pipewire: Revise plugin code. Closes: #1401

- Use RingBuf from audcore
- Respect output_buffer_size setting
- Improve get_delay() and drain() functions
- Add support for 5 and 7 channels

Co-authored-by: Thomas Lange <[email protected]>

src/pipewire/pipewire.cc

@@ -28,6 +28,7 @@
 
 #include <libaudcore/i18n.h>
 #include <libaudcore/plugin.h>
+#include <libaudcore/ringbuf.h>
 #include <libaudcore/runtime.h>
 
 #if !PW_CHECK_VERSION(0, 3, 33)
@@ -103,8 +104,9 @@ class PipeWireOutput : public OutputPlugin
     int m_aud_format = 0;
     int m_core_init_seq = 0;
 
-    unsigned char * m_buffer = nullptr;
-    unsigned int m_buffer_at = 0;
+    timespec m_time {};
+
+    RingBuf<unsigned char> m_buffer;
     unsigned int m_buffer_size = 0;
     unsigned int m_frames = 0;
     unsigned int m_stride = 0;
@@ -159,36 +161,61 @@ void PipeWireOutput::pause(bool pause)
 {
     pw_thread_loop_lock(m_loop);
     pw_stream_set_active(m_stream, !pause);
+    clock_gettime(CLOCK_REALTIME, &m_time);
     pw_thread_loop_unlock(m_loop);
 }
 
 int PipeWireOutput::get_delay()
 {
-    return (m_buffer_at / m_stride + m_frames) * 1000 / m_rate;
+    int buff_time = (((m_buffer.len() + m_buffer_size) / m_stride) * 1000) / m_rate;
+
+    // Get time difference from last buffer fill
+    timespec time_now {};
+    clock_gettime(CLOCK_REALTIME, &time_now);
+
+    int time_diff =
+        (((time_now.tv_sec - m_time.tv_sec) * 1000000000) +
+         (time_now.tv_nsec - m_time.tv_nsec)) / 1000000;
+
+    if (time_diff < 0)
+        time_diff = 0;
+    if (time_diff > buff_time)
+        time_diff = buff_time;
+
+    return buff_time - time_diff;
 }
 
 void PipeWireOutput::drain()
 {
     pw_thread_loop_lock(m_loop);
-    if (m_buffer_at > 0)
-        pw_thread_loop_timed_wait(m_loop, 2);
+
+    int buflen;
+    while ((buflen = m_buffer.len()) > 0)
+    {
+        pw_thread_loop_timed_wait(m_loop, 1);
+        if (buflen <= m_buffer.len())
+        {
+            AUDERR("PipeWireOutput: buffer drain lock\n");
+            break;
+        }
+    }
 
     pw_stream_flush(m_stream, true);
-    pw_thread_loop_timed_wait(m_loop, 2);
+    pw_thread_loop_timed_wait(m_loop, 1);
     pw_thread_loop_unlock(m_loop);
 }
 
 void PipeWireOutput::flush()
 {
     pw_thread_loop_lock(m_loop);
-    m_buffer_at = 0;
+    m_buffer.discard();
     pw_thread_loop_unlock(m_loop);
     pw_stream_flush(m_stream, false);
 }
 
 void PipeWireOutput::period_wait()
 {
-    if (m_buffer_at != m_buffer_size)
+    if (m_buffer.space())
         return;
 
     pw_thread_loop_lock(m_loop);
@@ -200,12 +227,11 @@ int PipeWireOutput::write_audio(const void * data, int length)
 {
     pw_thread_loop_lock(m_loop);
 
-    auto size = aud::min<size_t>(m_buffer_size - m_buffer_at, length);
-    memcpy(m_buffer + m_buffer_at, data, size);
-    m_buffer_at += size;
+    length = aud::min(length, m_buffer.space());
+    m_buffer.copy_in(static_cast<const unsigned char *>(data), length);
 
     pw_thread_loop_unlock(m_loop);
-    return size;
+    return length;
 }
 
 void PipeWireOutput::close_audio()
@@ -248,11 +274,7 @@ void PipeWireOutput::close_audio()
         m_loop = nullptr;
     }
 
-    if (m_buffer)
-    {
-        delete[] m_buffer;
-        m_buffer = nullptr;
-    }
+    m_buffer.destroy();
 }
 
 bool PipeWireOutput::open_audio(int format, int rate, int channels, String & error)
@@ -267,6 +289,7 @@ bool PipeWireOutput::open_audio(int format, int rate, int channels, String & err
         return false;
     }
 
+    clock_gettime(CLOCK_REALTIME, &m_time);
     return true;
 }
 
@@ -343,10 +366,9 @@ bool PipeWireOutput::init_core()
         return false;
     }
 
+    m_frames = aud_get_int("output_buffer_size") * m_rate / 1000;
     m_stride = FMT_SIZEOF(m_aud_format) * m_channels;
-    m_frames = aud::clamp<int>(64, ceilf(2048 * m_rate / 48000.0f), 8192);
-    m_buffer_size = m_frames * m_stride;
-    m_buffer = new unsigned char[m_buffer_size];
+    m_buffer.alloc(m_frames * m_stride);
 
     return true;
 }
@@ -490,7 +512,9 @@ void PipeWireOutput::on_process(void * data)
     struct spa_buffer * buf;
     void * dst;
 
-    if (!o->m_buffer_at)
+    clock_gettime(CLOCK_REALTIME, &o->m_time);
+
+    if (!o->m_buffer.len())
     {
         pw_thread_loop_signal(o->m_loop, false);
         return;
@@ -510,13 +534,12 @@ void PipeWireOutput::on_process(void * data)
         return;
     }
 
-    auto size = aud::min<uint32_t>(buf->datas[0].maxsize, o->m_buffer_at);
-    memcpy(dst, o->m_buffer, size);
-    o->m_buffer_at -= size;
-    memmove(o->m_buffer, o->m_buffer + size, o->m_buffer_at);
+    auto size = aud::min<uint32_t>(buf->datas[0].maxsize, o->m_buffer.len());
+    o->m_buffer_size = size;
+    o->m_buffer.move_out(static_cast<unsigned char *>(dst), size);
 
     b->buffer->datas[0].chunk->offset = 0;
-    b->buffer->datas[0].chunk->size = o->m_buffer_size;
+    b->buffer->datas[0].chunk->size = size;
     b->buffer->datas[0].chunk->stride = o->m_stride;
 
     pw_stream_queue_buffer(o->m_stream, b);
@@ -570,15 +593,18 @@ void PipeWireOutput::set_channel_map(struct spa_audio_info_raw * info, int chann
             info->position[8] = SPA_AUDIO_CHANNEL_RC;
             // Fall through
         case 8:
+        case 7:
             info->position[6] = SPA_AUDIO_CHANNEL_FLC;
             info->position[7] = SPA_AUDIO_CHANNEL_FRC;
             // Fall through
         case 6:
+        case 5:
             info->position[4] = SPA_AUDIO_CHANNEL_RL;
             info->position[5] = SPA_AUDIO_CHANNEL_RR;
             // Fall through
         case 4:
-            info->position[3] = SPA_AUDIO_CHANNEL_LFE;
+            if (channels != 5 && channels != 7)
+                info->position[3] = SPA_AUDIO_CHANNEL_LFE;
             // Fall through
         case 3:
             info->position[2] = SPA_AUDIO_CHANNEL_FC;