blob: 4044fc9e58b06c7dd775a95f333b4ae9dd565e99 [file] [log] [blame]
/*
* This comes from the musl C library which has been licensed under the permissive MIT license.
*
* Downloaded from https://git.musl-libc.org/cgit/musl/plain/src/time/strptime.c,
* commit 98e688a9da5e7b2925dda17a2d6820dddf1fb287.
*
* Lobotomized to remove references to nl_langinfo().
* Adjusted coding style to fit libyang's uncrustify rules.
* */
#include <ctype.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
char *
strptime(const char * restrict s, const char * restrict f, struct tm * restrict tm)
{
int i, w, neg, adj, min, range, *dest, dummy;
int want_century = 0, century = 0, relyear = 0;
while (*f) {
if (*f != '%') {
if (isspace(*f)) {
for ( ; *s && isspace(*s); s++) {}
} else if (*s != *f) {
return 0;
} else {
s++;
}
f++;
continue;
}
f++;
if (*f == '+') {
f++;
}
if (isdigit(*f)) {
char *new_f;
w = strtoul(f, &new_f, 10);
f = new_f;
} else {
w = -1;
}
adj = 0;
switch (*f++) {
case 'a':
case 'A':
case 'b':
case 'B':
case 'h':
case 'c':
goto fail_nl_langinfo;
case 'C':
dest = &century;
if (w < 0) {
w = 2;
}
want_century |= 2;
goto numeric_digits;
case 'd':
case 'e':
dest = &tm->tm_mday;
min = 1;
range = 31;
goto numeric_range;
case 'D':
s = strptime(s, "%m/%d/%y", tm);
if (!s) {
return 0;
}
break;
case 'H':
dest = &tm->tm_hour;
min = 0;
range = 24;
goto numeric_range;
case 'I':
dest = &tm->tm_hour;
min = 1;
range = 12;
goto numeric_range;
case 'j':
dest = &tm->tm_yday;
min = 1;
range = 366;
adj = 1;
goto numeric_range;
case 'm':
dest = &tm->tm_mon;
min = 1;
range = 12;
adj = 1;
goto numeric_range;
case 'M':
dest = &tm->tm_min;
min = 0;
range = 60;
goto numeric_range;
case 'n':
case 't':
for ( ; *s && isspace(*s); s++) {}
break;
case 'p':
case 'r':
goto fail_nl_langinfo;
case 'R':
s = strptime(s, "%H:%M", tm);
if (!s) {
return 0;
}
break;
case 'S':
dest = &tm->tm_sec;
min = 0;
range = 61;
goto numeric_range;
case 'T':
s = strptime(s, "%H:%M:%S", tm);
if (!s) {
return 0;
}
break;
case 'U':
case 'W':
/* Throw away result, for now. (FIXME?) */
dest = &dummy;
min = 0;
range = 54;
goto numeric_range;
case 'w':
dest = &tm->tm_wday;
min = 0;
range = 7;
goto numeric_range;
case 'x':
case 'X':
goto fail_nl_langinfo;
case 'y':
dest = &relyear;
w = 2;
want_century |= 1;
goto numeric_digits;
case 'Y':
dest = &tm->tm_year;
if (w < 0) {
w = 4;
}
adj = 1900;
want_century = 0;
goto numeric_digits;
case '%':
if (*s++ != '%') {
return 0;
}
break;
default:
return 0;
numeric_range:
if (!isdigit(*s)) {
return 0;
}
*dest = 0;
for (i = 1; i <= min + range && isdigit(*s); i *= 10) {
*dest = *dest * 10 + *s++ - '0';
}
if (*dest - min >= range) {
return 0;
}
*dest -= adj;
switch ((char *)dest - (char *)tm) {
case offsetof(struct tm, tm_yday):
;
}
goto update;
numeric_digits:
neg = 0;
if (*s == '+') {
s++;
} else if (*s == '-') {
neg = 1, s++;
}
if (!isdigit(*s)) {
return 0;
}
for (*dest = i = 0; i < w && isdigit(*s); i++) {
*dest = *dest * 10 + *s++ - '0';
}
if (neg) {
*dest = -*dest;
}
*dest -= adj;
goto update;
update:
// FIXME
;
}
}
if (want_century) {
tm->tm_year = relyear;
if (want_century & 2) {
tm->tm_year += century * 100 - 1900;
} else if (tm->tm_year <= 68) {
tm->tm_year += 100;
}
}
return (char *)s;
fail_nl_langinfo:
fprintf(stderr, "strptime: nl_langinfo not available");
return NULL;
}