michael@0: /*
michael@0:  * Copyright (c) 2007 Henri Sivonen
michael@0:  * Copyright (c) 2008-2010 Mozilla Foundation
michael@0:  *
michael@0:  * Permission is hereby granted, free of charge, to any person obtaining a 
michael@0:  * copy of this software and associated documentation files (the "Software"), 
michael@0:  * to deal in the Software without restriction, including without limitation 
michael@0:  * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
michael@0:  * and/or sell copies of the Software, and to permit persons to whom the 
michael@0:  * Software is furnished to do so, subject to the following conditions:
michael@0:  *
michael@0:  * The above copyright notice and this permission notice shall be included in 
michael@0:  * all copies or substantial portions of the Software.
michael@0:  *
michael@0:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
michael@0:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
michael@0:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
michael@0:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
michael@0:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
michael@0:  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
michael@0:  * DEALINGS IN THE SOFTWARE.
michael@0:  */
michael@0: 
michael@0: package nu.validator.htmlparser.impl;
michael@0: 
michael@0: import java.io.IOException;
michael@0: 
michael@0: import nu.validator.htmlparser.annotation.Auto;
michael@0: import nu.validator.htmlparser.annotation.Inline;
michael@0: import nu.validator.htmlparser.common.ByteReadable;
michael@0: 
michael@0: import org.xml.sax.SAXException;
michael@0: 
michael@0: public abstract class MetaScanner {
michael@0: 
michael@0:     /**
michael@0:      * Constant for "charset".
michael@0:      */
michael@0:     private static final char[] CHARSET = { 'h', 'a', 'r', 's', 'e', 't' };
michael@0:     
michael@0:     /**
michael@0:      * Constant for "content".
michael@0:      */
michael@0:     private static final char[] CONTENT = { 'o', 'n', 't', 'e', 'n', 't' };
michael@0: 
michael@0:     /**
michael@0:      * Constant for "http-equiv".
michael@0:      */
michael@0:     private static final char[] HTTP_EQUIV = { 't', 't', 'p', '-', 'e', 'q',
michael@0:             'u', 'i', 'v' };
michael@0: 
michael@0:     /**
michael@0:      * Constant for "content-type".
michael@0:      */
michael@0:     private static final char[] CONTENT_TYPE = { 'c', 'o', 'n', 't', 'e', 'n',
michael@0:             't', '-', 't', 'y', 'p', 'e' };
michael@0: 
michael@0:     private static final int NO = 0;
michael@0: 
michael@0:     private static final int M = 1;
michael@0:     
michael@0:     private static final int E = 2;
michael@0:     
michael@0:     private static final int T = 3;
michael@0: 
michael@0:     private static final int A = 4;
michael@0:     
michael@0:     private static final int DATA = 0;
michael@0: 
michael@0:     private static final int TAG_OPEN = 1;
michael@0: 
michael@0:     private static final int SCAN_UNTIL_GT = 2;
michael@0: 
michael@0:     private static final int TAG_NAME = 3;
michael@0: 
michael@0:     private static final int BEFORE_ATTRIBUTE_NAME = 4;
michael@0: 
michael@0:     private static final int ATTRIBUTE_NAME = 5;
michael@0: 
michael@0:     private static final int AFTER_ATTRIBUTE_NAME = 6;
michael@0: 
michael@0:     private static final int BEFORE_ATTRIBUTE_VALUE = 7;
michael@0: 
michael@0:     private static final int ATTRIBUTE_VALUE_DOUBLE_QUOTED = 8;
michael@0: 
michael@0:     private static final int ATTRIBUTE_VALUE_SINGLE_QUOTED = 9;
michael@0: 
michael@0:     private static final int ATTRIBUTE_VALUE_UNQUOTED = 10;
michael@0: 
michael@0:     private static final int AFTER_ATTRIBUTE_VALUE_QUOTED = 11;
michael@0: 
michael@0:     private static final int MARKUP_DECLARATION_OPEN = 13;
michael@0:     
michael@0:     private static final int MARKUP_DECLARATION_HYPHEN = 14;
michael@0: 
michael@0:     private static final int COMMENT_START = 15;
michael@0: 
michael@0:     private static final int COMMENT_START_DASH = 16;
michael@0: 
michael@0:     private static final int COMMENT = 17;
michael@0: 
michael@0:     private static final int COMMENT_END_DASH = 18;
michael@0: 
michael@0:     private static final int COMMENT_END = 19;
michael@0:     
michael@0:     private static final int SELF_CLOSING_START_TAG = 20;
michael@0:     
michael@0:     private static final int HTTP_EQUIV_NOT_SEEN = 0;
michael@0:     
michael@0:     private static final int HTTP_EQUIV_CONTENT_TYPE = 1;
michael@0: 
michael@0:     private static final int HTTP_EQUIV_OTHER = 2;
michael@0: 
michael@0:     /**
michael@0:      * The data source.
