From 9df775c7574520632547c2f4db236b7d84f6e3c3 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Thu, 2 Sep 2021 04:29:03 +0300 Subject: libcamera: framebuffer: Allocate metadata planes at construction time The metadata planes are allocated by V4L2VideoDevice when dequeuing a buffer. This causes the metadata planes to only be allocated after a buffer gets dequeued, and doesn't provide any strong guarantee that their number matches the number of FrameBuffer planes. The lack of this invariant makes the FrameBuffer class fragile. As a first step towards fixing this, allocate the metadata planes when the FrameBuffer is constructed. The FrameMetadata API should be further improved by preventing a change in the number of planes. Signed-off-by: Laurent Pinchart Reviewed-by: Jean-Michel Hautbois Reviewed-by: Hirokazu Honda --- src/libcamera/framebuffer.cpp | 2 ++ src/libcamera/v4l2_videodevice.cpp | 10 +++++----- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/src/libcamera/framebuffer.cpp b/src/libcamera/framebuffer.cpp index e71c2ffa..e4f8419a 100644 --- a/src/libcamera/framebuffer.cpp +++ b/src/libcamera/framebuffer.cpp @@ -210,6 +210,8 @@ FrameBuffer::FrameBuffer(const std::vector &planes, unsigned int cookie) : Extensible(std::make_unique()), planes_(planes), cookie_(cookie) { + metadata_.planes.resize(planes_.size()); + unsigned int offset = 0; bool isContiguous = true; ino_t inode = 0; diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp index 281f3f13..81209e48 100644 --- a/src/libcamera/v4l2_videodevice.cpp +++ b/src/libcamera/v4l2_videodevice.cpp @@ -1675,7 +1675,6 @@ FrameBuffer *V4L2VideoDevice::dequeueBuffer() unsigned int numV4l2Planes = multiPlanar ? buf.length : 1; FrameMetadata &metadata = buffer->metadata_; - metadata.planes.clear(); if (numV4l2Planes != buffer->planes().size()) { /* @@ -1705,8 +1704,9 @@ FrameBuffer *V4L2VideoDevice::dequeueBuffer() return buffer; } - metadata.planes.push_back({ std::min(plane.length, bytesused) }); - bytesused -= metadata.planes.back().bytesused; + metadata.planes[i].bytesused = + std::min(plane.length, bytesused); + bytesused -= metadata.planes[i].bytesused; } } else if (multiPlanar) { /* @@ -1715,9 +1715,9 @@ FrameBuffer *V4L2VideoDevice::dequeueBuffer() * V4L2 buffer is guaranteed to be equal at this point. */ for (unsigned int i = 0; i < numV4l2Planes; ++i) - metadata.planes.push_back({ planes[i].bytesused }); + metadata.planes[i].bytesused = planes[i].bytesused; } else { - metadata.planes.push_back({ buf.bytesused }); + metadata.planes[0].bytesused = buf.bytesused; } return buffer; -- cgit v1.2.1