1 files changed, 135 insertions, 0 deletions

diff --git a/src/core/hle/service/nvflinger/buffer_queue_core.cpp b/src/core/hle/service/nvflinger/buffer_queue_core.cpp
new file mode 100644
index 000000000..a6ff46aa9
--- /dev/null
+++ b/src/core/hle/service/nvflinger/buffer_queue_core.cpp
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright 2021 yuzu Emulator Project
+// Copyright 2014 The Android Open Source Project
+// Parts of this implementation were base on:
+// https://cs.android.com/android/platform/superproject/+/android-5.1.1_r38:frameworks/native/libs/gui/BufferQueueCore.cpp
+
+#include "common/assert.h"
+
+#include "core/hle/service/nvflinger/buffer_queue_core.h"
+
+namespace android {
+
+BufferQueueCore::BufferQueueCore() : lock{mutex} {
+    // This is locked on creation, so unlock.
+    lock.unlock();
+
+    for (s32 slot = 0; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
+        free_slots.insert(slot);
+    }
+}
+
+void BufferQueueCore::NotifyShutdown() {
+    std::unique_lock<std::mutex> lk(mutex);
+
+    is_shutting_down = true;
+
+    SignalDequeueCondition();
+}
+
+void BufferQueueCore::SignalDequeueCondition() {
+    dequeue_condition.notify_all();
+}
+
+bool BufferQueueCore::WaitForDequeueCondition() {
+    if (is_shutting_down) {
+        return false;
+    }
+
+    dequeue_condition.wait(lock);
+
+    return true;
+}
+
+s32 BufferQueueCore::GetMinUndequeuedBufferCountLocked(bool async) const {
+    // If DequeueBuffer is allowed to error out, we don't have to add an extra buffer.
+    if (!use_async_buffer) {
+        return max_acquired_buffer_count;
+    }
+
+    if (dequeue_buffer_cannot_block || async) {
+        return max_acquired_buffer_count + 1;
+    }
+
+    return max_acquired_buffer_count;
+}
+
+s32 BufferQueueCore::GetMinMaxBufferCountLocked(bool async) const {
+    return GetMinUndequeuedBufferCountLocked(async) + 1;
+}
+
+s32 BufferQueueCore::GetMaxBufferCountLocked(bool async) const {
+    const auto min_buffer_count = GetMinMaxBufferCountLocked(async);
+    auto max_buffer_count = std::max(default_max_buffer_count, min_buffer_count);
+
+    if (override_max_buffer_count != 0) {
+        ASSERT(override_max_buffer_count >= min_buffer_count);
+        max_buffer_count = override_max_buffer_count;
+    }
+
+    // Any buffers that are dequeued by the producer or sitting in the queue waiting to be consumed
+    // need to have their slots preserved.
+    for (s32 slot = max_buffer_count; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
+        const auto state = slots[slot].buffer_state;
+        if (state == BufferState::Queued || state == BufferState::Dequeued) {
+            max_buffer_count = slot + 1;
+        }
+    }
+
+    return max_buffer_count;
+}
+
+s32 BufferQueueCore::GetPreallocatedBufferCountLocked() const {
+    return static_cast<s32>(std::count_if(slots.begin(), slots.end(),
+                                          [](const auto& slot) { return slot.is_preallocated; }));
+}
+
+void BufferQueueCore::FreeBufferLocked(s32 slot) {
+    LOG_DEBUG(Service_NVFlinger, "slot {}", slot);
+
+    const auto had_buffer = slots[slot].graphic_buffer != nullptr;
+
+    slots[slot].graphic_buffer.reset();
+
+    if (slots[slot].buffer_state == BufferState::Acquired) {
+        slots[slot].needs_cleanup_on_release = true;
+    }
+
+    if (slots[slot].buffer_state != BufferState::Free) {
+        free_slots.insert(slot);
+    } else if (had_buffer) {
+        // If the slot was FREE, but we had a buffer, we need to move this slot from the free
+        // buffers list to the the free slots list.
+        free_buffers.remove(slot);
+        free_slots.insert(slot);
+    }
+
+    slots[slot].buffer_state = BufferState::Free;
+    slots[slot].acquire_called = false;
+    slots[slot].frame_number = 0;
+    slots[slot].fence = Fence::NoFence();
+}
+
+void BufferQueueCore::FreeAllBuffersLocked() {
+    queue.clear();
+    buffer_has_been_queued = false;
+
+    for (s32 slot = 0; slot < BufferQueueDefs::NUM_BUFFER_SLOTS; ++slot) {
+        FreeBufferLocked(slot);
+    }
+}
+
+bool BufferQueueCore::StillTracking(const BufferItem* item) const {
+    const BufferSlot& slot = slots[item->slot];
+
+    return (slot.graphic_buffer != nullptr) && (item->graphic_buffer == slot.graphic_buffer);
+}
+
+void BufferQueueCore::WaitWhileAllocatingLocked() const {
+    while (is_allocating) {
+        std::unique_lock<std::mutex> lk(mutex);
+        is_allocating_condition.wait(lk);
+    }
+}
+
+} // namespace android