Android Open Source - vanilindy Common

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License

The source code is released under:

Apache License

Java Source Code

/*
 * Copyright (C) 2013 Adrian Ulrich <adrian@blinkenlights.ch>
 */*  www  . j ava  2s.  c  om*/
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>. 
 */


package ch.blinkenlights.bastp;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.HashMap;
import java.util.Vector;

public class Common {
  private static final long MAX_PKT_SIZE = 8388608;
  
  public void xdie(String reason) throws IOException {
    throw new IOException(reason);
  }
  
  /*
  ** Returns a 32bit int from given byte offset in LE
  */
  public int b2le32(byte[] b, int off) {
    int r = 0;
    for(int i=0; i<4; i++) {
      r |= ( b2u(b[off+i]) << (8*i) );
    }
    return r;
  }
  
  public int b2be32(byte[] b, int off) {
    return swap32(b2le32(b, off));
  }
  
  public int swap32(int i) {
    return((i&0xff)<<24)+((i&0xff00)<<8)+((i&0xff0000)>>8)+((i>>24)&0xff);
  }
  
  /*
  ** convert 'byte' value into unsigned int
  */
  public int b2u(byte x) {
    return (x & 0xFF);
  }
  
  /*
  ** Printout debug message to STDOUT
  */
  public void debug(String s) {
    System.out.println("DBUG "+s);
  }
  
  public HashMap parse_vorbis_comment(RandomAccessFile s, long offset, long payload_len) throws IOException {
    HashMap tags = new HashMap();
    int comments   = 0;                // number of found comments 
    int xoff       = 0;                // offset within 'scratch'
    int can_read   = (int)(payload_len > MAX_PKT_SIZE ? MAX_PKT_SIZE : payload_len);
    byte[] scratch = new byte[can_read];
    
    // seek to given position and slurp in the payload
    s.seek(offset);
    s.read(scratch);
    
    // skip vendor string in format: [LEN][VENDOR_STRING] 
    xoff    += 4 + b2le32(scratch, xoff); // 4 = LEN = 32bit int 
    comments = b2le32(scratch, xoff);
    xoff    += 4;
    
    // debug("comments count = "+comments);
    for(int i=0; i<comments; i++) {
      
      int clen = (int)b2le32(scratch, xoff);
      xoff += 4+clen;
      
      if(xoff > scratch.length)
        xdie("string out of bounds");
      
      String   tag_raw = new String(scratch, xoff-clen, clen);
      String[] tag_vec = tag_raw.split("=",2);
      String   tag_key = tag_vec[0].toUpperCase();
      
      addTagEntry(tags, tag_key, tag_vec[1]);
    }
    return tags;
  }
  
  public void addTagEntry(HashMap tags, String key, String value) {
    if(tags.containsKey(key)) {
      ((Vector)tags.get(key)).add(value); // just add to existing vector
    }
    else {
      Vector vx = new Vector();
      vx.add(value);
      tags.put(key, vx);
    }
  }
  
}

Java Source Code List

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