pgsql: Fix our Windows stat() emulation to handle file sizes > 4GB.

Fix our Windows stat() emulation to handle file sizes > 4GB.

Hack things so that our idea of "struct stat" is equivalent to Windows'
struct __stat64, allowing it to have a wide enough st_size field.

Instead of relying on native stat(), use GetFileInformationByHandle().
This avoids a number of issues with Microsoft's multiple and rather
slipshod emulations of stat(). We still need to jump through hoops
to deal with ERROR_DELETE_PENDING, though :-(

Pull the relevant support code out of dirmod.c and put it into
its own file, win32stat.c.

Still TODO: do we need to do something different with lstat(),
rather than treating it identically to stat()?

Juan José Santamaría Flecha, reviewed by Emil Iggland;
based on prior work by Michael Paquier, Sergey Zubkovsky, and others

Discussion: https://postgr.es/m/1803D792815FC24D871C00D17AE95905CF5099@g01jpexmbkw24
Discussion: https://postgr.es/m/15858-9572469fd3b73263@postgresql.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bed90759fcbcd72d4d06969eebab81e47326f9a2

Modified Files
--------------
configure | 6 +
configure.ac | 1 +
src/include/port/win32_port.h | 44 +++++--
src/port/dirmod.c | 52 --------
src/port/win32stat.c | 299 ++++++++++++++++++++++++++++++++++++++++++
src/tools/msvc/Mkvcbuild.pm | 2 +-
6 files changed, 339 insertions(+), 65 deletions(-)