path: root/examples/widgets/tools/completer/fsmodel.h
diff options
authorVolker Hilsheimer <>2019-07-26 16:17:53 +0200
committerVolker Hilsheimer <>2019-08-10 22:04:11 +0200
commitb7d073e9905bf9812ba96cecdcf6871a95517d30 (patch)
treeab48181deddd93f40cff5e908f243c44efc359c5 /examples/widgets/tools/completer/fsmodel.h
parente75aed1a96e626f079af307c5604ddf9054ecafc (diff)
Refactor memory allocation for arguments of QMetaCallEvents
There are two cases: In a BlockingQueuedConnection, QMetaCallEvent doesn't allocate memory and instead passes already existing pointers through. A QSemaphore is used to serialize data access between threads. So the constructor taking a QSemaphore can be simplified to only accept an existing arg array. In a QueuedConnection, QMetaCallEvent needs to make deep copies of the arguments, and memory needs to be allocated based on the number of arguments. The previous code put the burden of memory allocation on the code generating the event, while the memory was free'd by ~QMetaCallEvent. Instead, make it QMetaCallEvent's responsibility to allocate and free the memory as needed, and adjust the code generating QMetaCallEvents. We can allocate the memory for types and pointers to arguments in a single block, starting with the space for the array of void*, followed by the space for the array of integers to avoid byte alignment issues. By pre-allocating the space that's needed by three arguments, we can avoid all mallocs for the majority of QMetaCallEvents. Until this change has propagated through qt5.git, we need to keep the old API that is still used by QtDeclarative around. Once QtDeclarative has migrated to the new API, it can be removed. Change-Id: Id7359ffc14897237ea9672dabae9ef199a821907 Reviewed-by: Simon Hausmann <>
Diffstat (limited to 'examples/widgets/tools/completer/fsmodel.h')
0 files changed, 0 insertions, 0 deletions