rdate: Add a very basic implementation rdate

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

1 files changed, 62 insertions, 0 deletions

diff --git a/userland/minibox/utilities/sha1sum.c b/userland/minibox/utilities/sha1sum.c
new file mode 100644
index 0000000..9c98cc0
--- /dev/null
+++ b/userland/minibox/utilities/sha1sum.c
@@ -0,0 +1,62 @@
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <tb/sha1.h>
+#include <unistd.h>
+
+static int sha1_hash_file(const char *name, int fd) {
+  SHA1_CTX ctx;
+  SHA1_Init(&ctx);
+
+  for (;;) {
+    char buffer[4096];
+    int rc = read(fd, buffer, 4096);
+    if (-1 == rc) {
+      perror("read");
+      return 0;
+    }
+    if (0 == rc) {
+      break;
+    }
+    SHA1_Update(&ctx, buffer, rc);
+  }
+  unsigned char digest[SHA1_LEN];
+  SHA1_Final(&ctx, digest);
+
+  printf("%s: ", name);
+  for (int i = 0; i < SHA1_LEN; i++) {
+    printf("%02x", digest[i]);
+  }
+  printf("\n");
+  return 1;
+}
+
+int sha1sum_main(int argc, char **argv) {
+  int fd = STDIN_FILENO;
+
+  // If no file operands are specified, the standard input shall be
+  // used.
+  if (argc < 2) {
+    return (sha1_hash_file("-", 0)) ? 0 : 1;
+  }
+
+  argv++;
+  for (; *argv; argv++) {
+    if (0 == strcmp(*argv, "-")) {
+      if (!sha1_hash_file("-", 0)) {
+        return 1;
+      }
+      continue;
+    }
+
+    if (-1 == (fd = open(*argv, O_RDONLY, 0))) {
+      perror(*argv);
+      return 1;
+    }
+    if (!sha1_hash_file(*argv, fd)) {
+      return 1;
+    }
+    close(fd);
+  }
+  return 0;
+}