Shell.java revision 1621:1d7aaa18e5e5
1/* 2 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package jdk.nashorn.tools; 27 28import jdk.nashorn.api.scripting.NashornException; 29import jdk.nashorn.internal.codegen.Compiler; 30import jdk.nashorn.internal.codegen.Compiler.CompilationPhases; 31import jdk.nashorn.internal.ir.Expression; 32import jdk.nashorn.internal.ir.FunctionNode; 33import jdk.nashorn.internal.ir.debug.ASTWriter; 34import jdk.nashorn.internal.ir.debug.PrintVisitor; 35import jdk.nashorn.internal.objects.Global; 36import jdk.nashorn.internal.objects.NativeSymbol; 37import jdk.nashorn.internal.parser.Parser; 38import jdk.nashorn.internal.runtime.Context; 39import jdk.nashorn.internal.runtime.ErrorManager; 40import jdk.nashorn.internal.runtime.JSType; 41import jdk.nashorn.internal.runtime.Property; 42import jdk.nashorn.internal.runtime.ScriptEnvironment; 43import jdk.nashorn.internal.runtime.ScriptFunction; 44import jdk.nashorn.internal.runtime.ScriptObject; 45import jdk.nashorn.internal.runtime.ScriptRuntime; 46import jdk.nashorn.internal.runtime.ScriptingFunctions; 47import jdk.nashorn.internal.runtime.Symbol; 48import jdk.nashorn.internal.runtime.arrays.ArrayLikeIterator; 49import jdk.nashorn.internal.runtime.options.Options; 50 51import java.io.BufferedReader; 52import java.io.File; 53import java.io.FileReader; 54import java.io.IOException; 55import java.io.InputStream; 56import java.io.InputStreamReader; 57import java.io.OutputStream; 58import java.io.PrintStream; 59import java.io.PrintWriter; 60import java.io.StreamTokenizer; 61import java.io.StringReader; 62import java.nio.file.Files; 63import java.nio.file.Path; 64import java.nio.file.Paths; 65import java.util.ArrayList; 66import java.util.Arrays; 67import java.util.Iterator; 68import java.util.List; 69import java.util.Locale; 70import java.util.ResourceBundle; 71 72import static jdk.nashorn.internal.runtime.Source.sourceFor; 73 74/** 75 * Command line Shell for processing JavaScript files. 76 */ 77public class Shell implements PartialParser { 78 79 /** 80 * Resource name for properties file 81 */ 82 private static final String MESSAGE_RESOURCE = "jdk.nashorn.tools.resources.Shell"; 83 /** 84 * Shell message bundle. 85 */ 86 protected static final ResourceBundle bundle = ResourceBundle.getBundle(MESSAGE_RESOURCE, Locale.getDefault()); 87 88 /** 89 * Exit code for command line tool - successful 90 */ 91 public static final int SUCCESS = 0; 92 /** 93 * Exit code for command line tool - error on command line 94 */ 95 public static final int COMMANDLINE_ERROR = 100; 96 /** 97 * Exit code for command line tool - error compiling script 98 */ 99 public static final int COMPILATION_ERROR = 101; 100 /** 101 * Exit code for command line tool - error during runtime 102 */ 103 public static final int RUNTIME_ERROR = 102; 104 /** 105 * Exit code for command line tool - i/o error 106 */ 107 public static final int IO_ERROR = 103; 108 /** 109 * Exit code for command line tool - internal error 110 */ 111 public static final int INTERNAL_ERROR = 104; 112 113 /** 114 * Constructor 115 */ 116 protected Shell() { 117 } 118 119 /** 120 * Main entry point with the default input, output and error streams. 121 * 122 * @param args The command line arguments 123 */ 124 public static void main(final String[] args) { 125 try { 126 final int exitCode = main(System.in, System.out, System.err, args); 127 if (exitCode != SUCCESS) { 128 System.exit(exitCode); 129 } 130 } catch (final IOException e) { 131 System.err.println(e); //bootstrapping, Context.err may not exist 132 System.exit(IO_ERROR); 133 } 134 } 135 136 /** 137 * Starting point for executing a {@code Shell}. Starts a shell with the 138 * given arguments and streams and lets it run until exit. 139 * 140 * @param in input stream for Shell 141 * @param out output stream for Shell 142 * @param err error stream for Shell 143 * @param args arguments to Shell 144 * 145 * @return exit code 146 * 147 * @throws IOException if there's a problem setting up the streams 148 */ 149 public static int main(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) throws IOException { 150 return new Shell().run(in, out, err, args); 151 } 152 153 /** 154 * Run method logic. 