trunk/src/diskthread.cpp

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003 by Benno Senoner                                   *
 *                                                                         *
 *   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                                                   *
 ***************************************************************************/

#include "diskthread.h"


// *********** DiskThread **************
// *


// just a placeholder to mark a cell in the pickup array as 'reserved'
Stream* DiskThread::SLOT_RESERVED = (Stream*) &SLOT_RESERVED;


// #########################################################################
// # Foreign Thread Section
// #         (following code intended to be interface for audio thread)


/**
 * Suspend disk thread, kill all active streams, clear all queues and the
 * pickup array and reset all streams. Call this method to bring everything
 * in the disk thread to day one. If the disk thread was running, it will be
 * respawned right after everything was reset.
 */
void DiskThread::Reset() {
    bool running = this->IsRunning();
    if (running) this->StopThread();
    for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
        pStreams[i]->Kill();
    }
    for (int i = 1; i <= MAX_INPUT_STREAMS; i++) {
        pCreatedStreams[i] = NULL;
    }
    GhostQueue->init();
    CreationQueue->init();
    DeletionQueue->init();
    ActiveStreamCount = 0;
    ActiveStreamCountMax = 0;
    if (running) this->StartThread(); // start thread only if it was running before
}

String DiskThread::GetBufferFillBytes() {
    bool activestreams = false;
    std::stringstream ss;
    for (uint i = 0; i < this->Streams; i++) {
        if (pStreams[i]->GetState() == Stream::state_unused) continue;
        uint bufferfill = pStreams[i]->GetReadSpace() * sizeof(sample_t);
        uint streamid   = (uint) pStreams[i]->GetHandle();
        if (!streamid) continue;

        if (activestreams) ss << ",[" << streamid << ']' << bufferfill;
        else {
            ss << '[' << streamid << ']' << bufferfill;
            activestreams = true;
        }
    }
    return ss.str();
}

String DiskThread::GetBufferFillPercentage() {
    bool activestreams = false;
    std::stringstream ss;
    for (uint i = 0; i < this->Streams; i++) {
        if (pStreams[i]->GetState() == Stream::state_unused) continue;
        uint bufferfill = (uint) ((float) pStreams[i]->GetReadSpace() / (float) STREAM_BUFFER_SIZE * 100);
        uint streamid   = (uint) pStreams[i]->GetHandle();
        if (!streamid) continue;

        if (activestreams) ss << ",[" << streamid << ']' << bufferfill << '%';
        else {
            ss << '[' << streamid << ']' << bufferfill;
            activestreams = true;
        }
    }
    return ss.str();
}

/**
 * Returns -1 if command queue or pickup pool is full, 0 on success (will be
 * called by audio thread within the voice class).
 */
int DiskThread::OrderNewStream(Stream::reference_t* pStreamRef, gig::Sample* pSample, unsigned long SampleOffset, bool DoLoop) {
    dmsg(4,("Disk Thread: new stream ordered\n"));
    if (CreationQueue->write_space() < 1) {
        dmsg(1,("DiskThread: Order queue full!\n"));
        return -1;
    }

    pStreamRef->State   = Stream::state_active;
    pStreamRef->OrderID = CreateOrderID();
    pStreamRef->hStream = CreateHandle();
    pStreamRef->pStream = NULL; // a stream has to be activated by the disk thread first

    if (!pStreamRef->OrderID) return -1; // there was no free slot

    create_command_t cmd;
    cmd.OrderID      = pStreamRef->OrderID;
    cmd.hStream      = pStreamRef->hStream;
    cmd.pStreamRef   = pStreamRef;
    cmd.pSample      = pSample;
    cmd.SampleOffset = SampleOffset;
    cmd.DoLoop       = DoLoop;

