vfs: check userland buffers before reading them.

[haiku.git] / src / apps / cortex / addons / Flanger / FlangerNode.cpp

/*
 * Copyright (c) 1999-2000, Eric Moon.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions, and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


// FlangerNode.cpp
// e.moon 16jun99

#include "FlangerNode.h"

#include "AudioBuffer.h"
#include "SoundUtils.h"

#include <Buffer.h>
#include <BufferGroup.h>
#include <ByteOrder.h>
#include <Debug.h>
#include <ParameterWeb.h>
#include <TimeSource.h>

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>

// -------------------------------------------------------- //
// local helpers
// -------------------------------------------------------- //

float calc_sweep_delta(
        const media_raw_audio_format& format,
        float fRate);

float calc_sweep_base(
        const media_raw_audio_format& format,
        float fDelay, float fDepth);

float calc_sweep_factor(
        const media_raw_audio_format& format,
        float fDepth);

// -------------------------------------------------------- //
// constants
// -------------------------------------------------------- //

// input-ID symbols
enum input_id_t {
        ID_AUDIO_INPUT
};

// output-ID symbols
enum output_id_t {
        ID_AUDIO_MIX_OUTPUT
        //ID_AUDIO_WET_OUTPUT ...
};

// parameter ID
enum param_id_t {
        P_MIX_RATIO_LABEL               = 100,
        P_MIX_RATIO,

        P_SWEEP_RATE_LABEL      = 200,
        P_SWEEP_RATE,

        P_DELAY_LABEL                           = 300,
        P_DELAY,

        P_DEPTH_LABEL                           = 400,
        P_DEPTH,

        P_FEEDBACK_LABEL                = 500,
        P_FEEDBACK
};

const float FlangerNode::s_fMaxDelay = 100.0;
const char* const FlangerNode::s_nodeName = "FlangerNode";


// -------------------------------------------------------- //
// ctor/dtor
// -------------------------------------------------------- //

FlangerNode::~FlangerNode() {
        // shut down
        Quit();

        // free delay buffer
        if(m_pDelayBuffer)
                delete m_pDelayBuffer;
}

FlangerNode::FlangerNode(BMediaAddOn* pAddOn) :
        // * init base classes
        BMediaNode(s_nodeName), // (virtual base)
        BBufferConsumer(B_MEDIA_RAW_AUDIO),
        BBufferProducer(B_MEDIA_RAW_AUDIO),
        BControllable(),
        BMediaEventLooper(),

        // * init connection state
        m_outputEnabled(true),
        m_downstreamLatency(0),
        m_processingLatency(0),

        // * init filter state
        m_pDelayBuffer(0),

        // * init add-on stuff
        m_pAddOn(pAddOn) {

//      PRINT((
//              "\n"
//              "--*-- FlangerNode() [%s] --*--\n\n",
//              __BUILD_DATE));
//
        // the rest of the initialization happens in NodeRegistered().
}


// -------------------------------------------------------- //
// *** BMediaNode
// -------------------------------------------------------- //

status_t FlangerNode::HandleMessage(
        int32 code,
        const void* pData,
        size_t size) {

        // pass off to each base class
        if(
                BBufferConsumer::HandleMessage(code, pData, size) &&
                BBufferProducer::HandleMessage(code, pData, size) &&
                BControllable::HandleMessage(code, pData, size) &&
                BMediaNode::HandleMessage(code, pData, size))
                BMediaNode::HandleBadMessage(code, pData, size);

        // +++++ return error on bad message?
        return B_OK;
}

BMediaAddOn* FlangerNode::AddOn(
        int32* poID) const {

        if(m_pAddOn)
                *poID = 0;
        return m_pAddOn;
}

void FlangerNode::SetRunMode(
        run_mode mode) {

        // disallow offline mode for now
        // +++++
        if(mode == B_OFFLINE)
                ReportError(B_NODE_FAILED_SET_RUN_MODE);

        // +++++ any other work to do?

        // hand off
        BMediaEventLooper::SetRunMode(mode);
}

// -------------------------------------------------------- //
// *** BMediaEventLooper
// -------------------------------------------------------- //

void FlangerNode::HandleEvent(
        const media_timed_event* pEvent,
        bigtime_t howLate,
        bool realTimeEvent) {

        ASSERT(pEvent);

        switch(pEvent->type) {
                case BTimedEventQueue::B_PARAMETER:
                        handleParameterEvent(pEvent);
                        break;

                case BTimedEventQueue::B_START:
                        handleStartEvent(pEvent);
                        break;

                case BTimedEventQueue::B_STOP:
                        handleStopEvent(pEvent);
                        break;

                default:
                        ignoreEvent(pEvent);
                        break;
        }
}

// "The Media Server calls this hook function after the node has
//  been registered.  This is derived from BMediaNode; BMediaEventLooper
//  implements it to call Run() automatically when the node is registered;
//  if you implement NodeRegistered() you should call through to
//  BMediaEventLooper::NodeRegistered() after you've done your custom
//  operations."

void FlangerNode::NodeRegistered() {

        PRINT(("FlangerNode::NodeRegistered()\n"));

        // figure preferred ('template') format
        m_preferredFormat.type = B_MEDIA_RAW_AUDIO;
        getPreferredFormat(m_preferredFormat);

        // initialize current format
        m_format.type = B_MEDIA_RAW_AUDIO;
        m_format.u.raw_audio = media_raw_audio_format::wildcard;

        // init input
        m_input.destination.port = ControlPort();
        m_input.destination.id = ID_AUDIO_INPUT;
        m_input.node = Node();
        m_input.source = media_source::null;
        m_input.format = m_format;
        strncpy(m_input.name, "Audio Input", B_MEDIA_NAME_LENGTH);

