I noticed that this bug was marked RESOLVED/LATER and was wondering if there was any
way to get this into 3.2.2 since that is the version that is closest to being
released. I've already found 2 ways to fix this issue but am willing to abide by the
groups decision and concentrate on getting this into the 3.3 release instead.
The 2 ways to fix this are:
1. In BufferedServletInputStream, implement an available() method that returns limit
- bytesRead or 0 whichever is greater. The limit class variable is set to the value
of the Content-Length header and bytesRead is the number of bytes read since limit was
set (see the attached diff1.txt). This is the easy fix but doesn't address the
feature of available that says it will return the number of bytes that can be read
"without blocking". Obviously, if there is a large amount of data, a read will most
likely block at some point depending on how much is asked for, however this prevents a
condition where one of the adapters returns 0 because a read hasn't actually been
requested from the webserver.
2. Update BufferedServletInputStream to call reqA.available and then update the
following files to provide this interface:
Request.java
RequestImpl.java
HttpRequestAdapter.java
Ajp12ConnectionHandler.java
Ajp13ConnectorRequest.java
JNIConnectionHandler.java
MsgConnector.java
TcpConnector.java
Each of these classes would need to provide an appropriate available() method. I've
also done the work on these files as well (see the attached diff2.txt) but noticed
that since some of the protocols (particularly AJP13) actually have to request a read
to fill their internal buffer, the adapter (i.e. Ajp13ConnectorRequest.java) will
return a 0 if doRead is called and it exactly empties the internal buffer. Also the
JNIRequestAdapter (in JNIConnectionHandler.java) makes a native call back into the
webserver to do the reads and so available is implemented similar to #1 above; it just
returns the max of contentLength - bytesRead or 0. This was because I'm not sure of a
way to imp
After testing both of these, implementation 1 is actually faster and more reliable.
Typically if someone is calling available and they get back a 0, they would block the
thread anyways and so it makes some sense to let it block on the read plus it gets
around the issue of an adapter requiring one of it's read methods to be called to
actually have something available.
Any response positive or negative would be appreciated so that I know where to focus
my energy (i.e. 3.2.2 or 3.3).
Index: BufferedServletInputStream.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/core/Attic/BufferedServletInputStream.java,v
retrieving revision 1.8
diff -u -r1.8 BufferedServletInputStream.java
--- BufferedServletInputStream.java 2000/05/26 17:32:04 1.8
+++ BufferedServletInputStream.java 2001/03/21 21:03:59
@@ -151,6 +151,10 @@
}
}
+ public int available() throws IOException {
+ return Math.max((limit - bytesRead), 0);
+ }
+
// /**
// * @deprecated Not part of Servlet API, without it we can avoid a lot of GC.
Index: BufferedServletInputStream.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/core/Attic/BufferedServletInputStream.java,v
retrieving revision 1.8
diff -u -r1.8 BufferedServletInputStream.java
--- BufferedServletInputStream.java 2000/05/26 17:32:04 1.8
+++ BufferedServletInputStream.java 2001/03/21 21:04:23
@@ -151,6 +151,10 @@
}
}
+ public int available() throws IOException {
+ return reqA.available();
+ }
+
// /**
// * @deprecated Not part of Servlet API, without it we can avoid a lot of GC.
Index: Request.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/core/Request.java,v
retrieving revision 1.46
diff -u -r1.46 Request.java
--- Request.java 2000/06/22 19:49:35 1.46
+++ Request.java 2001/03/21 21:05:31
@@ -274,6 +274,9 @@
public int doRead( byte b[], int off, int len ) throws IOException;
+ // provide a way to overload available from InputStream
+ public int available() throws IOException;
+
// -------------------- Internal methods --------------------
/** Support for "pools"
*/
Index: RequestImpl.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/core/Attic/RequestImpl.java,v
retrieving revision 1.52.2.7
diff -u -r1.52.2.7 RequestImpl.java
--- RequestImpl.java 2001/03/15 19:00:37 1.52.2.7
+++ RequestImpl.java 2001/03/21 21:05:41
@@ -818,6 +818,11 @@
return -1;
}
+ // provide a way to overload available from InputStream
+ public int available() throws IOException {
+ return 0;
+ }
+
// -------------------- "cooked" info --------------------
// Hints = return null if you don't know,
// and Tom will find the value. You can also use the static
Index: HttpRequestAdapter.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/http/Attic/HttpRequestAdapter.java,v
retrieving revision 1.16.2.6
diff -u -r1.16.2.6 HttpRequestAdapter.java
--- HttpRequestAdapter.java 2001/01/13 18:36:27 1.16.2.6
+++ HttpRequestAdapter.java 2001/03/21 21:10:44
@@ -119,6 +119,11 @@
return sin.read(b, off, len);
}
+ // provide a way to overload available from InputStream
+ public int available() throws IOException {
+ return Math.max(sin.available(), 0);
+ }
+
public void readNextRequest(Response response) throws IOException {
// Odd, but works: we use the ServletInputStream, which uses doRead.
