tree b1d2f4d8803c73968bc65a5c89782115c6cba6cd
parent f91ca5a72358bb0b00b4da9481b21fe668157614
author Tom Sepez <tsepez@google.com> 1788893549 -0700
committer pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1788893549 -0700

Ignore re-entrant form calls during passive FFI callbacks

Passive FFI callbacks (e.g. FFI_OutputSelectedRect, FFI_Invalidate)
are notifications invoked during internal operations such as painting.
Embedders must not re-entrantly execute form actions or load/close
pages during these callbacks.

Track passive callbacks using CPDFSDK_FormFillEnvironment's
in_passive_ffi_callback_ flag, and early-return from entry points
such as FORM_OnAfterLoadPage, FORM_OnBeforeClosePage, and
FORM_Do*Action when invoked re-entrantly.

Active retrieval callbacks such as FFI_GetPage remain unflagged, as
page loading is expected in those paths.

TAG=agy
CONV=9e87637a-cb01-4106-9c04-ad4da437fc61

Bug: 556535630
Change-Id: Id892141ce082cc8895b4ed5dc66af3edaf5ef740
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/156913
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>