        // init output
        m_output.source.port = ControlPort();
        m_output.source.id = ID_AUDIO_MIX_OUTPUT;
        m_output.node = Node();
        m_output.destination = media_destination::null;
        m_output.format = m_format;
        strncpy(m_output.name, "Mix Output", B_MEDIA_NAME_LENGTH);

        // init parameters
        initParameterValues();
        initParameterWeb();

        // Start the BMediaEventLooper thread
        SetPriority(B_REAL_TIME_PRIORITY);
        Run();
}

// "Augment OfflineTime() to compute the node's current time; it's called
//  by the Media Kit when it's in offline mode. Update any appropriate
//  internal information as well, then call through to the BMediaEventLooper
//  implementation."

bigtime_t FlangerNode::OfflineTime() {
        // +++++
        return 0LL;
}

// -------------------------------------------------------- //
// *** BBufferConsumer
// -------------------------------------------------------- //

status_t FlangerNode::AcceptFormat(
        const media_destination& destination,
        media_format* pioFormat) {

        PRINT(("FlangerNode::AcceptFormat()\n"));

        // sanity checks
        if(destination != m_input.destination) {
                PRINT(("\tbad destination\n"));
                return B_MEDIA_BAD_DESTINATION;
        }
        if(pioFormat->type != B_MEDIA_RAW_AUDIO) {
                PRINT(("\tnot B_MEDIA_RAW_AUDIO\n"));
                return B_MEDIA_BAD_FORMAT;
        }

        validateProposedFormat(
                (m_format.u.raw_audio.format != media_raw_audio_format::wildcard.format) ?
                        m_format : m_preferredFormat,
                *pioFormat);
        return B_OK;
}

// "If you're writing a node, and receive a buffer with the B_SMALL_BUFFER
//  flag set, you must recycle the buffer before returning."

void FlangerNode::BufferReceived(
        BBuffer* pBuffer) {
        ASSERT(pBuffer);

        // check buffer destination
        if(pBuffer->Header()->destination !=
                m_input.destination.id) {
                PRINT(("FlangerNode::BufferReceived():\n"
                        "\tBad destination.\n"));
                pBuffer->Recycle();
                return;
        }

        if(pBuffer->Header()->time_source != TimeSource()->ID()) {
                PRINT(("* timesource mismatch\n"));
        }

        // check output
        if(m_output.destination == media_destination::null ||
                !m_outputEnabled) {
                pBuffer->Recycle();
                return;
        }

        // process and retransmit buffer
        filterBuffer(pBuffer);

        status_t err = SendBuffer(pBuffer, m_output.source, m_output.destination);
        if (err < B_OK) {
                PRINT(("FlangerNode::BufferReceived():\n"
                        "\tSendBuffer() failed: %s\n", strerror(err)));
                pBuffer->Recycle();
        }
        // sent!
}

// * make sure to fill in poInput->format with the contents of
//   pFormat; as of R4.5 the Media Kit passes poInput->format to
//   the producer in BBufferProducer::Connect().

status_t
FlangerNode::Connected(const media_source& source,
        const media_destination& destination, const media_format& format,
        media_input* poInput)
{
        PRINT(("FlangerNode::Connected()\n"
                "\tto source %" B_PRId32 "\n", source.id));

        // sanity check
        if(destination != m_input.destination) {
                PRINT(("\tbad destination\n"));
                return B_MEDIA_BAD_DESTINATION;
        }
        if(m_input.source != media_source::null) {
                PRINT(("\talready connected\n"));
                return B_MEDIA_ALREADY_CONNECTED;
        }

        // initialize input
        m_input.source = source;
        m_input.format = format;
        *poInput = m_input;

        // store format (this now constrains the output format)
        m_format = format;

        return B_OK;
}

void FlangerNode::Disconnected(
        const media_source& source,
        const media_destination& destination) {

        PRINT(("FlangerNode::Disconnected()\n"));

        // sanity checks
        if(m_input.source != source) {
                PRINT(("\tsource mismatch: expected ID %" B_PRId32 ", got %" B_PRId32
                                "\n", m_input.source.id, source.id));
                return;
        }
        if(destination != m_input.destination) {
                PRINT(("\tdestination mismatch: expected ID %" B_PRId32 ", got %"
                                B_PRId32 "\n", m_input.destination.id, destination.id));
                return;
        }

        // mark disconnected
        m_input.source = media_source::null;

        // no output? clear format:
        if(m_output.destination == media_destination::null) {
                m_format.u.raw_audio = media_raw_audio_format::wildcard;
        }

        m_input.format = m_format;

}

void FlangerNode::DisposeInputCookie(
        int32 cookie) {}

// "You should implement this function so your node will know that the data
//  format is going to change. Note that this may be called in response to
//  your AcceptFormat() call, if your AcceptFormat() call alters any wildcard
//  fields in the specified format.
//
//  Because FormatChanged() is called by the producer, you don't need to (and
//  shouldn't) ask it if the new format is acceptable.
//
//  If the format change isn't possible, return an appropriate error from
//  FormatChanged(); this error will be passed back to the producer that
//  initiated the new format negotiation in the first place."

status_t FlangerNode::FormatChanged(
        const media_source& source,
        const media_destination& destination,
        int32 changeTag,
        const media_format& newFormat) {

        // flat-out deny format changes
        return B_MEDIA_BAD_FORMAT;
}

status_t FlangerNode::GetLatencyFor(
        const media_destination& destination,
        bigtime_t* poLatency,
        media_node_id* poTimeSource) {

        PRINT(("FlangerNode::GetLatencyFor()\n"));

        // sanity check
        if(destination != m_input.destination) {
                PRINT(("\tbad destination\n"));
                return B_MEDIA_BAD_DESTINATION;
        }