michael@0:      */
michael@0:     protected ByteReadable readable;
michael@0:     
michael@0:     /**
michael@0:      * The state of the state machine that recognizes the tag name "meta".
michael@0:      */
michael@0:     private int metaState = NO;
michael@0: 
michael@0:     /**
michael@0:      * The current position in recognizing the attribute name "content".
michael@0:      */
michael@0:     private int contentIndex = Integer.MAX_VALUE;
michael@0:     
michael@0:     /**
michael@0:      * The current position in recognizing the attribute name "charset".
michael@0:      */
michael@0:     private int charsetIndex = Integer.MAX_VALUE;
michael@0: 
michael@0:     /**
michael@0:      * The current position in recognizing the attribute name "http-equive".
michael@0:      */
michael@0:     private int httpEquivIndex = Integer.MAX_VALUE;
michael@0: 
michael@0:     /**
michael@0:      * The current position in recognizing the attribute value "content-type".
michael@0:      */
michael@0:     private int contentTypeIndex = Integer.MAX_VALUE;
michael@0: 
michael@0:     /**
michael@0:      * The tokenizer state.
michael@0:      */
michael@0:     protected int stateSave = DATA;
michael@0: 
michael@0:     /**
michael@0:      * The currently filled length of strBuf.
michael@0:      */
michael@0:     private int strBufLen;
michael@0: 
michael@0:     /**
michael@0:      * Accumulation buffer for attribute values.
michael@0:      */
michael@0:     private @Auto char[] strBuf;
michael@0:     
michael@0:     private String content;
michael@0:     
michael@0:     private String charset;
michael@0:     
michael@0:     private int httpEquivState;
michael@0:     
michael@0:     public MetaScanner() {
michael@0:         this.readable = null;
michael@0:         this.metaState = NO;
michael@0:         this.contentIndex = Integer.MAX_VALUE;
michael@0:         this.charsetIndex = Integer.MAX_VALUE;
michael@0:         this.httpEquivIndex = Integer.MAX_VALUE;
michael@0:         this.contentTypeIndex = Integer.MAX_VALUE;
michael@0:         this.stateSave = DATA;
michael@0:         this.strBufLen = 0;
michael@0:         this.strBuf = new char[36];
michael@0:         this.content = null;
michael@0:         this.charset = null;
michael@0:         this.httpEquivState = HTTP_EQUIV_NOT_SEEN;
michael@0:     }
michael@0:     
michael@0:     @SuppressWarnings("unused") private void destructor() {
michael@0:         Portability.releaseString(content);
michael@0:         Portability.releaseString(charset);
michael@0:     }
michael@0: 
michael@0:     // [NOCPP[
michael@0:     
michael@0:     /**
michael@0:      * Reads a byte from the data source.
michael@0:      * 
michael@0:      * -1 means end.
michael@0:      * @return
michael@0:      * @throws IOException
michael@0:      */
michael@0:     protected int read() throws IOException {
michael@0:         return readable.readByte();
michael@0:     }
michael@0: 
michael@0:     // ]NOCPP]
michael@0: 
michael@0:     // WARNING When editing this, makes sure the bytecode length shown by javap
michael@0:     // stays under 8000 bytes!
michael@0:     /**
michael@0:      * The runs the meta scanning algorithm.
