feat: create firmware skeleton and reproducible build

scripts/reproducible_time.c

@@ -0,0 +1,37 @@
+#define _GNU_SOURCE
+
+#include <stddef.h>
+#include <sys/syscall.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+static const time_t FIXED_TIME = 0;
+
+time_t time(time_t *result)
+{
+    if (result != NULL) {
+        *result = FIXED_TIME;
+    }
+    return FIXED_TIME;
+}
+
+int gettimeofday(struct timeval *value, void *timezone)
+{
+    (void)timezone;
+    if (value != NULL) {
+        value->tv_sec = FIXED_TIME;
+        value->tv_usec = 0;
+    }
+    return 0;
+}
+
+int clock_gettime(clockid_t clock_id, struct timespec *value)
+{
+    if (clock_id == CLOCK_REALTIME) {
+        value->tv_sec = FIXED_TIME;
+        value->tv_nsec = 0;
+        return 0;
+    }
+    return (int)syscall(SYS_clock_gettime, clock_id, value);
+}