hll.c

/*
Copyright (C) 2005-2009, Parrot Foundation.
$Id$

=head1 NAME

src/hll.c - High Level Language support

=head1 DESCRIPTION

The Parrot core sometimes has to create new PMCs which should map to the
current HLL's defaults. The current language and a typemap provides this
feature.

=head1 DATA

   interp->HLL_info

   @HLL_info = [
     [ hll_name, hll_lib, { core_type => HLL_type, ... }, namespace, hll_id ],
     ...
     ]

=head2 Functions

=over 4

=cut

*/

#include "parrot/parrot.h"
#include "parrot/dynext.h"
#include "hll.str"

/* HEADERIZER HFILE: include/parrot/hll.h */

/* HEADERIZER BEGIN: static */
/* Don't modify between HEADERIZER BEGIN / HEADERIZER END.  Your changes will be lost. */

PARROT_CANNOT_RETURN_NULL
PARROT_WARN_UNUSED_RESULT
static PMC* new_hll_entry(PARROT_INTERP, ARGIN_NULLOK(STRING *entry_name))
        __attribute__nonnull__(1);

#define ASSERT_ARGS_new_hll_entry __attribute__unused__ int _ASSERT_ARGS_CHECK = \
       PARROT_ASSERT_ARG(interp)
/* Don't modify between HEADERIZER BEGIN / HEADERIZER END.  Your changes will be lost. */
/* HEADERIZER END: static */

/* for shared HLL data, do COW stuff */
#define START_READ_HLL_INFO(interp, hll_info)
#define END_READ_HLL_INFO(interp, hll_info)
#define START_WRITE_HLL_INFO(interp, hll_info) \
    do { \
        if (PMC_sync((interp)->HLL_info)) { \
            (hll_info) = (interp)->HLL_info = \
                Parrot_clone((interp), (interp)->HLL_info); \
            if (PMC_sync((interp)->HLL_info)) \
                mem_internal_free(PMC_sync((interp)->HLL_info)); \
        } \
    } while (0)
#define END_WRITE_HLL_INFO(interp, hll_info)


/*

=item C<static PMC* new_hll_entry(PARROT_INTERP, STRING *entry_name)>

Create a new HLL information table entry.
Takes an interpreter name and (optional) entry name.
Returns a pointer to the new entry.
Used by Parrot_register_HLL and Parrot_register_HLL_lib.

=cut

*/

PARROT_CANNOT_RETURN_NULL
PARROT_WARN_UNUSED_RESULT
static PMC*
new_hll_entry(PARROT_INTERP, ARGIN_NULLOK(STRING *entry_name))
{
    ASSERT_ARGS(new_hll_entry)
    PMC * const hll_info = interp->HLL_info;
    const INTVAL id      = VTABLE_elements(interp, hll_info);

    PMC *entry_id;

    /*
     * ATT: all items that are owned by the HLL_info structure
     *      have to be created as constant objects, because
     *      this structure isn't marked by GC
     */
    PMC * const entry = constant_pmc_new(interp, enum_class_FixedPMCArray);

    if (entry_name && !STRING_IS_EMPTY(entry_name)) {
        char   * const cstring    = Parrot_str_to_cstring(interp, entry_name);
        const  UINTVAL len        = Parrot_str_byte_length(interp, entry_name);
        STRING *const_name        = Parrot_str_new_init(interp, cstring,
            len, PARROT_DEFAULT_ENCODING, PARROT_DEFAULT_CHARSET,
            PObj_constant_FLAG);

        Parrot_str_free_cstring(cstring);
        VTABLE_set_pmc_keyed_str(interp, hll_info, const_name, entry);
    }
    else
        VTABLE_push_pmc(interp, hll_info, entry);

    VTABLE_set_integer_native(interp, entry, e_HLL_MAX);

    entry_id = constant_pmc_new(interp, enum_class_Integer);
    VTABLE_set_integer_native(interp, entry_id, id);
    VTABLE_set_pmc_keyed_int(interp, entry, e_HLL_id, entry_id);

    return entry;
}


/*

=item C<void Parrot_init_HLL(PARROT_INTERP)>

Initialises the HLL_info and HLL_namespace fields of the interpreter structure.
Registers the default HLL namespace "parrot".