        *poLatency = m_downstreamLatency + m_processingLatency;
        PRINT(("\treturning %" B_PRIdBIGTIME "\n", *poLatency));
        *poTimeSource = TimeSource()->ID();
        return B_OK;
}

status_t FlangerNode::GetNextInput(
        int32* pioCookie,
        media_input* poInput) {

        if(*pioCookie)
                return B_BAD_INDEX;

        ++*pioCookie;
        *poInput = m_input;
        return B_OK;
}

void FlangerNode::ProducerDataStatus(
        const media_destination& destination,
        int32 status,
        bigtime_t tpWhen) {

        PRINT(("FlangerNode::ProducerDataStatus()\n"));

        // sanity check
        if(destination != m_input.destination) {
                PRINT(("\tbad destination\n"));
        }

        if(m_output.destination != media_destination::null) {
                // pass status downstream
                status_t err = SendDataStatus(
                        status,
                        m_output.destination,
                        tpWhen);
                if(err < B_OK) {
                        PRINT(("\tSendDataStatus(): %s\n", strerror(err)));
                }
        }
}

// "This function is provided to aid in supporting media formats in which the
//  outer encapsulation layer doesn't supply timing information. Producers will
//  tag the buffers they generate with seek tags; these tags can be used to
//  locate key frames in the media data."

status_t FlangerNode::SeekTagRequested(
        const media_destination& destination,
        bigtime_t targetTime,
        uint32 flags,
        media_seek_tag* poSeekTag,
        bigtime_t* poTaggedTime,
        uint32* poFlags) {

        PRINT(("FlangerNode::SeekTagRequested()\n"
                "\tNot implemented.\n"));
        return B_ERROR;
}

// -------------------------------------------------------- //
// *** BBufferProducer
// -------------------------------------------------------- //

// "When a consumer calls BBufferConsumer::RequestAdditionalBuffer(), this
//  function is called as a result. Its job is to call SendBuffer() to
//  immediately send the next buffer to the consumer. The previousBufferID,
//  previousTime, and previousTag arguments identify the last buffer the
//  consumer received. Your node should respond by sending the next buffer
//  after the one described.
//
//  The previousTag may be NULL.
//  Return B_OK if all is well; otherwise return an appropriate error code."

void FlangerNode::AdditionalBufferRequested(
        const media_source& source,
        media_buffer_id previousBufferID,
        bigtime_t previousTime,
        const media_seek_tag* pPreviousTag) {

        PRINT(("FlangerNode::AdditionalBufferRequested\n"
                "\tOffline mode not implemented."));
}

void FlangerNode::Connect(
        status_t status,
        const media_source& source,
        const media_destination& destination,
        const media_format& format,
        char* pioName) {

        PRINT(("FlangerNode::Connect()\n"));
        status_t err;

        // connection failed?
        if(status < B_OK) {
                PRINT(("\tStatus: %s\n", strerror(status)));
                // 'unreserve' the output
                m_output.destination = media_destination::null;
                return;
        }

        // connection established:
        strncpy(pioName, m_output.name, B_MEDIA_NAME_LENGTH);
        m_output.destination = destination;
        m_format = format;

        // figure downstream latency
        media_node_id timeSource;
        err = FindLatencyFor(m_output.destination, &m_downstreamLatency, &timeSource);
        if(err < B_OK) {
                PRINT(("\t!!! FindLatencyFor(): %s\n", strerror(err)));
        }
        PRINT(("\tdownstream latency = %" B_PRIdBIGTIME "\n", m_downstreamLatency));

        // prepare the filter
        initFilter();

        // figure processing time
        m_processingLatency = calcProcessingLatency();
        PRINT(("\tprocessing latency = %" B_PRIdBIGTIME "\n", m_processingLatency));

        // store summed latency
        SetEventLatency(m_downstreamLatency + m_processingLatency);

        if(m_input.source != media_source::null) {
                // pass new latency upstream
                err = SendLatencyChange(
                        m_input.source,
                        m_input.destination,
                        EventLatency() + SchedulingLatency());
                if(err < B_OK)
                        PRINT(("\t!!! SendLatencyChange(): %s\n", strerror(err)));
        }

        // cache buffer duration
        SetBufferDuration(
                buffer_duration(
                        m_format.u.raw_audio));
}

void FlangerNode::Disconnect(
        const media_source& source,
        const media_destination& destination) {

        PRINT(("FlangerNode::Disconnect()\n"));

        // sanity checks
        if(source != m_output.source) {
                PRINT(("\tbad source\n"));
                return;
        }
        if(destination != m_output.destination) {
                PRINT(("\tbad destination\n"));
                return;
        }

        // clean up
        m_output.destination = media_destination::null;

        // no input? clear format:
        if(m_input.source == media_source::null) {
                m_format.u.raw_audio = media_raw_audio_format::wildcard;
        }

        m_output.format = m_format;

        // +++++ other cleanup goes here
}

status_t FlangerNode::DisposeOutputCookie(
        int32 cookie) {
        return B_OK;
}

void FlangerNode::EnableOutput(
        const media_source& source,
        bool enabled,
        int32* _deprecated_) {
        PRINT(("FlangerNode::EnableOutput()\n"));
        if(source != m_output.source) {
                PRINT(("\tbad source\n"));
                return;
        }

        m_outputEnabled = enabled;
}

status_t FlangerNode::FormatChangeRequested(
        const media_source& source,
        const media_destination& destination,
        media_format* pioFormat,
        int32* _deprecated_) {

        // deny
        PRINT(("FlangerNode::FormatChangeRequested()\n"
                "\tNot supported.\n"));

        return B_MEDIA_BAD_FORMAT;
}

status_t FlangerNode::FormatProposal(
        const media_source& source,
        media_format* pioFormat) {

