
|
|
|
|
for(i = 0; i < ustrlen(source) - 1; i++) {
|
|
if((source[i] == '[') && (source[i + 1] == '[')) {
|
|
/* Can't have nested brackets - Quit */
|
|
strcpy(symbol->errtxt, "Nested AI detected (two or more open brackets)");
|
|
return ERROR_INVALID_DATA;
|
|
}
|
|
}
|
|
|
|
for(i = 0; i < ustrlen(source) - 1; i++) {
|
|
if((source[i] == ']') && (source[i + 1] == ']')) {
|
|
/* Can't have nested brackets - Quit */
|
|
strcpy(symbol->errtxt, "Nested AI detected (two or more close brackets)");
|
|
return ERROR_INVALID_DATA;
|
|
}
|
|
}
|
|
|
|
/* Resolve AI data - put resulting string in 'reduced' */
|
|
j = 0;
|
|
last_ai = 0;
|
|
ai_latch = 1;
|
|
for(i = 0; i < ustrlen(source); i++) {
|
|
if((source[i] != '[') && (source[i] != ']')) {
|
|
reduced[j] = source[i];
|
|
j++;
|
|
}
|
|
if(source[i] == '[') {
|
|
/* Start of an AI string */
|
|
if(ai_latch == 0) {
|
|
reduced[j] = '[';
|
|
j++;
|
|
}
|
|
ai_string[0] = source[i + 1];
|
|
ai_string[1] = source[i + 2];
|
|
ai_string[2] = '\0';
|
|
last_ai = atoi(ai_string);
|
|
ai_latch = 0;
|
|
/* The following values from GS1 specification figure 5.3.8.2.1 - 1
|
|
"Element Strings with Pre-Defined Length Using Application Identifiers" */
|
|
if((last_ai >= 0) && (last_ai <= 4)) { ai_latch = 1; }
|
|
if((last_ai >= 11) && (last_ai <= 20)) { ai_latch = 1; }
|
|
if(last_ai == 23) { ai_latch = 1; } /* legacy support - see 5.3.8.2.2 */
|
|
if((last_ai >= 31) && (last_ai <= 36)) { ai_latch = 1; }
|
|
if(last_ai == 41) { ai_latch = 1; }
|
|
}
|
|
/* The ']' character is simply dropped from the input */
|
|
}
|
|
reduced[j] = '\0';
|
|
|
|
/* the character '[' in the reduced string refers to the FNC1 character */
|
|
return 0;
|
|
} |