*** empty log message ***

From-SVN: r26796

libjava/java/util/zip/ZipInputStream.java

+/* Copyright (C) 1999  Cygnus Solutions
+
+   This file is part of libgcj.
+
+This software is copyrighted work licensed under the terms of the
+Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
+details.  */
+
+package java.util.zip;
+import java.io.*;
+
+/**
+ * @author Per Bothner
+ * @date May 1999.
+ */
+
+/*
+ * Written using on-line Java Platform 1.2 API Specification, as well
+ * as "The Java Class Libraries", 2nd edition (Addison-Wesley, 1998).
+ * Status:  Quite incomplete, but can read uncompressed .zip archives.
+ */
+
+// JDK1.2 has "protected ZipEntry createZipEntry(String)" but is very
+// vague about what the method does.  FIXME.
+// We do not calculate the CRC and compare it with the specified value;
+// we probably should.  FIXME.
+   
+
+public class ZipInputStream extends InflaterInputStream
+{
+  ZipEntry current;
+  int current_flags;
+  int avail;
+
+  public ZipInputStream (InputStream in)
+  {
+    super(in);
+  }
+
+  public ZipEntry getNextEntry () throws IOException
+  {
+    if (current != null)
+      closeZipEntry();
+    if (in.read() != 'P'
+	|| in.read() != 'K')
+      return null;
+    int code = in.read();
+    while (code == '\001')
+      {
+	code = in.read();
+	if (code != '\002')
+	  return null;
+	in.skip(16);
+	int size = read4();
+	in.skip(4);
+	int fname_length = readu2();
+	int extra_length = readu2();
+	int fcomment_length = readu2();
+	in.skip(12+fname_length+extra_length+fcomment_length+size);
+	if (in.read() != 'P' || in.read() != 'K')
+	  return null;
+	code = in.read();
+      }
+    if (code == '\005')
+      {
+	if (in.read() != '\006')
+	  return null;
+	in.skip(16);
+	int comment_size = readu2();
+	in.skip(comment_size);
+	if (in.read() != 'P' || in.read() != 'K')
+	  return null;
+	code = in.read();
+      }
+    if (code != '\003'
+	|| in.read() != '\004')
+      return null;
+    int ex_version = readu2();
+    current_flags = readu2();
+    int method = readu2();
+    int modtime = readu2();
+    int moddate = readu2();
+    int crc = read4();
+    int compressedSize = read4();
+    int uncompressedSize = read4();
+    int filenameLength = readu2();
+    int extraLength = readu2();
+    byte[] bname = new byte[filenameLength];
+    readFully(bname);
+    ZipEntry entry = new ZipEntry(new String(bname, "8859_1"));
+    if (extraLength > 0)
+      {
+	byte[] bextra = new byte[extraLength];
+	readFully(bextra);
+	entry.extra = bextra;
+      }
+    entry.compressedSize = compressedSize;
+    entry.size = uncompressedSize;
+    entry.crc = (long) crc & 0xffffffffL;
+    entry.method = method;
+    entry.time = ZipEntry.timeFromDOS(moddate, modtime);
+    current = entry;
+    avail = uncompressedSize;
+    return entry;
+  }
+
+  public int read (byte[] b, int off, int len)  throws IOException
+  {
+    if (len > avail)
+      len = avail;
+    int count = super.read(b, off, len);
+    if (count > 0)
+      avail -= count;
+    return count;
+  }
+
+  public long skip (long n)  throws IOException
+  {
+    if (n > avail)
+      n = avail;
+    long count = super.skip(n);
+    avail = avail - (int) count;
+    return count;
+  }
+
+  private void readFully (byte[] b)  throws IOException
+  {
+    int off = 0;
+    int len = b.length;
+    while (len > 0)
+      {
+	int count = in.read(b, off, len);
+	if (count <= 0)
+	  throw new EOFException(".zip archive ended prematurely");
+	off += count;
+	len -= count;
+      }
+  }
+
+  private int readu2 ()  throws IOException
+  {
+    int byte0 = in.read();
+    int byte1 = in.read();
+    if (byte0 < 0 || byte1 < 0)
+      throw new EOFException(".zip archive ended prematurely");
+    return ((byte1 & 0xFF) << 8) | (byte0 & 0xFF);
+  }
+
+  private int read4 () throws IOException
+  {
+    int byte0 = in.read();
+    int byte1 = in.read();
+    int byte2 = in.read();
+    int byte3 = in.read();
+    if (byte3 < 0)
+      throw new EOFException(".zip archive ended prematurely");
+    return ((byte3 & 0xFF) << 24) + ((byte2 & 0xFF) << 16)
+      + ((byte1 & 0xFF) << 8) + (byte0 & 0xFF);
+  }
+
+  public void closeZipEntry ()  throws IOException
+  {
+    if (current != null)
+      {
+	if (avail > 0)
+	  skip (avail);
+	if ((current_flags & 8) != 0)
+	  {
+	    int sig = read4();
+	    if (sig != 0x04034b50)
+	      throw new IOException("bad/missing magic number at end of .zip entry");
+	    int crc = read4();
+	    int compressedSize = read4();
+	    int uncompressedSize = read4();
+	    if (current.compressedSize != compressedSize
+		|| current.size != uncompressedSize
+		|| current.crc != crc)
+	      throw new IOException("bad data descriptor at end of .zip entry");
+	  }
+	current = null;
+	avail = 0;
+      }
+  }
+
+  public void close ()  throws IOException
+  {
+    current = null;
+    super.close();
+  }
+}