        PRINT(("FlangerNode::FormatProposal()\n"));

        if(source != m_output.source) {
                PRINT(("\tbad source\n"));
                return B_MEDIA_BAD_SOURCE;
        }

        if(pioFormat->type != B_MEDIA_RAW_AUDIO) {
                PRINT(("\tbad type\n"));
                return B_MEDIA_BAD_FORMAT;
        }

        validateProposedFormat(
                (m_format.u.raw_audio.format != media_raw_audio_format::wildcard.format) ?
                        m_format :
                        m_preferredFormat,
                *pioFormat);
        return B_OK;
}

status_t FlangerNode::FormatSuggestionRequested(
        media_type type,
        int32 quality,
        media_format* poFormat) {

        PRINT(("FlangerNode::FormatSuggestionRequested()\n"));
        if(type != B_MEDIA_RAW_AUDIO) {
                PRINT(("\tbad type\n"));
                return B_MEDIA_BAD_FORMAT;
        }

        if(m_format.u.raw_audio.format != media_raw_audio_format::wildcard.format)
                *poFormat = m_format;
        else
                *poFormat = m_preferredFormat;
        return B_OK;
}

status_t FlangerNode::GetLatency(
        bigtime_t* poLatency) {

        PRINT(("FlangerNode::GetLatency()\n"));
        *poLatency = EventLatency() + SchedulingLatency();
        PRINT(("\treturning %" B_PRIdBIGTIME "\n", *poLatency));

        return B_OK;
}

status_t FlangerNode::GetNextOutput(
        int32* pioCookie,
        media_output* poOutput) {

        if(*pioCookie)
                return B_BAD_INDEX;

        ++*pioCookie;
        *poOutput = m_output;

        return B_OK;
}

// "This hook function is called when a BBufferConsumer that's receiving data
//  from you determines that its latency has changed. It will call its
//  BBufferConsumer::SendLatencyChange() function, and in response, the Media
//  Server will call your LatencyChanged() function.  The source argument
//  indicates your output that's involved in the connection, and destination
//  specifies the input on the consumer to which the connection is linked.
//  newLatency is the consumer's new latency. The flags are currently unused."
void FlangerNode::LatencyChanged(
        const media_source& source,
        const media_destination& destination,
        bigtime_t newLatency,
        uint32 flags) {

        PRINT(("FlangerNode::LatencyChanged()\n"));

        if(source != m_output.source) {
                PRINT(("\tBad source.\n"));
                return;
        }
        if(destination != m_output.destination) {
                PRINT(("\tBad destination.\n"));
                return;
        }

        m_downstreamLatency = newLatency;
        SetEventLatency(m_downstreamLatency + m_processingLatency);

        if(m_input.source != media_source::null) {
                // pass new latency upstream
                status_t err = SendLatencyChange(
                        m_input.source,
                        m_input.destination,
                        EventLatency() + SchedulingLatency());
                if(err < B_OK)
                        PRINT(("\t!!! SendLatencyChange(): %s\n", strerror(err)));
        }
}

void FlangerNode::LateNoticeReceived(
        const media_source& source,
        bigtime_t howLate,
        bigtime_t tpWhen) {

        PRINT(("FlangerNode::LateNoticeReceived()\n"
                "\thowLate == %" B_PRIdBIGTIME "\n"
                "\twhen    == %" B_PRIdBIGTIME "\n", howLate, tpWhen));

        if(source != m_output.source) {
                PRINT(("\tBad source.\n"));
                return;
        }

        if(m_input.source == media_source::null) {
                PRINT(("\t!!! No input to blame.\n"));
                return;
        }

        // +++++ check run mode?

        // pass the buck, since this node doesn't schedule buffer
        // production
        NotifyLateProducer(
                m_input.source,
                howLate,
                tpWhen);
}

// PrepareToConnect() is the second stage of format negotiations that happens
// inside BMediaRoster::Connect().  At this point, the consumer's AcceptFormat()
// method has been called, and that node has potentially changed the proposed
// format.  It may also have left wildcards in the format.  PrepareToConnect()
// *must* fully specialize the format before returning!

status_t FlangerNode::PrepareToConnect(
        const media_source& source,
        const media_destination& destination,
        media_format* pioFormat,
        media_source* poSource,
        char* poName) {

        char formatStr[256];
        string_for_format(*pioFormat, formatStr, 255);
        PRINT(("FlangerNode::PrepareToConnect()\n"
                "\tproposed format: %s\n", formatStr));

        if(source != m_output.source) {
                PRINT(("\tBad source.\n"));
                return B_MEDIA_BAD_SOURCE;
        }
        if(m_output.destination != media_destination::null) {
                PRINT(("\tAlready connected.\n"));
                return B_MEDIA_ALREADY_CONNECTED;
        }

        if(pioFormat->type != B_MEDIA_RAW_AUDIO) {
                PRINT(("\tBad format type.\n"));
                return B_MEDIA_BAD_FORMAT;
        }

        // do a final validity check:
        status_t err = validateProposedFormat(
                (m_format.u.raw_audio.format != media_raw_audio_format::wildcard.format) ?
                        m_format :
                        m_preferredFormat,
                *pioFormat);

        if(err < B_OK) {
                // no go
                return err;
        }

        // fill in wildcards
        specializeOutputFormat(*pioFormat);

        // reserve the output
        m_output.destination = destination;
        m_output.format = *pioFormat;

        // pass back source & output name
        *poSource = m_output.source;
        strncpy(poName, m_output.name, B_MEDIA_NAME_LENGTH);

        return B_OK;
}

status_t FlangerNode::SetBufferGroup(
        const media_source& source,
        BBufferGroup* pGroup) {

