re: https://github.com/Unidata/netcdf-c/issues/1827
The issue is partly resolved by this PR. The proximate problem appears to be that the semantics of mkstemp in **nix is different than the semantics of _mktemp_s in Windows. I had thought they were the same but that is incorrect. The _mktemp_s function will only produce 26 different files and so the netcdf temp file code will fail after about that many iterations.
So, to solve this, I created my own version of mkstemp for windows that uses a random number generator. This appears to solve the reported issue. I also added the testcase ncdap_test/test_manyurls but made it conditional on --enable-dap-long-tests because it is very slow.
I did note that the provided test program now fails after some 800 iterations with a libcurl error claiming it cannot resolve the host name. My belief is that the library is just running out of resources at this point: too many open curl handles or some such. I doubt if this failure is fixable.
So bottom line is that it is really important to do nc_close when you are finished with a file.
Misc. Other Changes:
1. I took the opportunity to clean up some bad string hacks in the code. Specifically
* change all uses of strncat to strlcat
* remove old string hacks: occoncat and occopycat
2. Add heck to see if test.opendap.org is running and if not, then skip test
3. Make CYGWIN use TEMP environment variable
re: https://github.com/Unidata/netcdf-c/issues/1876
and: https://github.com/Unidata/netcdf-c/pull/1835
and: https://github.com/Unidata/netcdf4-python/issues/1041
The change in PR 1835 was correct with respect to using %20 instead of '+'
for encoding blanks. However, it was a mistake to assume everything was
unencoded and then to do encoding ourselves. The problem is that
different servers do different things, with Columbia being an outlier.
So, I have added a set of client controls that can at least give
the caller some control over this. The caller can append
the following fragment to his URL to control what gets encoded before
sending it to the server. The syntax is as follows:
````
https://<host>/<path>/<query>#encode=path|query|all|none
````
The possible values:
* path -- URL encode (i.e. %xx encode) as needed in the path part of the URL.
* query -- URL encode as needed in the query part of the URL.
* all -- equivalent to ````#encode=path,query````.
* none -- do not url encode any part of the URL sent to the server; not strictly necessary, so mostly for completeness.
Note that if "encode=" is used, then before it is processed, all encoding
is turned of so that ````#encode=path```` will only encode the path
and not the query.
The default is ````#encode=query````, so the path is left untouched,
but the query is always encoded.
Internally, this required changes to pass the encode flags down into
the OC2 library.
Misc. Unrelated Changes:
* Shut up those irritating warning from putget.m4
cloud using a variant of the Zarr protocol and storage
format. This enhancement is generically referred to as "NCZarr".
The data model supported by NCZarr is netcdf-4 minus the user-defined
types and the String type. In this sense it is similar to the CDF-5
data model.
More detailed information about enabling and using NCZarr is
described in the document NUG/nczarr.md and in a
[Unidata Developer's blog entry](https://www.unidata.ucar.edu/blogs/developer/en/entry/overview-of-zarr-support-in).
WARNING: this code has had limited testing, so do use this version
for production work. Also, performance improvements are ongoing.
Note especially the following platform matrix of successful tests:
Platform | Build System | S3 support
------------------------------------
Linux+gcc | Automake | yes
Linux+gcc | CMake | yes
Visual Studio | CMake | no
Additionally, and as a consequence of the addition of NCZarr,
major changes have been made to the Filter API. NOTE: NCZarr
does not yet support filters, but these changes are enablers for
that support in the future. Note that it is possible
(probable?) that there will be some accidental reversions if the
changes here did not correctly mimic the existing filter testing.
In any case, previously filter ids and parameters were of type
unsigned int. In order to support the more general zarr filter
model, this was all converted to char*. The old HDF5-specific,
unsigned int operations are still supported but they are
wrappers around the new, char* based nc_filterx_XXX functions.
This entailed at least the following changes:
1. Added the files libdispatch/dfilterx.c and include/ncfilter.h
2. Some filterx utilities have been moved to libdispatch/daux.c
3. A new entry, "filter_actions" was added to the NCDispatch table
and the version bumped.
4. An overly complex set of structs was created to support funnelling
all of the filterx operations thru a single dispatch
"filter_actions" entry.
5. Move common code to from libhdf5 to libsrc4 so that it is accessible
to nczarr.
Changes directly related to Zarr:
1. Modified CMakeList.txt and configure.ac to support both C and C++
-- this is in support of S3 support via the awd-sdk libraries.
2. Define a size64_t type to support nczarr.
3. More reworking of libdispatch/dinfermodel.c to
support zarr and to regularize the structure of the fragments
section of a URL.
Changes not directly related to Zarr:
1. Make client-side filter registration be conditional, with default off.
2. Hack include/nc4internal.h to make some flags added by Ed be unique:
e.g. NC_CREAT, NC_INDEF, etc.
3. cleanup include/nchttp.h and libdispatch/dhttp.c.
4. Misc. changes to support compiling under Visual Studio including:
* Better testing under windows for dirent.h and opendir and closedir.
5. Misc. changes to the oc2 code to support various libcurl CURLOPT flags
and to centralize error reporting.
6. By default, suppress the vlen tests that have unfixed memory leaks; add option to enable them.
7. Make part of the nc_test/test_byterange.sh test be contingent on remotetest.unidata.ucar.edu being accessible.
Changes Left TO-DO:
1. fix provenance code, it is too HDF5 specific.
