re: https://github.com/Unidata/netcdf-c/issues/1584
Support has been added for multiple filters per variable. This
affects a number of components in netcdf. The new APIs are
documented in NUG/filters.md.
The primary changes are:
* A set of new functions are provided (see __include/netcdf_filter.h__).
- Obtain a list of the filters associated with a variable
- Obtain the parameters for a specific filter.
* The existing __nc_inq_var_filter__ function now returns info
about the first defined filter.
* The utilities (ncgen, ncdump, and nccopy) now support
an extended format for specifying a sequence of filters.
The general form is __<filter>|<filter>..._.
* The ncdump **_Filter** attribute now dumps a list of all the
filters associated with a variable using the above new format.
* Filter specifications can now use a filter name instead of number
for filters known to the netcdf library, which in turn is taken
from the HDF5 filter registration page.
* New errors are defined: NC_EFILTER and NC_ENOFILTER. The latter
is returned if an attempt is made to access an unknown filter.
* Internally, the dispatch table has been extended to add a function
to handle all of the filter functions.
* New, filter-related, tests were added to nc_test4.
* A new plugin was added to the plugins directory to help with testing.
Notes:
1. The shuffle and fletcher32 filters are not part of the multifilter system.
Misc. changes:
1. A debug module was added to libhdf5 to help catch error locations.
I see that there is no way to set CURLOPT_CONNECTTIMEOUT,
but there is support for CURLOPT_TIMEOUT.
So, accept the line 'HTTP.CONNECTTIMEOUT'
in .rc file to allow user to set CURLOPT_CONNECTTIMEOUT.
Some versions of some servers are returning malformed responses.
Make the library either handle them or gracefully fail.
The three server errors "fixed" here are as follows.
1. The attribute _NCProperties sometimes has a trailing nul character
in its value. Soln is to elide the nul(s).
2. Sometimes a DAP response has no data part, only a DMR.
Soln is to detect and return an error code instead of crashing.
3. Sometimes a server returns a redirection, but our current
openmagic() function was not following the redirect. Soln
is to follow redirects.
Also because of #2, I am temporarily making --disable-dap-remote-tests
be the default.
The comment states that prefix must end in '/', but the '/' is added in the function itself, so the prefix should *not* end in '/' and the comment is incorrect.
* For URL paths, the new approach essentially centralizes all information
in the URL into the "#mode=" fragment key and uses that value
to determine the dispatcher for (most) URLs.
* The new approach has the following steps:
1. canonicalize the path if it is a URL.
2. use the mode= fragment key to determine the dispatcher
3. if dispatcher still not determined, then use the mode flags
argument to nc_open/nc_create to determine the dispatcher.
4. if the path points to something readable, attempt to read the
magic number at the front, and use that to determine the dispatcher.
this case may override all previous cases.
* Misc changes.
1. Update documentation
2. Moved some unit tests from libdispatch to unit_test directory.
3. Fixed use of wrong #ifdef macro in test_filter_reg.c
[I think this may fix an previously reported esupport query].
Partially address: https://github.com/Unidata/netcdf-c/issues/1056
Currently, some of the entries in the dispatch table
are conditional'd on USE_NETCDF4.
As a step in upgrading the dispatch table for use
with user-defined tables, we remove that conditional.
This means that all dispatch tables must implement the
netcdf-4 specific functions even if only to make them
return NC_ENOTNC4. To simplify this, a set of default
functions are defined in libdispatch/dnotnc4.c to provide this
behavior. The file libdispatch/dnotnc3.c is also relevant to
this.
The primary fix is to modify the various dispatch tables to
remove the conditional and use the functions in
libdispatch/dnotnc4.c as appropriate. In practice, all of the
existing tables are prepared to handle this, so the only
real change is to remove the conditionals.
Misc. Unrelated fixes
1. Fix some annoying warnings in ncvalidator.
Notes:
1. This has not been tested with either pnetcdf or hdf4 enabled.
When those are enabled, it is possible that there are still
some conditionals that need to be fixed.
re: github issue #1425
The 'ncdump -v' command causes a constraint to be sent
to the opendap code (in libdap2). This is a separate path
from specifying the constraint via a URL.
This separate path encoded its constraint using code independent
of and duplicative of that provided by ncuri.c and this duplicate
code did not properly encode the constraint, which might include
square brackets.
Solution chosen here was to get rid of the duplicate code and
ensure that all URL escaping is performed in the ncuribuild function
in the ncuri.c file.
Also removed the use of the NEWESCAPE conditional in ncuri.c
because it is no longer needed.
re: https://github.com/Unidata/netcdf-c/issues/1388
1. Centralize calls to curl_global_init and curl_global_cleanup
to libdispatch/ddispatch.c
2. Make the above calls if options require curl: currently
any of DAP2, DAP4, or byterange.
