A brief file description. More...

#include "ProxyConfig.h"
#include "P_Net.h"
#include "MimeTable.h"
#include "TransformInternal.h"
#include "HdrUtils.h"
#include "Log.h"

Include dependency graph for Transform.cc:

Go to the source code of this file.

Defines
#define	ART 1
#define	AGIF 2
#define	RETRY()
#define	RANGE_NUMBERS_LENGTH 60
Variables
TransformProcessor	transformProcessor
static char	bound [] = "RANGE_SEPARATOR"
static char	range_type [] = "multipart/byteranges; boundary=RANGE_SEPARATOR"
static char	cont_type [] = "Content-type: "
static char	cont_range [] = "Content-range: bytes "

Detailed Description

A brief file description.

License

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Transform thoughts

Must be able to handle a chain of transformations.
Any transformation in the chain may fail. Failure options:
- abort the client (if transformed data already sent)
- serve the client the untransformed document
- remove the failing transformation from the chain and attempt the transformation again (difficult to do)
- never send untransformed document to client if client would not understand it (e.g. a set top box)
Must be able to change response header fields up until the point that TRANSFORM_READ_READY is sent to the user.

Transform usage

transformProcessor.open (cont, hooks); - returns "tvc", a TransformVConnection if 'hooks != NULL'
tvc->do_io_write (cont, nbytes, buffer1);
cont->handleEvent (TRANSFORM_READ_READY, NULL);
tvc->do_io_read (cont, nbytes, buffer2);
tvc->do_io_close ();

Transform visualization

         +----+     +----+     +----+     +----+
    -IB->| T1 |-B1->| T2 |-B2->| T3 |-B3->| T4 |-OB->
         +----+     +----+     +----+     +----+

Data flows into the first transform in the form of the buffer passed to TransformVConnection::do_io_write (IB). Data flows out of the last transform in the form of the buffer passed to TransformVConnection::do_io_read (OB). Between each transformation is another buffer (B1, B2 and B3).

A transformation is a Continuation. The continuation is called with the event TRANSFORM_IO_WRITE to initialize the write and TRANSFORM_IO_READ to initialize the read.

Definition in file Transform.cc.

Define Documentation

#define AGIF 2

Definition at line 71 of file Transform.cc.

#define ART 1

Definition at line 70 of file Transform.cc.

#define RANGE_NUMBERS_LENGTH 60

Definition at line 965 of file Transform.cc.

Referenced by RangeTransform::add_sub_header().

#define RETRY ( )

Value:

if (ink_atomic_increment ((int*) &m_event_count, 1) < 0) { \
        ink_assert (!"not reached"); \
    } \
    eventProcessor.schedule_in (this, HRTIME_MSECONDS (10), ET_NET); \
    return 0;

Definition at line 133 of file Transform.cc.

Referenced by HdrHeap::allocate_str(), HdrHeap::attach_block(), and TransformTerminus::handle_event().