support both cimfs and cimwriter dlls#2587
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nits in comments; but LGTM overall
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| //sys CimMergeMountVerifiedImage(numCimPaths uint32, backingImagePaths *CimFsImagePath, flags uint32, volumeID *g, hashSize uint16, hash *byte) (hr error) = cimfs.CimMergeMountVerifiedImage | ||
| // pickSupported makes sure we use appropriate syscalls depending on which DLLs are present. | ||
| func pickSupported[F any](cimWriterFunc, cimfsFunc F) F { | ||
| if cimwriter.Supported() { |
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Is there a way to log which CIM dll gets used but not for each syscall?
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added logging to the function used by snapshotter.
The PR introducing `cimwriter.dll` was a breaking change, which is fixed in this PR. Split CIM syscalls into separate packages for `cimfs.dll` and `cimwriter.dll`, with shared types in `internal/winapi/types/`. Add `pickSupported()` to prefer `cimwriter.dll` for write operations and fall back to `cimfs.dll` when `cimwriter.dll` is not present. Mount, dismount, and verification operations always use `cimfs.dll`. Relax `CimFsSupported()` to only require cimfs.dll instead of both DLLs (the breaking change). Signed-off-by: Maksim An <maksiman@microsoft.com>
Regenerate zsyscall_windows.go files for the new cimfs and cimwriter packages after PR feedback. Signed-off-by: Maksim An <maksiman@microsoft.com>
Allow `cimwriter.dll` and `cimfs.dll` to be loaded from outside the system directory. Log the resolved DLL path on load using `GetModuleFileName`. Add `LogCimDLLSupport()` to report which DLL is active for write operations, called from `CreateBlockCIMWithOptions` on every block CIM creation. Add `TestMain` in `pkg/cimfs` to print DLL availability in test output. Signed-off-by: Maksim An <maksiman@microsoft.com>
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The PR introducing
cimwriter.dllwas a breaking change, which is fixed in this PR.Add both
cimfs.dllandcimwriter.dllsyscalls and only usecimwriter.dllwhen present.Add logging to indicate which one is used: