Commit Graph

868 Commits

Author SHA1 Message Date
Julien Schueller
5537a60885 CMake: Add support for UNITY_BUILD 2024-01-12 10:18:29 +01:00
Ward Fisher
c1fb4b0bae
Merge pull request #2809 from ZedThree/silence-malloc-warnings
Silence conversion warnings from `malloc` arguments
2023-12-21 17:20:56 -07:00
Ward Fisher
2616e2c411
Merge pull request #2745 from e-kwsm/chmod-x
chore: unset executable flag
2023-12-11 17:28:46 -07:00
Ward Fisher
002e2869ab
Merge pull request #2691 from seanm/snprintf
sprintf -> snprintf
2023-12-11 15:46:51 -07:00
Sean McBride
4f15a9265e Removed a use of sprintf that required changing a function signature 2023-12-08 13:30:54 -05:00
Sean McBride
adc4dc1435 Replaced some sprintf with snprintf with aid of new variable containing size
One case required slightly complicated accounting of how much space is left in the buffer.
2023-12-08 13:30:38 -05:00
Sean McBride
dfc2ac7296 Replaced trivial uses of sprintf with snprintf
In all these cases the size of the buffer can be computed with sizeof.
2023-12-08 13:30:38 -05:00
Peter Hill
9fb3ab110f
Silence a couple of float conversion warnings in dumplib.c 2023-11-28 17:39:10 +00:00
Peter Hill
19027c77b9
Fix some other sign conversion warnings in dumplib 2023-11-28 17:38:38 +00:00
Peter Hill
653e09fd6d
Try to more consistently use size_t for nclistget index argument 2023-11-28 16:28:31 +00:00
Peter Hill
35ddd9ec01
Return int from internal sbuf_len function
This silences lots of warnings where the result is implicitly
converted to `int`
2023-11-27 15:10:30 +00:00
Peter Hill
d07dac918c
Silence conversion warnings from malloc arguments
Mostly just add an explicit cast when calling `malloc` and its
variants. Sometimes instead change the type of a local variable if
this would silence multiple warnings.
2023-11-24 18:20:52 +00:00
Peter Hill
763e54f8a1
Fix most float conversion warnings
Fixes ~200 out of ~240 `-Wfloat-conversion` warnings on gcc 13.2
2023-10-26 16:01:24 +01:00
Dennis Heimbigner
df3636b959 Mitigate S3 test interference + Unlimited Dimensions in NCZarr
This PR started as an attempt to add unlimited dimensions to NCZarr.
It did that, but this exposed significant problems with test interference.
So this PR is mostly about fixing -- well mitigating anyway -- test
interference.

The problem of test interference is now documented in the document docs/internal.md.
The solutions implemented here are also describe in that document.
The solution is somewhat fragile but multiple cleanup mechanisms
are provided. Note that this feature requires that the
AWS command line utility must be installed.

## Unlimited Dimensions.
The existing NCZarr extensions to Zarr are modified to support unlimited dimensions.
NCzarr extends the Zarr meta-data for the ".zgroup" object to include netcdf-4 model extensions. This information is stored in ".zgroup" as dictionary named "_nczarr_group".
Inside "_nczarr_group", there is a key named "dims" that stores information about netcdf-4 named dimensions. The value of "dims" is a dictionary whose keys are the named dimensions. The value associated with each dimension name has one of two forms
Form 1 is a special case of form 2, and is kept for backward compatibility. Whenever a new file is written, it uses format 1 if possible, otherwise format 2.
* Form 1: An integer representing the size of the dimension, which is used for simple named dimensions.
* Form 2: A dictionary with the following keys and values"
   - "size" with an integer value representing the (current) size of the dimension.
   - "unlimited" with a value of either "1" or "0" to indicate if this dimension is an unlimited dimension.

For Unlimited dimensions, the size is initially zero, and as variables extend the length of that dimension, the size value for the dimension increases.
That dimension size is shared by all arrays referencing that dimension, so if one array extends an unlimited dimension, it is implicitly extended for all other arrays that reference that dimension.
This is the standard semantics for unlimited dimensions.

Adding unlimited dimensions required a number of other changes to the NCZarr code-base. These included the following.
* Did a partial refactor of the slice handling code in zwalk.c to clean it up.
* Added a number of tests for unlimited dimensions derived from the same test in nc_test4.
* Added several NCZarr specific unlimited tests; more are needed.
* Add test of endianness.

## Misc. Other Changes
* Modify libdispatch/ncs3sdk_aws.cpp to optionally support use of the
   AWS Transfer Utility mechanism. This is controlled by the
   ```#define TRANSFER```` command in that file. It defaults to being disabled.
* Parameterize both the standard Unidata S3 bucket (S3TESTBUCKET) and the netcdf-c test data prefix (S3TESTSUBTREE).
* Fixed an obscure memory leak in ncdump.
* Removed some obsolete unit testing code and test cases.
* Uncovered a bug in the netcdf-c handling of big-endian floats and doubles. Have not fixed yet. See tst_h5_endians.c.
* Renamed some nczarr_tests testcases to avoid name conflicts with nc_test4.
* Modify the semantics of zmap\#ncsmap_write to only allow total rewrite of objects.
* Modify the semantics of zodom to properly handle stride > 1.
* Add a truncate operation to the libnczarr zmap code.
2023-09-26 16:56:48 -06:00
Eisuke Kawashima
d755c4ff32
chore: unset executable flag 2023-08-23 13:31:42 +09:00
Dennis Heimbigner
cdbf04956b Provide a single option to disable all network access and testing.
Add the option "--disable-network-access" (automake)
or "-DENABLE_NETWORK_ACCESS=OFF" (cmake).
When disabled, this option transitively disables all
network access capabilities and testing.
If set, this option implies the following:
* --disable-dap
* --disable-byterange
* --disable-s3

This PR answers a request for a feature from Ed Hartnett.

## Misc. Other changes
* Take the opportunity to clean up some old, unused options;
e.g. --enable-multifilters.
* Fix bug in using S3 urls.
2023-06-10 14:08:04 -06:00
Ward Fisher
5dedd76de9
Merge branch 'main' into ncdumptests.dmh 2023-05-16 11:22:15 -06:00
Dennis Heimbigner
49737888ca Improve S3 Documentation and Support
## Improvements to S3 Documentation
* Create a new document *quickstart_paths.md* that give a summary of the legal path formats used by netcdf-c. This includes both file paths and URL paths.
* Modify *nczarr.md* to remove most of the S3 related text.
