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-rw-r--r--trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/JavaScriptCompressor.java1307
1 files changed, 1307 insertions, 0 deletions
diff --git a/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/JavaScriptCompressor.java b/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/JavaScriptCompressor.java
new file mode 100644
index 0000000..e69ae1a
--- /dev/null
+++ b/trunk/infrastructure/yuicompressor/src/com/yahoo/platform/yui/compressor/JavaScriptCompressor.java
@@ -0,0 +1,1307 @@
+/*
+ * YUI Compressor
+ * Author: Julien Lecomte <jlecomte@yahoo-inc.com>
+ * Copyright (c) 2007, Yahoo! Inc. All rights reserved.
+ * Code licensed under the BSD License:
+ * http://developer.yahoo.net/yui/license.txt
+ */
+
+package com.yahoo.platform.yui.compressor;
+
+import yuicompressor.org.mozilla.javascript.*;
+
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
+import java.util.*;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class JavaScriptCompressor {
+
+ static final ArrayList ones;
+ static final ArrayList twos;
+ static final ArrayList threes;
+
+ static final Set builtin = new HashSet();
+ static final Map literals = new Hashtable();
+ static final Set reserved = new HashSet();
+
+ static {
+
+ // This list contains all the 3 characters or less built-in global
+ // symbols available in a browser. Please add to this list if you
+ // see anything missing.
+ builtin.add("NaN");
+ builtin.add("top");
+
+ ones = new ArrayList();
+ for (char c = 'A'; c <= 'Z'; c++)
+ ones.add(Character.toString(c));
+ for (char c = 'a'; c <= 'z'; c++)
+ ones.add(Character.toString(c));
+
+ twos = new ArrayList();
+ for (int i = 0; i < ones.size(); i++) {
+ String one = (String) ones.get(i);
+ for (char c = 'A'; c <= 'Z'; c++)
+ twos.add(one + Character.toString(c));
+ for (char c = 'a'; c <= 'z'; c++)
+ twos.add(one + Character.toString(c));
+ for (char c = '0'; c <= '9'; c++)
+ twos.add(one + Character.toString(c));
+ }
+
+ // Remove two-letter JavaScript reserved words and built-in globals...
+ twos.remove("as");
+ twos.remove("is");
+ twos.remove("do");
+ twos.remove("if");
+ twos.remove("in");
+ twos.removeAll(builtin);
+
+ threes = new ArrayList();
+ for (int i = 0; i < twos.size(); i++) {
+ String two = (String) twos.get(i);
+ for (char c = 'A'; c <= 'Z'; c++)
+ threes.add(two + Character.toString(c));
+ for (char c = 'a'; c <= 'z'; c++)
+ threes.add(two + Character.toString(c));
+ for (char c = '0'; c <= '9'; c++)
+ threes.add(two + Character.toString(c));
+ }
+
+ // Remove three-letter JavaScript reserved words and built-in globals...
+ threes.remove("for");
+ threes.remove("int");
+ threes.remove("new");
+ threes.remove("try");
+ threes.remove("use");
+ threes.remove("var");
+ threes.removeAll(builtin);
+
+ // That's up to ((26+26)*(1+(26+26+10)))*(1+(26+26+10))-8
+ // (206,380 symbols per scope)
+
+ // The following list comes from org/mozilla/javascript/Decompiler.java...
+ literals.put(new Integer(Token.GET), "get ");
+ literals.put(new Integer(Token.SET), "set ");
+ literals.put(new Integer(Token.TRUE), "true");
+ literals.put(new Integer(Token.FALSE), "false");
+ literals.put(new Integer(Token.NULL), "null");
+ literals.put(new Integer(Token.THIS), "this");
+ literals.put(new Integer(Token.FUNCTION), "function");
+ literals.put(new Integer(Token.COMMA), ",");
+ literals.put(new Integer(Token.LC), "{");
+ literals.put(new Integer(Token.RC), "}");
+ literals.put(new Integer(Token.LP), "(");
+ literals.put(new Integer(Token.RP), ")");
+ literals.put(new Integer(Token.LB), "[");
+ literals.put(new Integer(Token.RB), "]");
+ literals.put(new Integer(Token.DOT), ".");
+ literals.put(new Integer(Token.NEW), "new ");
+ literals.put(new Integer(Token.DELPROP), "delete ");
+ literals.put(new Integer(Token.IF), "if");
+ literals.put(new Integer(Token.ELSE), "else");
+ literals.put(new Integer(Token.FOR), "for");
+ literals.put(new Integer(Token.IN), " in ");
+ literals.put(new Integer(Token.WITH), "with");
+ literals.put(new Integer(Token.WHILE), "while");
+ literals.put(new Integer(Token.DO), "do");
+ literals.put(new Integer(Token.TRY), "try");
+ literals.put(new Integer(Token.CATCH), "catch");
+ literals.put(new Integer(Token.FINALLY), "finally");
+ literals.put(new Integer(Token.THROW), "throw");
+ literals.put(new Integer(Token.SWITCH), "switch");
+ literals.put(new Integer(Token.BREAK), "break");
+ literals.put(new Integer(Token.CONTINUE), "continue");
+ literals.put(new Integer(Token.CASE), "case");
+ literals.put(new Integer(Token.DEFAULT), "default");
+ literals.put(new Integer(Token.RETURN), "return");