155 * 156 * @param in input stream for Shell 157 * @param out output stream for Shell 158 * @param err error stream for Shell 159 * @param args arguments to Shell 160 * 161 * @return exit code 162 * 163 * @throws IOException if there's a problem setting up the streams 164 */ 165 protected final int run(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) throws IOException { 166 final Context context = makeContext(in, out, err, args); 167 if (context == null) { 168 return COMMANDLINE_ERROR; 169 } 170 171 final Global global = context.createGlobal(); 172 final ScriptEnvironment env = context.getEnv(); 173 final List<String> files = env.getFiles(); 174 if (files.isEmpty()) { 175 return readEvalPrint(context, global); 176 } 177 178 if (env._compile_only) { 179 return compileScripts(context, global, files); 180 } 181 182 if (env._fx) { 183 return runFXScripts(context, global, files); 184 } 185 186 return runScripts(context, global, files); 187 } 188 189 /** 190 * Make a new Nashorn Context to compile and/or run JavaScript files. 191 * 192 * @param in input stream for Shell 193 * @param out output stream for Shell 194 * @param err error stream for Shell 195 * @param args arguments to Shell 196 * 197 * @return null if there are problems with option parsing. 198 */ 199 private static Context makeContext(final InputStream in, final OutputStream out, final OutputStream err, final String[] args) { 200 final PrintStream pout = out instanceof PrintStream ? (PrintStream) out : new PrintStream(out); 201 final PrintStream perr = err instanceof PrintStream ? (PrintStream) err : new PrintStream(err); 202 final PrintWriter wout = new PrintWriter(pout, true); 203 final PrintWriter werr = new PrintWriter(perr, true); 204 205 // Set up error handler. 206 final ErrorManager errors = new ErrorManager(werr); 207 // Set up options. 208 final Options options = new Options("nashorn", werr); 209 210 // parse options 211 if (args != null) { 212 try { 213 final String[] prepArgs = preprocessArgs(args); 214 options.process(prepArgs); 215 } catch (final IllegalArgumentException e) { 216 werr.println(bundle.getString("shell.usage")); 217 options.displayHelp(e); 218 return null; 219 } 220 } 221 222 // detect scripting mode by any source's first character being '#' 223 if (!options.getBoolean("scripting")) { 224 for (final String fileName : options.getFiles()) { 225 final File firstFile = new File(fileName); 226 if (firstFile.isFile()) { 227 try (final FileReader fr = new FileReader(firstFile)) { 228 final int firstChar = fr.read(); 229 // starts with '# 230 if (firstChar == '#') { 231 options.set("scripting", true); 232 break; 233 } 234 } catch (final IOException e) { 235 // ignore this. File IO errors will be reported later anyway 236 } 237 } 238 } 239 } 240 241 return new Context(options, errors, wout, werr, Thread.currentThread().getContextClassLoader()); 242 } 243 244 /** 245 * Preprocess the command line arguments passed in by the shell. This method checks, for the first non-option 246 * argument, whether the file denoted by it begins with a shebang line. If so, it is assumed that execution in 247 * shebang mode is intended. The consequence of this is that the identified script file will be treated as the 248 * <em>only</em> script file, and all subsequent arguments will be regarded as arguments to the script. 249 * <p> 250 * This method canonicalizes the command line arguments to the form {@code <options> <script> -- <arguments>} if a 251 * shebang script is identified. On platforms that pass shebang arguments as single strings, the shebang arguments 252 * will be broken down into single arguments; whitespace is used as separator. 253 * <p> 254 * Shebang mode is entered regardless of whether the script is actually run directly from the shell, or indirectly 255 * via the {@code jjs} executable. It is the user's / script author's responsibility to ensure that the arguments 256 * given on the shebang line do not lead to a malformed argument sequence. In particular, the shebang arguments 257 * should not contain any whitespace for purposes other than separating arguments, as the different platforms deal 258 * with whitespace in different and incompatible ways. 259 * <p> 260 * @implNote Example:<ul> 261 * <li>Shebang line in {@code script.js}: {@code #!