* Move the S3 text from *nczarr.md* to a new document *cloud.md*.
* Add some S3-related text to the *byterange.md* document.

Hopefully, this will make it easier for users to find the information they want.

## Rebuild NCZarr Testing
In order to avoid problems with running make check in parallel, two changes were made:
1. The *nczarr_test* test system was rebuilt. Now, for each test.
any generated files are kept in a test-specific directory, isolated
from all other test executions.
2. Similarly, since the S3 test bucket is shared, any generated S3 objects
are isolated using a test-specific key path.

## Other S3 Related Changes
* Add code to ensure that files created on S3 are reclaimed at end of testing.
* Used the bash "trap" command to ensure S3 cleanup even if the test fails.
* Cleanup the S3 related configure.ac flag set since S3 is used in several places. So now one should use the option *--enable-s3* instead of *--enable-nczarr-s3*, although the latter is still kept as a deprecated alias for the former.
* Get some of the github actions yml to work with S3; required fixing various test scripts adding a secret to access the Unidata S3 bucket.
* Cleanup S3 portion of libnetcdf.settings.in and netcdf_meta.h.in and test_common.in.
* Merge partial S3 support into dhttp.c.
* Create an experimental s3 access library especially for use with Windows. It is enabled by using the options *--enable-s3-internal* (automake) or *-DENABLE_S3_INTERNAL=ON* (CMake). Also add a unit-test for it.
* Move some definitions from ncrc.h to ncs3sdk.h

## Other Changes
* Provide a default implementation of strlcpy and move this and similar defaults into *dmissing.c*.
2023-04-25 17:15:06 -06:00
Dennis Heimbigner
a6b0348e9d Fix some race conditions between some ncdump tests.
There are apparently some dependency conditions between ncdump/tst_nccopy4.sh and ncdump/tst_netcdf4.sh.
Fixed by creating a per-test directory into which all created intermediates are stored. Also created a test_ncdump.sh file to hold common code.

## Other Changes
* Remove some uses of strlcat from plugin-related code because strlcat is not always defined on some platforms and the plugin code generally should not rely on accessing libnetcdf.
* Cleanup the handling of test plugins.
2023-04-12 20:37:03 -06:00
Ward Fisher
c8b3b37b1a Merge branch 'dap4tests2.dmh' of https://github.com/DennisHeimbigner/netcdf-c 2023-04-11 16:42:32 -06:00
Ward Fisher
9459f92f1f
Merge branch 'main' into dap4tests1.dmh 2023-04-11 16:23:48 -06:00
Dennis Heimbigner
3765d86e46 "Simplify" XGetopt usage
When "getopt()" is not available, various of the netcdf-c utilities
use XGetopt instead. This occurs primarily when building under Window,
so the build changes are restricted to CMake.

This PR tries to isolate XGetopt.c to the libdispatch directory
and then builds the various utilities using this cliche:
````
IF(USE_X_GETOPT)
  SET(XGETOPTSRC "${CMAKE_CURRENT_SOURCE_DIR}/../libdispatch/XGetopt.c")
ENDIF()
````

This avoids the need to copy XGetopt.c to all the directories that
use it.
2023-04-09 13:10:41 -06:00
Dennis Heimbigner
5b42e382b0 Update to latest main 2023-04-04 18:37:20 -06:00
Dennis Heimbigner
fff025bfb8 update 2023-02-08 16:22:29 -07:00
Dennis Heimbigner
8f55cf31cf update 2023-02-08 16:17:31 -07:00
Dennis Heimbigner
ebf86ac637 update against main 2023-01-28 13:45:35 -07:00
Dennis Heimbigner
158c790ae5 Fix Memory Leak
re: PR https://github.com/Unidata/netcdf-c/pull/2584
re: PR https://github.com/Unidata/netcdf-c/pull/2596

Repaired a memory leak in *netcdf-c/ncdump/utils.c*. I think introduced
by PR 2584.

## Misc. Other Changes
* Fixed references to *netcdf-c/docs/byterange.dox* ->  *netcdf-c/docs/byterange.md* (PR 2596).
2023-01-26 13:11:25 -07:00
Ward Fisher
7d3d5f20c2 Fix an issue I introduced with make distcheck 2023-01-18 16:13:37 -07:00
Ward Fisher
94cad502b6 Add new test, tst_calendars_nc4.sh, to automake-based builds. 2023-01-18 15:14:28 -07:00
Stephen Herbener
4e7480f6b1 Moved the new ncdump_tst_calendars_nc4 test to the "USE_HDF5" section. 2023-01-18 11:00:12 -07:00
Stephen Herbener
5175de9df0 Modifications to enable the use of variable length string attributes for both
"units" and "calendar".
2023-01-09 16:36:49 -07:00
Stephen Herbener
a2bcb9d03c Added an ncdump -t calendars test using variable length string
attributes ("calendar" and "units").
2023-01-08 15:58:20 -07:00
Dennis Heimbigner
835b81a285 Cleanup DAP4 testing
NOTE: This PR should not be included in 4.9.1 since additional
DAP4 related PRs will be forthcoming.

This PR makes major changes to libdap4 and dap4_test driven by changes to TDS.

* Enable DAP4
* Clean up the test input files and the test baseline comparison files. This entails:
    * Remove a multitude of unused test input and baseline data files; among them are dap4_test/: daptestfiles, dmrtestfiles, nctestfiles, and misctestfiles.
    * Define a canonical set of test input files and record in dap4_test/cdltestfiles.
    * Use the cdltestfiles to generate the .nc test inputs. This set of .nc files is then moved to the d4ts (DAP4 test server) war file in the tds repository. This set then becomes the canonical set of DAP4 test sources.
    * Scrape d4ts to obtain copies of the raw streams of DAP4 encoded data. The .dmr and .dap streams are then stored in dap4_test/rawtestfiles.
    * Disable some remote server tests until those servers are fixed.
* Add an option to ncdump (-XF) that forces the type of the _FillValue attribute; this is primarily to simplify testing of fill mismatch.
* Minor bug fixes to ncgen.
* Changes to libdap4:
    * Replace old checksum hack with the dap4.checksum flag.
    * Support the dap4.XXX controls.
    * Cleanup _FillValue handling, especially var-attribute type mismatches.
    * Fix enum handling based on changes to netcdf-java.
* Changes to dap4_test:
    * Add getopt support to various test support programs.
    * Remove unneeded shell scripts.
