Commit Graph

69 Commits

Author SHA1 Message Date
Dennis Heimbigner
231ae96c4b Add support for Zarr string type to NCZarr
* re: https://github.com/Unidata/netcdf-c/pull/2278
* re: https://github.com/Unidata/netcdf-c/issues/2485
* re: https://github.com/Unidata/netcdf-c/issues/2474

This PR subsumes PR https://github.com/Unidata/netcdf-c/pull/2278.
Actually is a bit an omnibus covering several issues.

## PR https://github.com/Unidata/netcdf-c/pull/2278
Add support for the Zarr string type.
Zarr strings are restricted currently to be of fixed size.
The primary issue to be addressed is to provide a way for user to
specify the size of the fixed length strings. This is handled by providing
the following new attributes special:
1. **_nczarr_default_maxstrlen** —
This is an attribute of the root group. It specifies the default
maximum string length for string types. If not specified, then
it has the value of 64 characters.
2. **_nczarr_maxstrlen** —
This is a per-variable attribute. It specifies the maximum
string length for the string type associated with the variable.
If not specified, then it is assigned the value of
**_nczarr_default_maxstrlen**.

This PR also requires some hacking to handle the existing netcdf-c NC_CHAR
type, which does not exist in zarr. The goal was to choose numpy types for
both the netcdf-c NC_STRING type and the netcdf-c NC_CHAR type such that
if a pure zarr implementation read them, it would still work and an
NC_CHAR type would be handled by zarr as a string of length 1.

For writing variables and NCZarr attributes, the type mapping is as follows:
* "|S1" for NC_CHAR.
* ">S1" for NC_STRING && MAXSTRLEN==1
* ">Sn" for NC_STRING && MAXSTRLEN==n

Note that it is a bit of a hack to use endianness, but it should be ok since for
string/char, the endianness has no meaning.

For reading attributes with pure zarr (i.e. with no nczarr
atribute types defined), they will always be interpreted as of
type NC_CHAR.

## Issue: https://github.com/Unidata/netcdf-c/issues/2474
This PR partly fixes this issue because it provided more
comprehensive support for Zarr attributes that are JSON valued expressions.
This PR still does not address the problem in that issue where the
_ARRAY_DIMENSION attribute is incorrectly set. Than can only be
fixed by the creator of the datasets.

## Issue: https://github.com/Unidata/netcdf-c/issues/2485
This PR also fixes the scalar failure shown in this issue.
It generally cleans up scalar handling.
It also adds a note to the documentation describing that
NCZarr supports scalars while Zarr does not and also how
scalar interoperability is achieved.

## Misc. Other Changes
1. Convert the nczarr special attributes and keys to be all lower case. So "_NCZARR_ATTR" now used "_nczarr_attr. Support back compatibility for the upper case names.
2. Cleanup my too-clever-by-half handling of scalars in libnczarr.
2022-08-27 20:21:13 -06:00
Ward Fisher
e3c43deba6 Address jump-misses-init issue. 2022-08-24 10:07:00 -06:00
Ward Fisher
2ccdf14697 Merge branch 'csz_bitround' of https://github.com/nco/netcdf-c into gh2232.wif 2022-04-01 10:43:34 -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
Charlie Zender
3299ba534b Add BitRound to ncgen 2022-02-19 16:08:36 -08:00
Charlie Zender
7b8c39f722 Change name to _QuantizeGranularBitRoundNumberOfSignificantDigits. Change identifier from QUANTIZEBR to QUANTIZEGBR to make room for new BitRound token = BR. 2022-02-19 15:55:36 -08:00
Dennis Heimbigner
89cc20a20d Rename GranularBitGroom to GranularBitRound
As per Charlie Zender's request (https://github.com/Unidata/netcdf-c/pull/2197#issuecomment-1022762863), the GranularBitGroom name is changed to GranularBitRound
with attendant code changes.
2022-01-28 13:04:16 -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
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
ca3dfe43b7 Fix FreeBSD fileno problem in the ncgen parsers 2021-09-28 14:03:19 -06:00
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
Dennis Heimbigner
ac421620b3 Fix the handling of certain alias types on CDL files.
re: https://github.com/Unidata/netcdf-c/issues/1977

PR https://github.com/Unidata/netcdf-c/pull/1753, changed ncgen
to allows certain type names to be used as identifiers in
selected situations.

