how to expose a simple const char *array[]?

how to expose a simple const char *array[]?

[Roman Neuhauser]

hello,

i need a little help in exposing an array from zsh.

i'm trying to wrap the contents of Src/zshpaths.h in a module, initial
smoke tests look ok except this one thing: FPATH_SUBDIRS as an array.
the other modules that expose arrays use array_gsu structures as the
values need to be generated on the fly.  my case should be simpler so i
thought i'd get away without any fanfare, but it segfaults on access.

#define FPATH_SUBDIRS { "Calendar", "Chpwd", "Completion" /* , ... */ }

#ifdef FPATH_SUBDIRS
static const char *fpath_subdirs[] = FPATH_SUBDIRS;
#else
static const char *fpath_subdirs[] = { NULL };
#endif

static struct paramdef patab[] = {
    PARAMDEF("module_dir",      PM_SCALAR|PM_READONLY, &module_dir, NULL),
    PARAMDEF("sitescript_dir",  PM_SCALAR|PM_READONLY, &sitescript_dir, NULL),
    PARAMDEF("script_dir",      PM_SCALAR|PM_READONLY, &script_dir, NULL),
    PARAMDEF("sitefpath_dir",   PM_SCALAR|PM_READONLY, &sitefpath_dir, NULL),
    PARAMDEF("fixed_fpath_dir", PM_SCALAR|PM_READONLY, &fixed_fpath_dir, NULL),
    PARAMDEF("fpath_dir",       PM_SCALAR|PM_READONLY, &fpath_dir, NULL),
    PARAMDEF("fpath_subdirs",   PM_ARRAY |PM_READONLY, &fpath_subdirs, NULL)
};

it's surely doing something stupid...

-- 
roman

Re: how to expose a simple const char *array[]?

[Roman Neuhauser]

# neuhauser@sigpipe.cz / 2015-03-19 15:59:47 +0100:
> static const char *fpath_subdirs[] =
>     { "Calendar", "Chpwd", "Completion" /* , ... */ };
> 
> static struct paramdef patab[] = {
>     PARAMDEF("fpath_subdirs",   PM_ARRAY |PM_READONLY, &fpath_subdirs, NULL)
> };
> 
> it's surely doing something stupid...

it's surely *ME* doing something stupid...  and "stupid" as in
"trivially wrong": i'm just a dabbler in C.

-- 
roman

Re: how to expose a simple const char *array[]?

[Bart Schaefer]

On Mar 19,  3:59pm, Roman Neuhauser wrote:
}
} i'm trying to wrap the contents of Src/zshpaths.h in a module, initial
} smoke tests look ok except this one thing: FPATH_SUBDIRS as an array.
} the other modules that expose arrays use array_gsu structures as the
} values need to be generated on the fly.  my case should be simpler so i
} thought i'd get away without any fanfare, but it segfaults on access.

The only problem you have here is that FPATH_SUBDIRS is not terminated
with a final NULL element, but *fpath_subdirs[] must be so terminated
in order to be treated as an array parameter.

So your module will have to do something in its boot_() function to
copy from FPATH_SUBDIRS into an array one element longer, and poke a
NULL at the end.