    * Add new scripts: test_curlopt.sh
2022-11-13 13:15:11 -07:00
Dennis Heimbigner
9f848c9e53 Fix race condition in ncdump (and other) tests.
re: Issue https://github.com/Unidata/netcdf-c/issues/2551

Ryan May identified the use of a common scratch file (tmp.cdl)
across multiple test shell scripts in ncdump directory
and the nczarr_test directory.
This sometimes causes errors because of race conditions
between those scripts.

I renamed those common files to avoid the race condition.  I
also did some further checking and found some additional,
similar conflicts and fixed those. Also did some minor cleanup
of unused files.

Tests fixed:
ncdump: run_back_comp_tests.sh tst_bom.sh tst_nccopy4.sh tst_nccopy5.sh
nczarr_test: git df master -- run_nccopyz.sh run_nczarr_fill.sh run_scalar.sh
2022-11-08 20:12:38 -07:00
Ward Fisher
6befdad33a Added additional dependencies. 2022-09-28 11:32:57 -06:00
Ward Fisher
96b285922b Added a dependency to tst_nans to nccopy4 2022-09-28 10:47:40 -06:00
Ward Fisher
c73967b0c2 Correct nccopy4 dependency on tst_fillbug. 2022-09-28 10:38:35 -06:00
Dennis Heimbigner
1a45ee025f Fix some addtional errors in NCZarr
re: Issue https://github.com/Unidata/netcdf-c/issues/2502

H/T Charlie Zender

* Fix NCZarr handling of endianness value NC_ENDIAN_NATIVE. This now matches how it is handled in libhdf5
* Fix NCZarr handling of char typed attribute with value "". This now matches how it is handled in libhdf5
* Add test for various char attribute values
* Change the mapping of NC_CHAR and NC_STRING to dtype; requires changing some test files also.
* Optimize the testing for NC_ENOTBUILT in NC_open.
* Turn off debugging left on accidentally
* Fix memory leak in tst_pnetcdf.c
* Fix blosc test
2022-09-09 14:25:24 -06:00
Ward Fisher
ba37c0af9f
Merge branch 'main' into enumdfalt.dmh 2022-07-26 15:23:40 -06:00
Dennis Heimbigner
65fd9fe1a5 Provide a default enum const when fill value does not match any enum const.
re: https://github.com/Unidata/netcdf-c/issues/982

It is possible to define an enum type that has no enum constant
with value zero. However, HDF5 has a default fill value of zero
that it used to fill all chunks. In the event that this situation
occurs, ncdump, say, will fail because there is no enum const
to print for the value zero.

The solution is to create a special enum constant called "_UNDEFINED"
that has the value zero. It is only used in the case that there is
no constant in the enum that already covers zero.

A test case is added in netcdf-c/ncdump to validate this solution.

Note: the changes occur primarily in libsrc4, so they also work for NCZarr.
2022-07-17 14:32:31 -06:00
Dennis Heimbigner
8b0e1134b4 Ensure that netcdf_json.h does not interfere with ncjson.
re: Issue https://github.com/Unidata/netcdf-c/issues/2419

There are effectively two json subsystems in netcdf-c.
1. ncjson.[ch] in libnetcdf
2. netcdf_json.h for use by plugins so they can be built without need
   for libnetcdf.

The netcdf_json.h file is constructed from the concatenation of
ncjson.h plus ncjson.c. It turned out that in doing this, I was
leaving some symbols externally visible so that if, for some
reason, a plugin was built and needed libnetcdf, then symbol
conflicts arose.

The solution is to prefix the declarations in ncjson.[ch] with a
macro (OPTSTATIC) that can be resolved to either nothing or to
"static". Then in netcdf_json.h, it resolves to "static" and
prevents the symbol conflicts.

Note that netcdf_json.h is constructed once in
netcdf-c/include/Makefile.am with the rule named
"makepluginjson". This means that it is included in the
distribution. However, this also means that if ncjson.[ch] is
changed, then it is necessary to invoke makepluginjson
explicitly to rebuild netcdf_json.h
2022-07-05 22:03:52 -06:00
Dennis Heimbigner
abba5c383b Fix errors:
1. I accidentally used ncrc_initialize instead of nc_initialize.
2. Change HTTP.CAINFO to HTTP.SSL.CAINFO
2022-06-20 14:09:05 -06:00
Dennis Heimbigner
aabbdbf64c Make public a limited API for programmatic access to internal .rc tables
re: https://github.com/Unidata/netcdf-c/issues/2337
re: https://github.com/Unidata/netcdf-c/issues/2407

Add two functions to netcdf.h to allow programs to get/set
selected entries into the internal .rc tables. This should fix
the above issues by allowing HTTP.CAINFO to be set to the
certificates directory.  Note that the changes should be
performed as early as possible in the program because some of
the .rc table entries may get cached internally and changing the
entry after that caching occurs may have no effect.

The new signatures are as follows:

1. Get the value of a simple .rc entry of the form "key=value".
Note that caller must free the returned value, which might be NULL.
````
char* nc_rc_get(char* const * key);

@param key table entry key
@return value if .rc table has entry of the form key=value
@return NULL if no such entry is found.
````

2. Insert/Overwrite the specified key=value pair in the .rc table.
````
int nc_rc_set(const char* key, const char* value);

@param key table entry key -- may not be NULL
@param value table entry value -- may not be NULL
@return NC_NOERR if no error
@return NC_EINVAL if error
````

Addendum:

re: https://github.com/Unidata/netcdf-c/issues/2407

Modify dhttp.c to use the .rc entry HTTP.CAINFO if defined.
2022-06-17 14:35:12 -06:00
Greg Sjaardema
f89dcb9dfa
Initialize potentially uninitialized variable
If `cvtoptions.pathkind` is true, then `canon` will not be initialized and it is accessed at line 279.
2022-06-07 14:28:01 -06:00
Dennis Heimbigner
89f7b64442 Merge branch 'master' into install.dmh 2022-05-27 15:40:26 -06:00
Ward Fisher
6a935c6812
Merge pull request #2304 from Alexander-Barth/main
Include getopt.h if HAVE_GETOPT_H is defined
2022-05-27 09:08:48 -06:00
Dennis Heimbigner
8037b45f71 typo 2022-05-19 22:43:08 -06:00
Dennis Heimbigner
e05f5c36a8 Merge master 2022-05-17 15:11:31 -06:00
Dennis Heimbigner
7b09290a3a Improve filter installation process to avoid use of an extra shell script
re: https://github.com/Unidata/netcdf-c/issues/2338
re: https://github.com/Unidata/netcdf-c/issues/2294

In issue https://github.com/Unidata/netcdf-c/issues/2338,
Ed Hartnett suggested a better way to install filters to a user
defined location -- for Automake, anyway.

