Vcpkg: MSYS2 acquisition failed

[bogdanlytvynovskyi]

Describe the bug
When doing fresh build from vcpkg anything that requires msys2, build will fail due to repo.msys2.org being down

Environment

• OS: Windows
• Compiler: NA

To Reproduce
Steps to reproduce the behavior:

1. ./vcpkg install ffmpeg
2. See error

Expected behavior
I would expect for msys retrieval code target mirrors in case repo.msys2.org is down

msys2 issue reported here: https://github.com/msys2/MSYS2-packages/issues/1884

[JackBoosY]

Related: #1098

[Voskrese]

copy
https://github.com/msys2/MSYS2-packages/tree/master/pacman-mirrors

to
...\vcpkg\downloads\toolsmsys2msys64\etc\pacman.d

[bogdanlytvynovskyi]

@JackBoosY - it seems that vcpkg_acquire_msys.cmake has support for mirrors. Following patch did a trick for me. Would you kindly take care of creating proper PR for this?
msys2_mirror.txt

[MaverickTse]

@JackBoosY - it seems that vcpkg_acquire_msys.cmake has support for mirrors. Following patch did a trick for me. Would you kindly take care of creating proper PR for this?
msys2_mirror.txt

The one reason that I'm reluctant to make a PR is that any "mirror" hardcoded in the cmake script is going to receive increased traffic, and I cannot tell if any mirror is more reliable than others (Personal server is out, China server... may not be comfortable for everyone).

Also the pacman -Syu command will also access the default repo.msys2.org.

In addition, running pacman -Syu from a 2018 archive can take quite a while and MAY break msys2 itself.

[bogdanlytvynovskyi]

The one reason that I'm reluctant to make a PR is that any "mirror" hardcoded in the cmake script is going to receive increased traffic, and I cannot tell if any mirror is more reliable than others

This is the reason mirrors exist, unless I am missing something. Working is better than non working IMO.

Also the pacman -Syu command will also access the default repo.msys2.org.

Yes it does, and then resorts to other mirrors.

In addition, running pacman -Syu from a 2018 archive can take quite a while and MAY break msys2 itself

Not sure specifically about this concern. I took exactly same version as currently used and it worked pretty well for me

[ylluminate]

After a fresh install from downloading and installing from a nightly installer build, where do you put the mirror list so that pacman -Syu works again?

Out of the box this simply fails and doesn't try to pull from mirrors for me...

[MaverickTse]

At lease the 20190524 xz version works for me. Tested with building icu:x64-windows. The older 2018 version has problem with mirror however.
I'd refrain from using nightly... can be too buggy for an important infrastructure

[MaverickTse]

There is a PKGBUILD package in the github msys2 repo that handles mirror:

https://github.com/msys2/MSYS2-packages/tree/master/pacman-mirrors