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dep/cubeb: Update to dc511c6

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This commit is contained in:
Connor McLaughlin
2022-08-05 17:28:17 +10:00
parent 06ecc50797
commit 8f45bf7f27
50 changed files with 5667 additions and 4813 deletions
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137
dep/cubeb/src/cubeb_ringbuffer.h
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@ -18,10 +18,10 @@
/**
* Single producer single consumer lock-free and wait-free ring buffer.
*
* This data structure allows producing data from one thread, and consuming it on
* another thread, safely and without explicit synchronization. If used on two
* threads, this data structure uses atomics for thread safety. It is possible
* to disable the use of atomics at compile time and only use this data
* This data structure allows producing data from one thread, and consuming it
* on another thread, safely and without explicit synchronization. If used on
* two threads, this data structure uses atomics for thread safety. It is
* possible to disable the use of atomics at compile time and only use this data
* structure on one thread.
*
* The role for the producer and the consumer must be constant, i.e., the
@ -48,9 +48,7 @@
* providing an external buffer to copy into is an easy way to have linear
* data for further processing.
*/
template <typename T>
class ring_buffer_base
{
template <typename T> class ring_buffer_base {
public:
/**
* Constructor for a ring buffer.
@ -61,11 +59,10 @@ public:
* @param capacity The maximum number of element this ring buffer will hold.
*/
ring_buffer_base(int capacity)
/* One more element to distinguish from empty and full buffer. */
: capacity_(capacity + 1)
/* One more element to distinguish from empty and full buffer. */
: capacity_(capacity + 1)
{
assert(storage_capacity() <
std::numeric_limits<int>::max() / 2 &&
assert(storage_capacity() < std::numeric_limits<int>::max() / 2 &&
"buffer too large for the type of index used.");
assert(capacity_ > 0);
@ -84,10 +81,7 @@ public:
* @param count The number of elements to enqueue.
* @return The number of element enqueued.
*/
int enqueue_default(int count)
{
return enqueue(nullptr, count);
}
int enqueue_default(int count) { return enqueue(nullptr, count); }
/**
* @brief Put an element in the queue
*
@ -97,20 +91,18 @@ public:
*
* @return 1 if the element was inserted, 0 otherwise.
*/
int enqueue(T& element)
{
return enqueue(&element, 1);
}
int enqueue(T & element) { return enqueue(&element, 1); }
/**
* Push `count` elements in the ring buffer.
*
* Only safely called on the producer thread.
*
* @param elements a pointer to a buffer containing at least `count` elements.
* If `elements` is nullptr, zero or default constructed elements are enqueued.
* If `elements` is nullptr, zero or default constructed elements are
* enqueued.
* @param count The number of elements to read from `elements`
* @return The number of elements successfully coped from `elements` and inserted
* into the ring buffer.
* @return The number of elements successfully coped from `elements` and
* inserted into the ring buffer.