        PRINT(("FlangerNode::SetBufferGroup()\n"));
        if(source != m_output.source) {
                PRINT(("\tBad source.\n"));
                return B_MEDIA_BAD_SOURCE;
        }

        if(m_input.source == media_source::null) {
                PRINT(("\tNo producer to send buffers to.\n"));
                return B_ERROR;
        }

        // +++++ is this right?  buffer-group selection gets
        //       all asynchronous and weird...
        int32 changeTag;
        return SetOutputBuffersFor(
                m_input.source,
                m_input.destination,
                pGroup,
                0, &changeTag);
}

status_t FlangerNode::SetPlayRate(
        int32 numerator,
        int32 denominator) {
        // not supported
        return B_ERROR;
}

status_t FlangerNode::VideoClippingChanged(
        const media_source& source,
        int16 numShorts,
        int16* pClipData,
        const media_video_display_info& display,
        int32* poFromChangeTag) {
        // not sane
        return B_ERROR;
}

// -------------------------------------------------------- //
// *** BControllable
// -------------------------------------------------------- //

status_t FlangerNode::GetParameterValue(
        int32 id,
        bigtime_t* poLastChangeTime,
        void* poValue,
        size_t* pioSize) {

//      PRINT(("FlangerNode::GetParameterValue()\n"));

        // all parameters are floats
        if(*pioSize < sizeof(float)) {
                return B_NO_MEMORY;
        }

        *pioSize = sizeof(float);
        switch(id) {
                case P_MIX_RATIO:
                        *(float*)poValue = m_fMixRatio;
                        *poLastChangeTime = m_tpMixRatioChanged;
                        break;

                case P_SWEEP_RATE:
                        *(float*)poValue = m_fSweepRate;
                        *poLastChangeTime = m_tpSweepRateChanged;
                        break;

                case P_DELAY:
                        *(float*)poValue = m_fDelay;
                        *poLastChangeTime = m_tpDelayChanged;
                        break;

                case P_DEPTH:
                        *(float*)poValue = m_fDepth;
                        *poLastChangeTime = m_tpDepthChanged;
                        break;

                case P_FEEDBACK:
                        *(float*)poValue = m_fFeedback;
                        *poLastChangeTime = m_tpFeedbackChanged;
                        break;

                default:
                        return B_ERROR;
        }

        return B_OK;
}

void FlangerNode::SetParameterValue(
        int32 id,
        bigtime_t changeTime,
        const void* pValue,
        size_t size) {

        switch(id) {
                case P_MIX_RATIO:
                case P_SWEEP_RATE:
                case P_DELAY:
                case P_DEPTH:
                case P_FEEDBACK: {
                        if(size < sizeof(float))
                                break;

//      this is from ToneProducer.  it's fishy.
//                      if(size > sizeof(float))
//                              size = sizeof(float);

                        media_timed_event ev(
                                changeTime,
                                BTimedEventQueue::B_PARAMETER,
                                0,
                                BTimedEventQueue::B_NO_CLEANUP,
                                size,
                                id,
                                (char*)pValue, size);
                        EventQueue()->AddEvent(ev);
                        break;
                }
        }
}

// -------------------------------------------------------- //
// *** HandleEvent() impl
// -------------------------------------------------------- //

void FlangerNode::handleParameterEvent(
        const media_timed_event* pEvent) {

        float value = *(float*)pEvent->user_data;
        int32 id = pEvent->bigdata;
        size_t size = pEvent->data;
        bigtime_t now = TimeSource()->Now();

        switch(id) {
                case P_MIX_RATIO:
                        if(value == m_fMixRatio)
                                break;

                        // set
                        m_fMixRatio = value;
                        m_tpMixRatioChanged = now;
                        // broadcast
                        BroadcastNewParameterValue(
                                now,
                                id,
                                &m_fMixRatio,
                                size);
                        break;

                case P_SWEEP_RATE:
                        if(value == m_fSweepRate)
                                break;

                        // set
                        m_fSweepRate = value;
                        m_tpSweepRateChanged = now;

                        if(m_output.destination != media_destination::null) {
                                m_fThetaInc = calc_sweep_delta(
                                        m_format.u.raw_audio,
                                        m_fSweepRate);
                        }

                        // broadcast
                        BroadcastNewParameterValue(
                                now,
                                id,
                                &m_fSweepRate,
                                size);
                        break;

                case P_DELAY:
                        if(value == m_fDelay)
                                break;

                        // set
                        m_fDelay = value;
                        m_tpDelayChanged = now;

                        if(m_output.destination != media_destination::null) {
                                m_fSweepBase = calc_sweep_base(
                                        m_format.u.raw_audio,
                                        m_fDelay, m_fDepth);
                        }

                        // broadcast
                        BroadcastNewParameterValue(
                                now,
                                id,
                                &m_fDelay,
                                size);
                        break;

                case P_DEPTH:
                        if(value == m_fDepth)
                                break;

                        // set
                        m_fDepth = value;
                        m_tpDepthChanged = now;

                        if(m_output.destination != media_destination::null) {
                                m_fSweepBase = calc_sweep_base(
                                        m_format.u.raw_audio,
                                        m_fDelay, m_fDepth);
                                m_fSweepFactor = calc_sweep_factor(
                                        m_format.u.raw_audio,
                                        m_fDepth);
                        }

                        // broadcast
                        BroadcastNewParameterValue(
                                now,
                                id,
                                &m_fDepth,
                                size);
                        break;

                case P_FEEDBACK:
                        if(value == m_fFeedback)
                                break;