An unwanted side effect was that existing type aliases no longer
were accepted by ncgen. Specifically, using the "long" type
caused an error.

I was able to figure out a better solution to the original
problem (https://github.com/Unidata/netcdf-c/issues/1750)
that also fixes this problem as well.

This PR fixes that problem in ncgen/ncgen.l,
and adds tests to ncdump/test_keywords.sh
2021-04-13 16:56:43 -06:00
Dennis Heimbigner
2afbdbd18f Add support for the XArray Zarr _ARRAY_DIMENSIONS attribute
The XArray implementation that uses Zarr for storage
provides a mechanism to simulate named dimensions.
It does this by adding a per-variable attribute called
_ARRAY_DIMENSIONS. This attribute contains a list of names
to be matched against the shape values of the variable.
In effect a named dimension is created with the name
_ARRAY_DIMENSIONS(i) and length shape(i) for all i
in range 0..rank(variable).
Both read and write support is provided.

This XArray support is only invoked if the mode value
of "xarray" is defined. So for example, as in this URL.
````
https://s3.us-west-1.amazonaws.com/bucket/dataset#mode=nczarr,xarray,s3
````
Note that the "xarray" mode flag also implies mode flag "zarr", so the above
is equivalent to this URL.
````
https://s3.us-west-1.amazonaws.com/bucket/dataset#mode=nczarr,zarr,xarray,s3
````

The primary change to implement this was to unify the handling
of dimension references in libnczarr/zsync.

A test for this and other pure-zarr features was added as
nczarr_test/run_purezarr.sh

Other changes:
* Make sure distcheck leaves no files around.
* Change the special attribute flag DIMSCALEFLAG to HIDDENATTRFLAG
  to support the xarray attribute.
* Annotate the zmap implementations with feature flags such as
  WRITEONCE (for zip files).
2021-02-24 13:46:11 -07:00
Ward Fisher
66a2cd371a More tweaking. 2020-12-07 14:45:14 -07:00
Ward Fisher
878866c039 Merge branch 'ncgenkw.dmh' of https://github.com/DennisHeimbigner/netcdf-c into gh1753.wif 2020-12-07 11:29:12 -07:00
Dennis Heimbigner
aeb3ac2809 Mostly revert the filter code to reduce its complexity of use.
re: https://github.com/Unidata/netcdf-c/issues/1836

Revert the internal filter code to simplify it. From the user's
point of view, the only visible changes should be:

1. The functions that convert text to filter specs have had their signature reverted and have been moved to netcdf_aux.h
2. Some filter API functions now return NC_ENOFILTER when inquiry is made about some filter.

Internally,the dispatch table has been modified to get rid of the filter_actions
entry and associated complex structures. It has been replaced with
inq_var_filter_ids and inq_var_filter_info entries and the dispatch table
version has been bumped to 3. Corresponding NOOP and NOTNC4 functions
were added to libdispatch/dnotnc4.c. Also, the filter_action entries
in dispatch tables were replaced for all dispatch code bases (HDF5, DAP2,
etc). This should only impact UDF users.

In the process, it became clear that the form of the filters
field in NC_VAR_INFO_T was format dependent, so I converted it to
be of type void* and pushed its management into the various dispatch
code bases. Specifically libhdf5 and libnczarr now manage the filters
field in their own way.