/path/to/jjs --language=es6}</li> 262 * <li>Command line: {@code ./script.js arg2}</li> 263 * <li>{@code args} array passed to Nashorn: {@code --language=es6,./script.js,arg}</li> 264 * <li>Required canonicalized arguments array: {@code --language=es6,./script.js,--,arg2}</li> 265 * </ul> 266 * 267 * @param args the command line arguments as passed into Nashorn. 268 * @return the passed and possibly canonicalized argument list 269 */ 270 private static String[] preprocessArgs(final String[] args) { 271 if (args.length == 0) { 272 return args; 273 } 274 275 final List<String> processedArgs = new ArrayList<>(); 276 processedArgs.addAll(Arrays.asList(args)); 277 278 // Nashorn supports passing multiple shebang arguments. On platforms that pass anything following the 279 // shebang interpreter notice as one argument, the first element of the argument array needs to be special-cased 280 // as it might actually contain several arguments. Mac OS X splits shebang arguments, other platforms don't. 281 // This special handling is also only necessary if the first argument actually starts with an option. 282 if (args[0].startsWith("-") && !System.getProperty("os.name", "generic").startsWith("Mac OS X")) { 283 processedArgs.addAll(0, tokenizeString(processedArgs.remove(0))); 284 } 285 286 int shebangFilePos = -1; // -1 signifies "none found" 287 // identify a shebang file and its position in the arguments array (if any) 288 for (int i = 0; i < processedArgs.size(); ++i) { 289 final String a = processedArgs.get(i); 290 if (!a.startsWith("-")) { 291 final Path p = Paths.get(a); 292 String l = ""; 293 try (final BufferedReader r = Files.newBufferedReader(p)) { 294 l = r.readLine(); 295 } catch (IOException ioe) { 296 // ignore 297 } 298 if (l.startsWith("#!")) { 299 shebangFilePos = i; 300 } 301 // We're only checking the first non-option argument. If it's not a shebang file, we're in normal 302 // execution mode. 303 break; 304 } 305 } 306 if (shebangFilePos != -1) { 307 // Insert the argument separator after the shebang script file. 308 processedArgs.add(shebangFilePos + 1, "--"); 309 } 310 return processedArgs.stream().toArray(String[]::new); 311 } 312 313 public static List<String> tokenizeString(final String str) { 314 final StreamTokenizer tokenizer = new StreamTokenizer(new StringReader(str)); 315 tokenizer.resetSyntax(); 316 tokenizer.wordChars(0, 255); 317 tokenizer.whitespaceChars(0, ' '); 318 tokenizer.commentChar('#'); 319 tokenizer.quoteChar('"'); 320 tokenizer.quoteChar('\''); 321 final List<String> tokenList = new ArrayList<>(); 322 final StringBuilder toAppend = new StringBuilder(); 323 while (nextToken(tokenizer) != StreamTokenizer.TT_EOF) { 324 final String s = tokenizer.sval; 325 // The tokenizer understands about honoring quoted strings and recognizes 326 // them as one token that possibly contains multiple space-separated words. 327 // It does not recognize quoted spaces, though, and will split after the 328 // escaping \ character. This is handled here. 329 if (s.endsWith("\\")) { 330 // omit trailing \, append space instead 331 toAppend.append(s.substring(0, s.length() - 1)).append(' '); 332 } else { 333 tokenList.add(toAppend.append(s).toString()); 334 toAppend.setLength(0); 335 } 336 } 337 if (toAppend.length() != 0) { 338 tokenList.add(toAppend.toString()); 339 } 340 return tokenList; 341 } 342 343 private static int nextToken(final StreamTokenizer tokenizer) { 344 try { 345 return tokenizer.nextToken(); 346 } catch (final IOException ioe) { 347 return StreamTokenizer.TT_EOF; 348 } 349 } 350 351 /** 352 * Compiles the given script files in the command line 353 * This is called only when using the --compile-only flag 354 * 355 * @param context the nashorn context 356 * @param global the global scope 357 * @param files the list of script files to compile 358 * 359 * @return error code 360 * @throws IOException when any script file read results in I/O error 361 */ 362 private static int compileScripts(final Context context, final Global global, final List<String> files) throws IOException { 363 final Global oldGlobal = Context.getGlobal(); 364 final boolean globalChanged = (oldGlobal != global); 365 final ScriptEnvironment env = context.getEnv(); 366 try { 367 if (globalChanged) { 368 Context.setGlobal(global); 369 } 370 final ErrorManager errors = context.getErrorManager(); 371 372 // For each file on the command line. 373 for (final String fileName : files) { 374 final FunctionNode functionNode = new Parser(env, sourceFor(fileName, new File(fileName)), errors, env._strict, 0, context.getLogger(Parser.class)).parse(); 375 376 if (errors.getNumberOfErrors() != 0) { 377 return COMPILATION_ERROR; 378 } 379 380 Compiler.forNoInstallerCompilation( 381 context, 382 functionNode.getSource(), 383 env._strict | functionNode.isStrict()). 