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/*************************************************************************** |
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* * |
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* LinuxSampler - modular, streaming capable sampler * |
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* * |
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* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * |
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* Copyright (C) 2005 - 2009 Christian Schoenebeck * |
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* Copyright (C) 2009 Grigor Iliev * |
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* * |
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* This program is free software; you can redistribute it and/or modify * |
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* it under the terms of the GNU General Public License as published by * |
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* the Free Software Foundation; either version 2 of the License, or * |
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* (at your option) any later version. * |
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* * |
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* This program is distributed in the hope that it will be useful, * |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of * |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
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* GNU General Public License for more details. * |
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* * |
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* You should have received a copy of the GNU General Public License * |
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* along with this program; if not, write to the Free Software * |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, * |
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* MA 02111-1307 USA * |
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***************************************************************************/ |
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|
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#ifndef __LS_STREAMBASE_H__ |
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#define __LS_STREAMBASE_H__ |
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|
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#include "Stream.h" |
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#include "../../common/global.h" |
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#include "../../common/RingBuffer.h" |
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#include <iostream> |
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|
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namespace LinuxSampler { |
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|
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/** @brief Buffered Disk Stream |
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* |
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* This encapsulation of a disk stream uses a ring buffer to allow |
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* thread safe refilling the stream's buffer with one thread (disk |
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* thread) and actual use / extraction of the audio data from the |
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* stream's buffer with another thread (audio thread). |
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*/ |
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template <class R> |
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class StreamBase : public Stream { |
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public: |
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// Methods |
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StreamBase(uint BufferSize, uint BufferWrapElements) : Stream(BufferSize, BufferWrapElements) { |
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this->pRegion = NULL; |
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this->SampleOffset = 0; |
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} |
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|
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virtual ~StreamBase() { |
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Reset(); |
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if (pRingBuffer) delete pRingBuffer; |
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UnusedStreams--; |
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TotalStreams--; |
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} |
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|
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/// Returns number of refilled sample points or a value < 0 on error. |
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virtual int ReadAhead(unsigned long SampleCount) { |
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if (this->State == state_unused) return -1; |
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if (this->State == state_end) return 0; |
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if (!SampleCount) return 0; |
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if (!pRingBuffer->write_space()) return 0; |
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|
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long samplestoread = SampleCount / SampleInfo.ChannelsPerFrame; |
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uint8_t* pBuf = pRingBuffer->get_write_ptr(); |
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long total_readsamples = Read(pBuf, samplestoread); |
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|
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// we must delay the increment_write_ptr_with_wrap() after the while() loop because we need to |
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// ensure that we read exactly SampleCount sample, otherwise the buffer wrapping code will fail |
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pRingBuffer->increment_write_ptr_with_wrap(total_readsamples * SampleInfo.FrameSize); |
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|
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return total_readsamples; |
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} |
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|
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virtual void WriteSilence(unsigned long SilenceSampleWords) { |
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memset(pRingBuffer->get_write_ptr(), 0, SilenceSampleWords * SampleInfo.BytesPerSample); |
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pRingBuffer->increment_write_ptr_with_wrap(SilenceSampleWords * SampleInfo.BytesPerSample); |
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} |
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|
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/// Called by disk thread to activate the disk stream. |
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void Launch ( |
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Stream::Handle hStream, |
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reference_t* pExportReference, |
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R* pRgn, |
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SampleDescription SampleInfo, |
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Sample::PlaybackState PlaybackState, |
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unsigned long SampleOffset, |
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bool DoLoop |
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) { |
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UnusedStreams--; |
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this->pExportReference = pExportReference; |
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this->hThis = hStream; |
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this->pRegion = pRgn; |
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this->SampleInfo = SampleInfo; |
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this->PlaybackState = PlaybackState; |
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this->SampleOffset = SampleOffset; |
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this->DoLoop = DoLoop; |
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SetState(state_active); |
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} |
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|
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protected: |
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// Attributes |
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unsigned long SampleOffset; |
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R* pRegion; |
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bool DoLoop; |
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|
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virtual void Reset() { |
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SampleOffset = 0; |
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pRegion = NULL; |
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PlaybackState.position = 0; |
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PlaybackState.reverse = false; |
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hThis = 0; |
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pRingBuffer->init(); // reset ringbuffer |
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if (State != state_unused) { |
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// we can't do 'SetPos(state_unused)' here, due to possible race conditions) |
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if (pExportReference) { |
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pExportReference->State = state_unused; |
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pExportReference = NULL; |
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} |
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State = state_unused; |
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UnusedStreams++; |
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} |
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} |
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|
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private: |
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|
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// Methods |
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|
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}; |
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} // namespace LinuxSampler |
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|
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#endif // __LS_STREAMBASE_H__ |