From abbc94d159eaeb1e17b7676ec021a8e59db81183 Mon Sep 17 00:00:00 2001
From: Florian Angerer <florian.angerer@oracle.com>
Date: Wed, 1 Mar 2017 13:53:24 +0100
Subject: [PATCH] Fixed serious bug during decoding: Did not properly use the
decoder when reading single 'elements' from a connection using method 'getc'.
An element is either a character or a byte depending on the connection mode
text or binary, respectively. Now, a stream decoder is created on demand and
used for any subsequent character-based reading. As in GnuR, mixing binary-
and text-based reading and writing leads to undefined behavior since the
decoder may already have consumed some bytes.
---
.../r/runtime/conn/ConnectionSupport.java | 2 +-
.../r/runtime/conn/DelegateRConnection.java | 82 +++++++++++++------
.../runtime/conn/DelegateReadRConnection.java | 18 ++--
.../conn/DelegateReadWriteRConnection.java | 6 +-
.../truffle/r/runtime/conn/RConnection.java | 15 +++-
5 files changed, 90 insertions(+), 33 deletions(-)
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/ConnectionSupport.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/ConnectionSupport.java
index b772be488a..3e0941dce2 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/ConnectionSupport.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/ConnectionSupport.java
@@ -1061,7 +1061,7 @@ public class ConnectionSupport {
if (conn instanceof BaseRConnection) {
return (BaseRConnection) conn;
} else if (conn instanceof DelegateReadRConnection) {
- return ((DelegateReadRConnection) conn).base;
+ return ((DelegateRConnection) conn).base;
} else {
throw RInternalError.shouldNotReachHere();
}
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateRConnection.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateRConnection.java
index 91359d131f..0139c2e9a7 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateRConnection.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateRConnection.java
@@ -30,6 +30,8 @@ import java.nio.channels.ReadableByteChannel;
import java.nio.channels.SeekableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.nio.charset.Charset;
+import java.nio.charset.CharsetDecoder;
+import java.nio.charset.CodingErrorAction;
import java.util.ArrayList;
import java.util.Objects;
@@ -52,6 +54,7 @@ import sun.nio.cs.StreamDecoder;
*/
abstract class DelegateRConnection implements RConnection {
protected final BaseRConnection base;
+ private StreamDecoder decoder;
DelegateRConnection(BaseRConnection base) {
this.base = Objects.requireNonNull(base);
@@ -275,34 +278,54 @@ abstract class DelegateRConnection implements RConnection {
return new String(chars, 0, j);
}
- public static String readCharHelper(int nchars, ReadableByteChannel channel, boolean useBytes) throws IOException {
- if (useBytes) {
- ByteBuffer buf = ByteBuffer.allocate(nchars);
- channel.read(buf);
- int j = 0;
- for (; j < buf.position(); j++) {
- // strings end at 0
- if (buf.get(j) == 0) {
- break;
- }
+ /**
+ * Reads a specified number of single-byte characters.<br>
+ * <p>
+ * This method is meant to be used if R's function {@code readChar} is called with parameter
+ * {@code useBytes=TRUE}.
+ * </p>
+ *
+ * @param nchars The number of single-byte characters to read.
+ * @param channel The channel to read from (must not be {@code null}).
+ * @throws IOException
+ */
+ public static String readCharHelper(int nchars, ReadableByteChannel channel) throws IOException {
+ ByteBuffer buf = ByteBuffer.allocate(nchars);
+ channel.read(buf);
+ int j = 0;
+ for (; j < buf.position(); j++) {
+ // strings end at 0
+ if (buf.get(j) == 0) {
+ break;
}
+ }
- return new String(buf.array(), 0, j);
- } else {
- // we need a decoder
- StreamDecoder decoder = StreamDecoder.forDecoder(channel, Charset.defaultCharset().newDecoder(), nchars);
- char[] chars = new char[nchars];
- decoder.read(chars);
- int j = 0;
- for (; j < chars.length; j++) {
- // strings end at 0
- if (chars[j] == 0) {
- break;
- }
- }
+ return new String(buf.array(), 0, j);
+ }
- return new String(chars, 0, j);
+ /**
+ * Reads a specified number of characters (not bytes).<br>
+ * <p>
+ * This method is meant to be used if R's function {@code readChar} is called with parameter
+ * {@code useBytes=FALSE}.