This PR implements that suggestion. It turns out to be more
complicated than it appears, so there are fair number of changes;
mostly to shell scripts. Most of the change is in plugins/Makefile.am.

NOTE: this PR still does NOT address the use of HDF5_PLUGIN_PATH
as the default; this turns out to be complex when dealing with NCZarr.
So this will be addressed in a subsequent post 4.9.0 PR.

## Misc. Changes
1. Record the occurrences of incomplete codecs in libnczarr so that
   they can be included in _Codecs attribute correctly. This allows
   users to see what missing filters are referenced in the Zarr file.
   Primarily affects libnczarr/zfilter.[ch]. Also required creating a
   new no-effect filter: H5Zunknown.c.
2. Move the unknown filter test to a separate test file.
3. Incorporates PR https://github.com/Unidata/netcdf-c/pull/2343
2022-05-14 16:05:48 -06:00
Alexander Barth
e7b21b5744
Merge branch 'Unidata:main' into main 2022-05-13 14:16:15 +02:00
Dennis Heimbigner
8eb0712eb6 final1 2022-05-09 14:45:06 -06:00
Dennis Heimbigner
53890fd3a0 Fix distcheck problems
re: https://github.com/Unidata/netcdf-c/issues/2342
This PR replaces PR https://github.com/Unidata/netcdf-c/pull/2342

This PR extends the distcheck corrections in PR
https://github.com/Unidata/netcdf-c/pull/2342.  That original PR
exposed some errors in the file naming in the plugins and
nczarr_test directories.  This PR corrects those problems and
should be used instead of https://github.com/Unidata/netcdf-c/pull/2342

Ed Hartnett's suggestion about how to install the plugins in the
user specified directory will be addressed in a subsequent PR.
2022-05-09 12:10:53 -06:00
Dennis Heimbigner
f897b458ea Fix szip handling 2022-04-30 19:06:01 -06:00
Dennis Heimbigner
a8aa6e3db3 Remove debug 2022-04-29 14:38:18 -06:00
Dennis Heimbigner
65038335bf Two fixes for the price of one!
## Include <getopt.h> in various utilities
re: https://github.com/Unidata/netcdf-c/issues/2303
As noted, some utilities are using getopt() without including
getopt.h, so add as needed.

## Turn off run_diskless2.sh when ENABLE_PARALLEL is true
re: https://github.com/Unidata/netcdf-c/issues/2315
Ed notes that this test hangs when running parallel.  The test
is attempting to create a very large in-memory file, which is
the proximate cause. But no idea what's the underlying cause.
2022-04-28 15:51:20 -06:00
Alexander Barth
dac997c087
Include getopt.h if HAVE_GETOPT_H is defined 2022-04-25 11:23:35 +02:00
Ward Fisher
c0f319de3c
Merge branch 'main' into mingw-w64-pwd 2022-04-11 10:39:10 -06:00
Ward Fisher
3446aa0c13 Merge branch 'winutf8.dmh' of https://github.com/DennisHeimbigner/netcdf-c into gh2222.wif 2022-04-05 10:46:22 -06:00
Ward Fisher
cd0f1690e8
Merge pull request #2245 from DennisHeimbigner/filterenhance.dmh 2022-03-21 16:45:27 -06:00
Ward Fisher
5856b8ed9c Merge branch 'mingw-w64-name_path' of https://github.com/mjwoods/netcdf-c into gh2104.wif 2022-03-14 16:11:18 -06:00
Dennis Heimbigner
150e19cf87 Fix new LGTM errors 2022-03-14 13:50:41 -06:00
Dennis Heimbigner
3ffe7be446 Enhance/Fix filter support
re: Discussion https://github.com/Unidata/netcdf-c/discussions/2214

The primary change is to support so-called "standard filters".
A standard filter is one that is defined by the following
netcdf-c API:
````
int nc_def_var_XXX(int ncid, int varid, size_t nparams, unsigned* params);
int nc_inq_var_XXXX(int ncid, int varid, int* usefilterp, unsigned* params);
````
So for example, zstandard would be a standard filter by defining
the functions *nc_def_var_zstandard* and *nc_inq_var_zstandard*.

In order to define these functions, we need a new dispatch function:
````
int nc_inq_filter_avail(int ncid, unsigned filterid);
````
This function, combined with the existing filter API can be used
to implement arbitrary standard filters using a simple code pattern.
Note that I would have preferred that this function return a list
of all available filters, but HDF5 does not support that functionality.

So this PR implements the dispatch function and implements
the following standard functions:
    + bzip2
    + zstandard
    + blosc
Specific test cases are also provided for HDF5 and NCZarr.
Over time, other specific standard filters will be defined.

## Primary Changes
* Add nc_inq_filter_avail() to netcdf-c API.
* Add standard filter implementations to test use of *nc_inq_filter_avail*.
* Bump the dispatch table version number and add to all the relevant
   dispatch tables (libsrc, libsrcp, etc).
* Create a program to invoke nc_inq_filter_avail so that it is accessible
  to shell scripts.
* Cleanup szip support to properly support szip
  when HDF5 is disabled. This involves detecting
  libsz separately from testing if HDF5 supports szip.
* Integrate shuffle and fletcher32 into the existing
  filter API. This means that, for example, nc_def_var_fletcher32
  is now a wrapper around nc_def_var_filter.
* Extend the Codec defaulting to allow multiple default shared libraries.

## Misc. Changes
* Modify configure.ac/CMakeLists.txt to look for the relevant
  libraries implementing standard filters.
* Modify libnetcdf.settings to list available standard filters
  (including deflate and szip).
* Add CMake test modules to locate libbz2 and libzstd.
* Cleanup the HDF5 memory manager function use in the plugins.
* remove unused file include//ncfilter.h
* remove tests for the HDF5 memory operations e.g. H5allocate_memory.
* Add flag to ncdump to force use of _Filter instead of _Deflate
  or _Shuffle or _Fletcher32. Used for testing.
2022-03-14 12:39:37 -06:00
Sean McBride
bb03191356 Fixed Clang -Wstrict-prototypes warnings 2022-03-01 23:21:24 -05:00
Ward Fisher
7c113cfae4 Merge branch 'h5align.dmh' of https://github.com/DennisHeimbigner/netcdf-c into gh2206.wif 2022-03-01 09:49:13 -08:00
Dennis Heimbigner
9b7202bf06 Explicitly disallow variable length type compression
re: https://github.com/Unidata/netcdf-c/issues/2189

Compression of a variable whose type is variable length
fails for all current filters. This is because at some point,
the compression buffer will contain pointers to data instead
of the actual data. Compression of pointers of course is meaningless.

