Root cause: resources and default mount stored pointers tied to the public mjVFS object address. If mjVFS was moved after initialization, resource close/read paths could dereference stale pointers and crash.\n\nThis change stores a stable internal mjVFS handle inside VFS and points resources/default mount to that stable handle. It also tracks the current public owner pointer and rebinds it in Upcast so lifecycle operations (including self-destruct cleanup) target the current mjVFS address after moves.\n\nAdds regression test UserVfsTest.MoveVfsAfterOpenResource, which opens a resource, moves mjVFS, then reads/closes/deletes successfully.
Resource operations (e.g. mju_openResource, mju_readResource, and
mju_closeResource, etc.) are now all handled by a VFS instance. It
is now up to the VFS to determine which provider to use in order to
handle those operations.
This allows us to dynamically add/remove (aka "mount") providers to
a VFS to handle special requests. mj_addFileVFS and mj_addBufferVFS
have been reimplemented as two such use-cases. Moreover, we expose
the mounting behaviour with two new functions: mj_mountVFS and
mj_unmountVFS.
PiperOrigin-RevId: 863248779
Change-Id: I8bcbd5445814ba1e72c6d7b80ad6a054f5f1df57
Resource operations (e.g. mju_openResource, mju_readResource, and
mju_closeResource, etc.) are now all handled by a VFS instance. It
is now up to the VFS to determine which provider to use in order to
handle those operations.
This allows us to dynamically add/remove (aka "mount") providers to
a VFS to handle special requests. mj_addFileVFS and mj_addBufferVFS
have been reimplemented as two such use-cases. Moreover, we expose
the mounting behaviour with two new functions: mj_mountVFS and
mj_unmountVFS.
PiperOrigin-RevId: 861550939
Change-Id: I070eb4bcc2982466c8f368f7918005538baa5185
Resource operations (e.g. mju_openResource, mju_readResource, and
mju_closeResource, etc.) are now all handled by a VFS instance. It
is now up to the VFS to determine which provider to use in order to
handle those operations.
This allows us to dynamically add/remove (aka "mount") providers to
a VFS to handle special requests. mj_addFileVFS and mj_addBufferVFS
have been reimplemented as two such use-cases. Moreover, we expose
the mounting behaviour with two new functions: mj_mountVFS and
mj_unmountVFS.
PiperOrigin-RevId: 856166919
Change-Id: Id723d612ffc0bff020705cf19ef95fbf24676840
Sam Haves