                        // set
                        m_fFeedback = value;
                        m_tpFeedbackChanged = now;
                        // broadcast
                        BroadcastNewParameterValue(
                                now,
                                id,
                                &m_fFeedback,
                                size);
                        break;
        }
}

void FlangerNode::handleStartEvent(
        const media_timed_event* pEvent) {
        PRINT(("FlangerNode::handleStartEvent\n"));

        startFilter();
}

void FlangerNode::handleStopEvent(
        const media_timed_event* pEvent) {
        PRINT(("FlangerNode::handleStopEvent\n"));

        stopFilter();
}

void FlangerNode::ignoreEvent(
        const media_timed_event* pEvent) {
        PRINT(("FlangerNode::ignoreEvent\n"));

}


// -------------------------------------------------------- //
// *** internal operations
// -------------------------------------------------------- //


// figure the preferred format: any fields left as wildcards
// are negotiable
void FlangerNode::getPreferredFormat(
        media_format& ioFormat) {
        ASSERT(ioFormat.type == B_MEDIA_RAW_AUDIO);

        ioFormat.u.raw_audio = media_raw_audio_format::wildcard;
        ioFormat.u.raw_audio.channel_count = 1;
        ioFormat.u.raw_audio.format = media_raw_audio_format::B_AUDIO_FLOAT;

//      ioFormat.u.raw_audio.frame_rate = 44100.0;
//      ioFormat.u.raw_audio.buffer_size = 0x1000;
}

// test the given template format against a proposed format.
// specialize wildcards for fields where the template contains
// non-wildcard data; write required fields into proposed format
// if they mismatch.
// Returns B_OK if the proposed format doesn't conflict with the
// template, or B_MEDIA_BAD_FORMAT otherwise.

status_t FlangerNode::validateProposedFormat(
        const media_format& preferredFormat,
        media_format& ioProposedFormat) {

        char formatStr[256];
        PRINT(("FlangerNode::validateProposedFormat()\n"));

        ASSERT(preferredFormat.type == B_MEDIA_RAW_AUDIO);

        string_for_format(preferredFormat, formatStr, 255);
        PRINT(("\ttemplate format: %s\n", formatStr));

        string_for_format(ioProposedFormat, formatStr, 255);
        PRINT(("\tproposed format: %s\n", formatStr));

        status_t err = B_OK;

        if(ioProposedFormat.type != B_MEDIA_RAW_AUDIO) {
                // out of the ballpark
                ioProposedFormat = preferredFormat;
                return B_MEDIA_BAD_FORMAT;
        }

        // wildcard format
        media_raw_audio_format& wild = media_raw_audio_format::wildcard;
        // proposed format
        media_raw_audio_format& f = ioProposedFormat.u.raw_audio;
        // template format
        const media_raw_audio_format& pref = preferredFormat.u.raw_audio;

        if(pref.frame_rate != wild.frame_rate) {
                if(f.frame_rate != pref.frame_rate) {
                        if(f.frame_rate != wild.frame_rate)
                                err = B_MEDIA_BAD_FORMAT;
                        f.frame_rate = pref.frame_rate;
                }
        }

        if(pref.channel_count != wild.channel_count) {
                if(f.channel_count != pref.channel_count) {
                        if(f.channel_count != wild.channel_count)
                                err = B_MEDIA_BAD_FORMAT;
                        f.channel_count = pref.channel_count;
                }
        }

        if(pref.format != wild.format) {
                if(f.format != pref.format) {
                        if(f.format != wild.format)
                                err = B_MEDIA_BAD_FORMAT;
                        f.format = pref.format;
                }
        }

        if(pref.byte_order != wild.byte_order) {
                if(f.byte_order != pref.byte_order) {
                        if(f.byte_order != wild.byte_order)
                                err = B_MEDIA_BAD_FORMAT;
                        f.byte_order = pref.byte_order;
                }
        }

        if(pref.buffer_size != wild.buffer_size) {
                if(f.buffer_size != pref.buffer_size) {
                        if(f.buffer_size != wild.buffer_size)
                                err = B_MEDIA_BAD_FORMAT;
                        f.buffer_size = pref.buffer_size;
                }
        }

        if(err != B_OK) {
                string_for_format(ioProposedFormat, formatStr, 255);
                PRINT((
                        "\tformat conflict; suggesting:\n\tformat %s\n", formatStr));
        }

        return err;
}

// fill in wildcards in the given format.
// (assumes the format passes validateProposedFormat().)
void FlangerNode::specializeOutputFormat(
        media_format& ioFormat) {

        char formatStr[256];
        string_for_format(ioFormat, formatStr, 255);
        PRINT(("FlangerNode::specializeOutputFormat()\n"
                "\tinput format: %s\n", formatStr));

        ASSERT(ioFormat.type == B_MEDIA_RAW_AUDIO);

        // carpal_tunnel_paranoia
        media_raw_audio_format& f = ioFormat.u.raw_audio;
        media_raw_audio_format& w = media_raw_audio_format::wildcard;

        if (f.frame_rate == w.frame_rate)
                f.frame_rate = 44100.0;
        if (f.channel_count == w.channel_count) {
                //+++++ tweaked 15sep99
                if (m_input.source != media_source::null)
                        f.channel_count = m_input.format.u.raw_audio.channel_count;
                else
                        f.channel_count = 1;
        }
        if (f.format == w.format)
                f.format = media_raw_audio_format::B_AUDIO_FLOAT;
        if (f.byte_order == w.byte_order)
                f.byte_order = (B_HOST_IS_BENDIAN) ? B_MEDIA_BIG_ENDIAN : B_MEDIA_LITTLE_ENDIAN;
        if (f.buffer_size == w.buffer_size)
                f.buffer_size = 2048;

        string_for_format(ioFormat, formatStr, 255);
        PRINT(("\toutput format: %s\n", formatStr));
}

