+: see if this is a values.h system
+set values.h i_values
+eval $inhdr
+
+: Check the max offset that gmtime and localtime accept
+echo "Checking max offsets that gmtime () accepts"
+
+case $i_values in
+ define) yyy="#include <values.h>" ;;
+ *) yyy="" ;;
+ esac
+
+case "$sGMTIME_min/$sGMTIME_max" in
+ 0/0|/)
+ $cat >try.c <<EOCP
+#include <sys/types.h>
+#include <stdio.h>
+#include <time.h>
+$yyy
+
+int i;
+struct tm *tmp;
+time_t pt;
+
+void gm_check (time_t t, int min_year, int max_year)
+{
+ tmp = gmtime (&t);
+ if ( tmp == NULL ||
+ /* Check tm_year overflow */
+ tmp->tm_year < min_year || tmp->tm_year > max_year)
+ tmp = NULL;
+ else
+ pt = t;
+ } /* gm_check */
+
+int check_max ()
+{
+ tmp = NULL;
+ pt = 0;
+#ifdef MAXLONG
+ gm_check (MAXLONG, 69, 0x7fffffff);
+#endif
+ if (tmp == NULL || tmp->tm_year < 0) {
+ for (i = 63; i >= 0; i--) {
+ time_t x = pt | ((time_t)1 << i);
+ if (x < 0 || x < pt) continue;
+ gm_check (x, 69, 0x7fffffff);
+ }
+ }
+ printf ("sGMTIME_max=%ld\n", pt);
+ return (0);
+ } /* check_max */
+
+int check_min ()
+{
+ tmp = NULL;
+ pt = 0;
+#ifdef MINLONG
+ gm_check (MINLONG, -1900, 70);
+#endif
+ if (tmp == NULL) {
+ for (i = 36; i >= 0; i--) {
+ time_t x = pt - ((time_t)1 << i);
+ if (x > 0) continue;
+ gm_check (x, -1900, 70);
+ }
+ }
+ printf ("sGMTIME_min=%ld\n", pt);
+ return (0);
+ } /* check_min */
+
+int main (int argc, char *argv[])
+{
+ fprintf (stderr, "Sizeof time_t = %ld\n", sizeof (time_t));
+ check_max ();
+ check_min ();
+ return (0);
+ } /* main */
+EOCP
+ set try
+ if eval $compile; then
+ eval `$run ./try`
+ else
+ echo "Cannot determine sGMTIME_max and sGMTIME_min." >&4
+ fi
+ $rm_try
+ ;;
+ esac
+
+echo "Checking max offsets that localtime () accepts"
+
+case "$sLOCALTIME_min/$sLOCALTIME_max" in
+ 0/0|/)
+ $cat >try.c <<EOCP
+#include <sys/types.h>
+#include <stdio.h>
+#include <time.h>
+$yyy
+
+int i;
+struct tm *tmp;
+time_t pt;
+
+void local_check (time_t t, int min_year, int max_year)
+{
+ if (sizeof (time_t) > 4 && t > 0x7ffffffffffff000LL)
+ tmp = NULL;
+ else
+ tmp = localtime (&t);
+ if ( tmp == NULL ||
+ /* Check tm_year overflow */
+ tmp->tm_year < min_year || tmp->tm_year > max_year)
+ tmp = NULL;
+ else
+ pt = t;
+ } /* local_check */
+
+int check_max ()
+{
+ tmp = NULL;
+ pt = 0;
+#ifdef MAXLONG
+ local_check (MAXLONG, 69, 0x7fffffff);
+#endif
+ if (tmp == NULL || tmp->tm_year < 0) {
+ for (i = 63; i >= 0; i--) {
+ time_t x = pt | ((time_t)1 << i);
+ if (x < 0 || x < pt) continue;
+ local_check (x, 69, 0x7fffffff);
+ }
+ }
+ printf ("sLOCALTIME_max=%ld\n", pt);
+ return (0);
+ } /* check_max */
+
+int check_min ()
+{
+ tmp = NULL;
+ pt = 0;
+#ifdef MINLONG
+ local_check (MINLONG, -1900, 70);
+#endif
+ if (tmp == NULL) {
+ for (i = 36; i >= 0; i--) {
+ time_t x = pt - ((time_t)1 << i);
+ if (x > 0) continue;
+ local_check (x, -1900, 70);
+ }
+ }
+ printf ("sLOCALTIME_min=%ld\n", pt);
+ return (0);
+ } /* check_min */
+
+int main (int argc, char *argv[])
+{
+ check_max ();
+ check_min ();
+ return (0);
+ } /* main */
+EOCP
+ set try
+ if eval $compile; then
+ eval `$run ./try`
+ else
+ echo "Cannot determine sLOCALTIME_max and sLOCALTIME_min." >&4
+ fi
+ $rm_try
+ ;;
+ esac
+
+: check for type of arguments to select.
https://perl5.git.perl.org / perl5.git / blobdiff