(ITS#8324) LMDB - grow file incrementally on Windows

Full_Name: Howard Chu Version: LMDB 0.9.17 OS: Win32 x64 URL: ftp://ftp.openldap.org/incoming/ Submission from: (NULL) (78.155.236.172) Submitted by: hyc

Currently LMDB uses the WIN32 API to setup the memory-mapped DB file, which requires that the file size is equal to the map size. If we use the native NT API instead it's possible to grow the file incrementally, which will reduce the number of complaints we get from Windows users who think their disk space is getting eaten up for no reason.

There is probably a performance reduction from taking this approach, but I haven't benchmarked it and have no plans to. I frankly don't care and no one is paying me to care.