    CreationQueue->push(&cmd);
    return 0;
}

/**
 * Returns -1 if command queue is full, 0 on success (will be called by audio
 * thread within the voice class).
 */
int DiskThread::OrderDeletionOfStream(Stream::reference_t* pStreamRef) {
    dmsg(4,("Disk Thread: stream deletion ordered\n"));
    if (DeletionQueue->write_space() < 1) {
        dmsg(1,("DiskThread: Deletion queue full!\n"));
        return -1;
    }

    delete_command_t cmd;
    cmd.pStream = pStreamRef->pStream;
    cmd.hStream = pStreamRef->hStream;
    cmd.OrderID = pStreamRef->OrderID;

    DeletionQueue->push(&cmd);
    return 0;
}

/**
 * Returns the pointer to a disk stream if the ordered disk stream
 * represented by the \a StreamOrderID was already activated by the disk
 * thread, returns NULL otherwise. If the call was successful, thus if it
 * returned a valid stream pointer, the caller has to the store that pointer
 * by himself, because it's not possible to call this method again with the
 * same used order ID; this method is just intended for picking up an ordered
 * disk stream. This method will usually be called by the voice class (within
 * the audio thread).
 *
 * @param StreamOrderID - ID previously returned by OrderNewStream()
 * @returns               pointer to created stream object, NULL otherwise
 */
Stream* DiskThread::AskForCreatedStream(Stream::OrderID_t StreamOrderID) {
    dmsg(4,("Disk Thread: been asked if stream already created, OrderID=%x ", StreamOrderID));
    Stream* pStream = pCreatedStreams[StreamOrderID];
    if (pStream && pStream != SLOT_RESERVED) {
        dmsg(4,("(yes created)\n"));
        pCreatedStreams[StreamOrderID] = NULL; // free the slot for a new order
    }
    else dmsg(4,("(no not yet created)\n"));
    return pStream;
}


// #########################################################################
// # Disk Thread Only Section
// #         (following code should only be executed by the disk thread)


DiskThread::DiskThread(uint BufferWrapElements) : Thread(false, 1, -2) {
    CreationQueue       = new RingBuffer<create_command_t>(1024);
    DeletionQueue       = new RingBuffer<delete_command_t>(1024);
    GhostQueue          = new RingBuffer<Stream::Handle>(MAX_INPUT_STREAMS);
    Streams             = MAX_INPUT_STREAMS;
    RefillStreamsPerRun = REFILL_STREAMS_PER_RUN;
    for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
        pStreams[i] = new Stream(STREAM_BUFFER_SIZE, BufferWrapElements); // 131072 sample words
    }
    for (int i = 1; i <= MAX_INPUT_STREAMS; i++) {
        pCreatedStreams[i] = NULL;
    }
}

DiskThread::~DiskThread() {
    for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
        if (pStreams[i]) delete pStreams[i];
    }
    if (CreationQueue) delete CreationQueue;
    if (DeletionQueue) delete DeletionQueue;
    if (GhostQueue)    delete GhostQueue;
}

int DiskThread::Main() {
    dmsg(3,("Disk thread running\n"));
    while (true) {
        IsIdle = true; // will be set to false if a stream got filled

        // if there are ghost streams, delete them
        for (int i = 0; i < GhostQueue->read_space(); i++) { //FIXME: unefficient
            Stream::Handle hGhostStream;
            GhostQueue->pop(&hGhostStream);
            bool found = false;
            for (int i = 0; i < this->Streams; i++) {
                if (pStreams[i]->GetHandle() == hGhostStream) {
                    pStreams[i]->Kill();
                    found = true;
                    break;
                }
            }
            if (!found) GhostQueue->push(&hGhostStream); // put ghost stream handle back to the queue
        }

        // if there are creation commands, create new streams
        while (Stream::UnusedStreams > 0 && CreationQueue->read_space() > 0) {
            create_command_t command;
            CreationQueue->pop(&command);
            CreateStream(command);
        }

        // if there are deletion commands, delete those streams
        while (Stream::UnusedStreams < Streams && DeletionQueue->read_space() > 0) {
            delete_command_t command;
            DeletionQueue->pop(&command);
            DeleteStream(command);
        }