The auxilliary functions for parsing textual filter specifications
were moved to netcdf_aux.h and were renamed to the following:
* ncaux_h5filterspec_parse
* ncaux_h5filterspec_parselist
* ncaux_h5filterspec_free
* ncaux_h5filter_fix8

Misc. Other Changes:

1. Document NUG/filters.md updated to reflect the changes above.
2. All the old data types (structs and enums)
   used by filter_actions actions were deleted.
   The exception is the NC_H5_Filterspec because it is needed
   by ncaux_h5filterspec_parselist.
3. Clientside filters were removed -- another enhancement
   for which no-one ever asked.
4. The ability to remove filters was itself removed.
5. Some functionality needed by nczarr was moved from libhdf5
   to libsrc4 e.g. nc4_find_default_chunksizes
6. All the filterx code was removed
7. ncfilter.h and nc4filter.c no longer used

Misc. Unrelated Changes:

1. The nczarr_test makefile clean was leaving some directories; so
   add clean-local to take care of them.
2020-09-27 12:43:46 -06:00
Ward Fisher
a89e1f73b8 Merge branch 'ncgenchunks.dmh' of https://github.com/DennisHeimbigner/netcdf-c into master 2020-09-09 10:24:33 -06:00
Ward Fisher
31dee0c4da
Revert "Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries"" 2020-08-17 19:15:47 -06:00
Ward Fisher
16c27ca13f
Revert "Fix nczarr-experimental: improve build support, disengage hdf5 vs netcdf4 flags, and find AWS libraries" 2020-08-17 15:51:01 -06:00
Dennis Heimbigner
d538cf38c2 Fix nczarr-experimental to better support CMake and find AWS libraries
The primary fix is to improve CMake build support.
Specific changes include:
* CMake: Provide a better soln to locating the AWS SDK
  libraries; the new way is the preferred method as described in
  the aws-cpp-sdk documentation.
* CMake (and Automake): allow -DENABLE_S3_SDK (default off) to suppress
  looking for AWS libraries.
* CMake: add the complete set of nczarr tests
* CMake: add EXTERNL as needed to various .h files.
* Improve support for windows drive letters in paths.
* Add nczarr and s3 flags to nc-config
* For VisualStudio X nczarr, cleanup the NAN+INFINITY handling
* Convert _MSC_VER -> _WIN32 and vice versa as needed
* NCZarr - support multiple platform paths including windows, cygwin.
  mingw, etc.
* NCZarr - sort the test outputs because different platforms
  produce directory contents in different orders.

One big change concerns netcdf-c/CMakeLists.txt and netcdf-c/configure.ac.
In the current versions, it was the case that --disable-hdf5
disabled netcdf-4 (libsrc4). With nczarr, this can no longer
be the case because nczarr requires libsrc4 even if libhdf5
is disabled. So, I modified the above files to move the
format options (HDF5, NCZarr, HDF4, etc) to a single place
near the front of the files. Now it is the case that:
* Enabling any of the formats that require libsrc4
  also does an implicit --enable-netcdf4.
* --disable-netcdf4 | --disable-netcdf-4 now becomes
  and alias for --disable-hdf5.

There are probably some bugs in this change in terms of
dependencies between format options.

Problems:
* CMake S3 support is still not working for Visual Studio
* A recent issue points out that there is work to do on handling
  UTF8 filenames, but that will be addressed in a separate fix.

Notes:
* Consider converting all of our includes/.h files to use EXTERNL
2020-07-12 12:21:56 -06:00
Dennis Heimbigner
90b912b7e8 Allow use of type keywords as identifier in formats that do not support that type.
Built-in type-name keywords are currently flagged when used as
identifiers in formats that do not support that type.  So if a
user declares a dimension named "string" in a classic .cdl file,
it causes an error.

This PR modifies ncgen to allow those format-specific type keywords
to be used as identifiers when compiling to formats that do not
support that type. Also added a test for this.

Also a couple of misc. changes to conditionalize some debug output.
2020-06-05 17:03:29 -06:00
Dennis Heimbigner
68a98f6e81 Fix ncgen handling of big data sections
The current ncgen does not properly handle very large
data sections. Apparently this is very uncommon because
it was only discovered in testing the new zarr code.

The fix required a new approach to processing data sections.
Unfortunately, the resulting ncgen is slower than before
but at least it is, I think, now correct.

