re: https://github.com/Unidata/netcdf-c/issues/1154
Inadvertently, the behavior of NC_DISKLESS with nc_create() was
changed in release 4.6.1. Previously, the NC_WRITE flag needed
to be explicitly used with NC_DISKLESS in order to cause the
created file to be persisted to disk.
Additional analyis indicated that the current NC_DISKLESS
implementation was seriously flawed.
This PR attempts to clean up and regularize the situation with
respect to NC_DISKLESS control. One important aspect of diskless
operation is that there are two different notions of write.
1. The file is read-write vs read-only when using the netcdf API.
2. The file is persisted or not to disk at nc_close().
Previously, these two were conflated. The rules now are
as follows.
1. NC_DISKLESS + NC_WRITE means that the file is read/write using the netcdf API
2. NC_DISKLESS + NC_PERSIST means that the file is persisted to a disk file at nc_close.
3. NC_DISKLESS + NC_PERSIST + NC_WRITE means both 1 and 2.
The NC_PERSIST flag is new and takes over the obsolete NC_MPIPOSIX flag.
NC_MPIPOSIX is still defined, but is now an alias for the NC_MPIIO flag.
It is also now the case that for netcdf-4, NC_DISKLESS is independent
of NC_INMEMORY and in fact it is an error to specify both flags
simultaneously.
Finally, the MMAP code was fixed to use NC_PERSIST as well.
Also marked MMAP as deprecated.
Also added a test case to test various combinations of NC_DISKLESS,
NC_PERSIST, and NC_WRITE.
This PR affects a number of files and especially test cases
that used NC_DISKLESS.
Misc. Unrelated fixes
1. fixed some warnings in ncdump/dumplib.c
In turn that caused some problems elsewhere because some files
did not include netcdf.h preceding netcdf_mem.h. Specifically,
building under visual studio fails.
So fix those cases that I can find. May need to
add more later.
re: github issue https://github.com/Unidata/netcdf-c/issues/1111
One of the less common use cases for the in-memory feature is
apparently failing with HDF5-1.10.x. The fix is complicated and
requires significant changes to libhdf5/nc4memcb.c. The current
setup is detailed in the file docs/inmeminternal.dox.
Additionally, it was discovered that the program
nc_test/tst_inmemory.c, which is invoked by
nc_test/run_inmemory.sh, actually was failing because of the
above problem. But the failure is not detected since the script
does not return non-zero value.
Other Changes:
1. Fix nc_test_tst_inmemory to return errors correctly.
2. Make ncdap_tests/findtestserver.c and dap4_tests/findtestserver4.c
be generated from ncdap_test/findtestserver.c.in.
3. Make LOG() print output to stderr instead of stdout to
avoid contaminating e.g. ncdump output.
4. Modify the handling of NC_INMEMORY and NC_DISKLESS flags
to properly handle that NC_DISKLESS => NC_INMEMORY. This
affects a number of code pieces, especially memio.c.
stored in the _NCProperties attribute to allow two things:
1. capture of additional library dependencies (over and above
hdf5)
2. Recognition of non-netcdf libraries that create netcdf-4 format
files.
To this end, the _NCProperties format has been extended to be
and arbitrary set of key=value pairs separated by commas.
This new format has version = 2, and uses commas as the pair separator.
Thus the general form is:
_NCProperties = "version=2,key1=value,key2=value2..." ;
This new version is accompanied by a new ./configure option of the form
--with-ncproperties="key1=value1,key2=value2..."
that specifies pairs to add to the _NCProperties attribute for all
files created with that netcdf library.
At this point, what is missing is some programmatic way to
specify either all the pairs or additional pairs
to the _NCProperties attribute. Not sure of the best way
to do this.
Builders using non-netcdf libraries can specify
whatever they want in the key value pairs (as long
as the version=2 is specified first).
By convention, the primary library is expected to be the
the first pair after the leading version=2 pair, but this
is convention only and is neither required nor enforced.
Related changes:
1. Fixed the tests that check _NCProperties to properly operate with version=2.
2. When reading a version 1 _NCProperties attribute, convert it to look
like a version 2 attribute.
2. Added some version 2 tests to ncdump/tst_fileinfo.c and
ncdump/tst_fileinfo.sh
Misc Changes:
1. Fix minor problem in ncdap_test/testurl.sh where a parameter to
buildurl needed to be quoted.
2. Minor fix to ncgen to swap switches -H and -h to be consistent
with other utilities.
3. Document the -M flag in nccopy usage() and the nccopy man page.
4. Modify a test case to use the nccopy -M flag.
The fix includes the following changes.
1. Checking and using the default file format at file create time is now
done only when the create mode (argument cmode) does not include any
format related flags, i.e. NC_64BIT_OFFSET, NC_64BIT_DATA,
NC_CLASSIC_MODEL, and NC_NETCDF4.
2. Adjustment of cmode based on the default format is now done in
NC_create() only. The idea is to adjust cmode before entering the
dispatcher's file create subroutine.
3. Any adjustment of cmode is removed from all I/O dispatchers, i.e.
NC4_create(), NC3_create(), and NCP_create().
4. Checking for illegal cmode has been done in check_create_mode() called
in NC_create(). This commit removes the redundant checking from
NCP_create().
5. Remove PnetCDF tests in nc_test/tst_names.c, so it can focus on testing
all classic formats and netCDF4 formats.
Two new test programs are added. They can be used to test netCDF with and
without this commit.
1. nc_test/tst_default_format.c
2. nc_test/tst_default_format_pnetcdf.c (use when PnetCDF is enabled).
re: github issue https://github.com/Unidata/netcdf-fortran/issues/82
This was originally discovered in the Fortran tests, but is
a problem in the C library.
The problem only occurred when using HDF5-1.10.x. The reason it
failed is that starting with 1.10, the hid_t type was changed
from 32 bits to 64 bits.
The function libsrc4/nc4memcb.c#NC4_image_init was using type int (doh!)
to return the hdf fileid instead of hid_t type. This, of course,
caused the id to be truncated and in turn later use of the id
caused hdf5 to fail.
Fix is trivial: replace int with hid_t. This also requires a related
change in nc4mem.c.
Also added the test case derived from the original Fortran code.
You would think I would learn...
corresponding HDF5 operations.
re: github issue https://github.com/Unidata/netcdf-c/issues/908
also in reference to https://github.com/pydata/xarray/issues/2004
The netcdf-c library has implemented the nc_get_vars and nc_put_vars
operations as element at a time. This has resulted in very slow
operation.
This pr attempts to improve the situation for netcdf-4/hdf5 files
by using the slab operations provided by the hdf5 library. The new
implementation passes the get/put vars stride information down to
the hdf5 slab operations.
The result appears to improve performance significantly. Some simple
tests on large 2-D arrays shows speedups in excess of 150.
Misc. other changes:
1. fix bug in ncgen/semantics.c; using a list's allocated length
instead of actual length.
2. Added a temporary hook in the netcdf library plus a performance
test case (tst_varsperf.c) to estimate the speedup. After users
have had some experience with this, I will remove it, probably
after the 4.7 release.
Fix https://github.com/Unidata/netcdf-c/issues/962
1. remove the --disable-diskless option since it is no
longer needed. Similarly for CMakeLists.txt.
2. Fixed nc4files.c where BAIL and return were mixed
leading to situation where cleanup code was not
being invoked. This probably occurs elsewhere,
but I did not find any specifically.
