Initial revision

From-SVN: r102074

libjava/classpath/gnu/java/net/CRLFInputStream.java

@@ -0,0 +1,174 @@
+/* CRLFInputStream.java --
+   Copyright (C) 2002, 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.net;
+
+import java.io.BufferedInputStream;
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+/**
+ * An input stream that filters out CR/LF pairs into LFs.
+ *
+ * @author Chris Burdess (dog@gnu.org)
+ */
+public class CRLFInputStream
+  extends FilterInputStream
+{
+  /**
+   * The CR octet.
+   */
+  public static final int CR = 13;
+
+  /**
+   * The LF octet.
+   */
+  public static final int LF = 10;
+
+  private boolean doReset;
+
+  /**
+   * Constructs a CR/LF input stream connected to the specified input
+   * stream.
+   */
+  public CRLFInputStream(InputStream in)
+  {
+    super(in.markSupported() ? in : new BufferedInputStream(in));
+  }
+
+  /**
+   * Reads the next byte of data from this input stream.
+   * Returns -1 if the end of the stream has been reached.
+   * @exception IOException if an I/O error occurs
+   */
+  public int read()
+    throws IOException
+  {
+    int c = in.read();
+    if (c == CR)
+      {
+        in.mark(1);
+        int d = in.read();
+        if (d == LF)
+          {
+            c = d;
+          }
+        else
+          {
+            in.reset();
+          }
+      }
+    return c;
+  }
+  
+  /**
+   * Reads up to b.length bytes of data from this input stream into
+   * an array of bytes.
+   * Returns -1 if the end of the stream has been reached.
+   * @exception IOException if an I/O error occurs
+   */
+  public int read(byte[] b)
+    throws IOException
+  {
+    return read(b, 0, b.length);
+  }
+
+  /**
+   * Reads up to len bytes of data from this input stream into an
+   * array of bytes, starting at the specified offset.
+   * Returns -1 if the end of the stream has been reached.
+   * @exception IOException if an I/O error occurs
+   */
+  public int read(byte[] b, int off, int len)
+    throws IOException
+  {
+    in.mark(len + 1);
+    int l = in.read(b, off, len);
+    if (l > 0)
+      {
+        int i = indexOfCRLF(b, off, l);
+        if (doReset)
+          {
+            in.reset();
+            if (i != -1)
+              {
+                l = in.read(b, off, i + 1); // read to CR
+                in.read(); // skip LF
+                b[i] = LF; // fix CR as LF
+              }
+            else
+              {
+                l = in.read(b, off, len); // CR(s) but no LF
+              }
+          }
+      }
+    return l;
+  }
+
+  private int indexOfCRLF(byte[] b, int off, int len)
+    throws IOException
+  {
+    doReset = false;
+    int lm1 = len - 1;
+    for (int i = off; i < len; i++)
+      {
+        if (b[i] == CR)
+          {
+            int d;
+            if (i == lm1)
+              {
+                d = in.read();
+                doReset = true;
+              }
+            else
+              {
+                d = b[i + 1];
+              }
+            if (d == LF)
+              {
+                doReset = true;
+                return i;
+              }
+          }
+      }
+    return -1;
+  }
+
+}
+