3. Side issue: Fix obscure bug in mmapio.c involving non-persistent mmap.
re: https://github.com/Unidata/netcdf-c/issues/1373 (partial)
* Mark some global constants be const to indicate to make them easier to track.
* Hide direct access to the ncrc_globalstate behind a function call.
* Convert dispatch tables to constants (except the user defined ones)
This has some consequences in terms of function arguments needing to be marked
as const also.
* Remove some no longer needed global fields
* Aggregate all the globals in nclog.c
* Uniformly replace nc_sizevector{0,1} with NC_coord_{zero,one}
* Uniformly replace nc_ptrdffvector1 with NC_stride_one
* Remove some obsolete code
Priority: Low
re: issue https://github.com/Unidata/netcdf-c/issues/1329
HDF5 has the ability to programmatically define new filters,
as opposed to using HDF5_PLUGIN_PATH env variable.
This PR adds support for that feature.
Not clear how useful this is, though.
See docs/filters.md for details.
re: esupport (DVK-211460)
Turns out it was a typo in libdispatch/dauth.c
Fix is to Change:
HTTP.USERNAME -> HTTP.CREDENTIALS.USERNAME
and
HTTP.PASSWORD-> HTTP.CREDENTIALS.PASSWORD
So, fixed the following:
1. Forgot to check for NC_FORMATX_PNETCDF case
in one of the switches in NC_infermodel.
2. Accidentally turned on both the NC_64BIT_OFFSET
and the NC_64BIT_DATA mode flags.
re: issue https://github.com/Unidata/netcdf-c/issues/1278
re: issue https://github.com/Unidata/netcdf-c/issues/876
re: issue https://github.com/Unidata/netcdf-c/issues/806
* Major change to the handling of 8-byte parameters for nc_def_var_filter.
The old code was not well thought out.
* The new algorithm is documented in docs/filters.md.
* Added new utility file plugins/H5Zutil.c to support
* Modified plugins/H5Zmisc.c to use new algorithm
the new algorithm.
* Renamed include/ncfilter.h to include/netcdf_filter.h
and made it an installed header so clients can access the
new algorithm utility.
* Fixed nc_test4/tst_filterparser.c and nc_test4/test_filter_misc.c
to use the new algorithm
* libdap4/ fixes:
* d4swap.c has an error in the endian pre-processing such
that record counts were not being swapped correctly.
* d4data.c had an error in that checksums were being computed
after endian swapping rather than before.
* ocinitialize() was never being called, so xxdr bigendian handling
was never set correctly.
* Required adding debug statements to occompile
* Found and fixed memory leak in ncdump.c
Not tested:
* HDF4
* Pnetcdf
* parallel HDF5
re: issue https://github.com/Unidata/netcdf-c/issues/1251
Assume that you have the URL to a remote dataset
which is a normal netcdf-3 or netcdf-4 file.
This PR allows the netcdf-c to read that dataset's
contents as a netcdf file using HTTP byte ranges
if the remote server supports byte-range access.
Originally, this PR was set up to access Amazon S3 objects,
but it can also access other remote datasets such as those
provided by a Thredds server via the HTTPServer access protocol.
It may also work for other kinds of servers.
Note that this is not intended as a true production
capability because, as is known, this kind of access to
can be quite slow. In addition, the byte-range IO drivers
do not currently do any sort of optimization or caching.
An additional goal here is to gain some experience with
the Amazon S3 REST protocol.
This architecture and its use documented in
the file docs/byterange.dox.
There are currently two test cases:
1. nc_test/tst_s3raw.c - this does a simple open, check format, close cycle
for a remote netcdf-3 file and a remote netcdf-4 file.
2. nc_test/test_s3raw.sh - this uses ncdump to investigate some remote
datasets.
This PR also incorporates significantly changed model inference code
(see the superceded PR https://github.com/Unidata/netcdf-c/pull/1259).
1. It centralizes the code that infers the dispatcher.
2. It adds support for byte-range URLs
Other changes:
1. NC_HDF5_finalize was not being properly called by nc_finalize().
2. Fix minor bug in ncgen3.l
3. fix memory leak in nc4info.c
4. add code to walk the .daprc triples and to replace protocol=
fragment tag with a more general mode= tag.
Final Note:
Th inference code is still way too complicated. We need to move
to the validfile() model used by netcdf Java, where each
dispatcher is asked if it can process the file. This decentralizes
the inference code. This will be done after all the major new
dispatchers (PIO, Zarr, etc) have been implemented.