The added test cases are in libnczarr, and so will
not show up until that is incorporated into master.

Note also that fortran code generation changed, but
has not been tested here.

Misc. Changes
1. Cleanup error handling in ncgen -lc and -lb output
2. Cleanup Makefiles for ncgen to remove unused code
3. Added a program, ncgen/ncdumpchunks, to print
   the data for a .nc file on a per-chunk format.
4. Made the XGetOpt change in PR https://github.com/Unidata/netcdf-c/pull/1694
   for ncdump/ncvalidator
2020-05-14 11:20:46 -06:00
Dennis Heimbigner
44d0dcaad2 Add support for multiple filters per variable.
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.
2020-02-16 12:59:33 -07:00
Dennis Heimbigner
98caf87116 Fix ncgen handling of octal constants (with leading 0).
re: https://github.com/Unidata/netcdf-c/issues/1330

The ncgen utility is documented to accept octal integer constants
if the leading digit is zero. This was not implemented. Fix ncgen.l
to properly handle such constants. Also add a test to c0.cdl.
2019-02-25 20:57:23 -07:00
Dennis Heimbigner
8714066b18 Fix errors when building on big-endian machine
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
2019-01-31 21:13:06 -07:00
Ward Fisher
c21820a1ae Merge branch 'master' into ansifix.dmh 2019-01-02 22:26:59 -08:00
Ward Fisher
c62d7eb541 Merge remote-tracking branch 'origin/gh1233.dmh' into pr-aggregation.wif 2018-12-30 23:55:30 -08:00
Dennis Heimbigner
735ae80928 merge master and fix conflicts 2018-12-12 11:47:54 -07:00
Ward Fisher
7fd7696940 ncgen directory updated 2018-12-06 15:40:43 -07:00
Dennis Heimbigner
1a7531392f Make the netcdf-c library compile with gcc -ansi.
Primary fixes to get -ansi to work.
1. Convert all '//' C++ style comments to /*...*/ or to use #if 0...#endif
2. It turns out that when -ansi is specified, then a number of
   functions no longer are defined in the header -- but they are still
   in the .so file.<br>
   The big example is strdup(). So, added code to include/ncconfig.h to define
   externs for those missing functions that occur in more than one place.
   These are enabled if !_WIN32 && __STDC__ == 1 (__STDC__ is supposed to
   be the equivalent compile time flag to -ansi). Note that this requires
   config.h (which references ncconfig.h) to be included in files where it is
   currently not included. Single uses will be only in the file that uses them.
3. Added mmap test for the MAP_ANONYMOUS flag to configure.ac. Apparently
   this is not always defined with -ansi.
4. fix some large integer constants in nc_test4/tst_atts3.c and nc_test4/tst_filterparser.c
   to avoid compiler complaints.
5. fix a double constant in nc_test4/tst_filterparser.c to avoid compiler complaints.

[Note I suspect #4 and #5 will be a problem on big-endian machines, but we have no way to test]

Misc. Changes:
1. convert more instances of _MSC_VER to _WIN32.
2. added some debugging code to include/nctestserver.h
3. added comment about libdispatch/drc.c always being compiled.
4. modify parser generation in ncgen to remove unneeded files.
2018-12-05 19:20:43 -07:00
Dennis Heimbigner
30d63bbaa5 Fix failings of nc_test/run_inmemory.sh
re: issue https://github.com/Unidata/netcdf-c/issues/1233

Changes:

1. remove exit that was there for testing.
2. the program tst_open_mem must be netcdf-4 only.
3. fix some diff problems
   - Change dataset name for tst_inmemory4_create to tst_inmemory4
   - Modify tst_inmemory.c to reorder the variables (somewhat major rewrite)

Minor Unrelated Fixes:
1. fix comment problem in nc_provenance.h
2. Fix memory leak in tst_open_mem.c
3. fix ncdump/bindata.c to properly compile if netcdf4 is disabled.
4. minor changes to ncgen.l
2018-12-04 19:22:02 -07:00
Dennis Heimbigner
b89e3f50d0 Fix introduced alert https://lgtm.com/projects/g/Unidata/netcdf-c/rev/pr-5fdf9cb537c1a981abb3838fdfb061b1088636f0
by removing offending, unused global variable.
2018-11-15 10:31:36 -07:00
Dennis Heimbigner
751300ec59 Fix more memory leaks in netcdf-c library
This is a follow up to PR https://github.com/Unidata/netcdf-c/pull/1173

Sorry that it is so big, but leak suppression can be complex.