+ * </p>
+ *
+ * @param nchars The number of characters to read.
+ * @param decoder The stream decoder to use (must not be {@code null}).
+ * @throws IOException
+ */
+ public static String readCharHelper(int nchars, StreamDecoder decoder) throws IOException {
+ // we need a decoder
+ char[] chars = new char[nchars];
+ decoder.read(chars);
+ int j = 0;
+ for (; j < chars.length; j++) {
+ // strings end at 0
+ if (chars[j] == 0) {
+ break;
+ }
}
+ return new String(chars, 0, j);
}
/**
@@ -355,4 +378,15 @@ abstract class DelegateRConnection implements RConnection {
public void pushBack(RAbstractStringVector lines, boolean addNewLine) {
throw RInternalError.shouldNotReachHere();
}
+
+ /**
+ * Creates the stream decoder on demand and returns it.
+ */
+ protected StreamDecoder getDecoder() throws IOException {
+ if (decoder == null) {
+ CharsetDecoder charsetEncoder = base.getEncoding().newDecoder().onMalformedInput(CodingErrorAction.REPLACE).onUnmappableCharacter(CodingErrorAction.REPLACE);
+ decoder = StreamDecoder.forDecoder(getChannel(), charsetEncoder, -1);
+ }
+ return decoder;
+ }
}
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadRConnection.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadRConnection.java
index d317847217..70a2bac8df 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadRConnection.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadRConnection.java
@@ -63,15 +63,23 @@ public abstract class DelegateReadRConnection extends DelegateRConnection {
@Override
public int getc() throws IOException {
- tmp.clear();
- int nread = getChannel().read(tmp);
- tmp.rewind();
- return nread > 0 ? tmp.get() : -1;
+ if (isTextMode()) {
+ return getDecoder().read();
+ } else {
+ tmp.clear();
+ int nread = getChannel().read(tmp);
+ tmp.rewind();
+ return nread > 0 ? tmp.get() : -1;
+ }
}
@Override
public String readChar(int nchars, boolean useBytes) throws IOException {
- return DelegateRConnection.readCharHelper(nchars, getChannel(), useBytes);
+ if (useBytes) {
+ return DelegateRConnection.readCharHelper(nchars, getChannel());
+ } else {
+ return DelegateRConnection.readCharHelper(nchars, getDecoder());
+ }
}
@Override
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadWriteRConnection.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadWriteRConnection.java
index 664f74183e..011cf49d1b 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadWriteRConnection.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/DelegateReadWriteRConnection.java
@@ -59,7 +59,11 @@ abstract class DelegateReadWriteRConnection extends DelegateRConnection {
@Override
public String readChar(int nchars, boolean useBytes) throws IOException {
- return DelegateRConnection.readCharHelper(nchars, getChannel(), useBytes);
+ if (useBytes) {
+ return DelegateRConnection.readCharHelper(nchars, getChannel());
+ } else {
+ return DelegateRConnection.readCharHelper(nchars, getDecoder());
+ }
}
@Override
diff --git a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/RConnection.java b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/RConnection.java
index 761e543d6c..341d12e3ba 100644
--- a/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/RConnection.java
+++ b/com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/conn/RConnection.java
@@ -43,12 +43,23 @@ public interface RConnection extends AutoCloseable {
}
/**
- * Return the underlying input stream (for internal use).
+ * Return the underlying input stream (for internal use).<br>
+ * <p>
+ * <b>NOTE:</b> The connection may do some caching internally! Therefore, the behavior is
+ * undefined if you mix using the input stream directly and using the read methods of the
+ * connection.
+ * </p>
+ *
*/
InputStream getInputStream() throws IOException;
/**
- * Return the underlying output stream (for internal use).
+ * Return the underlying output stream (for internal use).<br>
+ * <p>
+ * <b>NOTE:</b> The connection may do some caching internally! Therefore, the behavior is
+ * undefined if you mix using the output stream directly and using the write methods of the
+ * connection.
+ * </p>
*/
OutputStream getOutputStream() throws IOException;
--
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