The PR changes the behavior of nc_def_var_filter so that it will
fail with error NC_EFILTER if an attempt is made to add a filter
to a variable whose type is variable-length.

A variable is variable-length if it is of type string or VLEN
or transitively (via a compound type) contains a string or VLEN.

Also added a test case for this.

## Misc Changes
1. Turn off a number of debugging statements
2022-02-19 16:47:31 -07:00
Dennis Heimbigner
36102e3c32 Improve UTF8 Support On Windows
re: Issue https://github.com/Unidata/netcdf-c/issues/2190

The primary purpose of this PR is to improve the utf8 support
for windows. This is persuant to a change in Windows that
supports utf8 natively (almost). The almost means that it is
still utf16 internally and the set of characters representable
by utf8 is larger than those representable by utf16.

This leaves open the question in the Issue about handling
the Windows 1252 character set.

This required the following changes:

1. Test the Windows build and major version in order to see if
   native utf8 is supported.
2. If native utf8 is supported, Modify dpathmgr.c to call the 8-bit
   version of the windows fopen() and open() functions.
3. In support of this, programs that use XGetOpt (Windows versions)
   need to get the command line as utf8 and then parse to
   arc+argv as utf8. This requires using a homegrown command line parser
   named XCommandLineToArgvA.
4. Add a utility program called "acpget" that prints out the
   current Windows code page and locale.

Additionally, some technical debt was cleaned up as follows:

1. Unify all the places which attempt to read all or a part
   of a file into the dutil.c#NC_readfile code.
2. Similary unify all the code that creates temp files into
   dutil.c#NC_mktmp code.
3. Convert almost all remaining calls to fopen() and open()
   to NCfopen() and NCopen3(). This is to ensure that path management
   is used consistently. This touches a number of files.
4. extern->EXTERNL as needed to get it to work under Windows.
2022-02-08 20:53:30 -07:00
Ward Fisher
0eb753a86e Adding a missing reference file. 2022-02-01 11:48:27 -07:00
Ward Fisher
dcf3b3be65 Adding a missing file to make dist. 2022-02-01 11:46:01 -07:00
Dennis Heimbigner
f3e711e2b8 Add support for setting HDF5 alignment property when creating a file
re: https://github.com/Unidata/netcdf-c/issues/2177
re: https://github.com/Unidata/netcdf-c/pull/2178

Provide get/set functions to store global data alignment
information and apply it when a file is created.

The api is as follows:
````
int nc_set_alignment(int threshold, int alignment);
int nc_get_alignment(int* thresholdp, int* alignmentp);
````

If defined, then for every file created opened after the call to
nc_set_alignment, for every new variable added to the file, the
most recently set threshold and alignment values will be applied
to that variable.

The nc_get_alignment function return the last values set by
nc_set_alignment.  If nc_set_alignment has not been called, then
it returns the value 0 for both threshold and alignment.

The alignment parameters are stored in the NCglobalstate object
(see below) for use as needed. Repeated calls to nc_set_alignment
will overwrite any existing values in NCglobalstate.

The alignment parameters are applied in libhdf5/hdf5create.c
and libhdf5/hdf5open.c

The set/get alignment functions are defined in libsrc4/nc4internal.c.

A test program was added as nc_test4/tst_alignment.c.

## Misc. Changes Unrelated to Alignment

* The NCRCglobalstate type was renamed to NCglobalstate to
  indicate that it represented more general global state than
  just .rc data.  It was also moved to nc4internal.h.  This led
  to a large number of small changes: mostly renaming. The
  global state management functions were moved to nc4internal.c.

* The global chunk cache variables have been moved into
  NCglobalstate.  As warranted, other global state will be moved
  as well.

* Some misc. problems with the nczarr performance tests were corrected.
2022-01-29 15:27:52 -07:00
Dennis Heimbigner
446348ed18 Add complete bitgroom support to NCZarr
re: PR https://github.com/Unidata/netcdf-c/pull/2088
re: PR https://github.com/Unidata/netcdf-c/pull/2130
replaces: https://github.com/Unidata/netcdf-c/pull/2140

Changes:
* Add NCZarr-specific quantize functions to the dispatch table.
* Copy (modified) quantize code from libhdf5 to NCZarr
* Add quantize invocation to zvar.c
* Add support for _QuantizeBitgroomNumberOfSignificantDigits
and _QuantizeGranularBitgroomNumberOfSignificantDigits to ncgen.
* Modify nc_test4/tst_quantize.c to allow it to be used both for hdf5
  and for nczarr.
* Make dap4 properly handle quantize functions in dispatch table.
* Add quantize attribute support to ncgen.

Other changes:
* Caught and fixed some S3 problems
* Fixed some nczarr fillvalue problems.
* Fixed some nczarr cache problems.
* Cleanup some flaws in libdispatch/dinfermodel.c
* Allow byterange requests to S3 be readable by dinfermodel.c/check_file_type
* Remove the libnczarr ztracedispatch code (big change).
2022-01-24 15:22:24 -07:00
Ward Fisher
1666f80701
Merge pull request #2145 from oxelson/docs
Docs migration
2022-01-19 15:46:20 -07:00
Ward Fisher
978a99bbea
Merge branch 'main' into vlenfix.dmh 2022-01-13 16:31:34 -07:00
Dennis Heimbigner
d06938fd1d 1. Fix an additional flaw in fill_value handling where non-atomic default values were not properly being handled.
2. Rename the NC4_inq_any_type to NC_inq_any_type
3. Fix performance test cases affected by this PR.
2022-01-10 22:26:19 -07:00
Milton Woods
b33a6348f1
Merge branch 'main' into mingw-w64-strcasecmp 2022-01-11 10:45:15 +11:00
Dennis Heimbigner
11547ffd29 1. Fix an additional flaw in fill_value handling where non-atomic default values were not properly being handled.
2. Rename the NC4_inq_any_type to NC_inq_any_type
2022-01-10 15:27:16 -07:00
Dennis Heimbigner
8b9253fef2 Fix various problem around VLEN's
re: https://github.com/Unidata/netcdf-c/issues/541
re: https://github.com/Unidata/netcdf-c/issues/1208
re: https://github.com/Unidata/netcdf-c/issues/2078
re: https://github.com/Unidata/netcdf-c/issues/2041
re: https://github.com/Unidata/netcdf-c/issues/2143

For a long time, there have been known problems with the
management of complex types containing VLENs.  This also
involves the string type because it is stored as a VLEN of
chars.