This PR fixes all remaining memory leaks -- as determined by
-fsanitize=address, and with the exceptions noted below.

Unfortunately. there remains a significant leak that I cannot
solve. It involves vlens, and it is unclear if the leak is
occurring in the netcdf-c library or the HDF5 library.

I have added a check_PROGRAM to the ncdump directory to show the
problem.  The program is called tst_vlen_demo.c To exercise it,
build the netcdf library with -fsanitize=address enabled. Then
go into ncdump and do a "make clean check".  This should build
tst_vlen_demo without actually executing it.  Then do the
command "./tst_vlen_demo" to see the output of the memory
checker.  Note the the lost malloc is deep in the HDF5 library
(in H5Tvlen.c).

I am temporarily working around this error in the following way.
1. I modified several test scripts to not execute known vlen tests
   that fail as described above.
2. Added an environment variable called NC_VLEN_NOTEST.
   If set, then those specific tests are suppressed.

This should mean that the --disable-utilities option to
./configure should not need to be set to get a memory leak clean
build.  This should allow for detection of any new leaks.

Note: I used an environment variable rather than a ./configure
option to control the vlen tests. This is because it is
temporary (I hope) and because it is a bit tricky for shell
scripts to access ./configure options.

Finally, as before, this only been tested with netcdf-4 and hdf5 support.
2018-11-15 10:00:38 -07:00
Ed Hartnett
b03277caea
Merge branch 'master' into ejh_streq 2018-05-17 04:26:59 -06:00
Ed Hartnett
0c0d066927 changed macro STREQ to NCSTREQ to avoid name collusion with HDF4 library 2018-05-12 08:55:51 -06:00
Ward Fisher
0f36b279be Merge remote-tracking branch 'origin/cleanncgen.dmh' into pr-aggregate.wif 2018-04-20 13:06:26 -06:00
Dennis Heimbigner
99fccab359 1. Keep up to date by merging master
2. Fixed plugin building (nc_test4/hdf5plugins)
   to be done properly by cmake and automake.
4. Duplicated part of the nc_test4 filter test code
   in examples/C

An incomplete and untested set of hooks exist
for OS-X in nc_test4/findplugins.in. They need testing.
2018-01-16 11:00:09 -07:00
Ward Fisher
efff646587 Quick test of something to resolve conflict in generated files. 2017-11-13 12:33:19 -07:00
Ward Fisher
16d6f94f30 Merge branch 'master' into filters.dmh 2017-11-13 11:15:02 -07:00
Dennis Heimbigner
4ee89ed71b Fix conflicts with master 2017-11-06 13:15:10 -07:00
Dennis Heimbigner
026544964a Cleanup some ncgen memory problems 2017-10-31 14:03:57 -06:00
Dennis Heimbigner
815f4e4a18 Cleanup ncgen memory management 2017-10-30 15:52:08 -06:00
Dennis Heimbigner
9983b9d911 re e-support UBS-599337
re pull request https://github.com/Unidata/netcdf-c/pull/405
re pull request https://github.com/Unidata/netcdf-c/pull/446

Notes:
1. This branch is a cleanup of the magic.dmh branch.
2. magic.dmh was originally merged, but caused problems with parallel IO.
   It was re-issued as pull request https://github.com/Unidata/netcdf-c/pull/446.
3. This branch + pull request replace any previous pull requests and magic.dmh branch.

