timestamp.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

					{
						char		tmp[4] = "%Ex";

						p++;
						if (*p == '\0')
							return -1;
						tmp[2] = *p;
						/* XXX: fall back to strftime */

						/*
						 * strftime's month is 0 based, ours is 1 based
						 */
						tm->tm_mon -= 1;
						i = strftime(q, *pstr_len, tmp, tm);
						if (i == 0)
							return -1;
						while (*q)
						{
							q++;
							(*pstr_len)--;
						}
						tm->tm_mon += 1;
						replace_type = PGTYPES_TYPE_NOTHING;
						break;
					}
				case 'G':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%G", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'g':
					/* XXX: fall back to strftime */
					{
						char	   *fmt = "%g"; /* Keep compiler quiet about
												 * 2-digit year */

						tm->tm_mon -= 1;
						i = strftime(q, *pstr_len, fmt, tm);
						if (i == 0)
							return -1;
						while (*q)
						{
							q++;
							(*pstr_len)--;
						}
						tm->tm_mon += 1;
						replace_type = PGTYPES_TYPE_NOTHING;
					}
					break;
				case 'H':
					replace_val.uint_val = tm->tm_hour;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 'I':
					replace_val.uint_val = tm->tm_hour % 12;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 'j':
					replace_val.uint_val = tm->tm_yday;
					replace_type = PGTYPES_TYPE_UINT_3_LZ;
					break;
				case 'k':
					replace_val.uint_val = tm->tm_hour;
					replace_type = PGTYPES_TYPE_UINT_2_LS;
					break;
				case 'l':
					replace_val.uint_val = tm->tm_hour % 12;
					replace_type = PGTYPES_TYPE_UINT_2_LS;
					break;
				case 'm':
					replace_val.uint_val = tm->tm_mon;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 'M':
					replace_val.uint_val = tm->tm_min;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 'n':
					replace_val.char_val = '\n';
					replace_type = PGTYPES_TYPE_CHAR;
					break;
				case 'p':
					if (tm->tm_hour < 12)
						replace_val.str_val = "AM";
					else
						replace_val.str_val = "PM";
					replace_type = PGTYPES_TYPE_STRING_CONSTANT;
					break;
				case 'P':
					if (tm->tm_hour < 12)
						replace_val.str_val = "am";
					else
						replace_val.str_val = "pm";
					replace_type = PGTYPES_TYPE_STRING_CONSTANT;
					break;
				case 'r':
					i = dttofmtasc_replace(ts, dDate, dow, tm,
										   q, pstr_len,
										   "%I:%M:%S %p");
					if (i)
						return i;
					break;
				case 'R':
					i = dttofmtasc_replace(ts, dDate, dow, tm,
										   q, pstr_len,
										   "%H:%M");
					if (i)
						return i;
					break;
				case 's':
#ifdef HAVE_INT64_TIMESTAMP
					replace_val.int64_val = (*ts - SetEpochTimestamp()) / 1000000.0;
					replace_type = PGTYPES_TYPE_INT64;
#else
					replace_val.double_val = *ts - SetEpochTimestamp();
					replace_type = PGTYPES_TYPE_DOUBLE_NF;
#endif
					break;
				case 'S':
					replace_val.uint_val = tm->tm_sec;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 't':
					replace_val.char_val = '\t';
					replace_type = PGTYPES_TYPE_CHAR;
					break;
				case 'T':
					i = dttofmtasc_replace(ts, dDate, dow, tm,
										   q, pstr_len,
										   "%H:%M:%S");
					if (i)
						return i;
					break;
				case 'u':
					if (dow == 0)
						dow = 7;
					replace_val.uint_val = dow;
					replace_type = PGTYPES_TYPE_UINT;
					break;
				case 'U':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%U", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'V':
					/* XXX: fall back to strftime */
					i = strftime(q, *pstr_len, "%V", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'w':
					replace_val.uint_val = dow;
					replace_type = PGTYPES_TYPE_UINT;
					break;
				case 'W':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%U", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'x':
					/* XXX: fall back to strftime */
					{
						char	   *fmt = "%x"; /* Keep compiler quiet about
												 * 2-digit year */

						tm->tm_mon -= 1;
						i = strftime(q, *pstr_len, fmt, tm);
						if (i == 0)
							return -1;
						while (*q)
						{
							q++;
							(*pstr_len)--;
						}
						tm->tm_mon += 1;
						replace_type = PGTYPES_TYPE_NOTHING;
					}
					break;
				case 'X':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%X", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'y':
					replace_val.uint_val = tm->tm_year % 100;
					replace_type = PGTYPES_TYPE_UINT_2_LZ;
					break;
				case 'Y':
					replace_val.uint_val = tm->tm_year;
					replace_type = PGTYPES_TYPE_UINT;
					break;
				case 'z':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%z", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case 'Z':
					/* XXX: fall back to strftime */
					tm->tm_mon -= 1;
					i = strftime(q, *pstr_len, "%Z", tm);
					if (i == 0)
						return -1;
					while (*q)
					{
						q++;
						(*pstr_len)--;
					}
					tm->tm_mon += 1;
					replace_type = PGTYPES_TYPE_NOTHING;
					break;
				case '%':
					replace_val.char_val = '%';
					replace_type = PGTYPES_TYPE_CHAR;
					break;
				case '\0':
					/* fmtstr: blabla%' */

