Ruby for NaCl. Please assign the appropriate reviewer.

tests/ruby/main.c

+/* Copyright 2009 The Native Client Authors.  All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can
+ * be found in the LICENSE file. */
+
+#include <stdio.h>
+#include <string.h>
+#include <nacl/nacl_srpc.h>
+#include "ruby-1.8.6-p368/ruby.h"
+
+int initialized = 0;
+
+char* INIT_RUBY_SCRIPT =
+    "$stdout_default = $stdout \n"
+    "class Logger \n"
+    "  def initialize() \n"
+    "    @strings = [] \n"
+    "  end \n"
+    "\n"
+    "  def write(s) \n"
+    "    @strings.push(s) \n"
+    "    $stdout_default.write s \n"
+    "  end \n"
+    "\n"
+    "  def get_string() \n"
+    "    current = @strings \n"
+    "    @strings = [] \n"
+    "    return current.join("") \n"
+    "  end \n"
+    "end \n"
+    "\n"
+    "$stdout_logger = Logger.new \n"
+    "$stdout = $stdout_logger \n";
+
+/*
+ *  Evals Ruby expression and returns stdout updates.
+ */
+NaClSrpcError RubyEval(NaClSrpcChannel *channel,
+    NaClSrpcArg **in_args, NaClSrpcArg **out_args) {
+
+  /* TODO(krasin): MAKE IT THREAD-SAFE */
+  if (!initialized) {
+    ruby_init();
+    rb_eval_string(INIT_RUBY_SCRIPT);
+    initialized = 1;
+  }
+  rb_eval_string(in_args[0]->u.sval);
+  VALUE result = rb_eval_string("$stdout_logger.get_string()");
+
+  /*
+   * Strdup must be used because the SRPC layer frees the string passed to it.
+   */
+  out_args[0]->u.sval = strdup(StringValuePtr(result));
+
+  return NACL_SRPC_RESULT_OK;
+}
+
+/*
+ * Export the method as taking no arguments and returning one integer.
+ */
+NACL_SRPC_METHOD("rubyEval:s:s", RubyEval);