GS1 Syntax Dictionary: Linter reference
A reference to the AI component linter routines referred to by the GS1 Syntax Dictionary. Copyright (c) 2022-2024 GS1 AISBL.
lint_yyyymmd0.c File Reference

Purpose

The yyyymmd0 linter ensures that the data represents a meaningful date, in YYYYMMDD format, additionally permitting YYYYMM00 format indicating an unspecified day.

Functional Description

◆ gs1_lint_yyyymmd0()

GS1_SYNTAX_DICTIONARY_API gs1_lint_err_t gs1_lint_yyyymmd0 ( const char *const  data,
size_t *const  err_pos,
size_t *const  err_len 
)

Used to ensure that an AI component conforms to the YYYYMMDD or YYYYMM00 formats.

Parameters
[in]dataPointer to the null-terminated data to be linted. Must not be NULL.
[out]err_posTo facilitate error highlighting, the start position of the bad data is written to this pointer, if not NULL.
[out]err_lenThe length of the bad data is written to this pointer, if not NULL.
Returns
GS1_LINTER_OK if okay.
GS1_LINTER_DATE_TOO_SHORT if the data is too short for YYYYMMDD format.
GS1_LINTER_DATE_TOO_LONG if the data is too long for YYYYMMDD format.
GS1_LINTER_NON_DIGIT_CHARACTER if the data contains a non-digit character.
GS1_LINTER_ILLEGAL_MONTH if the data contains an invalid month.
GS1_LINTER_ILLEGAL_DAY if the data contains an invalid day of the month.
55{
56
57/// \cond
58#define XX(d) ( (data[d] - '0') * 10 + (data[d+1] - '0') )
59#define YY ( XX(0) * 100 + XX(2) )
60#define MM XX(4)
61#define DD XX(6)
62/// \endcond
63
64 static const unsigned char daysinmonth[] =
65 { 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
66
67 size_t len, pos;
68 unsigned char maxdd;
69
70 assert(data);
71
72 len = strlen(data);
73
74 /*
75 * Data must be eight characters.
76 *
77 */
78 if (len != 8) {
79 if (err_pos) *err_pos = 0;
80 if (err_len) *err_len = len;
82 }
83
84 /*
85 * Data must consist of all digits.
86 *
87 */
88 if ((pos = strspn(data, "0123456789")) != len) {
89 if (err_pos) *err_pos = pos;
90 if (err_len) *err_len = 1;
92 }
93
94 /*
95 * Validate that the month is 01 to 12.
96 *
97 */
98 if (MM < 1 || MM > 12) {
99 if (err_pos) *err_pos = 4;
100 if (err_len) *err_len = 2;
102 }
103
104 /*
105 * Validate the day, accounting for leap years
106 *
107 */
108 if (MM == 2) { /* February; account for leap years */
109 maxdd = ((YY % 4 == 0 && YY % 100 != 0) || YY % 400 == 0) ? 29 : 28;
110 } else {
111 maxdd = daysinmonth[MM - 1]; /* Based at 0 */
112 }
113
114 if (DD > maxdd) { /* Permit "00" */
115 if (err_pos) *err_pos = 6;
116 if (err_len) *err_len = 2;
118 }
119
120 return GS1_LINTER_OK;
121
122}
@ GS1_LINTER_ILLEGAL_DAY
The date contains an illegal day of the month.
Definition gs1syntaxdictionary.h:102
@ GS1_LINTER_DATE_TOO_LONG
The date is too long for YYMMDD format.
Definition gs1syntaxdictionary.h:95
@ GS1_LINTER_ILLEGAL_MONTH
The date contains an illegal month of the year.
Definition gs1syntaxdictionary.h:101
@ GS1_LINTER_DATE_TOO_SHORT
The date is too short for YYMMDD format.
Definition gs1syntaxdictionary.h:94
@ GS1_LINTER_OK
No issues were detected by the linter.
Definition gs1syntaxdictionary.h:66
@ GS1_LINTER_NON_DIGIT_CHARACTER
A non-digit character was found where a digit is expected.
Definition gs1syntaxdictionary.h:67