					/*
					 * this is not compliant to the specification
					 */
					return -1;
				default:

					/*
					 * if we don't know the pattern, we just copy it
					 */
					if (*pstr_len > 1)
					{
						*q = '%';
						q++;
						(*pstr_len)--;
						if (*pstr_len > 1)
						{
							*q = *p;
							q++;
							(*pstr_len)--;
						}
						else
						{
							*q = '\0';
							return -1;
						}
						*q = '\0';
					}
					else
						return -1;
					break;
			}
			i = pgtypes_fmt_replace(replace_val, replace_type, &q, pstr_len);
			if (i)
				return i;
		}
		else
		{
			if (*pstr_len > 1)
			{
				*q = *p;
				(*pstr_len)--;
				q++;
				*q = '\0';
			}
			else
				return -1;
		}
		p++;
	}
	return 0;
}


int
PGTYPEStimestamp_fmt_asc(timestamp * ts, char *output, int str_len, char *fmtstr)
{
	struct tm	tm;
	fsec_t		fsec;
	date		dDate;
	int			dow;

	dDate = PGTYPESdate_from_timestamp(*ts);
	dow = PGTYPESdate_dayofweek(dDate);
	timestamp2tm(*ts, NULL, &tm, &fsec, NULL);

	return dttofmtasc_replace(ts, dDate, dow, &tm, output, &str_len, fmtstr);
}

int
PGTYPEStimestamp_sub(timestamp * ts1, timestamp * ts2, interval * iv)
{
	if (TIMESTAMP_NOT_FINITE(*ts1) || TIMESTAMP_NOT_FINITE(*ts2))
		return PGTYPES_TS_ERR_EINFTIME;
	else
		iv->time = (ts1 - ts2);

	iv->month = 0;

	return 0;
}

int
PGTYPEStimestamp_defmt_asc(char *str, char *fmt, timestamp * d)
{
	int			year,
				month,
				day;
	int			hour,
				minute,
				second;
	int			tz;

	int			i;
	char	   *mstr;
	char	   *mfmt;

	if (!fmt)
		fmt = "%Y-%m-%d %H:%M:%S";
	if (!fmt[0])
		return 1;

	mstr = pgtypes_strdup(str);
	mfmt = pgtypes_strdup(fmt);

	/*
	 * initialize with impossible values so that we can see if the fields
	 * where specified at all
	 */
	/* XXX ambiguity with 1 BC for year? */
	year = -1;
	month = -1;
	day = -1;
	hour = 0;
	minute = -1;
	second = -1;
	tz = 0;

	i = PGTYPEStimestamp_defmt_scan(&mstr, mfmt, d, &year, &month, &day, &hour, &minute, &second, &tz);
	free(mstr);
	free(mfmt);
	return i;
}

/*
* add an interval to a time stamp
*
*	*tout = tin + span
*
*	 returns 0 if successful
*	 returns -1 if it fails
*
*/

int
PGTYPEStimestamp_add_interval(timestamp * tin, interval * span, timestamp * tout)
{


	if (TIMESTAMP_NOT_FINITE(*tin))
		*tout = *tin;


	else
	{
		if (span->month != 0)
		{
			struct tm	tt,
					   *tm = &tt;
			fsec_t		fsec;


			if (timestamp2tm(*tin, NULL, tm, &fsec, NULL) != 0)
				return -1;
			tm->tm_mon += span->month;
			if (tm->tm_mon > MONTHS_PER_YEAR)
			{
				tm->tm_year += (tm->tm_mon - 1) / MONTHS_PER_YEAR;
				tm->tm_mon = (tm->tm_mon - 1) % MONTHS_PER_YEAR + 1;
			}
			else if (tm->tm_mon < 1)
			{
				tm->tm_year += tm->tm_mon / MONTHS_PER_YEAR - 1;
				tm->tm_mon = tm->tm_mon % MONTHS_PER_YEAR + MONTHS_PER_YEAR;
			}


			/* adjust for end of month boundary problems... */
			if (tm->tm_mday > day_tab[isleap(tm->tm_year)][tm->tm_mon - 1])
				tm->tm_mday = (day_tab[isleap(tm->tm_year)][tm->tm_mon - 1]);


			if (tm2timestamp(tm, fsec, NULL, tin) != 0)
				return -1;
		}


		*tin += span->time;
		*tout = *tin;
	}
	return 0;

}


/*
* subtract an interval from a time stamp
*
*	*tout = tin - span
*
*	 returns 0 if successful
*	 returns -1 if it fails
*
*/

int
PGTYPEStimestamp_sub_interval(timestamp * tin, interval * span, timestamp * tout)
{
	interval	tspan;

	tspan.month = -span->month;
	tspan.time = -span->time;


	return PGTYPEStimestamp_add_interval(tin, &tspan, tout);
}