Compiler for the JSON Traversal Language.

chrome/tools/profile_reset/jtl_compiler_frontend.cc

+// 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.
+//
+// A simple command-line compiler for JTL (JSON Traversal Language).
+//
+// Translates rules from a text-based, human-readable format to an easy-to-parse
+// byte-code format, which then can be interpreted by JtlInterpreter.
+//
+// Example usage:
+//   jtl_compiler --input=blah.txt --hash-seed="foobar" --output=blah.dat
+
+#include <iostream>
+#include <string>
+
+#include "base/command_line.h"
+#include "base/file_util.h"
+#include "base/files/file_path.h"
+#include "base/logging.h"
+#include "chrome/tools/profile_reset/jtl_compiler.h"
+
+namespace {
+
+// Command-line argument name: path to the input text-based JTL source code.
+const char kInputPath[] = "input";
+
+// Command-line argument name: path to the output byte-code.
+const char kOutputPath[] = "output";
+
+// Command-line argument name: the hash seed to use.
+const char kHashSeed[] = "hash-seed";
+
+// Error codes.
+const char kMismatchedDoubleQuotes[] = "Mismatched double-quotes before EOL.";
+const char kParsingError[] = "Parsing error. Input is ill-formed.";
+const char kArgumentCountError[] = "Wrong argument type(s) for operation.";
+const char kArgumentTypeError[] = "Wrong number of arguments for operation.";
+const char kUnknownOperationError[] = "No operation by this name.";
+const char kUnknownError[] = "Unknown error.";
+
+const char* ResolveErrorCode(JtlCompiler::CompileError::ErrorCode code) {
+  switch (code) {
+    case JtlCompiler::CompileError::MISMATCHED_DOUBLE_QUOTES:
+      return kMismatchedDoubleQuotes;
+    case JtlCompiler::CompileError::PARSING_ERROR:
+      return kParsingError;
+    case JtlCompiler::CompileError::INVALID_ARGUMENT_COUNT:
+      return kArgumentCountError;
+    case JtlCompiler::CompileError::INVALID_ARGUMENT_TYPE:
+      return kArgumentTypeError;
+    case JtlCompiler::CompileError::INVALID_OPERATION_NAME:
+      return kUnknownOperationError;
+    default:
+      return kUnknownError;
+  }
+}
+
+}  // namespace
+
+int main(int argc, char* argv[]) {
+  CommandLine::Init(argc, argv);
+  CommandLine* cmd_line = CommandLine::ForCurrentProcess();
+  if (!cmd_line->HasSwitch(kInputPath) || !cmd_line->HasSwitch(kHashSeed) ||
+      !cmd_line->HasSwitch(kOutputPath)) {
+    std::cerr << "Usage: " << argv[0] << " <options>" << std::endl;
+    std::cerr << "\nOptions are:" << std::endl;
+    std::cerr << "  --" << kInputPath << "=<file>"
+              << "\t\tPath to the input text-based JTL source code."
+              << std::endl;
+    std::cerr << "  --" << kOutputPath << "=<file>"
+              << "\t\tPath to the output byte-code." << std::endl;
+    std::cerr << "  --" << kHashSeed << "=<value>"
+              << "\t\tThe hash seed to use." << std::endl;
+    return -1;
+  }
+
+  base::FilePath source_code_path =
+      MakeAbsoluteFilePath(cmd_line->GetSwitchValuePath(kInputPath));
+  std::string source_code;
+  if (!base::ReadFileToString(source_code_path, &source_code)) {
+    LOG(ERROR) << "Error reading input file.";
+    return -3;
+  }
+
+  std::string bytecode;
+  JtlCompiler::CompileError error;
+  std::string hash_seed = cmd_line->GetSwitchValueASCII(kHashSeed);
+  if (!JtlCompiler::Compile(source_code, hash_seed, &bytecode, &error)) {
+    std::cerr << "Compile error. " << ResolveErrorCode(error.error_code)
+              << std::endl;
+    std::cerr << "  Line number:" << (error.line_number + 1) << std::endl;
+    std::cerr << "  Context:" << (error.context.size() > 63
+                                      ? error.context.substr(0, 60) + "..."
+                                      : error.context) << std::endl;
+    return -2;
+  }
+
+  base::FilePath bytecode_path =
+      MakeAbsoluteFilePath(cmd_line->GetSwitchValuePath(kOutputPath));
+  int bytes_written =
+      file_util::WriteFile(cmd_line->GetSwitchValuePath(kOutputPath),
+                           bytecode.data(),
+                           bytecode.size());
+  if (bytes_written != static_cast<int>(bytecode.size())) {
+    LOG(ERROR) << "Error writing output file.";
+    return -3;
+  }
+
+  return 0;
+}