The file docs/indexing.dox tries to provide design
information for the refactoring.
The primary change is to replace all walking of linked
lists with the use of the NCindex data structure.
Ncindex is a combination of a hash table (for name-based
lookup) and a vector (for walking the elements in the index).
Additionally, global vectors are added to NC_HDF5_FILE_INFO_T
to support direct mapping of an e.g. dimid to the NC_DIM_INFO_T
object. These global vectors exist for dimensions, types, and groups
because they have globally unique id numbers.
WARNING:
1. since libsrc4 and libsrchdf4 share code, there are also
changes in libsrchdf4.
2. Any outstanding pull requests that change libsrc4 or libhdf4
are likely to cause conflicts with this code.
3. The original reason for doing this was for performance improvements,
but as noted elsewhere, this may not be significant because
the meta-data read performance apparently is being dominated
by the hdf5 library because we do bulk meta-data reading rather
than lazy reading.
Modified provenance code to allocate the minimal space
needed for _NCProperties attribute in file. Basically
required using malloc in the provenance code and in ncdump.
Otherwise should cause no externally visible effects.
Also removed the ENABLE_FILEINFO from configure.ac since
the provenance code is no longer optional.
re: github netcdf-c issue #271
This occurs for several reasons, including:
1. using H5Aopen_name instead of H5Aexists to test if attribute exists.
2. using H5Eset_auto instead of H5Eset_auto2.
There are probably others that will have to be extinguished as encountered.
p.s Hope I did not overdo this and kill too much.
Charlie Zender noted that we forgot to define what happens for
various netcdf API attribute operations, notably nc_inq_att()
and nc_get_att().
So, I added a list of legal and illegal api calls for the provenance
attributes in docs/attribute_conventions.md.
I also added more test cases to ncdump/tst_fileinfo.c to verify
and fixed resultant errors.
This consists of a persistent attribute named
_NCProperties plus two computed attributes
_IsNetcdf4 and _SuperblockVersion.
See the 'Provenance Attributes' section
of docs/attribute_conventions.md for details.
error occurs after an "exit:" label.
Corrected a dozen Coverity errors (mainly allocation issues, along with a few
other things):
711711, 711802, 711803, 711905, 970825, 996123, 996124, 1025787,
1047274, 1130013, 1130014, 1139538
Refactored internal fill-value code to correctly handle string types, and
especially to allow NULL pointers and null strings (ie. "") to be
distinguished. The code now avoids partially aliasing the two together
(which only happened on the 'write' side of things and wasn't reflected on
the 'read' side, adding to the previous confusion).
Probably still weak on handling fill-values of variable-length and compound
datatypes.
Refactored the recursive metadata reads a bit more, to process HDF5 named
datatypes and datasets immediately, avoiding chewing up memory for those
types of objects, etc.
Finished uncommenting and updating the nc_test4/tst_fills2.c code (as I'm
proceeding alphabetically through the nc_test4 code files).
to clean up resources properly on failure.
Refactored doubly-linked list code for objects in the libsrc4 directory,
cleaning up the add/del routines, breaking out the common next/prev
pointers into a struct and extracting the add/del operations on them,
changed the list of dims to add new dims in the same order as the other
types, made all add routines able to optionally return a pointer to the
newly created object.
Removed some dead code (pg_var(), nc4_pg_var1(), nc4_pg_varm(), misc. small
routines, etc)
Fixed fill value handling for string types in nc4_get_vara().
Changed many malloc()+strcpy() pairs into calls to strdup().
Cleaned up misc. other minor Coverity issues.
Also added ability capability for netCDF-4 to write and read NIL
values for string type attributes and variables, so these can be read
if used in HDF5 files.
Include are additions to CMakeLists files to reflect new tests.
contain as little file-type specific info as possible. It
modifies especially libsrc so that all of the netcdf-3 data
that used to be in struct NC is now kept in a separate chunk
of data pointed to by the struct NC. This makes all of
current protocols consistent: netcdf-3, netcdf-4, and dap.
reported by static analysis, including memory leak in ncdump, missing
size_t cast for chunk cache. Fixed various doc problems, including
byte vs. char issues, missing NC_UBYTE in type list, needed link to
"Building with Windows" page.