Given an otherwise valid netCDF file that has a corrupted header,
the netcdf library currently crashes. Instead, it should return
NC_ENOTNC.

Additionally, the NC_check_file_type code does not do the
forward search required by hdf5 files. It currently only looks
at file position 0 instead of 512, 1024, 2048,... Also, it turns
out that the HDF4 magic number is assumed to always be at the
beginning of the file (unlike HDF5).
The change is localized to libdispatch/dfile.c See
https://support.hdfgroup.org/release4/doc/DSpec_html/DS.pdf

Also, it turns out that the code in NC_check_file_type is duplicated
(mostly) in the function libsrc4/nc4file.c#nc_check_for_hdf.

This branch does the following.
1. Make NC_check_file_type return NC_ENOTNC instead of crashing.
2. Remove nc_check_for_hdf and centralize all file format checking
   NC_check_file_type.
3. Add proper forward search for HDF5 files (but not HDF4 files)
   to look for the magic number at offsets of 0, 512, 1024...
4. Add test tst_hdf5_offset.sh. This tests that hdf5 files with
   an offset are properly recognized. It does so by prefixing
   a legal file with some number of zero bytes: 512, 1024, etc.
5. Off-topic: Added -N flag to ncdump to force a specific output dataset name.
2017-10-24 16:25:09 -06:00
Ward Fisher
399a43ae89 Updated nc_test to respect USE_CDF5 2017-09-18 13:24:11 -06:00
Dennis Heimbigner
ddacf2db38 When ncgen is invoked without a -k flag,
it tries to infer the file kind based on
the constructs and types used in the .cdl
file. Previously, it included cdf5 as an
inferrable kind, but this is almost never
what is wanted. So limit inferable kinds
to netcdf classic vs netcdf enhanced.
Also fix tst_inttags4.sh test.
2017-09-15 21:03:05 -06:00
Ward Fisher
08c51e6064 Corrected a couple issues uncovered when revisiting https://github.com/Unidata/netcdf-c/issues/244 2017-06-14 14:01:09 -06:00
Dennis Heimbigner
d37ac215e2 Add new capabilities to filter code:
1. Allow nccopy to apply filters, especially on the output file.
   This provides a third way to do this other than using ncgen or
   programatically
2. Make sure that even if the filter code is not available, it is
   possible to see the filter id and parameters for variables using
   e.g ncdump -hs.
3. Fix bug in nccopy so that the input file does
   not necessarily have to be netcdf-4.
4. At last minute decided to change to using a
   single "_Filter" attribute for ncgen
5. Added a test to tst_filter.sh to generate C code using ncgen.
2017-05-14 18:10:02 -06:00
Dennis Heimbigner
7c3164577e Finalize the compression support.
This relies on the HDF5 capability to
dynamically load compression filters.
Note that a compression filter is just
a subcase of filters.

The primary user-visible changes are as follows:
1. Add a standard header "netcdf_filter.h" that defines
   the necessary API extensions
2. Modify ncgen to support two new special attributes
   "_Filter_ID" and "_Filter_Parameters" so that compression
   can be turned on when creating a file using ncgen.
4. Add a detailed description of filtering support
   to the user's guide; see the file filters.md
5. Add a test case directory for this: nc_test4/filter_test.
   It is fragile and a ./configure flags (-enable-filter-test)
   is defined (default disabled) to shut this off this test
   to avoid spurious 'make check' failures.

Note that the HDF5 documentation is not up-to-date, so
much of what is encoded here comes from examining the
actual code in the file H5PL.c in the HDF5 source code.
2017-04-27 13:01:59 -06:00
Ward Fisher
156e6a8e39 Merged master into ghpull-375 2017-03-27 15:31:34 -06:00
Dennis Heimbigner
38bf48d2ca re: gihub issue https://github.com/Unidata/netcdf-c/issues/380
Re: esupport ticket support-netcdf : SKS-534087
Ncgen treats an integer with just a U/u suffix as uint64 instead of uint32.
Fix is in ncgen.l
2017-03-24 18:56:14 -06:00