384 compile(functionNode, CompilationPhases.COMPILE_ALL_NO_INSTALL); 385 386 if (env._print_ast) { 387 context.getErr().println(new ASTWriter(functionNode)); 388 } 389 390 if (env._print_parse) { 391 context.getErr().println(new PrintVisitor(functionNode)); 392 } 393 394 if (errors.getNumberOfErrors() != 0) { 395 return COMPILATION_ERROR; 396 } 397 } 398 } finally { 399 env.getOut().flush(); 400 env.getErr().flush(); 401 if (globalChanged) { 402 Context.setGlobal(oldGlobal); 403 } 404 } 405 406 return SUCCESS; 407 } 408 409 /** 410 * Runs the given JavaScript files in the command line 411 * 412 * @param context the nashorn context 413 * @param global the global scope 414 * @param files the list of script files to run 415 * 416 * @return error code 417 * @throws IOException when any script file read results in I/O error 418 */ 419 private int runScripts(final Context context, final Global global, final List<String> files) throws IOException { 420 final Global oldGlobal = Context.getGlobal(); 421 final boolean globalChanged = (oldGlobal != global); 422 try { 423 if (globalChanged) { 424 Context.setGlobal(global); 425 } 426 final ErrorManager errors = context.getErrorManager(); 427 428 // For each file on the command line. 429 for (final String fileName : files) { 430 if ("-".equals(fileName)) { 431 final int res = readEvalPrint(context, global); 432 if (res != SUCCESS) { 433 return res; 434 } 435 continue; 436 } 437 438 final File file = new File(fileName); 439 final ScriptFunction script = context.compileScript(sourceFor(fileName, file), global); 440 if (script == null || errors.getNumberOfErrors() != 0) { 441 return COMPILATION_ERROR; 442 } 443 444 try { 445 apply(script, global); 446 } catch (final NashornException e) { 447 errors.error(e.toString()); 448 if (context.getEnv()._dump_on_error) { 449 e.printStackTrace(context.getErr()); 450 } 451 452 return RUNTIME_ERROR; 453 } 454 } 455 } finally { 456 context.getOut().flush(); 457 context.getErr().flush(); 458 if (globalChanged) { 459 Context.setGlobal(oldGlobal); 460 } 461 } 462 463 return SUCCESS; 464 } 465 466 /** 467 * Runs launches "fx:bootstrap.js" with the given JavaScript files provided 468 * as arguments. 469 * 470 * @param context the nashorn context 471 * @param global the global scope 472 * @param files the list of script files to provide 473 * 474 * @return error code 475 * @throws IOException when any script file read results in I/O error 476 */ 477 private static int runFXScripts(final Context context, final Global global, final List<String> files) throws IOException { 478 final Global oldGlobal = Context.getGlobal(); 479 final boolean globalChanged = (oldGlobal != global); 480 try { 481 if (globalChanged) { 482 Context.setGlobal(global); 483 } 484 485 global.addOwnProperty("$GLOBAL", Property.NOT_ENUMERABLE, global); 486 global.addOwnProperty("$SCRIPTS", Property.NOT_ENUMERABLE, files); 487 context.load(global, "fx:bootstrap.js"); 488 } catch (final NashornException e) { 489 context.getErrorManager().error(e.toString()); 490 if (context.getEnv()._dump_on_error) { 491 e.printStackTrace(context.getErr()); 492 } 493 494 return RUNTIME_ERROR; 495 } finally { 496 context.getOut().flush(); 497 context.getErr().flush(); 498 if (globalChanged) { 499 Context.setGlobal(oldGlobal); 500 } 501 } 502 503 return SUCCESS; 504 } 505 506 /** 507 * Hook to ScriptFunction "apply". A performance metering shell may 508 * introduce enter/exit timing here. 509 * 510 * @param target target function for apply 511 * @param self self reference for apply 512 * 513 * @return result of the function apply 514 */ 515 protected Object apply(final ScriptFunction target, final Object self) { 516 return ScriptRuntime.apply(target, self); 517 } 518 519 /** 520 * Parse potentially partial code and keep track of the start of last expression. 