Fix crash when ColorSpace references itself directly.

Also fixes any problems with cycles between colorspaces.

Past fixes have solved problems with CPDF_DocPageData::GetColorSpace()
calling itself and CPDF_DocPageData::GetColorSpace() calling
CPDF_ColorSpace::Load() and vice versa. They have not solved
CPDF_ColorSpace::Load() calling itself.

This CL repurposes the |pVisited| set to ensure CPDF_ColorSpace::Load()
does not try to load a colorspace as a dependency of itself and
creates |pVisitedLocal| to ensure CPDF_DocPageData::GetColorSpace()
does not create a similar circular dependency not involving
CPDF_ColorSpace::Load().

Bug: chromium:828206
Change-Id: Ib2d0ec494be169135607f3651e0f70627b26ebd7
Reviewed-on: https://pdfium-review.googlesource.com/29810
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 36ee859264..a51e3f4609 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2980,6 +2980,7 @@ test("pdfium_unittests") {
 test("pdfium_embeddertests") {
   sources = [
     "core/fpdfapi/edit/cpdf_creator_embeddertest.cpp",
+    "core/fpdfapi/page/cpdf_docpagedata_embeddertest.cpp",
     "core/fpdfapi/page/cpdf_stitchfunc_embeddertest.cpp",
     "core/fpdfapi/parser/cpdf_parser_embeddertest.cpp",
     "core/fpdfapi/parser/cpdf_security_handler_embeddertest.cpp",