=cut

*/

void
Parrot_init_HLL(PARROT_INTERP)
{
    ASSERT_ARGS(Parrot_init_HLL)
    interp->HLL_info      =
        constant_pmc_new(interp, enum_class_OrderedHash);
    interp->HLL_namespace =
        constant_pmc_new(interp, enum_class_ResizablePMCArray);

    Parrot_register_HLL(interp, CONST_STRING(interp, "parrot"));
}

/*

=item C<INTVAL Parrot_register_HLL(PARROT_INTERP, STRING *hll_name)>

Register the HLL with the given STRING name C<hll_name> in the interpreter.

If the HLL has already been registered, the ID of the HLL is returned.
Otherwise the HLL is registered, a corresponding HLL namespace is created,
and the HLL ID is returned.

If there is an error, C<-1> is returned.

=cut

*/

PARROT_EXPORT
INTVAL
Parrot_register_HLL(PARROT_INTERP, ARGIN(STRING *hll_name))
{
    ASSERT_ARGS(Parrot_register_HLL)
    PMC   *entry, *name, *type_hash, *ns_hash, *hll_info;
    INTVAL idx;

    /* TODO LOCK or disallow in threads */

    idx = Parrot_get_HLL_id(interp, hll_name);

    if (idx >= 0)
        return idx;

    hll_info = interp->HLL_info;

    START_WRITE_HLL_INFO(interp, hll_info);

    idx      = VTABLE_elements(interp, hll_info);
    entry    = new_hll_entry(interp, hll_name);

    /* register HLL name */
    name     = constant_pmc_new(interp, enum_class_String);

    VTABLE_set_string_native(interp, name, hll_name);
    VTABLE_set_pmc_keyed_int(interp, entry, e_HLL_name, name);

    /* create HLL namespace using the *constant* name */
    hll_name = Parrot_str_downcase(interp, VTABLE_get_string(interp, name));

    /* HLL type mappings aren't yet created, we can't create
     * a namespace in HLL's flavor yet - maybe promote the
     * ns_hash to another type, if mappings provide one
     * XXX - FIXME
     */
    ns_hash = Parrot_make_namespace_keyed_str(interp, interp->root_namespace,
                                              hll_name);

    /* cache HLL's toplevel namespace */
    VTABLE_set_pmc_keyed_int(interp, interp->HLL_namespace, idx, ns_hash);

    /* create HLL typemap hash */
    type_hash = constant_pmc_new(interp, enum_class_Hash);
    VTABLE_set_pointer(interp, type_hash, parrot_new_intval_hash(interp));
    VTABLE_set_pmc_keyed_int(interp, entry, e_HLL_typemap, type_hash);

    /* UNLOCK */
    END_WRITE_HLL_INFO(interp, hll_info);

    return idx;
}

/*

=item C<INTVAL Parrot_register_HLL_lib(PARROT_INTERP, STRING *hll_lib)>

Register an HLL library.
Takes a pointer to a library name STRING to add. If the name has already
been registered the list position of the library in the HLL Info list is
returned. Otherwise, the library is added to the list and 0 is returned.

=cut

*/

PARROT_EXPORT
INTVAL
Parrot_register_HLL_lib(PARROT_INTERP, ARGIN(STRING *hll_lib))
{
    ASSERT_ARGS(Parrot_register_HLL_lib)
    PMC   *hll_info = interp->HLL_info;
    PMC   *entry, *name;
    INTVAL nelements, i;

    START_WRITE_HLL_INFO(interp, hll_info);

    nelements = VTABLE_elements(interp, hll_info);

    for (i = 0; i < nelements; ++i) {
        PMC * const entry    = VTABLE_get_pmc_keyed_int(interp, hll_info, i);
        PMC * const lib_name = VTABLE_get_pmc_keyed_int(interp, entry, e_HLL_lib);

        if (!PMC_IS_NULL(lib_name)) {
            const STRING * const name = VTABLE_get_string(interp, lib_name);
            if (Parrot_str_equal(interp, name, hll_lib))
                break;
        }
    }

    if (i < nelements)
        return i;

    entry    = new_hll_entry(interp, NULL);

    VTABLE_set_pmc_keyed_int(interp, entry, e_HLL_name, PMCNULL);

    /* register dynlib */
    name    = constant_pmc_new(interp, enum_class_String);

    VTABLE_set_string_native(interp, name, hll_lib);
    VTABLE_set_pmc_keyed_int(interp, entry, e_HLL_lib, name);

    END_WRITE_HLL_INFO(interp, hll_info);

    return 0;
}

/*

=item C<INTVAL Parrot_get_HLL_id(PARROT_INTERP, STRING *hll_name)>

Returns the ID number of the HLL with the given name. The default HLL namespace
C<parrot> has an ID number of 0. On error, or if an HLL with the given name
does not exist, returns -1.