michael@0:      */
michael@0:     protected final void stateLoop(int state)
michael@0:             throws SAXException, IOException {
michael@0:         int c = -1;
michael@0:         boolean reconsume = false;
michael@0:         stateloop: for (;;) {
michael@0:             switch (state) {
michael@0:                 case DATA:
michael@0:                     dataloop: for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '<':
michael@0:                                 state = MetaScanner.TAG_OPEN;
michael@0:                                 break dataloop; // FALL THROUGH continue
michael@0:                             // stateloop;
michael@0:                             default:
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // WARNING FALLTHRU CASE TRANSITION: DON'T REORDER
michael@0:                 case TAG_OPEN:
michael@0:                     tagopenloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case 'm':
michael@0:                             case 'M':
michael@0:                                 metaState = M;
michael@0:                                 state = MetaScanner.TAG_NAME;
michael@0:                                 break tagopenloop;
michael@0:                                 // continue stateloop;                                
michael@0:                             case '!':
michael@0:                                 state = MetaScanner.MARKUP_DECLARATION_OPEN;
michael@0:                                 continue stateloop;
michael@0:                             case '?':
michael@0:                             case '/':
michael@0:                                 state = MetaScanner.SCAN_UNTIL_GT;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z')) {
michael@0:                                     metaState = NO;
michael@0:                                     state = MetaScanner.TAG_NAME;
michael@0:                                     break tagopenloop;
michael@0:                                     // continue stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 reconsume = true;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALL THROUGH DON'T REORDER
michael@0:                 case TAG_NAME:
michael@0:                     tagnameloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_NAME;
michael@0:                                 break tagnameloop;
michael@0:                             // continue stateloop;
michael@0:                             case '/':
michael@0:                                 state = MetaScanner.SELF_CLOSING_START_TAG;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             case 'e':
michael@0:                             case 'E':
michael@0:                                 if (metaState == M) {
michael@0:                                     metaState = E;
michael@0:                                 } else {
michael@0:                                     metaState = NO;
michael@0:                                 }
michael@0:                                 continue;
michael@0:                             case 't':
michael@0:                             case 'T':
michael@0:                                 if (metaState == E) {
michael@0:                                     metaState = T;
michael@0:                                 } else {
michael@0:                                     metaState = NO;
michael@0:                                 }
michael@0:                                 continue;
michael@0:                             case 'a':
michael@0:                             case 'A':
michael@0:                                 if (metaState == T) {
michael@0:                                     metaState = A;
michael@0:                                 } else {
michael@0:                                     metaState = NO;
michael@0:                                 }
michael@0:                                 continue;
michael@0:                             default:
michael@0:                                 metaState = NO;
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case BEFORE_ATTRIBUTE_NAME:
michael@0:                     beforeattributenameloop: for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         /*
michael@0:                          * Consume the next input character:
michael@0:                          */
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 continue;
michael@0:                             case '/':
michael@0:                                 state = MetaScanner.SELF_CLOSING_START_TAG;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = DATA;
michael@0:                                 continue stateloop;
michael@0:                             case 'c':
michael@0:                             case 'C':
michael@0:                                 contentIndex = 0;
michael@0:                                 charsetIndex = 0;
michael@0:                                 httpEquivIndex = Integer.MAX_VALUE;
michael@0:                                 contentTypeIndex = Integer.MAX_VALUE;
michael@0:                                 state = MetaScanner.ATTRIBUTE_NAME;
michael@0:                                 break beforeattributenameloop;                                
michael@0:                             case 'h':
michael@0:                             case 'H':
michael@0:                                 contentIndex = Integer.MAX_VALUE;
michael@0:                                 charsetIndex = Integer.MAX_VALUE;
michael@0:                                 httpEquivIndex = 0;
michael@0:                                 contentTypeIndex = Integer.MAX_VALUE;
michael@0:                                 state = MetaScanner.ATTRIBUTE_NAME;
michael@0:                                 break beforeattributenameloop;                                
michael@0:                             default:
michael@0:                                 contentIndex = Integer.MAX_VALUE;
