Added library to change the time.

tests/common/time_past.c

@@ -0,0 +1,52 @@
+/* 
+ * gcc time_past.c -o time_past.so -shared -ldl 
+ * LD_PRELOAD=./time_past.so PAST_DAYS=2 ./test
+ */
+
+#define _GNU_SOURCE
+#include <dlfcn.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdarg.h>
+#include <fcntl.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+typedef time_t (*time_type) (time_t *t);
+static time_type next_time;
+
+static int time_past = 0;
+static char *past = NULL;
+
+time_t time (time_t *t)
+{
+	time_t res;
+
+	if (NULL == next_time)
+	{
+		next_time = dlsym (RTLD_NEXT, "time");
+		assert (NULL != next_time);
+	}
+	if (NULL == past) {
+		const char *past = getenv ("PAST_DAYS");
+		if (NULL == past) {
+			fputs ("No PAST_DAYS defined\n", stderr);
+		}
+		time_past = atoi (past);
+	}
+
+	res = next_time (t);
+	res -= 24*60*60*time_past;
+
+	if (NULL != t) {
+		*t = res;
+	}
+
+	return res;
+}
+