view tests/test-convert-cvsnt-mergepoints.rlog @ 51930:bc9ed92d4753

util: make `mmapread()` work on Windows again

522b4d729e89 started referencing `mmap.MAP_PRIVATE`, but that's not available on
Windows, so `hg version` worked, but `make local` did not.  That commit also
started calling the constructor with the fine-grained `flags` and `prot` args,
but those aren't available on Windows either[1] (though the backing C code
doesn't seem conditionalized to disallow usage of them).

I assume the change away from from the `access` arg was to provide the same
options, plus `MAP_POPULATE`.  Looking at the source code[2], they're not quite
the same- `ACCESS_READ` is equivalent to `flags = MAP_SHARED` and `prot = PROT_READ`.
`MAP_PRIVATE` is only used with `ACCESS_COPY`, which allows read and write.
Therefore, we can't quite get the same baseline flags on Windows, but this was
the status quo ante and `MAP_POPULATE` is a Linux thing, so presumably it works.

I realize that typically the OS differences are abstracted into the platform
modules, but I'm leaving it here so that it is obvious what the differences are
between the platforms.

[1] https://docs.python.org/3/library/mmap.html#mmap.mmap
[2] https://github.com/python/cpython/blob/5e0abb47886bc665eefdcc19fde985f803e49d4c/Modules/mmapmodule.c#L1539

head: 1.2
branch:
locks: strict
access list:
symbolic names:
	MYBRANCH1_2: 1.1.2.2.0.2
	MYBRANCH1_1: 1.1.0.4
	MYBRANCH1: 1.1.0.2
keyword substitution: kv
total revisions: 8;	selected revisions: 8
description:
----------------------------
revision 1.2
date: 2009/04/02 07:00:32;  author: user;  state: Exp;  lines: +1 -1;  kopt: kv;  commitid: 14d449d462903487;  mergepoint: 1.1.2.2.2.1;  filename: foo.txt;
merge
----------------------------
revision 1.1
date: 2009/04/02 06:50:43;  author: user;  state: Exp;  kopt: kv;  commitid: 17ac49d460432d04;  filename: foo.txt;
branches:  1.1.2;  1.1.4;
foo.txt
----------------------------
revision 1.1.4.2
date: 2009/04/02 07:02:51;  author: user;  state: Exp;  lines: +1 -0;  kopt: kv;  commitid: 170049d4631b364d;  mergepoint: 1.1.2.2;  filename: foo.txt;
merge
----------------------------
revision 1.1.4.1
date: 2009/04/02 06:53:42;  author: user;  state: Exp;  lines: +1 -1;  kopt: kv;  commitid: dc849d460f52f49;  filename: foo.txt;
quux
----------------------------
revision 1.1.2.2
date: 2009/04/02 06:53:20;  author: user;  state: Exp;  lines: +1 -1;  kopt: kv;  commitid: 8ec49d460e02f04;  filename: foo.txt;
branches:  1.1.2.2.2;
baz
----------------------------
revision 1.1.2.1
date: 2009/04/02 06:52:38;  author: user;  state: Exp;  lines: +1 -1;  kopt: kv;  commitid: d5049d460b62e7b;  filename: foo.txt;
bar
----------------------------
revision 1.1.2.2.2.1
date: 2009/04/02 06:55:42;  author: user;  state: Exp;  lines: +1 -1;  kopt: kv;  commitid: 11c849d4616d30d1;  filename: foo.txt;
bazzie
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