        RefillStreams(); // refill the most empty streams

        // if nothing was done during this iteration (eg no streambuffer
        // filled with data) then sleep for 50ms
        if (IsIdle) usleep(30000);

        int streamsInUsage = 0;
        for (int i = Streams - 1; i >= 0; i--) {
            if (pStreams[i]->GetState() != Stream::state_unused) streamsInUsage++;
        }
        ActiveStreamCount = streamsInUsage;
        if (streamsInUsage > ActiveStreamCountMax) ActiveStreamCountMax = streamsInUsage;
    }

    return EXIT_FAILURE;
}

void DiskThread::CreateStream(create_command_t& Command) {
    // search for unused stream
    Stream* newstream = NULL;
    for (int i = Streams - 1; i >= 0; i--) {
        if (pStreams[i]->GetState() == Stream::state_unused) {
            newstream = pStreams[i];
            break;
        }
    }
    if (!newstream) {
        std::cerr << "No unused stream found (OrderID:" << Command.OrderID << ") - report if this happens, this is a bug!\n" << std::flush;
        return;
    }
    newstream->Launch(Command.hStream, Command.pStreamRef, Command.pSample, Command.SampleOffset, Command.DoLoop);
    dmsg(4,("new Stream launched by disk thread (OrderID:%d,StreamHandle:%d)\n", Command.OrderID, Command.hStream));
    if (pCreatedStreams[Command.OrderID] != SLOT_RESERVED) {
        std::cerr << "DiskThread: Slot " << Command.OrderID << " already occupied! Please report this!\n" << std::flush;
        newstream->Kill();
        return;
    }
    pCreatedStreams[Command.OrderID] = newstream;
}

void DiskThread::DeleteStream(delete_command_t& Command) {
    if (Command.pStream) Command.pStream->Kill();
    else { // the stream wasn't created by disk thread or picked up by audio thread yet

        // if stream was created but not picked up yet
        Stream* pStream = pCreatedStreams[Command.OrderID];
        if (pStream && pStream != SLOT_RESERVED) {
            pStream->Kill();
            pCreatedStreams[Command.OrderID] = NULL; // free slot for new order
            return;
        }

        // the stream was not created yet
        if (GhostQueue->write_space() > 0) {
            GhostQueue->push(&Command.hStream);
        }
        else dmsg(1,("DiskThread: GhostQueue full!\n"));
    }
}

void DiskThread::RefillStreams() {
    // sort the streams by most empty stream
    qsort(pStreams, Streams, sizeof(Stream*), CompareStreamWriteSpace);

    // refill the most empty streams
    for (uint i = 0; i < RefillStreamsPerRun; i++) {
        if (pStreams[i]->GetState() == Stream::state_active) {

            //float filledpercentage = (float) pStreams[i]->GetReadSpace() / 131072.0 * 100.0;
            //dmsg(("\nbuffer fill: %.1f%\n", filledpercentage));

            int writespace = pStreams[i]->GetWriteSpaceToEnd();
            if (writespace == 0) break;

            int capped_writespace = writespace;
            // if there is too much buffer space available then cut the read/write
            // size to MAX_REFILL_SIZE which is by default 65536 samples = 256KBytes
            if (writespace > MAX_REFILL_SIZE) capped_writespace = MAX_REFILL_SIZE;

            // adjust the amount to read in order to ensure that the buffer wraps correctly
            int read_amount = pStreams[i]->AdjustWriteSpaceToAvoidBoundary(writespace, capped_writespace);
            // if we wasn't able to refill one of the stream buffers by more than
            // MIN_REFILL_SIZE we'll send the disk thread to sleep later
            if (pStreams[i]->ReadAhead(read_amount) > MIN_REFILL_SIZE) this->IsIdle = false;
        }
    }
}

