engines/gig/Stream.h

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *   Copyright (C) 2005 - 2007 Christian Schoenebeck                       *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#ifndef __LS_GIG_STREAM_H__
#define __LS_GIG_STREAM_H__

#include "../../common/global.h"

#include <gig.h>

#include "../../common/RingBuffer.h"

namespace LinuxSampler { namespace gig {

    /** @brief Buffered Disk Stream
     *
     * This encapsulation of a disk stream uses a ring buffer to allow
     * thread safe refilling the stream's buffer with one thread (disk
     * thread) and actual use / extraction of the audio data from the
     * stream's buffer with another thread (audio thread).
     */
    class Stream {
        public:
            // Member Types
            typedef uint32_t OrderID_t;
            typedef uint32_t Handle; ///< unique identifier of a relationship between one stream and a consumer (Voice)
            enum { INVALID_HANDLE = 0 };
            enum state_t {           ///< streams go through severe cyclic state transition (unused->active->end->unused->...)
                state_unused,        ///< stream is not in use, thus can still be launched
                state_active,        ///< stream provides data in it's buffer to be read and hasn't reached the end yet (this is the usual case)
                state_end            ///< stream end reached but still providing data in it's buffer to be read (after the client read all remaining data from the stream buffer, state will change automatically to state_unused)
            };
            struct reference_t {     ///< Defines the current relationship between the stream and a client (voice).
                OrderID_t OrderID;   ///< Unique identifier that identifies the creation order of a stream requested by a voice.
                Handle    hStream;   ///< Unique identifier of the relationship between stream and client.
                state_t   State;     ///< Current state of the stream that will be pretended to the client (the actual state of the stream might differ though, because the stream might already be in use by another client).
                Stream*   pStream;   ///< Points to the assigned and activated stream or is NULL if the disk thread hasn't launched a stream yet.
            };

            // Methods
            Stream( ::gig::buffer_t* pDecompressionBuffer, uint BufferSize, uint BufferWrapElements);
            virtual ~Stream();
            int  ReadAhead(unsigned long SampleCount);
            void WriteSilence(unsigned long SilenceSampleWords);

            inline int GetReadSpace() {
                return (pRingBuffer && State != state_unused) ? pRingBuffer->read_space() / BytesPerSample : 0;
            }

            inline int GetWriteSpace() {
                return (pRingBuffer && State == state_active) ? pRingBuffer->write_space() / BytesPerSample : 0;
            }

            inline int GetWriteSpaceToEnd() {
                return (pRingBuffer && State == state_active) ? pRingBuffer->write_space_to_end_with_wrap() / BytesPerSample : 0;
            }

            // adjusts the write space to avoid buffer boundaries which would lead to the wrap space
            // within the buffer (needed for interpolation) getting filled only partially
            // for more infos see the docs in ringbuffer.h at adjust_write_space_to_avoid_boundary()
            inline int AdjustWriteSpaceToAvoidBoundary(int cnt, int capped_cnt) {
              return pRingBuffer->adjust_write_space_to_avoid_boundary(cnt * BytesPerSample, capped_cnt * BytesPerSample) / BytesPerSample;
            }

            // gets the current read_ptr within the ringbuffer
            inline uint8_t* GetReadPtr(void) {
                return pRingBuffer->get_read_ptr();
            }

            inline void IncrementReadPos(uint Count)  {
                Count *= BytesPerSample;
                uint leftspace = pRingBuffer->read_space();
                pRingBuffer->increment_read_ptr(Min(Count, leftspace));
                if (State == state_end && Count >= leftspace) {
                    Reset(); // quit relation between consumer (voice) and stream and reset stream right after
                }
            }

            // Static Method
            inline static uint       GetUnusedStreams() { return UnusedStreams; }
        protected:
            // Methods
            void                     Launch(Stream::Handle hStream, reference_t* pExportReference, ::gig::DimensionRegion* pDimRgn, unsigned long SampleOffset, bool DoLoop);
            inline void              Kill()      { pExportReference = NULL; Reset(); } ///< Will be called by disk thread after a 'deletion' command from the audio thread (within the voice class)
            inline Stream::Handle    GetHandle() { return hThis; }
            inline Stream::state_t   GetState()  { return State; }
            friend class DiskThread; // only the disk thread should be able to launch and most important kill a disk stream to avoid race conditions
        private:
            // Attributes
            reference_t*             pExportReference;
            state_t                  State;
            Stream::Handle           hThis;
            unsigned long            SampleOffset;
            ::gig::DimensionRegion*  pDimRgn;
            ::gig::playback_state_t  PlaybackState;
            RingBuffer<uint8_t,false>* pRingBuffer;
            bool                     DoLoop;
            ::gig::buffer_t*         pDecompressionBuffer;
            int                      BytesPerSample;

            // Static Attributes
            static uint              UnusedStreams; //< Reflects how many stream objects of all stream instances are currently not in use.
            static uint              TotalStreams; //< Reflects how many stream objects currently exist.

