1 files changed, 105 insertions, 0 deletions
diff --git a/contrib/awk/awklib/eg/lib/mktime.awk b/contrib/awk/awklib/eg/lib/mktime.awk
new file mode 100644
index 0000000..57ff20e
--- /dev/null
+++ b/contrib/awk/awklib/eg/lib/mktime.awk
@@ -0,0 +1,105 @@
+# mktime.awk --- convert a canonical date representation
+#                into a timestamp
+# Arnold Robbins, arnold@gnu.org, Public Domain
+# May 1993
+
+BEGIN    \
+{
+    # Initialize table of month lengths
+    _tm_months[0,1] = _tm_months[1,1] = 31
+    _tm_months[0,2] = 28; _tm_months[1,2] = 29
+    _tm_months[0,3] = _tm_months[1,3] = 31
+    _tm_months[0,4] = _tm_months[1,4] = 30
+    _tm_months[0,5] = _tm_months[1,5] = 31
+    _tm_months[0,6] = _tm_months[1,6] = 30
+    _tm_months[0,7] = _tm_months[1,7] = 31
+    _tm_months[0,8] = _tm_months[1,8] = 31
+    _tm_months[0,9] = _tm_months[1,9] = 30
+    _tm_months[0,10] = _tm_months[1,10] = 31
+    _tm_months[0,11] = _tm_months[1,11] = 30
+    _tm_months[0,12] = _tm_months[1,12] = 31
+}
+# decide if a year is a leap year
+function _tm_isleap(year,    ret)
+{
+    ret = (year % 4 == 0 && year % 100 != 0) ||
+            (year % 400 == 0)
+
+    return ret
+}
+# convert a date into seconds
+function _tm_addup(a,    total, yearsecs, daysecs,
+                         hoursecs, i, j)
+{
+    hoursecs = 60 * 60
+    daysecs = 24 * hoursecs
+    yearsecs = 365 * daysecs
+
+    total = (a[1] - 1970) * yearsecs
+
+    # extra day for leap years
+    for (i = 1970; i < a[1]; i++)
+        if (_tm_isleap(i))
+            total += daysecs
+
+    j = _tm_isleap(a[1])
+    for (i = 1; i < a[2]; i++)
+        total += _tm_months[j, i] * daysecs
+
+    total += (a[3] - 1) * daysecs
+    total += a[4] * hoursecs
+    total += a[5] * 60
+    total += a[6]
+
+    return total
+}
+# mktime --- convert a date into seconds,
+#            compensate for time zone
+
+function mktime(str,    res1, res2, a, b, i, j, t, diff)
+{
+    i = split(str, a, " ")    # don't rely on FS
+
+    if (i != 6)
+        return -1
+
+    # force numeric
+    for (j in a)
+        a[j] += 0
+
+    # validate
+    if (a[1] < 1970 ||
+        a[2] < 1 || a[2] > 12 ||
+        a[3] < 1 || a[3] > 31 ||
+        a[4] < 0 || a[4] > 23 ||
+        a[5] < 0 || a[5] > 59 ||
+        a[6] < 0 || a[6] > 60 )
+            return -1
+
+    res1 = _tm_addup(a)
+    t = strftime("%Y %m %d %H %M %S", res1)
+
+    if (_tm_debug)
+        printf("(%s) -> (%s)\n", str, t) > "/dev/stderr"
+
+    split(t, b, " ")
+    res2 = _tm_addup(b)
+
+    diff = res1 - res2
+
+    if (_tm_debug)
+        printf("diff = %d seconds\n", diff) > "/dev/stderr"
+
+    res1 += diff
+
+    return res1
+}
+BEGIN  {
+    if (_tm_test) {
+        printf "Enter date as yyyy mm dd hh mm ss: "
+        getline _tm_test_date
+        t = mktime(_tm_test_date)
+        r = strftime("%Y %m %d %H %M %S", t)
+        printf "Got back (%s)\n", r
+    }
+}