// set parameters to their default settings
void FlangerNode::initParameterValues() {
        m_fMixRatio = 0.5;
        m_tpMixRatioChanged = 0LL;

        m_fSweepRate = 0.1;
        m_tpSweepRateChanged = 0LL;

        m_fDelay = 10.0;
        m_tpDelayChanged = 0LL;

        m_fDepth = 25.0;
        m_tpDepthChanged = 0LL;

        m_fFeedback = 0.1;
        m_tpFeedbackChanged = 0LL;
}

// create and register a parameter web
void FlangerNode::initParameterWeb() {
        BParameterWeb* pWeb = new BParameterWeb();
        BParameterGroup* pTopGroup = pWeb->MakeGroup("FlangerNode Parameters");

        BNullParameter* label;
        BContinuousParameter* value;
        BParameterGroup* g;

        // mix ratio
        g = pTopGroup->MakeGroup("Mix ratio");
        label = g->MakeNullParameter(
                P_MIX_RATIO_LABEL,
                B_MEDIA_NO_TYPE,
                "Mix ratio",
                B_GENERIC);

        value = g->MakeContinuousParameter(
                P_MIX_RATIO,
                B_MEDIA_NO_TYPE,
                "",
                B_GAIN, "", 0.0, 1.0, 0.05);
        label->AddOutput(value);
        value->AddInput(label);

        // sweep rate
        g = pTopGroup->MakeGroup("Sweep rate");
        label = g->MakeNullParameter(
                P_SWEEP_RATE_LABEL,
                B_MEDIA_NO_TYPE,
                "Sweep rate",
                B_GENERIC);

        value = g->MakeContinuousParameter(
                P_SWEEP_RATE,
                B_MEDIA_NO_TYPE,
                "",
                B_GAIN, "Hz", 0.01, 10.0, 0.01);
        label->AddOutput(value);
        value->AddInput(label);

        // sweep range: minimum delay
        g = pTopGroup->MakeGroup("Delay");
        label = g->MakeNullParameter(
                P_DELAY_LABEL,
                B_MEDIA_NO_TYPE,
                "Delay",
                B_GENERIC);

        value = g->MakeContinuousParameter(
                P_DELAY,
                B_MEDIA_NO_TYPE,
                "",
                B_GAIN, "ms", 0.1, s_fMaxDelay/2.0, 0.1);
        label->AddOutput(value);
        value->AddInput(label);

        // sweep range: maximum
        g = pTopGroup->MakeGroup("Depth");
        label = g->MakeNullParameter(
                P_DEPTH_LABEL,
                B_MEDIA_NO_TYPE,
                "Depth",
                B_GENERIC);

        value = g->MakeContinuousParameter(
                P_DEPTH,
                B_MEDIA_NO_TYPE,
                "",
                B_GAIN, "ms", 1.0, s_fMaxDelay/4.0, 0.1);
        label->AddOutput(value);
        value->AddInput(label);

        // feedback
        g = pTopGroup->MakeGroup("Feedback");
        label = g->MakeNullParameter(
                P_FEEDBACK_LABEL,
                B_MEDIA_NO_TYPE,
                "Feedback",
                B_GENERIC);

        value = g->MakeContinuousParameter(
                P_FEEDBACK,
                B_MEDIA_NO_TYPE,
                "",
                B_GAIN, "", 0.0, 1.0, 0.01);
        label->AddOutput(value);
        value->AddInput(label);

        // * Install parameter web
        SetParameterWeb(pWeb);
}

// construct delay line if necessary, reset filter state
void FlangerNode::initFilter() {
        PRINT(("FlangerNode::initFilter()\n"));
        ASSERT(m_format.u.raw_audio.format != media_raw_audio_format::wildcard.format);

        if(!m_pDelayBuffer) {
                m_pDelayBuffer = new AudioBuffer(
                        m_format.u.raw_audio,
                        frames_for_duration(
                                m_format.u.raw_audio,
                                (bigtime_t)s_fMaxDelay*1000LL));
                m_pDelayBuffer->zero();
        }

        m_framesSent = 0;
        m_delayWriteFrame = 0;
        m_fTheta = 0.0;
        m_fThetaInc = calc_sweep_delta(m_format.u.raw_audio, m_fSweepRate);
        m_fSweepBase = calc_sweep_base(m_format.u.raw_audio, m_fDelay, m_fDepth);
        m_fSweepFactor = calc_sweep_factor(m_format.u.raw_audio, m_fDepth);

//
//      PRINT((
//              "\tFrames       %ld\n"
//              "\tDelay        %.2f\n"
//              "\tDepth        %.2f\n"
//              "\tSweepBase    %.2f\n"
//              "\tSweepFactor  %.2f\n",
//              m_pDelayBuffer->frames(),
//              m_fDelay, m_fDepth, m_fSweepBase, m_fSweepFactor));
}

void FlangerNode::startFilter() {
        PRINT(("FlangerNode::startFilter()\n"));
}
void FlangerNode::stopFilter() {
        PRINT(("FlangerNode::stopFilter()\n"));
}

// figure processing latency by doing 'dry runs' of filterBuffer()
bigtime_t FlangerNode::calcProcessingLatency() {
        PRINT(("FlangerNode::calcProcessingLatency()\n"));

        if(m_output.destination == media_destination::null) {
                PRINT(("\tNot connected.\n"));
                return 0LL;
        }

        // allocate a temporary buffer group
        BBufferGroup* pTestGroup = new BBufferGroup(
                m_output.format.u.raw_audio.buffer_size, 1);

        // fetch a buffer
        BBuffer* pBuffer = pTestGroup->RequestBuffer(
                m_output.format.u.raw_audio.buffer_size);
        ASSERT(pBuffer);

        pBuffer->Header()->type = B_MEDIA_RAW_AUDIO;
        pBuffer->Header()->size_used = m_output.format.u.raw_audio.buffer_size;