/// Handle Generator
Stream::Handle DiskThread::CreateHandle() {
    static uint32_t counter = 0;
    if (counter == 0xffffffff) counter = 1; // we use '0' as 'invalid handle' only, so we skip 0
    else                       counter++;
    return counter;
}

/// order ID Generator
Stream::OrderID_t DiskThread::CreateOrderID() {
    static uint32_t counter = 0;
    for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
        if (counter == MAX_INPUT_STREAMS) counter = 1; // we use '0' as 'invalid order' only, so we skip 0
        else                              counter++;
        if (!pCreatedStreams[counter]) {
            pCreatedStreams[counter] = SLOT_RESERVED; // mark this slot as reserved
            return counter;                           // found empty slot
        }
    }
    return 0; // no free slot
}


// *********** C functions **************
// *

/**
 * This is the comparison function the qsort algo uses to determine if a value is
 * bigger than another one or special in our case; if the writespace of a stream
 * is bigger than another one.
 */
int CompareStreamWriteSpace(const void* A, const void* B) {
    Stream* a = *(Stream**) A;
    Stream* b = *(Stream**) B;
    return b->GetWriteSpace() - a->GetWriteSpace();
}
1	/***************************************************************************
2	* *
3	* LinuxSampler - modular, streaming capable sampler *
4	* *
5	* Copyright (C) 2003 by Benno Senoner *
6	* *
7	* This program is free software; you can redistribute it and/or modify *
8	* it under the terms of the GNU General Public License as published by *
9	* the Free Software Foundation; either version 2 of the License, or *
10	* (at your option) any later version. *
11	* *
12	* This program is distributed in the hope that it will be useful, *
13	* but WITHOUT ANY WARRANTY; without even the implied warranty of *
14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
15	* GNU General Public License for more details. *
16	* *
17	* You should have received a copy of the GNU General Public License *
18	* along with this program; if not, write to the Free Software *
19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
20	* MA 02111-1307 USA *
21	***************************************************************************/
22
23	#include "diskthread.h"
24
25
26	// ********* DiskThread ************
27	// *
28
29
30	// just a placeholder to mark a cell in the pickup array as 'reserved'
31	Stream* DiskThread::SLOT_RESERVED = (Stream*) &SLOT_RESERVED;
32
33
34	// #########################################################################
35	// # Foreign Thread Section
36	// # (following code intended to be interface for audio thread)
37
38
39	/**
40	* Suspend disk thread, kill all active streams, clear all queues and the
41	* pickup array and reset all streams. Call this method to bring everything
42	* in the disk thread to day one. If the disk thread was running, it will be
43	* respawned right after everything was reset.
44	*/
45	void DiskThread::Reset() {
46	bool running = this->IsRunning();
47	if (running) this->StopThread();
48	for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
49	pStreams[i]->Kill();
50	}
51	for (int i = 1; i <= MAX_INPUT_STREAMS; i++) {
52	pCreatedStreams[i] = NULL;
53	}
54	GhostQueue->init();
55	CreationQueue->init();
56	DeletionQueue->init();
57	ActiveStreamCount = 0;
58	ActiveStreamCountMax = 0;
59	if (running) this->StartThread(); // start thread only if it was running before
60	}
61
62	String DiskThread::GetBufferFillBytes() {
63	bool activestreams = false;