            // Methods
            inline void Reset() {
                SampleOffset                   = 0;
                pDimRgn                        = NULL;
                PlaybackState.position         = 0;
                PlaybackState.reverse          = false;
                hThis                          = 0;
                pRingBuffer->init(); // reset ringbuffer
                if (State != state_unused) {
                    // we can't do 'SetPos(state_unused)' here, due to possible race conditions)
                    if (pExportReference) {
                        pExportReference->State = state_unused;
                        pExportReference        = NULL;
                    }
                    State = state_unused;
                    UnusedStreams++;
                }
            }
            inline void SetState(state_t State) {
                if (pExportReference) pExportReference->State = State;
                this->State = State;
            }
            inline long Min(long a, long b) { return (a < b) ? a : b; }
    };

}} // namespace LinuxSampler::gig

#endif // __LS_GIG_STREAM_H__
1	schoenebeck	53	/***************************************************************************
2			* *
3			* LinuxSampler - modular, streaming capable sampler *
4			* *
5	schoenebeck	56	* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck *
6	schoenebeck	1321	* Copyright (C) 2005 - 2007 Christian Schoenebeck *
7	schoenebeck	53	* *
8			* This program is free software; you can redistribute it and/or modify *
9			* it under the terms of the GNU General Public License as published by *
10			* the Free Software Foundation; either version 2 of the License, or *
11			* (at your option) any later version. *
12			* *
13			* This program is distributed in the hope that it will be useful, *
14			* but WITHOUT ANY WARRANTY; without even the implied warranty of *
15			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16			* GNU General Public License for more details. *
17			* *
18			* You should have received a copy of the GNU General Public License *
19			* along with this program; if not, write to the Free Software *
20			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
21			* MA 02111-1307 USA *
22			***************************************************************************/
23
24			#ifndef __LS_GIG_STREAM_H__
25			#define __LS_GIG_STREAM_H__
26
27			#include "../../common/global.h"
28
29	schoenebeck	505	#include <gig.h>
30
31	schoenebeck	53	#include "../../common/RingBuffer.h"
32
33			namespace LinuxSampler { namespace gig {
34
35	schoenebeck	563	/** @brief Buffered Disk Stream
36			*
37			* This encapsulation of a disk stream uses a ring buffer to allow
38			* thread safe refilling the stream's buffer with one thread (disk
39			* thread) and actual use / extraction of the audio data from the
40			* stream's buffer with another thread (audio thread).
41			*/
42	schoenebeck	53	class Stream {
43			public:
44			// Member Types
45			typedef uint32_t OrderID_t;
46			typedef uint32_t Handle; ///< unique identifier of a relationship between one stream and a consumer (Voice)
47	schoenebeck	1321	enum { INVALID_HANDLE = 0 };
48	schoenebeck	53	enum state_t { ///< streams go through severe cyclic state transition (unused->active->end->unused->...)
49			state_unused, ///< stream is not in use, thus can still be launched
50			state_active, ///< stream provides data in it's buffer to be read and hasn't reached the end yet (this is the usual case)
51			state_end ///< stream end reached but still providing data in it's buffer to be read (after the client read all remaining data from the stream buffer, state will change automatically to state_unused)
52			};
53			struct reference_t { ///< Defines the current relationship between the stream and a client (voice).
54			OrderID_t OrderID; ///< Unique identifier that identifies the creation order of a stream requested by a voice.
55			Handle hStream; ///< Unique identifier of the relationship between stream and client.
56			state_t State; ///< Current state of the stream that will be pretended to the client (the actual state of the stream might differ though, because the stream might already be in use by another client).
