libfdatetime_floatingtime_copy_to_utf8_string: Midnight on first day of month not working

[siliconforks]

Consider the following program:

#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

#include <libfdatetime.h>

void test_date(double days) {
  union {
    double x;
    uint64_t i;
  } u;

  u.x = days;

  libfdatetime_floatingtime_t * floatingtime = NULL;
  if (libfdatetime_floatingtime_initialize(&floatingtime, NULL) != 1) {
    fprintf(stderr, "libfdatetime_floatingtime_initialize failed\n");
    exit(EXIT_FAILURE);
  }

  if (libfdatetime_floatingtime_copy_from_64bit(floatingtime, u.i, NULL) != 1) {
    fprintf(stderr, "libfdatetime_floatingtime_copy_from_64bit failed\n");
    exit(EXIT_FAILURE);
  }

  uint8_t date_time_string[32];
  if (libfdatetime_floatingtime_copy_to_utf8_string(floatingtime,
        date_time_string, 32, LIBFDATETIME_STRING_FORMAT_TYPE_CTIME |
        LIBFDATETIME_STRING_FORMAT_FLAG_DATE_TIME_NANO_SECONDS, NULL) != 1) {
    fprintf(stderr, "libfdatetime_floatingtime_copy_to_utf8_string failed\n");
    exit(EXIT_FAILURE);
  }

  printf("%f %" PRIx64 " %s\n", u.x, u.i, date_time_string);

  libfdatetime_floatingtime_free(&floatingtime, NULL);
}

int main(void) {
  for (double d = 45400; d < 45430; ++d) {
    test_date(d);
  }
  return 0;
}

This generates the following output:

45400.000000 40e62b0000000000 Apr 18, 2024 00:00:00.000000000
45401.000000 40e62b2000000000 Apr 19, 2024 00:00:00.000000000
45402.000000 40e62b4000000000 Apr 20, 2024 00:00:00.000000000
45403.000000 40e62b6000000000 Apr 21, 2024 00:00:00.000000000
45404.000000 40e62b8000000000 Apr 22, 2024 00:00:00.000000000
45405.000000 40e62ba000000000 Apr 23, 2024 00:00:00.000000000
45406.000000 40e62bc000000000 Apr 24, 2024 00:00:00.000000000
45407.000000 40e62be000000000 Apr 25, 2024 00:00:00.000000000
45408.000000 40e62c0000000000 Apr 26, 2024 00:00:00.000000000
45409.000000 40e62c2000000000 Apr 27, 2024 00:00:00.000000000
45410.000000 40e62c4000000000 Apr 28, 2024 00:00:00.000000000
45411.000000 40e62c6000000000 Apr 29, 2024 00:00:00.000000000
45412.000000 40e62c8000000000 Apr 30, 2024 00:00:00.000000000
45413.000000 40e62ca000000000 (0x40e62ca000000000)
45414.000000 40e62cc000000000 May 02, 2024 00:00:00.000000000
45415.000000 40e62ce000000000 May 03, 2024 00:00:00.000000000
45416.000000 40e62d0000000000 May 04, 2024 00:00:00.000000000
45417.000000 40e62d2000000000 May 05, 2024 00:00:00.000000000
45418.000000 40e62d4000000000 May 06, 2024 00:00:00.000000000
45419.000000 40e62d6000000000 May 07, 2024 00:00:00.000000000
45420.000000 40e62d8000000000 May 08, 2024 00:00:00.000000000
45421.000000 40e62da000000000 May 09, 2024 00:00:00.000000000
45422.000000 40e62dc000000000 May 10, 2024 00:00:00.000000000
45423.000000 40e62de000000000 May 11, 2024 00:00:00.000000000
45424.000000 40e62e0000000000 May 12, 2024 00:00:00.000000000
45425.000000 40e62e2000000000 May 13, 2024 00:00:00.000000000
45426.000000 40e62e4000000000 May 14, 2024 00:00:00.000000000
45427.000000 40e62e6000000000 May 15, 2024 00:00:00.000000000
45428.000000 40e62e8000000000 May 16, 2024 00:00:00.000000000
45429.000000 40e62ea000000000 May 17, 2024 00:00:00.000000000

The first day of the month is not working.

[joachimmetz]

Thanks for flagging, I'll have a closer look when time permits