*/
int enqueue(T * elements, int count)
{
@ -118,19 +110,17 @@ public:
assert_correct_thread(producer_id);
#endif
int rd_idx = read_index_.load(std::memory_order::memory_order_relaxed);
int wr_idx = write_index_.load(std::memory_order::memory_order_relaxed);
int wr_idx = write_index_.load(std::memory_order_relaxed);
int rd_idx = read_index_.load(std::memory_order_acquire);
if (full_internal(rd_idx, wr_idx)) {
return 0;
}
int to_write =
std::min(available_write_internal(rd_idx, wr_idx), count);
int to_write = std::min(available_write_internal(rd_idx, wr_idx), count);
/* First part, from the write index to the end of the array. */
int first_part = std::min(storage_capacity() - wr_idx,
to_write);
int first_part = std::min(storage_capacity() - wr_idx, to_write);
/* Second part, from the beginning of the array */
int second_part = to_write - first_part;
@ -142,7 +132,8 @@ public:
ConstructDefault(data_.get(), second_part);
}
write_index_.store(increment_index(wr_idx, to_write), std::memory_order::memory_order_release);
write_index_.store(increment_index(wr_idx, to_write),
std::memory_order_release);
return to_write;
}
@ -163,15 +154,14 @@ public:
assert_correct_thread(consumer_id);
#endif
int wr_idx = write_index_.load(std::memory_order::memory_order_acquire);
int rd_idx = read_index_.load(std::memory_order::memory_order_relaxed);
int rd_idx = read_index_.load(std::memory_order_relaxed);
int wr_idx = write_index_.load(std::memory_order_acquire);
if (empty_internal(rd_idx, wr_idx)) {
return 0;
}
int to_read =
std::min(available_read_internal(rd_idx, wr_idx), count);
int to_read = std::min(available_read_internal(rd_idx, wr_idx), count);
int first_part = std::min(storage_capacity() - rd_idx, to_read);
int second_part = to_read - first_part;
@ -181,7 +171,8 @@ public:
Copy(elements + first_part, data_.get(), second_part);
}
read_index_.store(increment_index(rd_idx, to_read), std::memory_order::memory_order_relaxed);
read_index_.store(increment_index(rd_idx, to_read),
std::memory_order_release);
return to_read;
}
@ -197,8 +188,9 @@ public:
#ifndef NDEBUG
assert_correct_thread(consumer_id);
#endif
return available_read_internal(read_index_.load(std::memory_order::memory_order_relaxed),
write_index_.load(std::memory_order::memory_order_relaxed));
return available_read_internal(
read_index_.load(std::memory_order_relaxed),
write_index_.load(std::memory_order_acquire));
}
/**
* Get the number of available elements for consuming.
@ -212,8 +204,9 @@ public:
#ifndef NDEBUG
assert_correct_thread(producer_id);
#endif
return available_write_internal(read_index_.load(std::memory_order::memory_order_relaxed),
write_index_.load(std::memory_order::memory_order_relaxed));
return available_write_internal(
read_index_.load(std::memory_order_acquire),
write_index_.load(std::memory_order_relaxed));
}
/**
* Get the total capacity, for this ring buffer.
@ -222,10 +215,7 @@ public:
*
* @return The maximum capacity of this ring buffer.
*/
int capacity() const
{
return storage_capacity() - 1;
}
int capacity() const { return storage_capacity() - 1; }
/**
* Reset the consumer and producer thread identifier, in case the thread are
* being changed. This has to be externally synchronized. This is no-op when
@ -237,6 +227,7 @@ public:
consumer_id = producer_id = std::thread::id();
#endif
}
private:
/** Return true if the ring buffer is empty.
*
@ -244,8 +235,7 @@ private:
* @param write_index the write index to consider
* @return true if the ring buffer is empty, false otherwise.
**/
bool empty_internal(int read_index,
int write_index) const
bool empty_internal(int read_index, int write_index) const
{
return write_index == read_index;
}
@ -258,8 +248,7 @@ private:
* @param write_index the write index to consider
* @return true if the ring buffer is full, false otherwise.
**/
bool full_internal(int read_index,
int write_index) const
bool full_internal(int read_index, int write_index) const
{
return (write_index + 1) % storage_capacity() == read_index;
}
@ -269,18 +258,13 @@ private:
*
* @return the number of elements that can be stored in the buffer.
*/
int storage_capacity() const
{
return capacity_;
}
int storage_capacity() const { return capacity_; }
/**
* Returns the number of elements available for reading.
*
* @return the number of available elements for reading.
*/
int
available_read_internal(int read_index,
int write_index) const
int available_read_internal(int read_index, int write_index) const
{
if (write_index >= read_index) {
return write_index - read_index;
@ -293,9 +277,7 @@ private:
*
* @return the number of elements that can be written into the array.
*/
int
available_write_internal(int read_index,
int write_index) const
int available_write_internal(int read_index, int write_index) const
{
/* We substract one element here to always keep at least one sample
* free in the buffer, to distinguish between full and empty array. */
@ -312,8 +294,7 @@ private:
* @param increment the number by which `index` is incremented.