64	std::stringstream ss;
65	for (uint i = 0; i < this->Streams; i++) {
66	if (pStreams[i]->GetState() == Stream::state_unused) continue;
67	uint bufferfill = pStreams[i]->GetReadSpace() * sizeof(sample_t);
68	uint streamid = (uint) pStreams[i]->GetHandle();
69	if (!streamid) continue;
70
71	if (activestreams) ss << ",[" << streamid << ']' << bufferfill;
72	else {
73	ss << '[' << streamid << ']' << bufferfill;
74	activestreams = true;
75	}
76	}
77	return ss.str();
78	}
79
80	String DiskThread::GetBufferFillPercentage() {
81	bool activestreams = false;
82	std::stringstream ss;
83	for (uint i = 0; i < this->Streams; i++) {
84	if (pStreams[i]->GetState() == Stream::state_unused) continue;
85	uint bufferfill = (uint) ((float) pStreams[i]->GetReadSpace() / (float) STREAM_BUFFER_SIZE * 100);
86	uint streamid = (uint) pStreams[i]->GetHandle();
87	if (!streamid) continue;
88
89	if (activestreams) ss << ",[" << streamid << ']' << bufferfill << '%';
90	else {
91	ss << '[' << streamid << ']' << bufferfill;
92	activestreams = true;
93	}
94	}
95	return ss.str();
96	}
97
98	/**
99	* Returns -1 if command queue or pickup pool is full, 0 on success (will be
100	* called by audio thread within the voice class).
101	*/
102	int DiskThread::OrderNewStream(Stream::reference_t* pStreamRef, gig::Sample* pSample, unsigned long SampleOffset, bool DoLoop) {
103	dmsg(4,("Disk Thread: new stream ordered\n"));
104	if (CreationQueue->write_space() < 1) {
105	dmsg(1,("DiskThread: Order queue full!\n"));
106	return -1;
107	}
108
109	pStreamRef->State = Stream::state_active;
110	pStreamRef->OrderID = CreateOrderID();
111	pStreamRef->hStream = CreateHandle();
112	pStreamRef->pStream = NULL; // a stream has to be activated by the disk thread first
113
114	if (!pStreamRef->OrderID) return -1; // there was no free slot
115
116	create_command_t cmd;
117	cmd.OrderID = pStreamRef->OrderID;
118	cmd.hStream = pStreamRef->hStream;
119	cmd.pStreamRef = pStreamRef;
120	cmd.pSample = pSample;
121	cmd.SampleOffset = SampleOffset;
122	cmd.DoLoop = DoLoop;
123
124	CreationQueue->push(&cmd);
125	return 0;
126	}
127
128	/**
129	* Returns -1 if command queue is full, 0 on success (will be called by audio
130	* thread within the voice class).
131	*/
132	int DiskThread::OrderDeletionOfStream(Stream::reference_t* pStreamRef) {
133	dmsg(4,("Disk Thread: stream deletion ordered\n"));
134	if (DeletionQueue->write_space() < 1) {
135	dmsg(1,("DiskThread: Deletion queue full!\n"));
136	return -1;
137	}
138
139	delete_command_t cmd;
140	cmd.pStream = pStreamRef->pStream;
141	cmd.hStream = pStreamRef->hStream;
142	cmd.OrderID = pStreamRef->OrderID;
143
144	DeletionQueue->push(&cmd);
145	return 0;
146	}
147
148	/**
149	* Returns the pointer to a disk stream if the ordered disk stream
150	* represented by the \a StreamOrderID was already activated by the disk
151	* thread, returns NULL otherwise. If the call was successful, thus if it
152	* returned a valid stream pointer, the caller has to the store that pointer
153	* by himself, because it's not possible to call this method again with the
154	* same used order ID; this method is just intended for picking up an ordered
155	* disk stream. This method will usually be called by the voice class (within
156	* the audio thread).
157	*
158	* @param StreamOrderID - ID previously returned by OrderNewStream()
159	* @returns pointer to created stream object, NULL otherwise
160	*/
161	Stream* DiskThread::AskForCreatedStream(Stream::OrderID_t StreamOrderID) {
162	dmsg(4,("Disk Thread: been asked if stream already created, OrderID=%x ", StreamOrderID));
