Makefile: Rewrite for presubmit checks

The commit reorganizes the Makefile, so that "make check" can run on
each PR to detect any errors.

1 files changed, 14 insertions, 0 deletions

diff --git a/input_fail.py b/input_fail.py
new file mode 100755
index 0000000..67f5e74
--- /dev/null
+++ b/input_fail.py
@@ -0,0 +1,14 @@
+#!/usr/bin/env python
+
+# Exit with 1 if any input is provided. Print the input to stdout, unless an
+# argument is specified. In that case, print the argument.
+
+import sys
+
+input_string = sys.stdin.read()
+if input_string != "":
+    if len(sys.argv) >= 2:
+        print(sys.argv[1])
+    else:
+        sys.stdout.write(input_string)
+    sys.exit(1)