Index: Ajp12ConnectionHandler.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/connector/Attic/Ajp12ConnectionHandler.java,v
retrieving revision 1.28.2.2
diff -u -r1.28.2.2 Ajp12ConnectionHandler.java
--- Ajp12ConnectionHandler.java 2000/11/10 06:42:51 1.28.2.2
+++ Ajp12ConnectionHandler.java 2001/03/21 21:17:19
@@ -193,6 +193,10 @@
return ajpin.read(b,off,len);
}
+ public int available() throws IOException {
+ return Math.max(ajpin.available(), 0);
+ }
+
void log( String s ) {
contextM.log( s );
}
Index: Ajp13ConnectorRequest.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/connector/Attic/Ajp13ConnectorRequest.java,v
retrieving revision 1.5.2.5
diff -u -r1.5.2.5 Ajp13ConnectorRequest.java
--- Ajp13ConnectorRequest.java 2001/02/14 22:19:55 1.5.2.5
+++ Ajp13ConnectorRequest.java 2001/03/21 21:14:39
@@ -288,6 +288,10 @@
return len - toCopy;
}
+ public int available() throws IOException {
+ return Math.max((blen - pos) + con.available(), 0);
+ }
+
public void recycle()
{
super.recycle();
Index: JNIConnectionHandler.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/connector/Attic/JNIConnectionHandler.java,v
retrieving revision 1.9.2.2
diff -u -r1.9.2.2 JNIConnectionHandler.java
--- JNIConnectionHandler.java 2000/12/12 09:41:44 1.9.2.2
+++ JNIConnectionHandler.java 2001/03/21 21:15:16
@@ -213,6 +213,7 @@
JNIConnectionHandler h;
long s;
long l;
+ int bytesRead;
public int doRead() throws IOException {
byte []b = new byte[1];
@@ -234,7 +235,16 @@
Thread.currentThread().yield();
}
}
+
+ if (contentLength > 0)
+ bytesRead += rc;
+
return rc;
+ }
+
+ // provide a way to overload available from InputStream
+ public int available() throws IOException {
+ return Math.max(contentLength - bytesRead, 0);
}
public JNIRequestAdapter(ContextManager cm,
Index: MsgConnector.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/connector/Attic/MsgConnector.java,v
retrieving revision 1.5.2.1
diff -u -r1.5.2.1 MsgConnector.java
--- MsgConnector.java 2000/12/12 09:41:44 1.5.2.1
+++ MsgConnector.java 2001/03/21 21:15:45
@@ -84,4 +84,8 @@
public int receive(MsgBuffer msg) throws IOException;
public void close() throws IOException;
+
+ // provide a way to overload available from InputStream
+ public int available() throws IOException;
}
+
Index: TcpConnector.java
===================================================================
RCS file:
/home/cvspublic/jakarta-tomcat/src/share/org/apache/tomcat/service/connector/Attic/TcpConnector.java,v
retrieving revision 1.2.2.2
diff -u -r1.2.2.2 TcpConnector.java
--- TcpConnector.java 2000/12/12 09:41:44 1.2.2.2
+++ TcpConnector.java 2001/03/21 21:16:01
@@ -175,4 +175,14 @@
in.close();
}
}
+
+ // provide a way to overload available from InputStream
+ public int available() throws IOException {
+ if (null != in) {
+ System.out.println("in.available() = " + in.available());
+ return in.available();
+ }
+ else
+ return 0;
+ }
}