Primary change is to cleanup code and remove duplicated code.
1. Unify the rc file reading into libdispatch/drc.c. Eventually extend
if we need rc file for netcdf itself as opposed to the dap code.
2. Unify the extraction from the rc file of DAP authorization info.
3. Misc. other small unifications: make temp file, read file.
4. Avoid use of libcurl when reading file:// because
there is some kind of problem with the Visual Studio version.
Might be related to the winpath problem.
In any case, do direct read instead.
5. Add new error code NC_ERCFILE for errors in reading RC file.
6. Complete documentation cleanup as indicated in this comment
https://github.com/Unidata/netcdf-c/pull/472#issuecomment-325926426
7. Convert some occurrences of #ifdef _WIN32 to #ifdef _MSC_VER
were added to provide a path name converter from e.g. cygwin
paths to e.g. windows paths. This is necessary because
the shell scripts may produce cygwin paths, but the code
may have been compiled with Visual Studio. Similar issues
arise with Mingw.
At appropriate places, and if using Visual Studio or Mingw,
I added calls to the path conversion code.
Apparently I forgot to find all the places where this
conversion was needed. So this pr does the following:
1. Push the calls to the converter to the various libXXX
directories and out of libdispatch/dfile.c.
2. Add conversion calls to other parts of the code like oc2.
I also turns out that conversion code in dapcvt.c
had a bug when handling DAP Byte type under visual studio.
Notes:
1. there may still be places I missed that need to do path conversion.
2. need to make sure that calls to e.g. H5open also use converted path.
Specific changes:
1. Add dap4 code: libdap4 and dap4_test.
Note that until the d4ts server problem is solved, dap4 is turned off.
2. Modify various files to support dap4 flags:
configure.ac, Makefile.am, CMakeLists.txt, etc.
3. Add nc_test/test_common.sh. This centralizes
the handling of the locations of various
things in the build tree: e.g. where is
ncgen.exe located. See nc_test/test_common.sh
for details.
4. Modify .sh files to use test_common.sh
5. Obsolete separate oc2 by moving it to be part of
netcdf-c. This means replacing code with netcdf-c
equivalents.
5. Add --with-testserver to configure.ac to allow
override of the servers to be used for --enable-dap-remote-tests.
6. There were multiple versions of nctypealignment code. Try to
centralize in libdispatch/doffset.c and include/ncoffsets.h
7. Add a unit test for the ncuri code because of its complexity.
8. Move the findserver code out of libdispatch and into
a separate, self contained program in ncdap_test and dap4_test.
9. Move the dispatch header files (nc{3,4}dispatch.h) to
.../include because they are now shared by modules.
10. Revamp the handling of TOPSRCDIR and TOPBUILDDIR for shell scripts.
11. Make use of MREMAP if available
12. Misc. minor changes e.g.
- #include <config.h> -> #include "config.h"
- Add some no-install headers to /include
- extern -> EXTERNL and vice versa as needed
- misc header cleanup
- clean up checking for misc. unix vs microsoft functions
13. Change copyright decls in some files to point to LICENSE file.
14. Add notes to RELEASENOTES.md
This supports better authorization
handling for DAP requests, especially redirection
based authorization. I also added a new test case
ncdap_tests/testauth.sh.
Specifically, suppose I have a netrc file /tmp/netrc
containing this.
machine uat.urs.earthdata.nasa.gov login xxxxxx password yyyyyy
Also suppose I have a .ocrc file containing these lines
HTTP.COOKIEJAR=/tmp/cookies
HTTP.NETRC=/tmp/netrc
Assume that .ocrc is in the local directory or HOME.
Then this command should work (assuming a valid login and password).
ncdump -h "https://54.86.135.31/opendap/data/nc/fnoc1.nc"
should be under ENABLE_DAP_REMOTE_TESTS.
Fixed to make sure that this is so.
Also attempted to fix ncdap_test/CMakeLists.txt,
but probably got it wrong.
HT to Nico Schlomer.
2. Attempted to reduce the number of conversion errors
when -Wconversion is set. Fixed oc2, but
rest of netcdf remains to be done.
HT to Nico Schlomer.
3. When doing #2, I discovered an error in ncgen.y
that has remained hidden. This required some other
test case fixes.
Some servers do not properly
implement the current DAP2 spec.
It turns out that this server is one of those:
http://nomads.ncep.noaa.gov:9090/
When a reference such as this is made:
http://nomads.ncep.noaa.gov:9090/dods/gens/gens20140123/gep_all_12z?prmslmsl[0][0][0][0:359]
tt is returning this:
Dataset {
float prmslmsl[ens=1][time=1][lat=1][lon=360];
} gens%2fgens20140123%2fgep_all_12z;
when it should be returning this:
Dataset {
Structure {
float prmslmsl[ens=1][time=1][lat=1][lon=360];
} prmslmsl;
} gens%2fgens20140123%2fgep_all_12z;
The reason is that when picking fields out of a grid,
one must maintain the fully qualified name, so the grid
is converted to an enclosing structure.
It turns out that the problem was that
when I create the new structure node, I was
improperly linking it into the existing graph.
This caused a null pointer failure.
Fix is to make sure the relevant field (node->root)
is set.
