Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2688)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2688)

Fixes #4740

The MSYS2 run-time convert arguments that look like paths when
executing a program unless that application is linked with the MSYS
run-time.  The exact conversion rules are listed here:

    http://www.mingw.org/wiki/Posix_path_conversion

With the built-in configurations (all having names starting with
"mingw"), the openssl application is not linked with the MSYS2
run-time, and therefore, it will receive possibly converted arguments
from the process that executes it.  This conversion is fine for normal
path arguments, but it happens that some arguments to the openssl
application get converted when they shouldn't.  In one case, it's
arguments like '-passin file:something', and in another, it's a file:
URI (what typically happens is that URIs without an authority
component get converted, 'cause the conversion mechanism doesn't
recognise them as URIs).

To avoid conversion where we don't want it, we simply assign
MSYS2_ARG_CONV_EXCL a pattern to avoid specific conversions.  As a
precaution, we only do this where we obviously need it.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
Reviewed-by: NBen Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/4765)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4332)

Some URIs get "mistreated" (converted) by the MSYS run-time.
Unfortunately, avoiding this conversion doesn't help either.

    http://www.mingw.org/wiki/Posix_path_conversion

Fixes #4314
Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4322)

Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4047)

These cases are performed on Linux only.  They check that files with
names starting with 'file:' can be processed as well.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3907)

We haven't tested plain absolute paths without making them URIs...
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3907)

to_rel_file_uri really treated all files appropriately, absolute and
relative alike, and really just constructs a URI, so gets renamed to
to_file_uri

to_file_uri, on the other hand, forces the path into an absolute one,
so gets renamed to to_abs_file_uri
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3907)

These tests were inspired by OpenConnect and incorporated
by permission of David Woodhouse under CLA
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3542)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3542)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3542)

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3542)