in Sharing/Src/External/zint-2.4.3/src/backend/gs1.c [67:301]
int gs1_verify(struct zint_symbol *symbol, unsigned char source[], const unsigned int src_len, char reduced[])
{
int i, j, last_ai, ai_latch;
char ai_string[6];
int bracket_level, max_bracket_level, ai_length, max_ai_length, min_ai_length;
int ai_value[100], ai_location[100], ai_count, data_location[100], data_length[100];
int error_latch;
/* Detect extended ASCII characters */
for(i = 0; i < src_len; i++) {
if(source[i] >=128) {
strcpy(symbol->errtxt, "Extended ASCII characters are not supported by GS1");
return ZINT_ERROR_INVALID_DATA;
}
if(source[i] < 32) {
strcpy(symbol->errtxt, "Control characters are not supported by GS1");
return ZINT_ERROR_INVALID_DATA;
}
}
if(source[0] != '[') {
strcpy(symbol->errtxt, "Data does not start with an AI");
return ZINT_ERROR_INVALID_DATA;
}
/* Check the position of the brackets */
bracket_level = 0;
max_bracket_level = 0;
ai_length = 0;
max_ai_length = 0;
min_ai_length = 5;
j = 0;
ai_latch = 0;
for(i = 0; i < src_len; i++) {
ai_length += j;
if(((j == 1) && (source[i] != ']')) && ((source[i] < '0') || (source[i] > '9'))) { ai_latch = 1; }
if(source[i] == '[') { bracket_level++; j = 1; }
if(source[i] == ']') {
bracket_level--;
if(ai_length < min_ai_length) { min_ai_length = ai_length; }
j = 0;
ai_length = 0;
}
if(bracket_level > max_bracket_level) { max_bracket_level = bracket_level; }
if(ai_length > max_ai_length) { max_ai_length = ai_length; }
}
min_ai_length--;
if(bracket_level != 0) {
/* Not all brackets are closed */
strcpy(symbol->errtxt, "Malformed AI in input data (brackets don\'t match)");
return ZINT_ERROR_INVALID_DATA;
}
if(max_bracket_level > 1) {
/* Nested brackets */
strcpy(symbol->errtxt, "Found nested brackets in input data");
return ZINT_ERROR_INVALID_DATA;
}
if(max_ai_length > 4) {
/* AI is too long */
strcpy(symbol->errtxt, "Invalid AI in input data (AI too long)");
return ZINT_ERROR_INVALID_DATA;
}
if(min_ai_length <= 1) {
/* AI is too short */
strcpy(symbol->errtxt, "Invalid AI in input data (AI too short)");
return ZINT_ERROR_INVALID_DATA;
}
if(ai_latch == 1) {
/* Non-numeric data in AI */
strcpy(symbol->errtxt, "Invalid AI in input data (non-numeric characters in AI)");
return ZINT_ERROR_INVALID_DATA;
}
ai_count = 0;
for(i = 1; i < src_len; i++) {
if(source[i - 1] == '[') {
ai_location[ai_count] = i;
j = 0;
do {
ai_string[j] = source[i + j];
j++;
} while (ai_string[j - 1] != ']');
ai_string[j - 1] = '\0';
ai_value[ai_count] = atoi(ai_string);
ai_count++;
}
}
for(i = 0; i < ai_count; i++) {
data_location[i] = ai_location[i] + 3;
if(ai_value[i] >= 100) { data_location[i]++; }
if(ai_value[i] >= 1000) { data_location[i]++; }
data_length[i] = 0;
do {
data_length[i]++;
} while ((source[data_location[i] + data_length[i] - 1] != '[') && (source[data_location[i] + data_length[i] - 1] != '\0'));
data_length[i]--;
}
for(i = 0; i < ai_count; i++) {