57			Stream* pStream; ///< Points to the assigned and activated stream or is NULL if the disk thread hasn't launched a stream yet.
58			};
59
60			// Methods
61	schoenebeck	385	Stream( ::gig::buffer_t* pDecompressionBuffer, uint BufferSize, uint BufferWrapElements);
62	letz	502	virtual ~Stream();
63	schoenebeck	53	int ReadAhead(unsigned long SampleCount);
64			void WriteSilence(unsigned long SilenceSampleWords);
65
66			inline int GetReadSpace() {
67	persson	903	return (pRingBuffer && State != state_unused) ? pRingBuffer->read_space() / BytesPerSample : 0;
68	schoenebeck	53	}
69
70			inline int GetWriteSpace() {
71	senoner	1484	return (pRingBuffer && State == state_active) ? pRingBuffer->write_space() / BytesPerSample : 0;
72	schoenebeck	53	}
73
74			inline int GetWriteSpaceToEnd() {
75	persson	903	return (pRingBuffer && State == state_active) ? pRingBuffer->write_space_to_end_with_wrap() / BytesPerSample : 0;
76	schoenebeck	53	}
77
78			// adjusts the write space to avoid buffer boundaries which would lead to the wrap space
79			// within the buffer (needed for interpolation) getting filled only partially
80			// for more infos see the docs in ringbuffer.h at adjust_write_space_to_avoid_boundary()
81			inline int AdjustWriteSpaceToAvoidBoundary(int cnt, int capped_cnt) {
82	persson	903	return pRingBuffer->adjust_write_space_to_avoid_boundary(cnt * BytesPerSample, capped_cnt * BytesPerSample) / BytesPerSample;
83	schoenebeck	53	}
84
85			// gets the current read_ptr within the ringbuffer
86	persson	903	inline uint8_t* GetReadPtr(void) {
87	schoenebeck	53	return pRingBuffer->get_read_ptr();
88			}
89
90			inline void IncrementReadPos(uint Count) {
91	persson	903	Count *= BytesPerSample;
92	schoenebeck	53	uint leftspace = pRingBuffer->read_space();
93			pRingBuffer->increment_read_ptr(Min(Count, leftspace));
94			if (State == state_end && Count >= leftspace) {
95			Reset(); // quit relation between consumer (voice) and stream and reset stream right after
96			}
97			}
98
99			// Static Method
100			inline static uint GetUnusedStreams() { return UnusedStreams; }
101			protected:
102			// Methods
103	persson	865	void Launch(Stream::Handle hStream, reference_t* pExportReference, ::gig::DimensionRegion* pDimRgn, unsigned long SampleOffset, bool DoLoop);
104	schoenebeck	53	inline void Kill() { pExportReference = NULL; Reset(); } ///< Will be called by disk thread after a 'deletion' command from the audio thread (within the voice class)
105			inline Stream::Handle GetHandle() { return hThis; }
106			inline Stream::state_t GetState() { return State; }
107			friend class DiskThread; // only the disk thread should be able to launch and most important kill a disk stream to avoid race conditions
108			private:
109			// Attributes
110			reference_t* pExportReference;
111			state_t State;
112			Stream::Handle hThis;
113			unsigned long SampleOffset;
114	persson	865	::gig::DimensionRegion* pDimRgn;
115	schoenebeck	53	::gig::playback_state_t PlaybackState;
116	schoenebeck	970	RingBuffer<uint8_t,false>* pRingBuffer;
117	schoenebeck	53	bool DoLoop;
118	schoenebeck	385	::gig::buffer_t* pDecompressionBuffer;
119	persson	903	int BytesPerSample;
120	schoenebeck	53
121			// Static Attributes
122			static uint UnusedStreams; //< Reflects how many stream objects of all stream instances are currently not in use.
123	senkov	333	static uint TotalStreams; //< Reflects how many stream objects currently exist.
124	schoenebeck	53
125			// Methods
126			inline void Reset() {
127			SampleOffset = 0;
128	persson	865	pDimRgn = NULL;
129	schoenebeck	53	PlaybackState.position = 0;
130			PlaybackState.reverse = false;
131			hThis = 0;
132			pRingBuffer->init(); // reset ringbuffer
133			if (State != state_unused) {
134			// we can't do 'SetPos(state_unused)' here, due to possible race conditions)
135			if (pExportReference) {
136			pExportReference->State = state_unused;
137			pExportReference = NULL;
138			}
139			State = state_unused;
140			UnusedStreams++;
141			}
142			}
143			inline void SetState(state_t State) {
144			if (pExportReference) pExportReference->State = State;
145			this->State = State;
146			}
147			inline long Min(long a, long b) { return (a < b) ? a : b; }
148			};
149
150			}} // namespace LinuxSampler::gig
151
152			#endif // __LS_GIG_STREAM_H__