windows: use Go-managed pointer list for ProcThreadAttributeList

It turns out that if you write Go pointers to Go memory, the Go compiler
must be involved so that it generates various calls to the GC in the
process. Letting Windows write Go pointers to Go memory violated this.

We fix this by having all the Windows-managed memory be just a boring
[]byte blob. Then, in order to prevent the GC from prematurely cleaning
up the pointers referenced by that []byte blob, or in the future moving
memory and attempting to fix up pointers, we copy the data to the
Windows heap and then maintain a little array of pointers that have been
used. Every time the Update function is called with a new pointer, we
make a copy and append it to the list.  Then, on Delete, we free the
pointers from the Windows heap.

Updates golang/go#44900.

Change-Id: I42340a93fd9f6b8d10340634cf833fd4559a5f4f
Reviewed-on: https://go-review.googlesource.com/c/sys/+/300369
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
3 files changed
tree: 7ee73677c4fe2a5395fdb813b1da1f10f78d135c
  1. .gitattributes
  2. .gitignore
  3. AUTHORS
  4. CONTRIBUTING.md
  5. CONTRIBUTORS
  6. LICENSE
  7. PATENTS
  8. README.md
  9. codereview.cfg
  10. cpu/
  11. execabs/
  12. go.mod
  13. internal/
  14. plan9/
  15. unix/
  16. windows/
README.md

sys

Go Reference

This repository holds supplemental Go packages for low-level interactions with the operating system.

Download/Install

The easiest way to install is to run go get -u golang.org/x/sys. You can also manually git clone the repository to $GOPATH/src/golang.org/x/sys.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://golang.org/doc/contribute.html.

The main issue tracker for the sys repository is located at https://github.com/golang/go/issues. Prefix your issue with “x/sys:” in the subject line, so it is easy to find.