michael@0:                                 charsetIndex = Integer.MAX_VALUE;
michael@0:                                 httpEquivIndex = Integer.MAX_VALUE;
michael@0:                                 contentTypeIndex = Integer.MAX_VALUE;
michael@0:                                 state = MetaScanner.ATTRIBUTE_NAME;
michael@0:                                 break beforeattributenameloop;
michael@0:                             // continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case ATTRIBUTE_NAME:
michael@0:                     attributenameloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 state = MetaScanner.AFTER_ATTRIBUTE_NAME;
michael@0:                                 continue stateloop;
michael@0:                             case '/':
michael@0:                                 state = MetaScanner.SELF_CLOSING_START_TAG;
michael@0:                                 continue stateloop;
michael@0:                             case '=':
michael@0:                                 strBufLen = 0;
michael@0:                                 contentTypeIndex = 0;
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_VALUE;
michael@0:                                 break attributenameloop;
michael@0:                             // continue stateloop;
michael@0:                             case '>':
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 if (metaState == A) {
michael@0:                                     if (c >= 'A' && c <= 'Z') {
michael@0:                                         c += 0x20;
michael@0:                                     }
michael@0:                                     if (contentIndex < CONTENT.length && c == CONTENT[contentIndex]) {
michael@0:                                         ++contentIndex;
michael@0:                                     } else {
michael@0:                                         contentIndex = Integer.MAX_VALUE;
michael@0:                                     }
michael@0:                                     if (charsetIndex < CHARSET.length && c == CHARSET[charsetIndex]) {
michael@0:                                         ++charsetIndex;
michael@0:                                     } else {
michael@0:                                         charsetIndex = Integer.MAX_VALUE;
michael@0:                                     }
michael@0:                                     if (httpEquivIndex < HTTP_EQUIV.length && c == HTTP_EQUIV[httpEquivIndex]) {
michael@0:                                         ++httpEquivIndex;
michael@0:                                     } else {
michael@0:                                         httpEquivIndex = Integer.MAX_VALUE;
michael@0:                                     }                                    
michael@0:                                 }
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case BEFORE_ATTRIBUTE_VALUE:
michael@0:                     beforeattributevalueloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 continue;
michael@0:                             case '"':
michael@0:                                 state = MetaScanner.ATTRIBUTE_VALUE_DOUBLE_QUOTED;
michael@0:                                 break beforeattributevalueloop;
michael@0:                             // continue stateloop;
michael@0:                             case '\'':
michael@0:                                 state = MetaScanner.ATTRIBUTE_VALUE_SINGLE_QUOTED;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 handleCharInAttributeValue(c);
michael@0:                                 state = MetaScanner.ATTRIBUTE_VALUE_UNQUOTED;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case ATTRIBUTE_VALUE_DOUBLE_QUOTED:
michael@0:                     attributevaluedoublequotedloop: for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '"':
michael@0:                                 handleAttributeValue();
michael@0:                                 state = MetaScanner.AFTER_ATTRIBUTE_VALUE_QUOTED;
michael@0:                                 break attributevaluedoublequotedloop;
michael@0:                             // continue stateloop;
michael@0:                             default:
michael@0:                                 handleCharInAttributeValue(c);
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case AFTER_ATTRIBUTE_VALUE_QUOTED:
michael@0:                     afterattributevaluequotedloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_NAME;
michael@0:                                 continue stateloop;
michael@0:                             case '/':
michael@0:                                 state = MetaScanner.SELF_CLOSING_START_TAG;
michael@0:                                 break afterattributevaluequotedloop;
michael@0:                             // continue stateloop;
michael@0:                             case '>':
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_NAME;
michael@0:                                 reconsume = true;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case SELF_CLOSING_START_TAG:
michael@0:                     c = read();
michael@0:                     switch (c) {
michael@0:                         case -1:
michael@0:                             break stateloop;
michael@0:                         case '>':
michael@0:                             if (handleTag()) {
michael@0:                                 break stateloop;
michael@0:                             }
michael@0:                             state = MetaScanner.DATA;
michael@0:                             continue stateloop;
michael@0:                         default:
michael@0:                             state = MetaScanner.BEFORE_ATTRIBUTE_NAME;
michael@0:                             reconsume = true;
michael@0:                             continue stateloop;
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case ATTRIBUTE_VALUE_UNQUOTED:
