1 files changed, 91 insertions, 0 deletions
diff --git a/src/android/mm/generic_camera_buffer.cpp b/src/android/mm/generic_camera_buffer.cpp
new file mode 100644
index 00000000..166be36e
--- /dev/null
+++ b/src/android/mm/generic_camera_buffer.cpp
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * generic_camera_buffer.cpp - Generic Android frame buffer backend
+ */
+
+#include "../camera_buffer.h"
+
+#include <unistd.h>
+
+#include <libcamera/base/log.h>
+
+#include "libcamera/internal/framebuffer.h"
+
+using namespace libcamera;
+
+LOG_DECLARE_CATEGORY(HAL)
+
+class CameraBuffer::Private : public Extensible::Private,
+			      public libcamera::MappedBuffer
+{
+	LIBCAMERA_DECLARE_PUBLIC(CameraBuffer)
+
+public:
+	Private(CameraBuffer *cameraBuffer,
+		buffer_handle_t camera3Buffer, int flags);
+	~Private();
+
+	unsigned int numPlanes() const;
+
+	Span<uint8_t> plane(unsigned int plane);
+
+	size_t jpegBufferSize(size_t maxJpegBufferSize) const;
+};
+
+CameraBuffer::Private::Private(CameraBuffer *cameraBuffer,
+			       buffer_handle_t camera3Buffer, int flags)
+	: Extensible::Private(cameraBuffer)
+{
+	maps_.reserve(camera3Buffer->numFds);
+	error_ = 0;
+
+	for (int i = 0; i < camera3Buffer->numFds; i++) {
+		if (camera3Buffer->data[i] == -1)
+			continue;
+
+		off_t length = lseek(camera3Buffer->data[i], 0, SEEK_END);
+		if (length < 0) {
+			error_ = -errno;
+			LOG(HAL, Error) << "Failed to query plane length";
+			break;
+		}
+
+		void *address = mmap(nullptr, length, flags, MAP_SHARED,
+				     camera3Buffer->data[i], 0);
+		if (address == MAP_FAILED) {
+			error_ = -errno;
+			LOG(HAL, Error) << "Failed to mmap plane";
+			break;
+		}
+
+		maps_.emplace_back(static_cast<uint8_t *>(address),
+				   static_cast<size_t>(length));
+	}
+}
+
+CameraBuffer::Private::~Private()
+{
+}
+
+unsigned int CameraBuffer::Private::numPlanes() const
+{
+	return maps_.size();
+}
+
+Span<uint8_t> CameraBuffer::Private::plane(unsigned int plane)
+{
+	if (plane >= maps_.size())
+		return {};
+
+	return maps_[plane];
+}
+
+size_t CameraBuffer::Private::jpegBufferSize(size_t maxJpegBufferSize) const
+{
+	return std::min<unsigned int>(maps_[0].size(),
+				      maxJpegBufferSize);
+}
+
+PUBLIC_CAMERA_BUFFER_IMPLEMENTATION