add automated usage mode to the repl

This is definitely not a stable thing, but it does feel slightly crimes
to put it as an experimental feature. Shrug, up for bikeshedding.

Change-Id: I6ef176e3dee6fb1cac9c0a7a60d553a2c63ea728

1 files changed, 22 insertions, 0 deletions

diff --git a/src/libcmd/repl-interacter.cc b/src/libcmd/repl-interacter.cc
index 18c1cad0f..829383add 100644
--- a/src/libcmd/repl-interacter.cc
+++ b/src/libcmd/repl-interacter.cc
@@ -1,4 +1,6 @@
 #include <cstdio>
+#include <iostream>
+#include <string>
 
 #ifdef READLINE
 #include <readline/history.h>
@@ -183,4 +185,24 @@ ReadlineLikeInteracter::~ReadlineLikeInteracter()
     write_history(historyFile.c_str());
 }
 
+AutomationInteracter::Guard AutomationInteracter::init(detail::ReplCompleterMixin *)
+{
+    return Guard([] {});
+}
+
+// ASCII ENQ character
+constexpr const char * automationPrompt = "\x05";
+
+bool AutomationInteracter::getLine(std::string & input, ReplPromptType promptType)
+{
+    std::cout << std::unitbuf;
+    std::cout << automationPrompt;
+    if (!std::getline(std::cin, input)) {
+        // reset failure bits on EOF
+        std::cin.clear();
+        return false;
+    }
+    return true;
+}
+
 };