163	Stream* pStream = pCreatedStreams[StreamOrderID];
164	if (pStream && pStream != SLOT_RESERVED) {
165	dmsg(4,("(yes created)\n"));
166	pCreatedStreams[StreamOrderID] = NULL; // free the slot for a new order
167	}
168	else dmsg(4,("(no not yet created)\n"));
169	return pStream;
170	}
171
172
173
174	// #########################################################################
175	// # Disk Thread Only Section
176	// # (following code should only be executed by the disk thread)
177
178
179	DiskThread::DiskThread(uint BufferWrapElements) : Thread(false, 1, -2) {
180	CreationQueue = new RingBuffer<create_command_t>(1024);
181	DeletionQueue = new RingBuffer<delete_command_t>(1024);
182	GhostQueue = new RingBuffer<Stream::Handle>(MAX_INPUT_STREAMS);
183	Streams = MAX_INPUT_STREAMS;
184	RefillStreamsPerRun = REFILL_STREAMS_PER_RUN;
185	for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
186	pStreams[i] = new Stream(STREAM_BUFFER_SIZE, BufferWrapElements); // 131072 sample words
187	}
188	for (int i = 1; i <= MAX_INPUT_STREAMS; i++) {
189	pCreatedStreams[i] = NULL;
190	}
191	}
192
193	DiskThread::~DiskThread() {
194	for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
195	if (pStreams[i]) delete pStreams[i];
196	}
197	if (CreationQueue) delete CreationQueue;
198	if (DeletionQueue) delete DeletionQueue;
199	if (GhostQueue) delete GhostQueue;
200	}
201
202	int DiskThread::Main() {
203	dmsg(3,("Disk thread running\n"));
204	while (true) {
205	IsIdle = true; // will be set to false if a stream got filled
206
207	// if there are ghost streams, delete them
208	for (int i = 0; i < GhostQueue->read_space(); i++) { //FIXME: unefficient
209	Stream::Handle hGhostStream;
210	GhostQueue->pop(&hGhostStream);
211	bool found = false;
212	for (int i = 0; i < this->Streams; i++) {
213	if (pStreams[i]->GetHandle() == hGhostStream) {
214	pStreams[i]->Kill();
215	found = true;
216	break;
217	}
218	}
219	if (!found) GhostQueue->push(&hGhostStream); // put ghost stream handle back to the queue
220	}
221
222	// if there are creation commands, create new streams
223	while (Stream::UnusedStreams > 0 && CreationQueue->read_space() > 0) {
224	create_command_t command;
225	CreationQueue->pop(&command);
226	CreateStream(command);
227	}
228
229	// if there are deletion commands, delete those streams
230	while (Stream::UnusedStreams < Streams && DeletionQueue->read_space() > 0) {
231	delete_command_t command;
232	DeletionQueue->pop(&command);
233	DeleteStream(command);
234	}
235
236	RefillStreams(); // refill the most empty streams
237
238	// if nothing was done during this iteration (eg no streambuffer
239	// filled with data) then sleep for 50ms
240	if (IsIdle) usleep(30000);
241
242	int streamsInUsage = 0;
243	for (int i = Streams - 1; i >= 0; i--) {
244	if (pStreams[i]->GetState() != Stream::state_unused) streamsInUsage++;
245	}
246	ActiveStreamCount = streamsInUsage;
247	if (streamsInUsage > ActiveStreamCountMax) ActiveStreamCountMax = streamsInUsage;
248	}
249
250	return EXIT_FAILURE;
251	}
252
253	void DiskThread::CreateStream(create_command_t& Command) {
254	// search for unused stream
255	Stream* newstream = NULL;
256	for (int i = Streams - 1; i >= 0; i--) {
257	if (pStreams[i]->GetState() == Stream::state_unused) {
258	newstream = pStreams[i];
259	break;
260	}
261	}
262	if (!newstream) {
263	std::cerr << "No unused stream found (OrderID:" << Command.OrderID << ") - report if this happens, this is a bug!\n" << std::flush;
264	return;
265	}
266	newstream->Launch(Command.hStream, Command.pStreamRef, Command.pSample, Command.SampleOffset, Command.DoLoop);