* @return the new index.
*/
int
increment_index(int index, int increment) const
int increment_index(int index, int increment) const
{
assert(increment >= 0);
return (index + increment) % storage_capacity();
@ -325,7 +306,7 @@ private:
* @param id the id of the thread that has called the calling method first.
*/
#ifndef NDEBUG
static void assert_correct_thread(std::thread::id& id)
static void assert_correct_thread(std::thread::id & id)
{
if (id == std::thread::id()) {
id = std::this_thread::get_id();
@ -354,9 +335,7 @@ private:
/**
* Adapter for `ring_buffer_base` that exposes an interface in frames.
*/
template <typename T>
class audio_ring_buffer_base
{
template <typename T> class audio_ring_buffer_base {
public:
/**
* @brief Constructor.
@ -365,8 +344,8 @@ public:
* @param capacity_in_frames The capacity in frames.
*/
audio_ring_buffer_base(int channel_count, int capacity_in_frames)
: channel_count(channel_count)
, ring_buffer(frames_to_samples(capacity_in_frames))
: channel_count(channel_count),
ring_buffer(frames_to_samples(capacity_in_frames))
{
assert(channel_count > 0);
}
@ -380,7 +359,8 @@ public:
*/
int enqueue_default(int frame_count)
{
return samples_to_frames(ring_buffer.enqueue(nullptr, frames_to_samples(frame_count)));
return samples_to_frames(
ring_buffer.enqueue(nullptr, frames_to_samples(frame_count)));
}
/**
* @brief Enqueue `frames_count` frames of audio.
@ -396,7 +376,8 @@ public:
int enqueue(T * frames, int frame_count)
{
return samples_to_frames(ring_buffer.enqueue(frames, frames_to_samples(frame_count)));
return samples_to_frames(
ring_buffer.enqueue(frames, frames_to_samples(frame_count)));
}
/**
@ -413,7 +394,8 @@ public:
*/
int dequeue(T * frames, int frame_count)
{
return samples_to_frames(ring_buffer.dequeue(frames, frames_to_samples(frame_count)));
return samples_to_frames(
ring_buffer.dequeue(frames, frames_to_samples(frame_count)));
}
/**
* Get the number of available frames of audio for consuming.
@ -444,10 +426,8 @@ public:
*
* @return The maximum capacity of this ring buffer.
*/
int capacity() const
{
return samples_to_frames(ring_buffer.capacity());
}
int capacity() const { return samples_to_frames(ring_buffer.capacity()); }
private:
/**
* @brief Frames to samples conversion.
@ -456,10 +436,7 @@ private:
*
* @return A number of samples.
*/
int frames_to_samples(int frames) const
{
return frames * channel_count;
}
int frames_to_samples(int frames) const { return frames * channel_count; }
/**
* @brief Samples to frames conversion.
*
@ -467,10 +444,7 @@ private:
*
* @return A number of frames.
*/
int samples_to_frames(int samples) const
{
return samples / channel_count;
}
int samples_to_frames(int samples) const { return samples / channel_count; }
/** Number of channels of audio that will stream through this ring buffer. */
int channel_count;
/** The underlying ring buffer that is used to store the data. */
@ -482,14 +456,13 @@ private:
* from two threads, one producer, one consumer (that never change role),
* without explicit synchronization.
*/
template<typename T>
using lock_free_queue = ring_buffer_base<T>;
template <typename T> using lock_free_queue = ring_buffer_base<T>;
/**
* Lock-free instantiation of the `audio_ring_buffer` type. This is safe to use
* from two threads, one producer, one consumer (that never change role),
* without explicit synchronization.
*/
template<typename T>
template <typename T>
using lock_free_audio_ring_buffer = audio_ring_buffer_base<T>;
#endif // CUBEB_RING_BUFFER_H