This PR (mostly) fixes this problem. But note that it adds new
functions to netcdf.h (see below) and this may require bumping
the .so number.  These new functions can be removed, if desired,
in favor of functions in netcdf_aux.h, but netcdf.h seems the
better place for them because they are intended as alternatives
to the nc_free_vlen and nc_free_string functions already in
netcdf.h.

The term complex type refers to any type that directly or
transitively references a VLEN type. So an array of VLENS, a
compound with a VLEN field, and so on.

In order to properly handle instances of these complex types, it
is necessary to have function that can recursively walk
instances of such types to perform various actions on them.  The
term "deep" is also used to mean recursive.

At the moment, the two operations needed by the netcdf library are:
* free'ing an instance of the complex type
* copying an instance of the complex type.

The current library does only shallow free and shallow copy of
complex types. This means that only the top level is properly
free'd or copied, but deep internal blocks in the instance are
not touched.

Note that the term "vector" will be used to mean a contiguous (in
memory) sequence of instances of some type. Given an array with,
say, dimensions 2 X 3 X 4, this will be stored in memory as a
vector of length 2*3*4=24 instances.

The use cases are primarily these.

## nc_get_vars
Suppose one is reading a vector of instances using nc_get_vars
(or nc_get_vara or nc_get_var, etc.).  These functions will
return the vector in the top-level memory provided.  All
interior blocks (form nested VLEN or strings) will have been
dynamically allocated.

After using this vector of instances, it is necessary to free
(aka reclaim) the dynamically allocated memory, otherwise a
memory leak occurs.  So, the recursive reclaim function is used
to walk the returned instance vector and do a deep reclaim of
the data.

Currently functions are defined in netcdf.h that are supposed to
handle this: nc_free_vlen(), nc_free_vlens(), and
nc_free_string().  Unfortunately, these functions only do a
shallow free, so deeply nested instances are not properly
handled by them.

Note that internally, the provided data is immediately written so
there is no need to copy it. But the caller may need to reclaim the
data it passed into the function.

## nc_put_att
Suppose one is writing a vector of instances as the data of an attribute
using, say, nc_put_att.

Internally, the incoming attribute data must be copied and stored
so that changes/reclamation of the input data will not affect
the attribute.

Again, the code inside the netcdf library does only shallow copying
rather than deep copy. As a result, one sees effects such as described
in Github Issue https://github.com/Unidata/netcdf-c/issues/2143.

Also, after defining the attribute, it may be necessary for the user
to free the data that was provided as input to nc_put_att().

## nc_get_att
Suppose one is reading a vector of instances as the data of an attribute
using, say, nc_get_att.

Internally, the existing attribute data must be copied and returned
to the caller, and the caller is responsible for reclaiming
the returned data.

Again, the code inside the netcdf library does only shallow copying
rather than deep copy. So this can lead to memory leaks and errors
because the deep data is shared between the library and the user.

# Solution

The solution is to build properly recursive reclaim and copy
functions and use those as needed.
These recursive functions are defined in libdispatch/dinstance.c
and their signatures are defined in include/netcdf.h.
For back compatibility, corresponding "ncaux_XXX" functions
are defined in include/netcdf_aux.h.
````
int nc_reclaim_data(int ncid, nc_type xtypeid, void* memory, size_t count);
int nc_reclaim_data_all(int ncid, nc_type xtypeid, void* memory, size_t count);
int nc_copy_data(int ncid, nc_type xtypeid, const void* memory, size_t count, void* copy);
int nc_copy_data_all(int ncid, nc_type xtypeid, const void* memory, size_t count, void** copyp);
````
There are two variants. The first two, nc_reclaim_data() and
nc_copy_data(), assume the top-level vector is managed by the
caller. For reclaim, this is so the user can use, for example, a
statically allocated vector. For copy, it assumes the user
provides the space into which the copy is stored.

The second two, nc_reclaim_data_all() and
nc_copy_data_all(), allows the functions to manage the
top-level.  So for nc_reclaim_data_all, the top level is
assumed to be dynamically allocated and will be free'd by
nc_reclaim_data_all().  The nc_copy_data_all() function
will allocate the top level and return a pointer to it to the
user. The user can later pass that pointer to
nc_reclaim_data_all() to reclaim the instance(s).

# Internal Changes
The netcdf-c library internals are changed to use the proper
reclaim and copy functions.  It turns out that the places where
these functions are needed is quite pervasive in the netcdf-c
library code.  Using these functions also allows some
simplification of the code since the stdata and vldata fields of
NC_ATT_INFO are no longer needed.  Currently this is commented
out using the SEPDATA \#define macro.  When any bugs are largely
fixed, all this code will be removed.

# Known Bugs

1. There is still one known failure that has not been solved.
   All the failures revolve around some variant of this .cdl file.
   The proximate cause of failure is the use of a VLEN FillValue.
````
        netcdf x {
        types:
          float(*) row_of_floats ;
        dimensions:
          m = 5 ;
        variables:
          row_of_floats ragged_array(m) ;
              row_of_floats ragged_array:_FillValue = {-999} ;
        data:
          ragged_array = {10, 11, 12, 13, 14}, {20, 21, 22, 23}, {30, 31, 32},
                         {40, 41}, _ ;
        }
````
When a solution is found, I will either add it to this PR or post a new PR.

# Related Changes

* Mark nc_free_vlen(s) as deprecated in favor of ncaux_reclaim_data.
* Remove the --enable-unfixed-memory-leaks option.
* Remove the NC_VLENS_NOTEST code that suppresses some vlen tests.
* Document this change in docs/internal.md
* Disable the tst_vlen_data test in ncdump/tst_nccopy4.sh.
* Mark types as fixed size or not (transitively) to optimize the reclaim
  and copy functions.

# Misc. Changes

* Make Doxygen process libdispatch/daux.c
* Make sure the NC_ATT_INFO_T.container field is set.
2022-01-08 18:30:00 -07:00
Dennis Heimbigner
43f2e51112 Fix new LGTM alerts 2021-12-23 23:10:44 -07:00
Dennis Heimbigner
9380790ea8 Support MSYS2/Mingw platform
re:

The current netcdf-c release has some problems with the mingw platform
on windows. Mostly they are path issues.