+ literals.put(new Integer(Token.VAR), "var ");
+ literals.put(new Integer(Token.SEMI), ";");
+ literals.put(new Integer(Token.ASSIGN), "=");
+ literals.put(new Integer(Token.ASSIGN_ADD), "+=");
+ literals.put(new Integer(Token.ASSIGN_SUB), "-=");
+ literals.put(new Integer(Token.ASSIGN_MUL), "*=");
+ literals.put(new Integer(Token.ASSIGN_DIV), "/=");
+ literals.put(new Integer(Token.ASSIGN_MOD), "%=");
+ literals.put(new Integer(Token.ASSIGN_BITOR), "|=");
+ literals.put(new Integer(Token.ASSIGN_BITXOR), "^=");
+ literals.put(new Integer(Token.ASSIGN_BITAND), "&=");
+ literals.put(new Integer(Token.ASSIGN_LSH), "<<=");
+ literals.put(new Integer(Token.ASSIGN_RSH), ">>=");
+ literals.put(new Integer(Token.ASSIGN_URSH), ">>>=");
+ literals.put(new Integer(Token.HOOK), "?");
+ literals.put(new Integer(Token.OBJECTLIT), ":");
+ literals.put(new Integer(Token.COLON), ":");
+ literals.put(new Integer(Token.OR), "||");
+ literals.put(new Integer(Token.AND), "&&");
+ literals.put(new Integer(Token.BITOR), "|");
+ literals.put(new Integer(Token.BITXOR), "^");
+ literals.put(new Integer(Token.BITAND), "&");
+ literals.put(new Integer(Token.SHEQ), "===");
+ literals.put(new Integer(Token.SHNE), "!==");
+ literals.put(new Integer(Token.EQ), "==");
+ literals.put(new Integer(Token.NE), "!=");
+ literals.put(new Integer(Token.LE), "<=");
+ literals.put(new Integer(Token.LT), "<");
+ literals.put(new Integer(Token.GE), ">=");
+ literals.put(new Integer(Token.GT), ">");
+ literals.put(new Integer(Token.INSTANCEOF), " instanceof ");
+ literals.put(new Integer(Token.LSH), "<<");
+ literals.put(new Integer(Token.RSH), ">>");
+ literals.put(new Integer(Token.URSH), ">>>");
+ literals.put(new Integer(Token.TYPEOF), "typeof");
+ literals.put(new Integer(Token.VOID), "void ");
+ literals.put(new Integer(Token.CONST), "const ");
+ literals.put(new Integer(Token.NOT), "!");
+ literals.put(new Integer(Token.BITNOT), "~");
+ literals.put(new Integer(Token.POS), "+");
+ literals.put(new Integer(Token.NEG), "-");
+ literals.put(new Integer(Token.INC), "++");
+ literals.put(new Integer(Token.DEC), "--");
+ literals.put(new Integer(Token.ADD), "+");
+ literals.put(new Integer(Token.SUB), "-");
+ literals.put(new Integer(Token.MUL), "*");
+ literals.put(new Integer(Token.DIV), "/");
+ literals.put(new Integer(Token.MOD), "%");
+ literals.put(new Integer(Token.COLONCOLON), "::");
+ literals.put(new Integer(Token.DOTDOT), "..");
+ literals.put(new Integer(Token.DOTQUERY), ".(");
+ literals.put(new Integer(Token.XMLATTR), "@");
+
+ // See http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Reserved_Words
+
+ // JavaScript 1.5 reserved words
+ reserved.add("break");
+ reserved.add("case");
+ reserved.add("catch");
+ reserved.add("continue");
+ reserved.add("default");
+ reserved.add("delete");
+ reserved.add("do");
+ reserved.add("else");
+ reserved.add("finally");
+ reserved.add("for");
+ reserved.add("function");
+ reserved.add("if");
+ reserved.add("in");
+ reserved.add("instanceof");
+ reserved.add("new");
+ reserved.add("return");
+ reserved.add("switch");
+ reserved.add("this");
+ reserved.add("throw");
+ reserved.add("try");
+ reserved.add("typeof");
+ reserved.add("var");
+ reserved.add("void");
+ reserved.add("while");
+ reserved.add("with");
+ // Words reserved for future use
+ reserved.add("abstract");
+ reserved.add("boolean");
+ reserved.add("byte");
+ reserved.add("char");
+ reserved.add("class");
+ reserved.add("const");
+ reserved.add("debugger");
+ reserved.add("double");
+ reserved.add("enum");
+ reserved.add("export");
+ reserved.add("extends");
+ reserved.add("final");
+ reserved.add("float");
+ reserved.add("goto");
+ reserved.add("implements");
+ reserved.add("import");
+ reserved.add("int");
+ reserved.add("interface");
+ reserved.add("long");
+ reserved.add("native");
+ reserved.add("package");
+ reserved.add("private");
+ reserved.add("protected");
+ reserved.add("public");
+ reserved.add("short");
+ reserved.add("static");
+ reserved.add("super");
+ reserved.add("synchronized");
+ reserved.add("throws");
+ reserved.add("transient");
+ reserved.add("volatile");
+ // These are not reserved, but should be taken into account
+ // in isValidIdentifier (See jslint source code)
+ reserved.add("arguments");
+ reserved.add("eval");
+ reserved.add("true");
+ reserved.add("false");
+ reserved.add("Infinity");
+ reserved.add("NaN");
+ reserved.add("null");
+ reserved.add("undefined");
+ }
+
+ private static int countChar(String haystack, char needle) {
+ int idx = 0;
+ int count = 0;
+ int length = haystack.length();
+ while (idx < length) {
+ char c = haystack.charAt(idx++);
+ if (c == needle) {