=cut

*/

PARROT_EXPORT
PARROT_WARN_UNUSED_RESULT
INTVAL
Parrot_get_HLL_id(PARROT_INTERP, ARGIN_NULLOK(STRING *hll_name))
{
    ASSERT_ARGS(Parrot_get_HLL_id)
    PMC * const hll_info = interp->HLL_info;
    INTVAL      i;

    START_READ_HLL_INFO(interp, hll_info);

    if (!hll_name || !VTABLE_exists_keyed_str(interp, hll_info, hll_name))
        i = -1;
    else {
        PMC * const entry    = VTABLE_get_pmc_keyed_str(interp, hll_info, hll_name);
        PMC * const entry_id = VTABLE_get_pmc_keyed_int(interp, entry, e_HLL_id);
        i = VTABLE_get_integer(interp, entry_id);
    }

    END_READ_HLL_INFO(interp, hll_info);

    return i;
}

/*

=item C<STRING * Parrot_get_HLL_name(PARROT_INTERP, INTVAL id)>

Returns the STRING name of the HLL with the given C<id> number. If the id
is out of range or does not exist, the NULL value is returned instead. Note
that some HLLs are anonymous and so might also return NULL.

=cut

*/

PARROT_EXPORT
PARROT_WARN_UNUSED_RESULT
PARROT_CAN_RETURN_NULL
STRING *
Parrot_get_HLL_name(PARROT_INTERP, INTVAL id)
{
    ASSERT_ARGS(Parrot_get_HLL_name)
    PMC * const  hll_info  = interp->HLL_info;
    const INTVAL nelements = VTABLE_elements(interp, hll_info);

    PMC         *entry, *name_pmc;

    if (id < 0 || id >= nelements)
        return NULL;

    START_READ_HLL_INFO(interp, hll_info);

    entry    = VTABLE_get_pmc_keyed_int(interp, hll_info, id);
    name_pmc = VTABLE_get_pmc_keyed_int(interp, entry, e_HLL_name);

    END_READ_HLL_INFO(interp, hll_info);

    /* loadlib-created 'HLL's are nameless */
    if (PMC_IS_NULL(name_pmc))
        return NULL;
    else
        return VTABLE_get_string(interp, name_pmc);
}

/*

=item C<void Parrot_register_HLL_type(PARROT_INTERP, INTVAL hll_id, INTVAL
core_type, INTVAL hll_type)>

Register a type mapping of C<< core_type => hll_type >> for the given HLL.

=cut

*/

PARROT_EXPORT
void
Parrot_register_HLL_type(PARROT_INTERP, INTVAL hll_id,
        INTVAL core_type, INTVAL hll_type)
{
    ASSERT_ARGS(Parrot_register_HLL_type)
    PMC  *entry, *type_hash;
    PMC  *hll_info = interp->HLL_info;
    const INTVAL n = VTABLE_elements(interp, hll_info);

    if (hll_id >= n)
        Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_GLOBAL_NOT_FOUND,
            "no such HLL ID (%vd)", hll_id);

    /* the type might already be registered in a non-conflicting way, in which
     * case we can avoid copying */
    if (PMC_sync(hll_info)) {
        if (hll_type == Parrot_get_HLL_type(interp, hll_id, core_type))
            return;
    }

    START_WRITE_HLL_INFO(interp, hll_info);

    entry     = VTABLE_get_pmc_keyed_int(interp, hll_info, hll_id);
    PARROT_ASSERT(!PMC_IS_NULL(entry));

    type_hash = VTABLE_get_pmc_keyed_int(interp, entry, e_HLL_typemap);
    PARROT_ASSERT(!PMC_IS_NULL(type_hash));

    VTABLE_set_integer_keyed_int(interp, type_hash, core_type, hll_type);

    END_WRITE_HLL_INFO(interp, hll_info);
}

/*

=item C<INTVAL Parrot_get_HLL_type(PARROT_INTERP, INTVAL hll_id, INTVAL
core_type)>

Get an equivalent HLL type number for the language C<hll_id>.  If the given HLL
doesn't remap the given type, or if C<hll_id> is the special value
C<PARROT_HLL_NONE>, returns C<core_type> unchanged.