Changes to support mingw+msys2:
-------------------------------
* Enable option of looking into the windows registry to find
  the mingw root path. In aid of proper path handling.
* Add mingw+msys as a specific platform in configure.ac and move testing
  of the platform to the front so it is available early.
* Handle mingw X libncpoco (dynamic loader) properly even though
  mingw does not yet support it.
* Handle mingw X plugins properly even though mingw does not yet support it.
* Alias pwd='pwd -W' to better handle paths in shell scripts.
* Plus a number of other minor compile irritations.
* Disallow the use of multiple nc_open's on the same file for windows
  (and mingw) because windows does not seem to handle these properly.
  Not sure why we did not catch this earlier.
* Add mountpoint info to dpathmgr.c to help support mingw.
* Cleanup dpathmgr conversions.

Known problems:
---------------
* I have not been able to get shared libraries to work, so
  plugins/filters must be disabled.
* There is some kind of problem with libcurl that I have not solved,
  so all uses of libcurl (currently DAP+Byterange) must be disabled.

Misc. other fixes:
------------------
* Cleanup the relationship between ENABLE_PLUGINS and various other flags
  in CMakeLists.txt and configure.ac.
* Re-arrange the TESTDIRS order in Makefile.am.
* Add pseudo-breakpoint to nclog.[ch] for debugging.
* Improve the documentation of the path manager code in ncpathmgr.h
* Add better support for relative paths in dpathmgr.c
* Default the mode args to NCfopen to include "b" (binary) for windows.
* Add optional debugging output in various places.
* Make sure that everything builds with plugins disabled.
* Fix numerous (s)printf inconsistencies betweenb the format spec
  and the arguments.
2021-12-23 22:18:56 -07:00
Dennis Heimbigner
73caeb674d Cleanup the CMake inter-test dependencies
The ncdump test set has a number of inter-test dependencies
that are not properly established in ncdump/CMakeLists.txt.

So this PR attempts to:
1. reorder the tests
2. change tests in CMakeLists.txt from build_bin_test_no_prefix to add_bin_test_no_prefix so they get executed

Plus a couple of minor bug fixes.
1. Change ENABLE_NC4 => ENABLE_HDF5 in github action.
2. fix a memory error in findtestserver.c.in
3. fix bug in ncdap_tests/tst_urls.sh
4. fix netcdf file name bug in tst_netcdf4_4.sh
2021-12-20 15:13:08 -07:00
Jennifer Oxelson
a11349482c Docs migration 2021-11-11 10:47:49 -07:00
Dennis Heimbigner
55a2643cac Fix a number of OS specific bugs
1. Issue https://github.com/Unidata/netcdf-c/issues/2043
   * FreeBSD build fails because of conflicts in defining the fileno() function. So removed all extern declarations of fileno.

2. Issue https://github.com/Unidata/netcdf-c/issues/2124
   * There were a couple of problems here.
     * I was conflating msys with mingw and they need separate handling of paths. So treat mingw like windows.
     * memio.c was not always writing the full content of the memory to file. Untested fix by properly accounting for zero size writes.
     * Fix bug when skipping white space in tst_xcache.c

3. Issue https://github.com/Unidata/netcdf-c/pull/2105
   * On MINGW, bash and other POSIX utilities use a mounted root directory,
     but executables compiled for Windows do not recognise the mount point.
     Ensure that Windows paths are used in tests of Windows executables.

4. Issue https://github.com/Unidata/netcdf-c/issues/2132
   * Apparently the Intel C compiler on OSX defines isnan etc.
     So disable declaration in dutil.c under that condition.

5. Fix and re-enable test_rcmerge.sh by allowing override of where to
   look for .rc files

6. CMakeLists.txt suppresses certain ncdump directory tests because of differences in printing floats/doubles.
   * Extend the list to include those that also fail under mingw.
   * Suppress the mingw tests in ncdump/Makefile.am
2021-11-03 12:49:54 -06:00
Dennis Heimbigner
f6e25b695e Fix additional S3 support issues
re: https://github.com/Unidata/netcdf-c/issues/2117
re: https://github.com/Unidata/netcdf-c/issues/2119

* Modify libsrc to allow byte-range reading of netcdf-3 files in private S3 buckets; this required using the aws sdk. Also add a test case.
* The aws sdk can sometimes cause problems if the Awd::ShutdownAPI function is not called. So at optional atexit() support to ensure it is called. This is disabled for Windows.
* Add documentation to nczarr.md on how to build and use the aws sdk under windows. Currently it builds, but testing fails.
* Switch testing from stratus to the Unidata bucket on S3.
* Improve support for the s3: url protocol.
* Add a s3 specific utility code file: ds3util.c
* Modify NC_infermodel to attempt to read the magic number of byte-ranged files in S3.

## Misc.

* Move and rename the core S3 SDK wrapper code (libnczarr/zs3sdk.cpp) to libdispatch since it now used in libsrc as well as libnczarr.
* Add calls to nc_finalize in the utilities in case atexit is disabled.
* Add header only json parser to the distribution rather than as a built source.
2021-10-29 20:06:37 -06:00
Dennis Heimbigner
289103d2b1 Merge branch 'master' into zarrs3.dmh 2021-10-07 15:10:03 -06:00
Milton Woods
2da66c641e Revert "Replace pwd by $PWDCMD after test_common.sh is sourced"
This reverts commit 8665d7f866e67bd96a634bcc4968b9faba8c7d3c.
2021-10-03 09:55:17 +11:00
Milton Woods
9ec281a55a Replace pwd by $PWDCMD after test_common.sh is sourced 2021-10-03 09:55:17 +11:00
Milton Woods
02c92a5c4f Disable bash path conversions in testpathcvt.sh on mingw 2021-10-03 09:55:17 +11:00
Ward Fisher
e763e6caf1
Merge pull request #2109 from DennisHeimbigner/ncgenenum.dmh
Fix handling of enum constants nested in compound types.
2021-10-01 17:08:45 -05:00
Ward Fisher
7ec0ac0a08
Merge branch 'main' into mingw-w64-strcasecmp 2021-10-01 17:07:37 -05:00
Dennis Heimbigner
6b69b9c52c Significantly Improve Amazon S3 Cloud Storage Support
## S3 Related Fixes

* Add comprehensive support for specifying AWS profiles to provide access credentials.
* Parse the files "~/.aws/config" and "~/.aws/credentials to provide credentials for the HDF5 ROS3 driver and to locate default region.