if(data_length[i] == 0) {
/* No data for given AI */
strcpy(symbol->errtxt, "Empty data field in input data");
return ZINT_ERROR_INVALID_DATA;
}
}
error_latch = 0;
strcpy(ai_string, "");
for(i = 0; i < ai_count; i++) {
switch (ai_value[i]) {
case 0: if(data_length[i] != 18) { error_latch = 1; } break;
case 1:
case 2:
case 3: if(data_length[i] != 14) { error_latch = 1; } break;
case 4: if(data_length[i] != 16) { error_latch = 1; } break;
case 11:
case 12:
case 13:
case 14:
case 15:
case 16:
case 17:
case 18:
case 19: if(data_length[i] != 6) { error_latch = 1; } break;
case 20: if(data_length[i] != 2) { error_latch = 1; } break;
case 23:
case 24:
case 25:
case 39:
case 40:
case 41:
case 42:
case 70:
case 80:
case 81: error_latch = 2; break;
}
if(
((ai_value[i] >= 100) && (ai_value[i] <= 179))
|| ((ai_value[i] >= 1000) && (ai_value[i] <= 1799))
|| ((ai_value[i] >= 200) && (ai_value[i] <= 229))
|| ((ai_value[i] >= 2000) && (ai_value[i] <= 2299))
|| ((ai_value[i] >= 300) && (ai_value[i] <= 309))
|| ((ai_value[i] >= 3000) && (ai_value[i] <= 3099))
|| ((ai_value[i] >= 31) && (ai_value[i] <= 36))
|| ((ai_value[i] >= 310) && (ai_value[i] <= 369))
) {
error_latch = 2;
}
if((ai_value[i] >= 3100) && (ai_value[i] <= 3699)) {
if(data_length[i] != 6) {
error_latch = 1;
}
}
if(
((ai_value[i] >= 370) && (ai_value[i] <= 379))
|| ((ai_value[i] >= 3700) && (ai_value[i] <= 3799))
) {
error_latch = 2;
}
if((ai_value[i] >= 410) && (ai_value[i] <= 415)) {
if(data_length[i] != 13) {
error_latch = 1;
}
}
if(
((ai_value[i] >= 4100) && (ai_value[i] <= 4199))
|| ((ai_value[i] >= 700) && (ai_value[i] <= 703))
|| ((ai_value[i] >= 800) && (ai_value[i] <= 810))
|| ((ai_value[i] >= 900) && (ai_value[i] <= 999))
|| ((ai_value[i] >= 9000) && (ai_value[i] <= 9999))
) {
error_latch = 2;
}
if((error_latch < 4) && (error_latch > 0)) {
/* error has just been detected: capture AI */
itostr(ai_string, ai_value[i]);
error_latch += 4;
}
}
if(error_latch == 5) {
strcpy(symbol->errtxt, "Invalid data length for AI ");
concat(symbol->errtxt, ai_string);
return ZINT_ERROR_INVALID_DATA;
}
if(error_latch == 6) {
strcpy(symbol->errtxt, "Invalid AI value ");
concat(symbol->errtxt, ai_string);
return ZINT_ERROR_INVALID_DATA;
}
/* Resolve AI data - put resulting string in 'reduced' */
j = 0;
last_ai = 0;
ai_latch = 1;
for(i = 0; i < src_len; i++) {
if((source[i] != '[') && (source[i] != ']')) {
reduced[j++] = source[i];
}
if(source[i] == '[') {
/* Start of an AI string */
if(ai_latch == 0) {
reduced[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 "GS-1 General Specification version 8.0 issue 2, May 2008"
figure 5.4.8.2.1 - 1 "Element Strings with Pre-Defined Length Using Application Identifiers" */
if(
((last_ai >= 0) && (last_ai <= 4))
|| ((last_ai >= 11) && (last_ai <= 20))
|| (last_ai == 23) /* legacy support - see 5.3.8.2.2 */
|| ((last_ai >= 31) && (last_ai <= 36))
|| (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;
}