521 * This 'partial' parsing support is meant to be used for code-completion. 522 * 523 * @param context the nashorn context 524 * @param code code that is to be parsed 525 * @return the start index of the last expression parsed in the (incomplete) code. 526 */ 527 @Override 528 public final int getLastExpressionStart(final Context context, final String code) { 529 final int[] exprStart = { -1 }; 530 531 final Parser p = new Parser(context.getEnv(), sourceFor("<partial_code>", code),new Context.ThrowErrorManager()) { 532 @Override 533 protected Expression expression() { 534 exprStart[0] = this.start; 535 return super.expression(); 536 } 537 538 @Override 539 protected Expression assignmentExpression(final boolean noIn) { 540 exprStart[0] = this.start; 541 return super.expression(); 542 } 543 }; 544 545 try { 546 p.parse(); 547 } catch (final Exception ignored) { 548 // throw any parser exception, but we are partial parsing anyway 549 } 550 551 return exprStart[0]; 552 } 553 554 555 /** 556 * read-eval-print loop for Nashorn shell. 557 * 558 * @param context the nashorn context 559 * @param global global scope object to use 560 * @return return code 561 */ 562 protected int readEvalPrint(final Context context, final Global global) { 563 final String prompt = bundle.getString("shell.prompt"); 564 final BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); 565 final PrintWriter err = context.getErr(); 566 final Global oldGlobal = Context.getGlobal(); 567 final boolean globalChanged = (oldGlobal != global); 568 final ScriptEnvironment env = context.getEnv(); 569 570 try { 571 if (globalChanged) { 572 Context.setGlobal(global); 573 } 574 575 global.addShellBuiltins(); 576 577 while (true) { 578 err.print(prompt); 579 err.flush(); 580 581 String source = ""; 582 try { 583 source = in.readLine(); 584 } catch (final IOException ioe) { 585 err.println(ioe.toString()); 586 } 587 588 if (source == null) { 589 break; 590 } 591 592 if (source.isEmpty()) { 593 continue; 594 } 595 596 try { 597 final Object res = context.eval(global, source, global, "<shell>"); 598 if (res != ScriptRuntime.UNDEFINED) { 599 err.println(toString(res, global)); 600 } 601 } catch (final Exception e) { 602 err.println(e); 603 if (env._dump_on_error) { 604 e.printStackTrace(err); 605 } 606 } 607 } 608 } finally { 609 if (globalChanged) { 610 Context.setGlobal(oldGlobal); 611 } 612 } 613 614 return SUCCESS; 615 } 616 617 /** 618 * Converts {@code result} to a printable string. The reason we don't use {@link JSType#toString(Object)} 619 * or {@link ScriptRuntime#safeToString(Object)} is that we want to be able to render Symbol values 620 * even if they occur within an Array, and therefore have to implement our own Array to String 621 * conversion. 622 * 623 * @param result the result 624 * @param global the global object 625 * @return the string representation 626 */ 627 protected static String toString(final Object result, final Global global) { 628 if (result instanceof Symbol) { 629 // Normal implicit conversion of symbol to string would throw TypeError 630 return result.toString(); 631 } 632 633 if (result instanceof NativeSymbol) { 634 return JSType.toPrimitive(result).toString(); 635 } 636 637 if (isArrayWithDefaultToString(result, global)) { 638 // This should yield the same string as Array.prototype.toString but 639 // will not throw if the array contents include symbols. 640 final StringBuilder sb = new StringBuilder(); 641 final Iterator<Object> iter = ArrayLikeIterator.arrayLikeIterator(result, true); 642 643 while (iter.hasNext()) { 644 final Object obj = iter.next(); 645 646 if (obj != null && obj != ScriptRuntime.UNDEFINED) { 647 sb.append(toString(obj, global)); 648 } 649 650 if (iter.hasNext()) { 651 sb.append(','); 652 } 653 } 654 655 return sb.toString(); 656 } 657 658 return JSType.toString(result); 659 } 660 661 private static boolean isArrayWithDefaultToString(final Object result, final Global global) { 662 if (result instanceof ScriptObject) { 663 final ScriptObject sobj = (ScriptObject) result; 664 return sobj.isArray() && sobj.get("toString") == global.getArrayPrototype().get("toString"); 665 } 666 return false; 667 } 668} 669