* Add a function to obtain the currently active S3 credentials. The search rules are defined in docs/nczarr.md.
* Provide documentation for the new features.
* Modify the struct NCauth (in include/ncauth.h) to replace specific S3 credentials with a profile name.
* Add a unit test to test the operation of profile and credentials management.
* Add support for URLS of the form "s3://<bucket>/<key>"; this requires obtaining a default region.
* Allows the specification of profile and/or region in a URL of the form "#mode=nczarr,...&aws.region=...&aws.profile=..."

## Misc. Fixes

* Move the ezxml code to libdispatch so that it can be used both by DAP4 and nczarr.
* Modify nclist to provide a deep clone operation.
* Modify ncuri to provide a deep clone operation.
* Modify the .rc file format to allow the specification of a path to be tested when looking for an entry in the .rc file.
* Ensure that the NC_rcload function is called.
* Modify nchttp to support setting request headers.
2021-09-27 18:36:33 -06:00
Dennis Heimbigner
72d6894b80 Fix handling of enum constants nested in compound types.
re: Issue https://github.com/Unidata/netcdf-c/issues/2108

Fix ncgen to properly locate a matching enum type when it encounters
a reference to an enum constant. Add test cases.
2021-09-12 18:03:57 -06:00
Edward Hartnett
0ce463761c
Merge branch 'main' into ejh_quantize_2 2021-09-07 10:44:45 -06:00
Milton Woods
4fa91d8241 Use strcasecmp definitions from config.h 2021-09-05 17:17:30 +10:00
Milton Woods
2a66599276 Use canonical path to derive name of dataset 2021-09-04 10:31:25 +10:00
Dennis Heimbigner
11fe00ea05 Add filter support to NCZarr
Filter support has three goals:

1. Use the existing HDF5 filter implementations,
2. Allow filter metadata to be stored in the NumCodecs metadata format used by Zarr,
3. Allow filters to be used even when HDF5 is disabled

Detailed usage directions are define in docs/filters.md.

For now, the existing filter API is left in place. So filters
are defined using ''nc_def_var_filter'' using the HDF5 style
where the id and parameters are unsigned integers.

This is a big change since filters affect many parts of the code.

In the following, the terms "compressor" and "filter" and "codec" are generally
used synonomously.

### Filter-Related Changes:
* In order to support dynamic loading of shared filter libraries, a new library was added in the libncpoco directory; it helps to isolate dynamic loading across multiple platforms.
* Provide a json parsing library for use by plugins; this is created by merging libdispatch/ncjson.c with include/ncjson.h.
* Add a new _Codecs attribute to allow clients to see what codecs are being used; let ncdump -s print it out.
* Provide special headers to help support compilation of HDF5 filters when HDF5 is not enabled: netcdf_filter_hdf5_build.h and netcdf_filter_build.h.
* Add a number of new test to test the new nczarr filters.
* Let ncgen parse _Codecs attribute, although it is ignored.

### Plugin directory changes:
* Add support for the Blosc compressor; this is essential because it is the most common compressor used in Zarr datasets. This also necessitated adding a CMake FindBlosc.cmake file
* Add NCZarr support for the big-four filters provided by HDF5: shuffle, fletcher32, deflate (zlib), and szip
* Add a Codec defaulter (see docs/filters.md) for the big four filters.
* Make plugins work with windows by properly adding __declspec declaration.

### Misc. Non-Filter Changes
* Replace most uses of USE_NETCDF4 (deprecated) with USE_HDF5.
* Improve support for caching
* More fixes for path conversion code
* Fix misc. memory leaks
* Add new utility -- ncdump/ncpathcvt -- that does more or less the same thing as cygpath.
* Add a number of new test to test the non-filter fixes.
* Update the parsers
* Convert most instances of '#ifdef _MSC_VER' to '#ifdef _WIN32'
2021-09-02 17:04:26 -06:00
Edward Hartnett
ae3b083e20 turned off failing quantize test 2021-09-01 02:29:17 -06:00
Greg Sjaardema
f3041b3acf
Add a comment
Added comment indicating that we want integer division / truncation.
This should also trigger the tests to be run again; it looks like one of the tests just didn't run for some reason...
2021-08-16 10:06:45 -06:00
Greg Sjaardema
c3f20c88e9
Make variable easier to compress
Make the data in the variable `var1` easier to compress so that the compression tests will be more robust.  The zlib_ng library, for example, at level 1 does not compress a sequence of integers very well which resulted in the NetCDF-4 compressed file being larger than the uncompressed NetCDF-3 file.  With the change above, the variable contains `0,0,0,1,1,1,2,2,2,...,` which compresses at level 1 and the compression test is more robust.
2021-08-05 07:52:50 -06:00
Ward Fisher
9f798e2ed6 Merge branch 'virtual_datasets' of https://github.com/d70-t/netcdf-c into gh1983.wif 2021-07-19 09:44:35 -07:00
Dennis Heimbigner
d953899559 Move to Version 2 NCZarr Extended Meta-Data
re: https://github.com/zarr-developers/zarr-specs/issues/41

After discussions with the Zarr community, it was decided to
convert to a new representation of the NCZarr meta-data extensions: version 2.
These extensions store information necessary to mapping the Zarr data model
to the netcdf-4 data model.

The basic change is to remove the NCZarr specific objects: .nczarr, .nczgroup, .nczarray, and .nczattr.
The contents of these objects is moved into the corresponding existing Zarr objects as special keys. The mapping is as follows:

* ''.nczarr'' => ''/.zgroup/_NCZARR_SUPERBLOCK_''
* ''.nczgroup => ''.zgroup/_NCZARR_GROUP_''
* ''.nczarray => ''.zarray/_NCZARR_ARRAY_''
* ''.nczattr => ''.zattr/_NCZARR_ATTR_''

Backward compatibility is maintained by looking for the object ''/.nczarr''
and if found, then assuming that the dataset is in the older version 1 format.
This compatibility only supports reading of such version 1 datasets.

Documentation and test cases are also added.

Misc. Other Changes:
1. The json parsing code was added to the general library instead of nczarr only (ncjson.c, ncjson.h).
2. Improved support for different platform paths by allowing conversion
   to a single common path representation.
3. Add some new error codes.
4. Modify nccopy usage to mention the new chunking specification.
2021-07-17 16:55:30 -06:00
Ward Fisher
94262989eb
Merge pull request #1991 from gsjaardema/eliminate_need_for_hdf5-1.6-API
Remove need for HDF5-1.6 API being defined
2021-06-01 16:36:28 -06:00