libcamera: request: Make Request class Extensible

Implement the D-Pointer design pattern in the Request class to allow
changing internal data without affecting the public ABI.

Move the internal fields that are not needed to implement the public
API to the Request::Private class already. This allows to remove
the friend class declaration for the PipelineHandler class, which can
now use the Request::Private API.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[Move all internal fields to Request::Private and remove friend  declaration]
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

4 files changed, 62 insertions, 20 deletions

diff --git a/include/libcamera/internal/meson.build b/include/libcamera/internal/meson.build
index a96bbb95..c9e055d4 100644
--- a/include/libcamera/internal/meson.build
+++ b/include/libcamera/internal/meson.build
@@ -35,6 +35,7 @@ libcamera_internal_headers = files([
     'pipeline_handler.h',
     'process.h',
     'pub_key.h',
+    'request.h',
     'source_paths.h',
     'sysfs.h',
     'v4l2_device.h',
diff --git a/include/libcamera/internal/request.h b/include/libcamera/internal/request.h
new file mode 100644
index 00000000..1340ffa2
--- /dev/null
+++ b/include/libcamera/internal/request.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * request.h - Request class private data
+ */
+#ifndef __LIBCAMERA_INTERNAL_REQUEST_H__
+#define __LIBCAMERA_INTERNAL_REQUEST_H__
+
+#include <memory>
+
+#include <libcamera/request.h>
+
+namespace libcamera {
+
+class Camera;
+class FrameBuffer;
+
+class Request::Private : public Extensible::Private
+{
+	LIBCAMERA_DECLARE_PUBLIC(Request)
+
+public:
+	Private(Camera *camera);
+	~Private();
+
+	Camera *camera() const { return camera_; }
+	bool hasPendingBuffers() const;
+
+	bool completeBuffer(FrameBuffer *buffer);
+	void complete();
+	void cancel();
+	void reuse();
+
+private:
+	friend class PipelineHandler;
+
+	void doCancelRequest();
+
+	Camera *camera_;
+	bool cancelled_;
+	uint32_t sequence_ = 0;
+
+	std::unordered_set<FrameBuffer *> pending_;
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_INTERNAL_REQUEST_H__ */
diff --git a/include/libcamera/internal/tracepoints/request.tp b/include/libcamera/internal/tracepoints/request.tp
index 37d8c46f..f039ffd4 100644
--- a/include/libcamera/internal/tracepoints/request.tp
+++ b/include/libcamera/internal/tracepoints/request.tp
@@ -5,8 +5,9 @@
  * request.tp - Tracepoints for the request object
  */
 
+#include <libcamera/internal/request.h>
+
 #include <libcamera/framebuffer.h>
-#include <libcamera/request.h>
 
 TRACEPOINT_EVENT_CLASS(
 	libcamera,
@@ -62,7 +63,7 @@ TRACEPOINT_EVENT_INSTANCE(
 	request,
 	request_complete,
 	TP_ARGS(
-		libcamera::Request *, req
+		libcamera::Request::Private *, req
 	)
 )
 
@@ -71,7 +72,7 @@ TRACEPOINT_EVENT_INSTANCE(
 	request,
 	request_cancel,
 	TP_ARGS(
-		libcamera::Request *, req
+		libcamera::Request::Private *, req
 	)
 )
 
@@ -79,13 +80,13 @@ TRACEPOINT_EVENT(
 	libcamera,
 	request_complete_buffer,
 	TP_ARGS(
-		libcamera::Request *, req,
+		libcamera::Request::Private *, req,
 		libcamera::FrameBuffer *, buf
 	),
 	TP_FIELDS(
 		ctf_integer_hex(uintptr_t, request, reinterpret_cast<uintptr_t>(req))
-		ctf_integer(uint64_t, cookie, req->cookie())
-		ctf_integer(int, status, req->status())
+		ctf_integer(uint64_t, cookie, req->_o<libcamera::Request>()->cookie())
+		ctf_integer(int, status, req->_o<libcamera::Request>()->status())
 		ctf_integer_hex(uintptr_t, buffer, reinterpret_cast<uintptr_t>(buf))
 		ctf_enum(libcamera, buffer_status, uint32_t, buf_status, buf->metadata().status)
 	)
diff --git a/include/libcamera/request.h b/include/libcamera/request.h
index f434335b..8c78970d 100644
--- a/include/libcamera/request.h
+++ b/include/libcamera/request.h
@@ -25,8 +25,10 @@ class CameraControlValidator;
 class FrameBuffer;
 class Stream;
 
-class Request
+class Request : public Extensible
 {
+	LIBCAMERA_DECLARE_PRIVATE()
+
 public:
 	enum Status {
 		RequestPending,
@@ -52,34 +54,23 @@ public:
 	int addBuffer(const Stream *stream, FrameBuffer *buffer);
 	FrameBuffer *findBuffer(const Stream *stream) const;
 
-	uint32_t sequence() const { return sequence_; }
+	uint32_t sequence() const;
 	uint64_t cookie() const { return cookie_; }
 	Status status() const { return status_; }
 
-	bool hasPendingBuffers() const { return !pending_.empty(); }
+	bool hasPendingBuffers() const;
 
 	std::string toString() const;
 
 private:
 	LIBCAMERA_DISABLE_COPY(Request)
 
-	friend class PipelineHandler;
-
-	void complete();
-	void cancel();
-
-	bool completeBuffer(FrameBuffer *buffer);
-
-	Camera *camera_;
 	ControlList *controls_;
 	ControlList *metadata_;
 	BufferMap bufferMap_;
-	std::unordered_set<FrameBuffer *> pending_;
 
-	uint32_t sequence_;
 	const uint64_t cookie_;
 	Status status_;
-	bool cancelled_;
 };
 
 } /* namespace libcamera */