cqp_get_registry(): Initialization of CQP required

[ablaette]

Trying to implement a function in the cwbtools package that performs a testload for a corpus,
I realized some really odd behavior of the cqp_get_registry() function.

The cqp_get_registry() works as expected, if cqp_initialize() has been
called before tbe first call of cqp_get_registry(). Given the two
alternative registry directories used in the following example exist,
the following code works.

library(RcppCWB)
cqp_initialize()
cqp_reset_registry(path.expand("~/cwb2/registry"))
cqp_get_registry()

Sys.setenv(CORPUS_REGISTRY = path.expand("~/Data/cwb/registry"))
cqp_get_registry()

But if cqp_get_registry() is called before cqp_initialize(),
cqp_get_registry() will grab strings from memory in an unexpected and
definitely unintended manner.

library(RcppCWB)
cqp_get_registry() # Problems when called before cqp_initialize
cqp_initialize()
cqp_get_registry()

Looking at the C code of the cl_standard_registry() C function that is
the worker behind the R function cqp_get_registry(), I find it hard
(impossible at this stage) to understand what happens.

cl_standard_registry()
{
  if (regdir == NULL)
    regdir = getenv(REGISTRY_ENVVAR);
  if (regdir == NULL)
    regdir = REGISTRY_DEFAULT_PATH;
  return regdir;
}

A workaround might be to call cqp_initialize() by default upon loading
RcppCWB. But that would be a workaround and I am deeply dissatisfied with, as I do not
yet understand the odd behavior reported.

[ablaette]

A new implementation of cqp_get_registry() does not reference the regdir variable which may have been overwritten, but the registry variable. I think this solved the issue.