+ count++;
+ }
+ }
+ return count;
+ }
+
+ private static int printSourceString(String source, int offset, StringBuffer sb) {
+ int length = source.charAt(offset);
+ ++offset;
+ if ((0x8000 & length) != 0) {
+ length = ((0x7FFF & length) << 16) | source.charAt(offset);
+ ++offset;
+ }
+ if (sb != null) {
+ String str = source.substring(offset, offset + length);
+ sb.append(str);
+ }
+ return offset + length;
+ }
+
+ private static int printSourceNumber(String source,
+ int offset, StringBuffer sb) {
+ double number = 0.0;
+ char type = source.charAt(offset);
+ ++offset;
+ if (type == 'S') {
+ if (sb != null) {
+ number = source.charAt(offset);
+ }
+ ++offset;
+ } else if (type == 'J' || type == 'D') {
+ if (sb != null) {
+ long lbits;
+ lbits = (long) source.charAt(offset) << 48;
+ lbits |= (long) source.charAt(offset + 1) << 32;
+ lbits |= (long) source.charAt(offset + 2) << 16;
+ lbits |= (long) source.charAt(offset + 3);
+ if (type == 'J') {
+ number = lbits;
+ } else {
+ number = Double.longBitsToDouble(lbits);
+ }
+ }
+ offset += 4;
+ } else {
+ // Bad source
+ throw new RuntimeException();
+ }
+ if (sb != null) {
+ sb.append(ScriptRuntime.numberToString(number, 10));
+ }
+ return offset;
+ }
+
+ private static ArrayList parse(Reader in, ErrorReporter reporter)
+ throws IOException, EvaluatorException {
+
+ CompilerEnvirons env = new CompilerEnvirons();
+ Parser parser = new Parser(env, reporter);
+ parser.parse(in, null, 1);
+ String source = parser.getEncodedSource();
+
+ int offset = 0;
+ int length = source.length();
+ ArrayList tokens = new ArrayList();
+ StringBuffer sb = new StringBuffer();
+
+ while (offset < length) {
+ int tt = source.charAt(offset++);
+ switch (tt) {
+
+ case Token.SPECIALCOMMENT:
+ case Token.NAME:
+ case Token.REGEXP:
+ case Token.STRING:
+ sb.setLength(0);
+ offset = printSourceString(source, offset, sb);
+ tokens.add(new JavaScriptToken(tt, sb.toString()));
+ break;
+
+ case Token.NUMBER:
+ sb.setLength(0);
+ offset = printSourceNumber(source, offset, sb);
+ tokens.add(new JavaScriptToken(tt, sb.toString()));
+ break;
+
+ default:
+ String literal = (String) literals.get(new Integer(tt));
+ if (literal != null) {
+ tokens.add(new JavaScriptToken(tt, literal));
+ }
+ break;
+ }
+ }
+
+ return tokens;
+ }
+
+ private static void processStringLiterals(ArrayList tokens, boolean merge) {
+
+ String tv;
+ int i, length = tokens.size();
+ JavaScriptToken token, prevToken, nextToken;
+
+ if (merge) {
+
+ // Concatenate string literals that are being appended wherever
+ // it is safe to do so. Note that we take care of the case:
+ // "a" + "b".toUpperCase()
+
+ for (i = 0; i < length; i++) {
+ token = (JavaScriptToken) tokens.get(i);
+ switch (token.getType()) {
+
+ case Token.ADD:
+ if (i > 0 && i < length) {
+ prevToken = (JavaScriptToken) tokens.get(i - 1);
+ nextToken = (JavaScriptToken) tokens.get(i + 1);
+ if (prevToken.getType() == Token.STRING && nextToken.getType() == Token.STRING &&
+ (i == length - 1 || ((JavaScriptToken) tokens.get(i + 2)).getType() != Token.DOT)) {
+ tokens.set(i - 1, new JavaScriptToken(Token.STRING,
+ prevToken.getValue() + nextToken.getValue()));
+ tokens.remove(i + 1);
+ tokens.remove(i);
+ i = i - 1;
+ length = length - 2;
+ break;
+ }
+ }
+ }
+ }
+
+ }
+
+ // Second pass...
+
+ for (i = 0; i < length; i++) {
+ // APPJET modifications in this loop
+ token = (JavaScriptToken) tokens.get(i);
+ if (token.getType() == Token.STRING || token.getType() == Token.REGEXP) {
+ tv = token.getValue();
+ if (token.getType() == Token.STRING) {
+
+ // Finally, add the quoting characters and escape the string. We use
+ // the quoting character that minimizes the amount of escaping to save
+ // a few additional bytes.
+
+ char quotechar;
+ int singleQuoteCount = countChar(tv, '\'');
+ int doubleQuoteCount = countChar(tv, '"');
+ if (doubleQuoteCount <= singleQuoteCount) {
+ quotechar = '"';
+ } else {
+ quotechar = '\'';
+ }
+
+ tv = quotechar + escapeString(tv, quotechar) + quotechar;
+ }
+
+ // String concatenation transforms the old script scheme:
+ // '<scr'+'ipt ...><'+'/script>'
+ // into the following:
+ // '<script ...></script>'
+ // which breaks if this code is embedded inside an HTML document.
+ // Since this is not the right way to do this, let's fix the code by
+ // transforming all "</script" into "<\/script"
+
+ // (Anti-malware software can be sensitive to open tags)
+ tv = tv.replace("<script", "\\x3cscript");
+ tv = tv.replace("</script", "\\x3c/script");
+
+ tokens.set(i, new JavaScriptToken(token.getType(), tv));
+ }
+ }
+ }
+
+ // Add necessary escaping that was removed in Rhino's tokenizer.
