Commit Graph

4 Commits

Author SHA1 Message Date
Ward Fisher
3a0d55f137 Removed a null assignment. 2018-05-31 16:40:11 -06:00
Dennis Heimbigner
4b936ee26a Fix use of 'int' to represent 'hid_t' that caused HDF5 1.10 to fail.
re: github issue https://github.com/Unidata/netcdf-fortran/issues/82

This was originally discovered in the Fortran tests, but is
a problem in the C library.

The problem only occurred when using HDF5-1.10.x.  The reason it
failed is that starting with 1.10, the hid_t type was changed
from 32 bits to 64 bits.
The function libsrc4/nc4memcb.c#NC4_image_init was using type int (doh!)
to return the hdf fileid instead of hid_t type.  This, of course,
caused the id to be truncated and in turn later use of the id
caused hdf5 to fail.

Fix is trivial: replace int with hid_t. This also requires a related
change in nc4mem.c.

Also added the test case derived from the original Fortran code.

You would think I would learn...
2018-05-30 14:47:37 -06:00
Dennis Heimbigner
5bc174920f re: esupport MQO-415619
There is an error in handling the nc_create_memio function
as noted in the above esupport thread.
This attempts to fix it.

Also do a master merge
2018-05-03 21:02:32 -06:00
Dennis Heimbigner
ccc70d640b re: esupport MQO-415619
and https://github.com/Unidata/netcdf-c/issues/708

Expand the NC_INMEMORY capabilities to support writing and accessing
the final modified memory.

Three new functions have been added:
nc_open_memio, nc_create_mem, and nc_close_memio.

The following new capabilities were added.
1. nc_open_memio() allows the NC_WRITE mode flag
   so a chunk of memory can be passed in and be modified
2. nc_create_mem() allows the NC_INMEMORY flag to be set
   to cause the created file to be kept in memory.
3. nc_close_mem() allows the final in-memory contents to be
   retrieved at the time the file is closed.
4. A special flag, NC_MEMIO_LOCK, is provided to ensure that
   the provided memory will not be freed or reallocated.

Note the following.
1. If nc_open_memio() is called with NC_WRITE, and NC_MEMIO_LOCK is not set,
   then the netcdf-c library will take control of the incoming memory.
   This means that the original memory block should not be freed
   but the block returned by nc_close_mem() must be freed.
2. If nc_open_memio() is called with NC_WRITE, and NC_MEMIO_LOCK is set,
   then modifications to the original memory may fail if the space available
   is insufficient.

Documentation is provided in the file docs/inmemory.md.
A test case is provided: nc_test/tst_inmemory.c driven by
nc_test/run_inmemory.sh

WARNING: changes were made to the dispatch table for
the close entry. From int (*close)(int) to int (*close)(int,void*).
2018-02-25 21:45:31 -07:00