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contrib/datetime/datetime_functions.c

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+/*
+ * datetime_functions.c --
+ *
+ * This file defines new functions for the time and date data types.
+ *
+ * Copyright (c) 1996, Massimo Dal Zotto <dz@cs.unitn.it>
+ */
+
+#include <time.h>
+
+#include "postgres.h"
+#include "pg_type.h"
+#include "utils/palloc.h"
+
+typedef struct DateADT {
+    char	day;
+    char	month;
+    short	year;
+} DateADT;
+
+typedef struct TimeADT {
+    short	hr;
+    short	min;
+    float	sec;
+} TimeADT;
+
+TimeADT *
+time_difference(TimeADT *time1, TimeADT *time2)
+{
+    TimeADT *time = (TimeADT*)palloc(sizeof(TimeADT));
+
+    time->sec = time1->sec - time2->sec;
+    time->min = time1->min - time2->min;
+    time->hr  = time1->hr  - time2->hr;
+
+    if (time->sec < 0) {
+	time->sec += 60.0;
+	time->min--;
+    } else if (time->sec >= 60.0) {
+	time->sec -= 60.0;
+	time->min++;
+    }
+
+    if (time->min < 0) {
+	time->min += 60;
+	time->hr--;
+    } else if (time->min >= 60) {
+	time->min -= 60;
+	time->hr++;
+    }
+
+    if (time->hr < 0) {
+	time->hr += 24;
+    } else if (time->hr >= 24) {
+	time->hr -= 24;
+    }
+
+    return (time);
+}
+
+TimeADT *
+currentTime()
+{
+    time_t current_time;
+    struct tm *tm;
+    TimeADT *result = (TimeADT*)palloc(sizeof(TimeADT));
+
+    current_time = time(NULL);
+    tm = localtime(&current_time);
+    result->sec = tm->tm_sec;
+    result->min = tm->tm_min;
+    result->hr  = tm->tm_hour;
+
+    return (result);
+}
+
+int4
+currentDate()
+{
+    time_t current_time;
+    struct tm *tm;
+    int4 result;
+    DateADT *date = (DateADT*)&result;
+
+    current_time = time(NULL);
+    tm = localtime(&current_time);
+    date->day   = tm->tm_mday;
+    date->month = tm->tm_mon+1;
+    date->year  = tm->tm_year+1900;
+
+    return (result);
+}
+
+int4
+hours(TimeADT *time)
+{
+    return (time->hr);
+}
+
+int4
+minutes(TimeADT *time)
+{
+    return (time->min);
+}
+
+int4
+seconds(TimeADT *time)
+{
+    int seconds = (int)time->sec;
+    return (seconds);
+}
+
+int4
+day(int4 val)
+{
+    DateADT *date = (DateADT*)&val;
+    return (date->day);
+}
+
+int4
+month(int4 val)
+{
+    DateADT *date = (DateADT*)&val;
+    return (date->month);
+}
+
+int4
+year(int4 val)
+{
+    DateADT *date = (DateADT*)&val;
+    return (date->year);
+}
+
+int4
+asMinutes(TimeADT *time)
+{
+    int seconds = (int)time->sec;
+    return (time->min + 60*time->hr);
+}
+
+int4
+asSeconds(TimeADT *time)
+{
+    int seconds = (int)time->sec;
+    return (seconds + 60*time->min + 3600*time->hr);
+}
+