+ private static String escapeString(String s, char quotechar) {
+
+ assert quotechar == '"' || quotechar == '\'';
+
+ if (s == null) {
+ return null;
+ }
+
+ StringBuffer sb = new StringBuffer();
+ for (int i = 0, L = s.length(); i < L; i++) {
+ int c = s.charAt(i);
+ if (c == quotechar) {
+ sb.append("\\");
+ }
+ sb.append((char) c);
+ }
+
+ return sb.toString();
+ }
+
+ /*
+ * Simple check to see whether a string is a valid identifier name.
+ * If a string matches this pattern, it means it IS a valid
+ * identifier name. If a string doesn't match it, it does not
+ * necessarily mean it is not a valid identifier name.
+ */
+ private static final Pattern SIMPLE_IDENTIFIER_NAME_PATTERN = Pattern.compile("^[a-zA-Z_][a-zA-Z0-9_]*$");
+
+ private static boolean isValidIdentifier(String s) {
+ Matcher m = SIMPLE_IDENTIFIER_NAME_PATTERN.matcher(s);
+ return (m.matches() && !reserved.contains(s));
+ }
+
+ /*
+ * Transforms obj["foo"] into obj.foo whenever possible, saving 3 bytes.
+ */
+ private static void optimizeObjectMemberAccess(ArrayList tokens) {
+
+ String tv;
+ int i, length;
+ JavaScriptToken token;
+
+ for (i = 0, length = tokens.size(); i < length; i++) {
+
+ if (((JavaScriptToken) tokens.get(i)).getType() == Token.LB &&
+ i > 0 && i < length - 2 &&
+ ((JavaScriptToken) tokens.get(i - 1)).getType() == Token.NAME &&
+ ((JavaScriptToken) tokens.get(i + 1)).getType() == Token.STRING &&
+ ((JavaScriptToken) tokens.get(i + 2)).getType() == Token.RB) {
+ token = (JavaScriptToken) tokens.get(i + 1);
+ tv = token.getValue();
+ tv = tv.substring(1, tv.length() - 1);
+ if (isValidIdentifier(tv)) {
+ tokens.set(i, new JavaScriptToken(Token.DOT, "."));
+ tokens.set(i + 1, new JavaScriptToken(Token.NAME, tv));
+ tokens.remove(i + 2);
+ i = i + 2;
+ length = length - 1;
+ }
+ }
+ }
+ }
+
+ /*
+ * Transforms 'foo': ... into foo: ... whenever possible, saving 2 bytes.
+ */
+ private static void optimizeObjLitMemberDecl(ArrayList tokens) {
+
+ String tv;
+ int i, length;
+ JavaScriptToken token;
+
+ for (i = 0, length = tokens.size(); i < length; i++) {
+ if (((JavaScriptToken) tokens.get(i)).getType() == Token.OBJECTLIT &&
+ i > 0 && ((JavaScriptToken) tokens.get(i - 1)).getType() == Token.STRING) {
+ token = (JavaScriptToken) tokens.get(i - 1);
+ tv = token.getValue();
+ tv = tv.substring(1, tv.length() - 1);
+ if (isValidIdentifier(tv)) {
+ tokens.set(i - 1, new JavaScriptToken(Token.NAME, tv));
+ }
+ }
+ }
+ }
+
+ private ErrorReporter logger;
+
+ private boolean munge;
+ private boolean verbose;
+
+ private static final int BUILDING_SYMBOL_TREE = 1;
+ private static final int CHECKING_SYMBOL_TREE = 2;
+
+ private int mode;
+ private int offset;
+ private int braceNesting;
+ private ArrayList tokens;
+ private Stack scopes = new Stack();
+ private ScriptOrFnScope globalScope = new ScriptOrFnScope(-1, null);
+ private Hashtable indexedScopes = new Hashtable();
+
+ public JavaScriptCompressor(Reader in, ErrorReporter reporter)
+ throws IOException, EvaluatorException {
+
+ this.logger = reporter;
+ this.tokens = parse(in, reporter);
+ }
+
+ public void compress(Writer out, int linebreak, boolean munge, boolean verbose,
+ boolean preserveAllSemiColons, boolean disableOptimizations)
+ throws IOException {
+
+ this.munge = munge;
+ this.verbose = verbose;
+
+ processStringLiterals(this.tokens, !disableOptimizations);
+
+ if (!disableOptimizations) {
+ optimizeObjectMemberAccess(this.tokens);
+ optimizeObjLitMemberDecl(this.tokens);
+ }
+
+ buildSymbolTree();
+ // DO NOT TOUCH this.tokens BETWEEN THESE TWO PHASES (BECAUSE OF this.indexedScopes)
+ mungeSymboltree();
+ StringBuffer sb = printSymbolTree(linebreak, preserveAllSemiColons);
+
+ out.write(sb.toString());
+ }
+
+ private ScriptOrFnScope getCurrentScope() {
+ return (ScriptOrFnScope) scopes.peek();
+ }
+
+ private void enterScope(ScriptOrFnScope scope) {
+ scopes.push(scope);
+ }
+
+ private void leaveCurrentScope() {
+ scopes.pop();
+ }
+
+ private JavaScriptToken consumeToken() {
+ return (JavaScriptToken) tokens.get(offset++);
+ }
+
+ private JavaScriptToken getToken(int delta) {
+ return (JavaScriptToken) tokens.get(offset + delta);
+ }
+
+ /*
+ * Returns the identifier for the specified symbol defined in
+ * the specified scope or in any scope above it. Returns null
+ * if this symbol does not have a corresponding identifier.
+ */
+ private JavaScriptIdentifier getIdentifier(String symbol, ScriptOrFnScope scope) {
+ JavaScriptIdentifier identifier;
+ while (scope != null) {
+ identifier = scope.getIdentifier(symbol);
+ if (identifier != null) {
+ return identifier;
+ }
+ scope = scope.getParentScope();
+ }
+ return null;
+ }
+
+ /*
+ * If either 'eval' or 'with' is used in a local scope, we must make
+ * sure that all containing local scopes don't get munged. Otherwise,
+ * the obfuscation would potentially introduce bugs.