michael@0:                     for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0: 
michael@0:                             case '\u000C':
michael@0:                                 handleAttributeValue();
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_NAME;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 handleAttributeValue();
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 handleCharInAttributeValue(c);
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case AFTER_ATTRIBUTE_NAME:
michael@0:                     for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case ' ':
michael@0:                             case '\t':
michael@0:                             case '\n':
michael@0:                             case '\u000C':
michael@0:                                 continue;
michael@0:                             case '/':
michael@0:                                 handleAttributeValue();
michael@0:                                 state = MetaScanner.SELF_CLOSING_START_TAG;
michael@0:                                 continue stateloop;
michael@0:                             case '=':
michael@0:                                 strBufLen = 0;
michael@0:                                 contentTypeIndex = 0;
michael@0:                                 state = MetaScanner.BEFORE_ATTRIBUTE_VALUE;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 handleAttributeValue();
michael@0:                                 if (handleTag()) {
michael@0:                                     break stateloop;
michael@0:                                 }
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             case 'c':
michael@0:                             case 'C':
michael@0:                                 contentIndex = 0;
michael@0:                                 charsetIndex = 0;
michael@0:                                 state = MetaScanner.ATTRIBUTE_NAME;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 contentIndex = Integer.MAX_VALUE;
michael@0:                                 charsetIndex = Integer.MAX_VALUE;
michael@0:                                 state = MetaScanner.ATTRIBUTE_NAME;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case MARKUP_DECLARATION_OPEN:
michael@0:                     markupdeclarationopenloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '-':
michael@0:                                 state = MetaScanner.MARKUP_DECLARATION_HYPHEN;
michael@0:                                 break markupdeclarationopenloop;
michael@0:                             // continue stateloop;
michael@0:                             default:
michael@0:                                 state = MetaScanner.SCAN_UNTIL_GT;
michael@0:                                 reconsume = true;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case MARKUP_DECLARATION_HYPHEN:
michael@0:                     markupdeclarationhyphenloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '-':
michael@0:                                 state = MetaScanner.COMMENT_START;
michael@0:                                 break markupdeclarationhyphenloop;
michael@0:                             // continue stateloop;
michael@0:                             default:
michael@0:                                 state = MetaScanner.SCAN_UNTIL_GT;
michael@0:                                 reconsume = true;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case COMMENT_START:
michael@0:                     commentstartloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '-':
michael@0:                                 state = MetaScanner.COMMENT_START_DASH;
michael@0:                                 continue stateloop;
michael@0:                             case '>':
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 state = MetaScanner.COMMENT;
michael@0:                                 break commentstartloop;
michael@0:                             // continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case COMMENT:
michael@0:                     commentloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '-':
michael@0:                                 state = MetaScanner.COMMENT_END_DASH;
michael@0:                                 break commentloop;
michael@0:                             // continue stateloop;
michael@0:                             default:
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case COMMENT_END_DASH:
michael@0:                     commentenddashloop: for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '-':
michael@0:                                 state = MetaScanner.COMMENT_END;
michael@0:                                 break commentenddashloop;
michael@0:                             // continue stateloop;
michael@0:                             default:
michael@0:                                 state = MetaScanner.COMMENT;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // FALLTHRU DON'T REORDER
michael@0:                 case COMMENT_END:
michael@0:                     for (;;) {
michael@0:                         c = read();
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '>':
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             case '-':
michael@0:                                 continue;
michael@0:                             default:
michael@0:                                 state = MetaScanner.COMMENT;
michael@0:                                 continue stateloop;
michael@0:                         }
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case COMMENT_START_DASH:
michael@0:                     c = read();
michael@0:                     switch (c) {
michael@0:                         case -1:
michael@0:                             break stateloop;
michael@0:                         case '-':
michael@0:                             state = MetaScanner.COMMENT_END;