267	dmsg(4,("new Stream launched by disk thread (OrderID:%d,StreamHandle:%d)\n", Command.OrderID, Command.hStream));
268	if (pCreatedStreams[Command.OrderID] != SLOT_RESERVED) {
269	std::cerr << "DiskThread: Slot " << Command.OrderID << " already occupied! Please report this!\n" << std::flush;
270	newstream->Kill();
271	return;
272	}
273	pCreatedStreams[Command.OrderID] = newstream;
274	}
275
276	void DiskThread::DeleteStream(delete_command_t& Command) {
277	if (Command.pStream) Command.pStream->Kill();
278	else { // the stream wasn't created by disk thread or picked up by audio thread yet
279
280	// if stream was created but not picked up yet
281	Stream* pStream = pCreatedStreams[Command.OrderID];
282	if (pStream && pStream != SLOT_RESERVED) {
283	pStream->Kill();
284	pCreatedStreams[Command.OrderID] = NULL; // free slot for new order
285	return;
286	}
287
288	// the stream was not created yet
289	if (GhostQueue->write_space() > 0) {
290	GhostQueue->push(&Command.hStream);
291	}
292	else dmsg(1,("DiskThread: GhostQueue full!\n"));
293	}
294	}
295
296	void DiskThread::RefillStreams() {
297	// sort the streams by most empty stream
298	qsort(pStreams, Streams, sizeof(Stream*), CompareStreamWriteSpace);
299
300	// refill the most empty streams
301	for (uint i = 0; i < RefillStreamsPerRun; i++) {
302	if (pStreams[i]->GetState() == Stream::state_active) {
303
304	//float filledpercentage = (float) pStreams[i]->GetReadSpace() / 131072.0 * 100.0;
305	//dmsg(("\nbuffer fill: %.1f%\n", filledpercentage));
306
307	int writespace = pStreams[i]->GetWriteSpaceToEnd();
308	if (writespace == 0) break;
309
310	int capped_writespace = writespace;
311	// if there is too much buffer space available then cut the read/write
312	// size to MAX_REFILL_SIZE which is by default 65536 samples = 256KBytes
313	if (writespace > MAX_REFILL_SIZE) capped_writespace = MAX_REFILL_SIZE;
314
315	// adjust the amount to read in order to ensure that the buffer wraps correctly
316	int read_amount = pStreams[i]->AdjustWriteSpaceToAvoidBoundary(writespace, capped_writespace);
317	// if we wasn't able to refill one of the stream buffers by more than
318	// MIN_REFILL_SIZE we'll send the disk thread to sleep later
319	if (pStreams[i]->ReadAhead(read_amount) > MIN_REFILL_SIZE) this->IsIdle = false;
320	}
321	}
322	}
323
324	/// Handle Generator
325	Stream::Handle DiskThread::CreateHandle() {
326	static uint32_t counter = 0;
327	if (counter == 0xffffffff) counter = 1; // we use '0' as 'invalid handle' only, so we skip 0
328	else counter++;
329	return counter;
330	}
331
332	/// order ID Generator
333	Stream::OrderID_t DiskThread::CreateOrderID() {
334	static uint32_t counter = 0;
335	for (int i = 0; i < MAX_INPUT_STREAMS; i++) {
336	if (counter == MAX_INPUT_STREAMS) counter = 1; // we use '0' as 'invalid order' only, so we skip 0
337	else counter++;
338	if (!pCreatedStreams[counter]) {
339	pCreatedStreams[counter] = SLOT_RESERVED; // mark this slot as reserved
340	return counter; // found empty slot
341	}
342	}
343	return 0; // no free slot
344	}
345
346
347
348	// ********* C functions ************
349	// *
350
351	/**
352	* This is the comparison function the qsort algo uses to determine if a value is
353	* bigger than another one or special in our case; if the writespace of a stream
354	* is bigger than another one.
355	*/
356	int CompareStreamWriteSpace(const void* A, const void* B) {
357	Stream* a = (Stream*) A;
358	Stream* b = (Stream*) B;
359	return b->GetWriteSpace() - a->GetWriteSpace();
360	}