rdate: Add a very basic implementation rdate

Also adds sha1sum.c file which I forgot in a previous commit

1 files changed, 50 insertions, 0 deletions

diff --git a/userland/minibox/utilities/rdate.c b/userland/minibox/utilities/rdate.c
new file mode 100644
index 0000000..11398c8
--- /dev/null
+++ b/userland/minibox/utilities/rdate.c
@@ -0,0 +1,50 @@
+#include <arpa/inet.h>
+#include <assert.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/socket.h>
+
+int rdate_main(int argc, char **argv) {
+  int fd = socket(AF_INET, SOCK_STREAM, 0);
+  if (fd < 0) {
+    perror("socket");
+    return 1;
+  }
+
+  struct addrinfo *result = NULL;
+  struct addrinfo hints;
+  memset(&hints, 0, sizeof(hints));
+  hints.ai_socktype = SOCK_STREAM;
+  hints.ai_protocol = 0;
+  hints.ai_canonname = NULL;
+  hints.ai_addr = NULL;
+  hints.ai_next = NULL;
+
+  int rc = getaddrinfo("time-d-g.nist.gov", "37", &hints, &result);
+  if (-1 == rc) {
+    fprintf(stderr, "Error in getaddrinfo()\n");
+    return 1;
+  }
+
+  if (connect(fd, (struct sockaddr *)result->ai_addr, result->ai_addrlen) < 0) {
+    perror("connect");
+    return 1;
+  }
+
+  uint32_t t;
+  read(fd, &t, sizeof(t));
+  t = ntohl(t);
+
+  close(fd);
+
+  int64_t unix_time = (t - 2208988800) * 1000;
+  int clock_fd = open("/dev/clock", O_RDWR);
+  int64_t current;
+  read(clock_fd, &current, sizeof(int64_t));
+  write(clock_fd, &unix_time, sizeof(int64_t));
+  int64_t delta = (current / 1000) - (unix_time / 1000);
+  printf("delta: %d\n", delta);
+  return 0;
+}