michael@0:                             continue stateloop;
michael@0:                         case '>':
michael@0:                             state = MetaScanner.DATA;
michael@0:                             continue stateloop;
michael@0:                         default:
michael@0:                             state = MetaScanner.COMMENT;
michael@0:                             continue stateloop;
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case ATTRIBUTE_VALUE_SINGLE_QUOTED:
michael@0:                     for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '\'':
michael@0:                                 handleAttributeValue();
michael@0:                                 state = MetaScanner.AFTER_ATTRIBUTE_VALUE_QUOTED;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 handleCharInAttributeValue(c);
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:                     // XXX reorder point
michael@0:                 case SCAN_UNTIL_GT:
michael@0:                     for (;;) {
michael@0:                         if (reconsume) {
michael@0:                             reconsume = false;
michael@0:                         } else {
michael@0:                             c = read();
michael@0:                         }
michael@0:                         switch (c) {
michael@0:                             case -1:
michael@0:                                 break stateloop;
michael@0:                             case '>':
michael@0:                                 state = MetaScanner.DATA;
michael@0:                                 continue stateloop;
michael@0:                             default:
michael@0:                                 continue;
michael@0:                         }
michael@0:                     }
michael@0:             }
michael@0:         }
michael@0:         stateSave  = state;
michael@0:     }
michael@0: 
michael@0:     private void handleCharInAttributeValue(int c) {
michael@0:         if (metaState == A) {
michael@0:             if (contentIndex == CONTENT.length || charsetIndex == CHARSET.length) {
michael@0:                 addToBuffer(c);
michael@0:             } else if (httpEquivIndex == HTTP_EQUIV.length) {
michael@0:                 if (contentTypeIndex < CONTENT_TYPE.length && toAsciiLowerCase(c) == CONTENT_TYPE[contentTypeIndex]) {
michael@0:                     ++contentTypeIndex;
michael@0:                 } else {
michael@0:                     contentTypeIndex = Integer.MAX_VALUE;
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Inline private int toAsciiLowerCase(int c) {
michael@0:         if (c >= 'A' && c <= 'Z') {
michael@0:             return c + 0x20;
michael@0:         }
michael@0:         return c;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Adds a character to the accumulation buffer.
michael@0:      * @param c the character to add
michael@0:      */
michael@0:     private void addToBuffer(int c) {
michael@0:         if (strBufLen == strBuf.length) {
michael@0:             char[] newBuf = new char[strBuf.length + (strBuf.length << 1)];
michael@0:             System.arraycopy(strBuf, 0, newBuf, 0, strBuf.length);
michael@0:             strBuf = newBuf;
michael@0:         }
michael@0:         strBuf[strBufLen++] = (char)c;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Attempts to extract a charset name from the accumulation buffer.
michael@0:      * @return <code>true</code> if successful
michael@0:      * @throws SAXException
michael@0:      */
michael@0:     private void handleAttributeValue() throws SAXException {
michael@0:         if (metaState != A) {
michael@0:             return;
michael@0:         }
michael@0:         if (contentIndex == CONTENT.length && content == null) {
michael@0:             content = Portability.newStringFromBuffer(strBuf, 0, strBufLen);
michael@0:             return;
michael@0:         }
michael@0:         if (charsetIndex == CHARSET.length && charset == null) {
michael@0:             charset = Portability.newStringFromBuffer(strBuf, 0, strBufLen);            
michael@0:             return;
michael@0:         }
michael@0:         if (httpEquivIndex == HTTP_EQUIV.length
michael@0:                 && httpEquivState == HTTP_EQUIV_NOT_SEEN) {
michael@0:             httpEquivState = (contentTypeIndex == CONTENT_TYPE.length) ? HTTP_EQUIV_CONTENT_TYPE
michael@0:                     : HTTP_EQUIV_OTHER;
michael@0:             return;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     private boolean handleTag() throws SAXException {
michael@0:         boolean stop = handleTagInner();
michael@0:         Portability.releaseString(content);
michael@0:         content = null;
michael@0:         Portability.releaseString(charset);
michael@0:         charset = null;
michael@0:         httpEquivState = HTTP_EQUIV_NOT_SEEN;
michael@0:         return stop;
michael@0:     }
michael@0:     
michael@0:     private boolean handleTagInner() throws SAXException {
michael@0:         if (charset != null && tryCharset(charset)) {
michael@0:                 return true;
michael@0:         }
michael@0:         if (content != null && httpEquivState == HTTP_EQUIV_CONTENT_TYPE) {
michael@0:             String extract = TreeBuilder.extractCharsetFromContent(content);
michael@0:             if (extract == null) {
michael@0:                 return false;
michael@0:             }
michael@0:             boolean success = tryCharset(extract);
michael@0:             Portability.releaseString(extract);
michael@0:             return success;
michael@0:         }
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Tries to switch to an encoding.
michael@0:      * 
michael@0:      * @param encoding
michael@0:      * @return <code>true</code> if successful
michael@0:      * @throws SAXException
michael@0:      */
michael@0:     protected abstract boolean tryCharset(String encoding) throws SAXException;
michael@0:     
michael@0: }