        // run the test
        bigtime_t preTest = system_time();
        filterBuffer(pBuffer);
        bigtime_t elapsed = system_time()-preTest;

        // clean up
        pBuffer->Recycle();
        delete pTestGroup;

        // reset filter state
        initFilter();

        return elapsed;
}

// filter buffer data in place
//
// +++++ add 2-channel support 15sep991
//

const size_t MAX_CHANNELS = 2;

struct _frame {
        float channel[MAX_CHANNELS];
};

void FlangerNode::filterBuffer(
        BBuffer* pBuffer) {

        if(!m_pDelayBuffer)
                return;

        // for each input frame:
        // - fetch
        // - write delay line(writeFrame)
        // - read delay line(writeFrame-readOffset)  [interpolate]
        // - mix (replace)
        // - advance writeFrame
        // - update readOffset

        AudioBuffer input(m_format.u.raw_audio, pBuffer);

        ASSERT(
                m_format.u.raw_audio.channel_count == 1 ||
                m_format.u.raw_audio.channel_count == 2);
        uint32 channels = m_format.u.raw_audio.channel_count;
        bool stereo = m_format.u.raw_audio.channel_count == 2;

        uint32 samples = input.frames() * channels;
        for(uint32 inPos = 0; inPos < samples; ++inPos) {

                // read from input buffer
                _frame inFrame = {};
                inFrame.channel[0] = ((float*)input.data())[inPos];
                if(stereo)
                        inFrame.channel[1] = ((float*)input.data())[inPos + 1];

                // interpolate from delay buffer
                float readOffset = m_fSweepBase + (m_fSweepFactor * sin(m_fTheta));
                float fReadFrame = (float)m_delayWriteFrame - readOffset;
                if(fReadFrame < 0.0)
                        fReadFrame += m_pDelayBuffer->frames();

//              float delayed;


                // read low-index (possibly only) frame
                _frame delayedFrame = {};

                int32 readFrameLo = (int32)floor(fReadFrame);
                uint32 pos = readFrameLo * channels;
                delayedFrame.channel[0] = ((float*)m_pDelayBuffer->data())[pos];
                if(stereo)
                        delayedFrame.channel[1] = ((float*)m_pDelayBuffer->data())[pos+1];

                if(readFrameLo != (int32)fReadFrame) {

                        // interpolate (A)
                        uint32 readFrameHi = (int32)ceil(fReadFrame);
                        delayedFrame.channel[0] *= ((float)readFrameHi - fReadFrame);
                        if(stereo)
                                delayedFrame.channel[1] *= ((float)readFrameHi - fReadFrame);

                        // read high-index frame
                        int32 hiWrap = (readFrameHi == m_pDelayBuffer->frames()) ? 0 : readFrameHi;
                        ASSERT(hiWrap >= 0);
                        pos = (uint32)hiWrap * channels;
                        _frame hiFrame;
                        hiFrame.channel[0] = ((float*)m_pDelayBuffer->data())[pos];
                        if(stereo)
                                hiFrame.channel[1] = ((float*)m_pDelayBuffer->data())[pos+1];

                        // interpolate (B)
                        delayedFrame.channel[0] +=
                                hiFrame.channel[0] * (fReadFrame - (float)readFrameLo);
                        if(stereo)
                                delayedFrame.channel[1] +=
                                        hiFrame.channel[1] * (fReadFrame - (float)readFrameLo);
                }

                // mix back to output buffer
                ((float*)input.data())[inPos] =
                        (inFrame.channel[0] * (1.0-m_fMixRatio)) +
                        (delayedFrame.channel[0] * m_fMixRatio);
                if(stereo)
                        ((float*)input.data())[inPos+1] =
                                (inFrame.channel[1] * (1.0-m_fMixRatio)) +
                                (delayedFrame.channel[1] * m_fMixRatio);

                // write to delay buffer
                uint32 delayWritePos = m_delayWriteFrame * channels;
                ((float*)m_pDelayBuffer->data())[delayWritePos] =
                        inFrame.channel[0] +
                        (delayedFrame.channel[0] * m_fFeedback);
                if(stereo)
                        ((float*)m_pDelayBuffer->data())[delayWritePos+1] =
                                inFrame.channel[1] +
                                (delayedFrame.channel[1] * m_fFeedback);

                // advance write position
                if(++m_delayWriteFrame >= m_pDelayBuffer->frames())
                        m_delayWriteFrame = 0;

                // advance read offset ('LFO')
                m_fTheta += m_fThetaInc;
                if(m_fTheta > 2 * M_PI)
                        m_fTheta -= 2 * M_PI;

//              if(m_fDelayReadDelta < 0.0) {
//                      if(m_fDelayReadOffset < m_fDelay)
//                              m_fDelayReadDelta = -m_fDelayReadDelta;
//              } else {
//                      if(m_fDelayReadOffset > m_fDepth)
//                              m_fDelayReadDelta = -m_fDelayReadDelta;
//              }
//              m_fDelayReadOffset += m_fDelayReadDelta;
        }
}


/*!     Figure the rate at which the (radial) read offset changes,
        based on the given sweep rate (in Hz)
*/
float
calc_sweep_delta(const media_raw_audio_format& format, float fRate)
{
        return 2 * M_PI * fRate / format.frame_rate;
}

/*!     Figure the base delay (in frames) based on the given
        sweep delay/depth (in msec)
*/
float
calc_sweep_base(const media_raw_audio_format& format, float delay, float depth)
{
        return (format.frame_rate * (delay + depth)) / 1000.0;
}


float
calc_sweep_factor(const media_raw_audio_format& format, float depth)
{
        return (format.frame_rate * depth) / 1000.0;
}


// END -- FlangerNode.cpp --