+ */
+ private void protectScopeFromObfuscation(ScriptOrFnScope scope) {
+ assert scope != null;
+
+ if (scope == globalScope) {
+ // The global scope does not get obfuscated,
+ // so we don't need to worry about it...
+ return;
+ }
+
+ // Find the highest local scope containing the specified scope.
+ while (scope.getParentScope() != globalScope) {
+ scope = scope.getParentScope();
+ }
+
+ assert scope.getParentScope() == globalScope;
+ scope.preventMunging();
+ }
+
+ private String getDebugString(int max) {
+ assert max > 0;
+ StringBuffer result = new StringBuffer();
+ int start = Math.max(offset - max, 0);
+ int end = Math.min(offset + max, tokens.size());
+ for (int i = start; i < end; i++) {
+ JavaScriptToken token = (JavaScriptToken) tokens.get(i);
+ if (i == offset - 1) {
+ result.append(" ---> ");
+ }
+ result.append(token.getValue());
+ if (i == offset - 1) {
+ result.append(" <--- ");
+ }
+ }
+ return result.toString();
+ }
+
+ private void warn(String message, boolean showDebugString) {
+ if (verbose) {
+ if (showDebugString) {
+ message = message + "\n" + getDebugString(10);
+ }
+ logger.warning(message, null, -1, null, -1);
+ }
+ }
+
+ private void parseFunctionDeclaration() {
+
+ String symbol;
+ JavaScriptToken token;
+ ScriptOrFnScope currentScope, fnScope;
+ JavaScriptIdentifier identifier;
+
+ currentScope = getCurrentScope();
+
+ token = consumeToken();
+ if (token.getType() == Token.NAME) {
+ if (mode == BUILDING_SYMBOL_TREE) {
+ // Get the name of the function and declare it in the current scope.
+ symbol = token.getValue();
+ if (currentScope.getIdentifier(symbol) != null) {
+ warn("The function " + symbol + " has already been declared in the same scope...", true);
+ }
+ currentScope.declareIdentifier(symbol);
+ }
+ token = consumeToken();
+ }
+
+ assert token.getType() == Token.LP;
+ if (mode == BUILDING_SYMBOL_TREE) {
+ fnScope = new ScriptOrFnScope(braceNesting, currentScope);
+ indexedScopes.put(new Integer(offset), fnScope);
+ } else {
+ fnScope = (ScriptOrFnScope) indexedScopes.get(new Integer(offset));
+ }
+
+ // Parse function arguments.
+ int argpos = 0;
+ while ((token = consumeToken()).getType() != Token.RP) {
+ assert token.getType() == Token.NAME ||
+ token.getType() == Token.COMMA;
+ if (token.getType() == Token.NAME && mode == BUILDING_SYMBOL_TREE) {
+ symbol = token.getValue();
+ identifier = fnScope.declareIdentifier(symbol);
+ if (symbol.equals("$super") && argpos == 0) {
+ // Exception for Prototype 1.6...
+ identifier.preventMunging();
+ }
+ argpos++;
+ }
+ }
+
+ token = consumeToken();
+ assert token.getType() == Token.LC;
+ braceNesting++;
+
+ token = getToken(0);
+ if (token.getType() == Token.STRING &&
+ getToken(1).getType() == Token.SEMI) {
+ // This is a hint. Hints are empty statements that look like
+ // "localvar1:nomunge, localvar2:nomunge"; They allow developers
+ // to prevent specific symbols from getting obfuscated (some heretic
+ // implementations, such as Prototype 1.6, require specific variable
+ // names, such as $super for example, in order to work appropriately.
+ // Note: right now, only "nomunge" is supported in the right hand side
+ // of a hint. However, in the future, the right hand side may contain
+ // other values.
+ consumeToken();
+ String hints = token.getValue();
+ // Remove the leading and trailing quotes...
+ hints = hints.substring(1, hints.length() - 1).trim();
+ StringTokenizer st1 = new StringTokenizer(hints, ",");
+ while (st1.hasMoreTokens()) {
+ String hint = st1.nextToken();
+ int idx = hint.indexOf(':');
+ if (idx <= 0 || idx >= hint.length() - 1) {
+ if (mode == BUILDING_SYMBOL_TREE) {
+ // No need to report the error twice, hence the test...
+ warn("Invalid hint syntax: " + hint, true);
+ }
+ break;
+ }
+ String variableName = hint.substring(0, idx).trim();
+ String variableType = hint.substring(idx + 1).trim();
+ if (mode == BUILDING_SYMBOL_TREE) {
+ fnScope.addHint(variableName, variableType);
+ } else if (mode == CHECKING_SYMBOL_TREE) {
+ identifier = fnScope.getIdentifier(variableName);
+ if (identifier != null) {
+ if (variableType.equals("nomunge")) {
+ identifier.preventMunging();
+ } else {
+ warn("Unsupported hint value: " + hint, true);
+ }
+ } else {
+ warn("Hint refers to an unknown identifier: " + hint, true);
+ }
+ }
+ }
+ }
+
+ parseScope(fnScope);
+ }
+
+ private void parseCatch() {
+
+ String symbol;
+ JavaScriptToken token;
+ ScriptOrFnScope currentScope;
+ JavaScriptIdentifier identifier;
+
+ token = getToken(-1);
+ assert token.getType() == Token.CATCH;
+ token = consumeToken();
+ assert token.getType() == Token.LP;
+ token = consumeToken();
+ assert token.getType() == Token.NAME;
+
+ symbol = token.getValue();
+ currentScope = getCurrentScope();
+
+ if (mode == BUILDING_SYMBOL_TREE) {
+ // We must declare the exception identifier in the containing function
+ // scope to avoid errors related to the obfuscation process. No need to
+ // display a warning if the symbol was already declared here...
