Files

73 lines
2.2 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sysdep.h>
#include <time.h>
static const char __wday_snames[7][4] = {
"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};
static const char __wday_lnames[7][11] = {
"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
};
static const char __mon_snames[12][4] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};
static const char __mon_lnames[12][11] = {
"January", "February", "March", "April", "May", "June", "July", "Auguest", "September", "October", "November", "December"
};
static inline size_t strftime_append(char* s, size_t remaining, const char* appendee)
{
size_t copy_size = min(remaining, strlen(appendee));
memcpy(s, appendee, copy_size);
return copy_size;
}
size_t strftime(char* s, size_t remaining, const char* format, const tm_t* tm)
{
char buf[32];
const char* p = format;
size_t written = 0;
remaining--;
while (*p) {
if (*p == '%' && *(p + 1)) {
p++;
size_t wr = 0;
switch (*p) {
case 'a':
wr = strftime_append((char*)(s + written), remaining, __wday_snames[tm->tm_wday]);
written += wr;
remaining -= wr;
break;
case 'A':
wr = strftime_append((char*)(s + written), remaining, __wday_lnames[tm->tm_wday]);
written += wr;
remaining -= wr;
break;
case 'R':
if (tm->tm_min < 10) {
snprintf(buf, 32, "%d:0%d", tm->tm_hour, tm->tm_min);
} else {
snprintf(buf, 32, "%d:%d", tm->tm_hour, tm->tm_min);
}
wr = strftime_append((char*)(s + written), remaining, buf);
written += wr;
remaining -= wr;
break;
}
p++;
} else {
if (remaining) {
s[written] = *p;
written++;
remaining--;
}
p++;
}
}
s[written] = '\0';
return written;
}