re: https://github.com/Unidata/netcdf-c/issues/1614
NetCDF has a requirement that the type of a _FillValue attribute
be the same as the containing variable. However, it is clear
that too many servers do not honor this requirement. So, change
the default for DAP2 and DAP4 to allow fill mismatch.
* Replace wholevar with more useful wholechunk optimization
* Add optimization to read multiple values at one time
* Replace NCDEFAULT_get/put_vars with native nczarr versions.
* Clarify chunk projection computations
* zdebdispatch.h
* Add more chunking test cases and re-enable run_chunkcases
* If !szip, then suppress deflate interference test
* Make H5Znoop(1) filter produce more information
* cleanup bzlib.c API
* Turn back on the DAP2 remote tests, but leave DAP4 remote tests disabled.
* Turn on selected non-remote DAP4 tests
* Replace d4crc32 with the equivalents in libdispatch
re: https://github.com/Unidata/netcdf-c/issues/1923
re: https://github.com/Unidata/netcdf-c/issues/1921
The issue was raised about the order of returned filter ids
for nc_inq_var_filter_ids() when creating a file as opposed
to later reading the file.
For creation, the order is the same as the order in which the
calls to nc_def_var_filter() occur.
However, after the file is closed and then reopened for reading,
the question was raised if the returned order is the same or the reverse.
In fact the order is the same in both cases.
This PR extends the existing filter order testcase to check the create
versus read orders. This also required changing the H5Znoop(1) filters
in the plugins directory.
Misc. Unrelated Changes
1. fix calls to fdopen under windows
2. Temporarily suppres the nczarr_tests/run_chunkcases test
since it seems to be causing problems with github actions.
If the user is opening a existing file for appending (NC_WRITE) in parallel and the file is in CDF5 format, the `NC_interpret_magic_number()` routine clears the `model->impl` setting of `NC_FORMATX_PNETCDF` which was set in `NC_omodeinfer` (See lines following the `done:` label in that routine which specifically set the `impl` if `useparallel` is true.)
This setting then gets overwritten when `NC_interpret_magic_number` is called which sets the `model->impl` back to `NC_FORMATX_NC3`. This can (did) cause problems with parallel output as the `NC3` format does not correctly handle parallel writing but the `PNETCDF` does.
Not sure if this is the best place for the test, but it did fix the parallel write issues I was seeing...
If you need more details on what is happening, let me know. But a restatement at a higher level is that I was calling `nc_open_par` with `NC_WRITE` and `NC_64BIT_DATA` mode and the existing file has `CDF5` for the magic number. However, the dispatcher was being set to `NC3_dispatch_table` instead of `NCP_dispatch_table` which is the dispatcher which had been chosen for the original creation of the file being appended to.
I was then getting zeroes in the data being written to the vars since NC3 wasn't correctly handling multiple MPI ranks writing to different parts of the same variable...
The `NC_HAS_MULTIFILTERS` line in `netcdf_meta.h` was not of the correct form -- showed as
```
#define NC_HAS_MULTIFILTERS
```
Instead of the better form:
```
#define NC_HAS_MULTIFILTERS 0 (or 1 if enabled)
```
Primary Fixes:
* Add a whole variable optimization -- used in the rare case that nc_get/put_vara covers the whole of a variable and the variable has a single chunk.
* Fix chunking error when stride causes whole chunks to be skipped.
* Fix some memory leaks
* Add test cases
* Add one performance test to nczarr_test/. This uses the timer utils from unit_test: timer_utils.[ch].
* Move ncdumpchunks utility from ncdump to nczarr_test
Misc. Other Changes:
* Make check for aws libraries conditional on --enable-nczarr-s3
* Remove all but one bm tests from nczarr_test until they are working.
* Remove another dependency on HDF5 from supposedly non-HDF5 specific code; specifically hdf5_log_hdf5.
* Make the BAIL2 macro be hdf5 specific and replace elsewhere with an HDF5 independent equivalent.
* Move hdf5cache.c to libsrc4/nc4cache.c because it is used by nczarr.
* Modify unit_tests so that some of them are run even if using Windows.
* Misc. small bug fixes and refactors and memory leaks.
* Rename some conflicting tests for cmake.
* Attempted to make nc_perf work with cmake and failed.
Re: GH Issue https://github.com/Unidata/netcdf-c/issues/1900
Apparently the clock_gettime() function is not always available.
It is used in unit_test/tst_exhash.c and unit_test/tst_xcache.c.
To solve this, a number of things were changed:
* Move the timing code to a new file unit_tests/timer_utils.[ch]
* Modify the timing code to choose one of several timing methods
depending on availability. The prioritized order is as follows:
1. If Windows, use the QueryPerformanceCounter mechanism else
2. Use clock_gettime if available else
3. Use gettimeofday if available else
4. Use getrusage if available
Note that the resolution of 3 and 4 is less than 1 or 2.
Misc. Other Changes:
* Move the test in CMakeLists.txt that disables unit tests for WIN32 to unit_test/CMakeLists.txt since some unit tests actually work under Visual Studio.
* Fix some of the unit tests to work under visual studio
* Fix problem with using remove() in zmap_nzf.c
* Remove some warning about use of EXTERNL