+ currentScope.declareIdentifier(symbol);
+ } else {
+ identifier = getIdentifier(symbol, currentScope);
+ identifier.incrementRefcount();
+ }
+
+ token = consumeToken();
+ assert token.getType() == Token.RP;
+ }
+
+ private void parseExpression() {
+
+ // Parse the expression until we encounter a comma or a semi-colon
+ // in the same brace nesting, bracket nesting and paren nesting.
+ // Parse functions if any...
+
+ String symbol;
+ JavaScriptToken token;
+ ScriptOrFnScope currentScope;
+ JavaScriptIdentifier identifier;
+
+ int expressionBraceNesting = braceNesting;
+ int bracketNesting = 0;
+ int parensNesting = 0;
+
+ int length = tokens.size();
+
+ while (offset < length) {
+
+ token = consumeToken();
+ currentScope = getCurrentScope();
+
+ switch (token.getType()) {
+
+ case Token.SEMI:
+ case Token.COMMA:
+ if (braceNesting == expressionBraceNesting &&
+ bracketNesting == 0 &&
+ parensNesting == 0) {
+ return;
+ }
+ break;
+
+ case Token.FUNCTION:
+ parseFunctionDeclaration();
+ break;
+
+ case Token.LC:
+ braceNesting++;
+ break;
+
+ case Token.RC:
+ braceNesting--;
+ assert braceNesting >= expressionBraceNesting;
+ break;
+
+ case Token.LB:
+ bracketNesting++;
+ break;
+
+ case Token.RB:
+ bracketNesting--;
+ break;
+
+ case Token.LP:
+ parensNesting++;
+ break;
+
+ case Token.RP:
+ parensNesting--;
+ break;
+
+ case Token.SPECIALCOMMENT:
+ if (mode == BUILDING_SYMBOL_TREE) {
+ protectScopeFromObfuscation(currentScope);
+ warn("Using JScript conditional comments is not recommended." + (munge ? " Moreover, using JScript conditional comments reduces the level of compression!" : ""), true);
+ }
+ break;
+
+ case Token.NAME:
+ symbol = token.getValue();
+
+ if (mode == BUILDING_SYMBOL_TREE) {
+
+ if (symbol.equals("eval")) {
+
+ protectScopeFromObfuscation(currentScope);
+ warn("Using 'eval' is not recommended." + (munge ? " Moreover, using 'eval' reduces the level of compression!" : ""), true);
+
+ }
+
+ } else if (mode == CHECKING_SYMBOL_TREE) {
+
+ if ((offset < 2 ||
+ (getToken(-2).getType() != Token.DOT &&
+ getToken(-2).getType() != Token.GET &&
+ getToken(-2).getType() != Token.SET)) &&
+ getToken(0).getType() != Token.OBJECTLIT) {
+
+ identifier = getIdentifier(symbol, currentScope);
+
+ if (identifier == null) {
+
+ if (symbol.length() <= 3 && !builtin.contains(symbol)) {
+ // Here, we found an undeclared and un-namespaced symbol that is
+ // 3 characters or less in length. Declare it in the global scope.
+ // We don't need to declare longer symbols since they won't cause
+ // any conflict with other munged symbols.
+ globalScope.declareIdentifier(symbol);
+ warn("Found an undeclared symbol: " + symbol, true);
+ }
+
+ } else {
+
+ identifier.incrementRefcount();
+ }
+ }
+ }
+ break;
+ }
+ }
+ }
+
+ private void parseScope(ScriptOrFnScope scope) {
+
+ String symbol;
+ JavaScriptToken token;
+ JavaScriptIdentifier identifier;
+
+ int length = tokens.size();
+
+ enterScope(scope);
+
+ while (offset < length) {
+
+ token = consumeToken();
+
+ switch (token.getType()) {
+
+ case Token.VAR:
+
+ if (mode == BUILDING_SYMBOL_TREE && scope.incrementVarCount() > 1) {
+ warn("Try to use a single 'var' statement per scope.", true);
+ }
+
+ /* FALLSTHROUGH */
+
+ case Token.CONST:
+
+ // The var keyword is followed by at least one symbol name.
+ // If several symbols follow, they are comma separated.
+ for (; ;) {
+ token = consumeToken();
+
+ assert token.getType() == Token.NAME;
+
+ if (mode == BUILDING_SYMBOL_TREE) {
+ symbol = token.getValue();
+ if (scope.getIdentifier(symbol) == null) {
+ scope.declareIdentifier(symbol);
+ } else {
+ warn("The variable " + symbol + " has already been declared in the same scope...", true);
+ }
+ }
+
+ token = getToken(0);
+
+ assert token.getType() == Token.SEMI ||
+ token.getType() == Token.ASSIGN ||
+ token.getType() == Token.COMMA ||
+ token.getType() == Token.IN;
+
+ if (token.getType() == Token.IN) {
+ break;
+ } else {
+ parseExpression();
+ token = getToken(-1);
+ if (token.getType() == Token.SEMI) {
+ break;
+ }
+ }
+ }
+ break;
+
+ case Token.FUNCTION:
+ parseFunctionDeclaration();
+ break;
+
+ case Token.LC:
+ braceNesting++;
+ break;
+
+ case Token.RC:
+ braceNesting--;
+ assert braceNesting >= scope.getBraceNesting();
+ if (braceNesting == scope.getBraceNesting()) {
+ leaveCurrentScope();
+ return;
+ }
+ break;
+
+ case Token.WITH:
+ if (mode == BUILDING_SYMBOL_TREE) {
+ // Inside a 'with' block, it is impossible to figure out
+ // statically whether a symbol is a local variable or an
+ // object member. As a consequence, the only thing we can
+ // do is turn the obfuscation off for the highest scope
+ // containing the 'with' block.
+ protectScopeFromObfuscation(scope);
+ warn("Using 'with' is not recommended." + (munge ? " Moreover, using 'with' reduces the level of compression!" : ""), true);
+ }
+ break;
+
+ case Token.CATCH:
+ parseCatch();
+ break;
+
+ case Token.SPECIALCOMMENT:
+ if (mode == BUILDING_SYMBOL_TREE) {
+ protectScopeFromObfuscation(scope);
+ warn("Using JScript conditional comments is not recommended." + (munge ? " Moreover, using JScript conditional comments reduces the level of compression." : ""), true);
+ }
+ break;
+
+ case Token.NAME:
+ symbol = token.getValue();
+
+ if (mode == BUILDING_SYMBOL_TREE) {
+
+ if (symbol.equals("eval")) {
+
+ protectScopeFromObfuscation(scope);
+ warn("Using 'eval' is not recommended." + (munge ? " Moreover, using 'eval' reduces the level of compression!" : ""), true);
+
+ }
+
+ } else if (mode == CHECKING_SYMBOL_TREE) {
+
+ if ((offset < 2 || getToken(-2).getType() != Token.DOT) &&
+ getToken(0).getType() != Token.OBJECTLIT) {
+
+ identifier = getIdentifier(symbol, scope);
+
+ if (identifier == null) {
+
+ if (symbol.length() <= 3 && !builtin.contains(symbol)) {
+ // Here, we found an undeclared and un-namespaced symbol that is
+ // 3 characters or less in length. Declare it in the global scope.
+ // We don't need to declare longer symbols since they won't cause
+ // any conflict with other munged symbols.
+ globalScope.declareIdentifier(symbol);
+ warn("Found an undeclared symbol: " + symbol, true);
+ }
+
+ } else {
+
+ identifier.incrementRefcount();
+ }
+ }
+ }
+ break;
+ }
+ }
+ }
+
+ private void buildSymbolTree() {
+ offset = 0;
+ braceNesting = 0;
+ scopes.clear();
+ indexedScopes.clear();
+ indexedScopes.put(new Integer(0), globalScope);
+ mode = BUILDING_SYMBOL_TREE;
+ parseScope(globalScope);
+ }
+
+ private void mungeSymboltree() {
+
+ if (!munge) {
+ return;
+ }
+
+ // One problem with obfuscation resides in the use of undeclared
+ // and un-namespaced global symbols that are 3 characters or less
+ // in length. Here is an example:
+ //
+ // var declaredGlobalVar;
+ //
+ // function declaredGlobalFn() {
+ // var localvar;
+ // localvar = abc; // abc is an undeclared global symbol
+ // }
+ //
+ // In the example above, there is a slim chance that localvar may be
+ // munged to 'abc', conflicting with the undeclared global symbol
+ // abc, creating a potential bug. The following code detects such
+ // global symbols. This must be done AFTER the entire file has been
+ // parsed, and BEFORE munging the symbol tree. Note that declaring
+ // extra symbols in the global scope won't hurt.
+ //
+ // Note: Since we go through all the tokens to do this, we also use
+ // the opportunity to count how many times each identifier is used.
+
+ offset = 0;
+ braceNesting = 0;
+ scopes.clear();
+ mode = CHECKING_SYMBOL_TREE;
+ parseScope(globalScope);
+ globalScope.munge();
+ }
+
+ private StringBuffer printSymbolTree(int linebreakpos, boolean preserveAllSemiColons)
+ throws IOException {
+
+ offset = 0;
+ braceNesting = 0;
+ scopes.clear();
+
+ String symbol;
+ JavaScriptToken token;
+ ScriptOrFnScope currentScope;
+ JavaScriptIdentifier identifier;
+
+ int length = tokens.size();
+ StringBuffer result = new StringBuffer();
+
+ int linestartpos = 0;
+
+ enterScope(globalScope);
+
+ while (offset < length) {
+
+ token = consumeToken();
+ symbol = token.getValue();
+ currentScope = getCurrentScope();
+
+ switch (token.getType()) {
+
+ case Token.NAME:
+
+ if (offset >= 2 && getToken(-2).getType() == Token.DOT ||
+ getToken(0).getType() == Token.OBJECTLIT) {
+
+ result.append(symbol);
+
+ } else {
+
+ identifier = getIdentifier(symbol, currentScope);
+ if (identifier != null) {
+ if (identifier.getMungedValue() != null) {
+ result.append(identifier.getMungedValue());
+ } else {
+ result.append(symbol);
+ }
+ if (currentScope != globalScope && identifier.getRefcount() == 0) {
+ warn("The symbol " + symbol + " is declared but is apparently never used.\nThis code can probably be written in a more compact way.", true);
+ }
+ } else {
+ result.append(symbol);
+ }
+ }
+ break;
+
+ case Token.REGEXP:
+ case Token.NUMBER:
+ case Token.STRING:
+ result.append(symbol);
+ break;
+
+ case Token.ADD:
+ case Token.SUB:
+ result.append((String) literals.get(new Integer(token.getType())));
+ if (offset < length) {
+ token = getToken(0);
+ if (token.getType() == Token.INC ||
+ token.getType() == Token.DEC ||
+ token.getType() == Token.ADD ||
+ token.getType() == Token.DEC) {
+ // Handle the case x +/- ++/-- y
+ // We must keep a white space here. Otherwise, x +++ y would be
+ // interpreted as x ++ + y by the compiler, which is a bug (due
+ // to the implicit assignment being done on the wrong variable)
+ result.append(' ');
+ } else if (token.getType() == Token.POS && getToken(-1).getType() == Token.ADD ||
