Initial revision

From-SVN: r102074

1 files changed, 216 insertions, 0 deletions

diff --git a/libjava/classpath/gnu/java/io/Base64InputStream.java b/libjava/classpath/gnu/java/io/Base64InputStream.java
new file mode 100644
index 0000000..b0824ab
--- /dev/null
+++ b/libjava/classpath/gnu/java/io/Base64InputStream.java
@@ -0,0 +1,216 @@
+/* Base64InputStream.java -- base-64 input stream.
+   Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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 2, or (at your option)
+any later version.
+ 
+GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.io;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * A filter input stream that decodes data encoded in the Base-64
+ * encoding scheme.
+ *
+ * @author Casey Marshall (rsdio@metastatic.org)
+ */
+public class Base64InputStream extends FilterInputStream
+{
+
+  // Constants and fields.
+  // ------------------------------------------------------------------------
+
+  /** Base-64 digits. */
+  private static final String BASE_64 = 
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+  /** Base-64 padding character. */
+  private static final char BASE_64_PAD = '=';
+
+  /** Decoding state. */
+  private int state;
+
+  /** Intermediate decoded value. */
+  private int temp;
+
+  /** EOF flag. */
+  private boolean eof;
+
+  private final byte[] one = new byte[1];
+
+  // Constructors.
+  // ------------------------------------------------------------------------
+
+  /**
+   * Create a new Base-64 input stream. The input bytes must be the
+   * ASCII characters A-Z, a-z, 0-9, + and /, with optional whitespace,
+   * and will be decoded into a byte stream.
+   *
+   * @param in The source of Base-64 input.
+   */
+  public Base64InputStream(InputStream in)
+  {
+    super(in);
+    state = 0;
+    temp = 0;
+    eof = false;
+  }
+
+  // Class method.
+  // ------------------------------------------------------------------------
+
+  /**
+   * Decode a single Base-64 string to a byte array.
+   *
+   * @param base64 The Base-64 encoded data.
+   * @return The decoded bytes.
+   * @throws IOException If the given data do not compose a valid Base-64
+   *  sequence.
+   */
+  public static byte[] decode(String base64) throws IOException
+  {
+    Base64InputStream in =
+      new Base64InputStream(new ByteArrayInputStream(base64.getBytes()));
+    ByteArrayOutputStream out =
+      new ByteArrayOutputStream((int) (base64.length() / 0.666));
+    byte[] buf = new byte[1024];
+    int len;
+    while ((len = in.read(buf)) != -1)
+      out.write(buf, 0, len);
+    return out.toByteArray();
+  }
+
+  // Instance methods.
+  // ------------------------------------------------------------------------
+
+  public int available()
+  {
+    return 0;
+  }
+
+  public int read() throws IOException
+  {
+    if (read(one) == 1)
+      return one[0];
+    return -1;
+  }
+
+  public int read(byte[] buf, int off, int len) throws IOException
+  {
+    if (eof)
+      return -1;
+    int count = 0;
+    while (count < len)
+      {
+        int i;
+        while (Character.isWhitespace((char) (i = in.read())));
+        int pos = BASE_64.indexOf((char) i);
+        if (pos >= 0)
+          {
+            switch (state)
+              {
+                case 0:
+                  temp = pos << 2;
+                  state = 1;
+                  break;
+                case 1:
+                  buf[count++] = (byte) (temp | (pos >>> 4));
+                  temp = (pos & 0x0F) << 4;
+                  state = 2;
+                  break;
+                case 2:
+                  buf[count++] = (byte) (temp | (pos >>> 2));
+                  temp = (pos & 0x03) << 6;
+                  state = 3;
+                  break;
+                case 3:
+                  buf[count++] = (byte) (temp | pos);
+                  state = 0;
+                  break;
+              }
+          }
+        else if (i == BASE_64_PAD)
+          {
+            switch (state)
+              {
+                case 0:
+                case 1:
+                  throw new IOException("malformed Base-64 input");
+                case 2:
+                  while (Character.isWhitespace((char) (i = in.read())));
+                  if (i != BASE_64_PAD)
+                    throw new IOException("malformed Base-64 input");
+                case 3:
+                  while (Character.isWhitespace((char) (i = in.read())));
+              }
+            eof = true;
+            break;
+          }
+        else  // First non-Base-64 character, consider it end-of-stream.
+          {
+            if (state != 0)
+              throw new IOException("malformed Base-64 input");
+            eof = true;
+            break;
+          }
+      }
+      return count;
+  }
+
+  public boolean markSupported()
+  {
+    return false;
+  }
+
+  public void mark(int markLimit) { }
+
+  public void reset() throws IOException
+  {
+    throw new IOException("reset not supported");
+  }
+
+  public long skip(long n) throws IOException
+  {
+    long skipped;
+    for (skipped = 0; skipped < n; skipped++)
+      if (read() == -1)
+        break;
+    return skipped;
+  }
+}