/* Return a newly allocated time zone for NAME, or NULL on failure. As a special case, return a nonzero constant for wall clock time, a constant that survives freeing. */ timezone_t tzalloc (char const *name) { size_t name_size = name ? strlen (name) + 1 : 0; size_t abbr_size = name_size < ABBR_SIZE_MIN ? ABBR_SIZE_MIN : name_size + 1; timezone_t tz = malloc (offsetof (struct tm_zone, abbrs) + abbr_size); if (tz) { tz->next = NULL; #if HAVE_TZNAME && !HAVE_TM_ZONE tz->tzname_copy[0] = tz->tzname_copy[1] = NULL; #endif tz->tz_is_set = !!name; extend_abbrs (tz->abbrs, name, name_size); } return tz; }
/* Save into TZ any nontrivial time zone abbreviation used by TM, and update *TM (if HAVE_TM_ZONE) or *TZ (if !HAVE_TM_ZONE && HAVE_TZNAME) if they use the abbreviation. Return true if successful, false (setting errno) otherwise. */ static bool save_abbr (timezone_t tz, struct tm *tm) { #if HAVE_TM_ZONE || HAVE_TZNAME char const *zone = NULL; char *zone_copy = (char *) ""; # if HAVE_TZNAME int tzname_index = -1; # endif # if HAVE_TM_ZONE zone = tm->tm_zone; # endif # if HAVE_TZNAME if (! (zone && *zone) && 0 <= tm->tm_isdst) { tzname_index = tm->tm_isdst != 0; zone = tzname[tzname_index]; } # endif /* No need to replace null zones, or zones within the struct tm. */ if (!zone || ((char *) tm <= zone && zone < (char *) (tm + 1))) return true; if (*zone) { zone_copy = tz->abbrs; while (strcmp (zone_copy, zone) != 0) { if (! (*zone_copy || (zone_copy == tz->abbrs && tz->tz_is_set))) { size_t zone_size = strlen (zone) + 1; if (zone_size < tz->abbrs + ABBR_SIZE_MIN - zone_copy) extend_abbrs (zone_copy, zone, zone_size); else { tz = tz->next = tzalloc (zone); if (!tz) return false; tz->tz_is_set = 0; zone_copy = tz->abbrs; } break; } zone_copy += strlen (zone_copy) + 1; if (!*zone_copy && tz->next) { tz = tz->next; zone_copy = tz->abbrs; } } } /* Replace the zone name so that its lifetime matches that of TZ. */ # if HAVE_TM_ZONE tm->tm_zone = zone_copy; # else if (0 <= tzname_index) tz->tzname_copy[tzname_index] = zone_copy; # endif #endif return true; }