+ token.getType() == Token.NEG && getToken(-1).getType() == Token.SUB) {
+ // Handle the case x + + y and x - - y
+ result.append(' ');
+ }
+ }
+ break;
+
+ case Token.FUNCTION:
+ result.append("function");
+ token = consumeToken();
+ if (token.getType() == Token.NAME) {
+ result.append(' ');
+ symbol = token.getValue();
+ identifier = getIdentifier(symbol, currentScope);
+ assert identifier != null;
+ if (identifier.getMungedValue() != null) {
+ result.append(identifier.getMungedValue());
+ } else {
+ result.append(symbol);
+ }
+ if (currentScope != globalScope && identifier.getRefcount() == 0) {
+ warn("The symbol " + symbol + " is declared but is apparently never used.\nThis code can probably be written in a more compact way.", true);
+ }
+ token = consumeToken();
+ }
+ assert token.getType() == Token.LP;
+ result.append('(');
+ currentScope = (ScriptOrFnScope) indexedScopes.get(new Integer(offset));
+ enterScope(currentScope);
+ while ((token = consumeToken()).getType() != Token.RP) {
+ assert token.getType() == Token.NAME || token.getType() == Token.COMMA;
+ if (token.getType() == Token.NAME) {
+ symbol = token.getValue();
+ identifier = getIdentifier(symbol, currentScope);
+ assert identifier != null;
+ if (identifier.getMungedValue() != null) {
+ result.append(identifier.getMungedValue());
+ } else {
+ result.append(symbol);
+ }
+ } else if (token.getType() == Token.COMMA) {
+ result.append(',');
+ }
+ }
+ result.append(')');
+ token = consumeToken();
+ assert token.getType() == Token.LC;
+ result.append('{');
+ braceNesting++;
+ token = getToken(0);
+ if (token.getType() == Token.STRING &&
+ getToken(1).getType() == Token.SEMI) {
+ // This is a hint. Skip it!
+ consumeToken();
+ consumeToken();
+ }
+ break;
+
+ case Token.RETURN:
+ case Token.TYPEOF:
+ result.append(literals.get(new Integer(token.getType())));
+ // No space needed after 'return' and 'typeof' when followed
+ // by '(', '[', '{', a string or a regexp.
+ if (offset < length) {
+ token = getToken(0);
+ if (token.getType() != Token.LP &&
+ token.getType() != Token.LB &&
+ token.getType() != Token.LC &&
+ token.getType() != Token.STRING &&
+ token.getType() != Token.REGEXP &&
+ token.getType() != Token.SEMI) {
+ result.append(' ');
+ }
+ }
+ break;
+
+ case Token.CASE:
+ case Token.THROW:
+ result.append(literals.get(new Integer(token.getType())));
+ // White-space needed after 'case' and 'throw' when not followed by a string.
+ if (offset < length && getToken(0).getType() != Token.STRING) {
+ result.append(' ');
+ }
+ break;
+
+ case Token.BREAK:
+ case Token.CONTINUE:
+ result.append(literals.get(new Integer(token.getType())));
+ if (offset < length && getToken(0).getType() != Token.SEMI) {
+ // If 'break' or 'continue' is not followed by a semi-colon, it must
+ // be followed by a label, hence the need for a white space.
+ result.append(' ');
+ }
+ break;
+
+ case Token.LC:
+ result.append('{');
+ braceNesting++;
+ break;
+
+ case Token.RC:
+ result.append('}');
+ braceNesting--;
+ assert braceNesting >= currentScope.getBraceNesting();
+ if (braceNesting == currentScope.getBraceNesting()) {
+ leaveCurrentScope();
+ }
+ break;
+
+ case Token.SEMI:
+ // No need to output a semi-colon if the next character is a right-curly...
+ if (preserveAllSemiColons || offset < length && getToken(0).getType() != Token.RC) {
+ result.append(';');
+ }
+
+ if (linebreakpos >= 0 && result.length() - linestartpos > linebreakpos) {
+ // Some source control tools don't like it when files containing lines longer
+ // than, say 8000 characters, are checked in. The linebreak option is used in
+ // that case to split long lines after a specific column.
+ result.append('\n');
+ linestartpos = result.length();
+ }
+ break;
+
+ case Token.SPECIALCOMMENT:
+ if (result.length() > 0 && result.charAt(result.length() - 1) != '\n') {
+ result.append("\n");
+ }
+ result.append("/*");
+ result.append(symbol);
+ result.append("*/\n");
+ break;
+
+ default:
+ String literal = (String) literals.get(new Integer(token.getType()));
+ if (literal != null) {
+ result.append(literal);
+ } else {
+ warn("This symbol cannot be printed: " + symbol, true);
+ }
+ break;
+ }
+ }
+
+ // Append a semi-colon at the end, even if unnecessary semi-colons are
+ // supposed to be removed. This is especially useful when concatenating
+ // several minified files (the absence of an ending semi-colon at the
+ // end of one file may very likely cause a syntax error)
+ if (!preserveAllSemiColons && result.length() > 0) {
+ if (result.charAt(result.length() - 1) == '\n') {
+ result.setCharAt(result.length() - 1, ';');
+ } else {
+ result.append(';');
+ }
+ }
+
+ return result;
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 13:09:05 +0000