Compiler for the JSON Traversal Language.

chrome/tools/profile_reset/jtl_compiler.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_TOOLS_PROFILE_RESET_JTL_COMPILER_H_
+#define CHROME_TOOLS_PROFILE_RESET_JTL_COMPILER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+
+// Compiles text-based JTL source code into JTL byte-code.
+//
+// For an overview of JTL (JSON Traversal Language), and the exhaustive list of
+// instructions, please see "chrome/browser/profile_resetter/jtl_foundation.h".
+//
+// The text-based JTL syntax itself much resembles C/C++. A program consists of
+// zero or more sentences. Each sentence is terminated by a semi-colon (;), and
+// is composed of *one* or more operations, separated by forward slashes (/).
+//
+// Each operation resembles a C/C++ function call and consists of an instruction
+// name, and an optional argument list, which takes Boolean values and/or string
+// literals. The text-based instruction names are defined in "jtl_compiler.cc".
+//
+// Whitespace does not matter, except for inside string literals. C++-style,
+// double-slash-introduced comments are also supported.
+//
+// Example source code:
+//
+//   // Store "x"=true if path "foo.bar" is found.
+//   node("foo")/node("bar")/store_bool("x", true);
+//
+//   // Store "y"="1" if the above value is set.
+//   compare_stored_bool("x", true, false)/store_hash("y", "1");
+//
+class JtlCompiler {
+ public:
+  struct CompileError {
+    enum ErrorCode {
+      ERROR_NONE,
+      MISMATCHED_DOUBLE_QUOTES,
+      PARSING_ERROR,
+      INVALID_OPERATION_NAME,
+      INVALID_ARGUMENT_COUNT,
+      INVALID_ARGUMENT_TYPE
+    };
+
+    CompileError() : line_number(0), error_code(ERROR_NONE) {}
+    CompileError(size_t line_number,
+                 const std::string& context,
+                 ErrorCode error_code)
+        : line_number(line_number), context(context), error_code(error_code) {}
+
+    size_t line_number;  // 0-based.
+    std::string context;
+    ErrorCode error_code;
+  };
+
+  // Compiles text-based JTL source code contained in |source_code| into JTL
+  // byte-code to |output_bytecode|. Variable, node names, and string literals
+  // will be hashed using the seed in |hash_seed|.
+  // On success, returns true. Otherwise, returns false and fills |error| with
+  // more information (if it is non-NULL).
+  static bool Compile(const std::string& source_code,
+                      const std::string& hash_seed,
+                      std::string* output_bytecode,
+                      CompileError* error);
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(JtlCompiler);
+};
+
+#endif  // CHROME_TOOLS_PROFILE_RESET_JTL_COMPILER_H_