=cut

*/

PARROT_EXPORT
INTVAL
Parrot_get_HLL_type(PARROT_INTERP, INTVAL hll_id, INTVAL core_type)
{
    ASSERT_ARGS(Parrot_get_HLL_type)
    PMC    *entry, *type_hash, *hll_info;
    INTVAL  n, id;

    if (hll_id == PARROT_HLL_NONE || hll_id == 0)
        return core_type;

    if (hll_id < 0)
        Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_GLOBAL_NOT_FOUND,
            "no such HLL ID (%vd)", hll_id);

    hll_info = interp->HLL_info;
    n        = VTABLE_elements(interp, hll_info);

    if (hll_id >= n)
        Parrot_ex_throw_from_c_args(interp, NULL, EXCEPTION_GLOBAL_NOT_FOUND,
            "no such HLL ID (%vd)", hll_id);

    START_READ_HLL_INFO(interp, hll_info);
    entry     = VTABLE_get_pmc_keyed_int(interp, hll_info, hll_id);
    END_READ_HLL_INFO(interp, hll_info);

    type_hash = VTABLE_get_pmc_keyed_int(interp, entry, e_HLL_typemap);

    if (PMC_IS_NULL(type_hash))
        return core_type;

    id = VTABLE_get_integer_keyed_int(interp, type_hash, core_type);

    return id ? id : core_type;
}

/*

=item C<INTVAL Parrot_get_ctx_HLL_type(PARROT_INTERP, INTVAL core_type)>

Return an equivalent PMC type number according to the HLL settings in
the current context.  If no type is registered, returns C<core_type>.

=cut

*/

PARROT_EXPORT
INTVAL
Parrot_get_ctx_HLL_type(PARROT_INTERP, INTVAL core_type)
{
    ASSERT_ARGS(Parrot_get_ctx_HLL_type)
    const INTVAL hll_id = CONTEXT(interp)->current_HLL;

    return Parrot_get_HLL_type(interp, hll_id, core_type);
}

/*

=item C<PMC* Parrot_get_ctx_HLL_namespace(PARROT_INTERP)>

Return root namespace of the current HLL.

=cut

*/

PARROT_EXPORT
PARROT_WARN_UNUSED_RESULT
PARROT_CAN_RETURN_NULL
PMC*
Parrot_get_ctx_HLL_namespace(PARROT_INTERP)
{
    ASSERT_ARGS(Parrot_get_ctx_HLL_namespace)
    return Parrot_get_HLL_namespace(interp, CONTEXT(interp)->current_HLL);
}

/*

=item C<PMC* Parrot_get_HLL_namespace(PARROT_INTERP, int hll_id)>

Return root namespace of the HLL with the ID of I<hll_id>.  If C<hll_id> is the
special value C<PARROT_HLL_NONE>, return the global root namespace.

=cut

*/

PARROT_EXPORT
PARROT_WARN_UNUSED_RESULT
PARROT_CAN_RETURN_NULL
PMC*
Parrot_get_HLL_namespace(PARROT_INTERP, int hll_id)
{
    ASSERT_ARGS(Parrot_get_HLL_namespace)
    if (hll_id == PARROT_HLL_NONE)
        return interp->root_namespace;

    return VTABLE_get_pmc_keyed_int(interp, interp->HLL_namespace, hll_id);
}

/*

=item C<void Parrot_regenerate_HLL_namespaces(PARROT_INTERP)>

Create all HLL namespaces that don't already exist. This is necessary when
creating a new interpreter which shares an old interpreter's HLL_info.

=cut

*/

PARROT_EXPORT
void
Parrot_regenerate_HLL_namespaces(PARROT_INTERP)
{
    ASSERT_ARGS(Parrot_regenerate_HLL_namespaces)
    const INTVAL n = VTABLE_elements(interp, interp->HLL_info);
    INTVAL       hll_id;

    /* start at one since the 'parrot' namespace should already have been
     * created */

    for (hll_id = 1; hll_id < n; ++hll_id) {
        PMC *ns_hash =
            VTABLE_get_pmc_keyed_int(interp, interp->HLL_namespace, hll_id);

        if (PMC_IS_NULL(ns_hash) ||
                ns_hash->vtable->base_type == enum_class_Undef)
        {
            STRING * const hll_name = Parrot_get_HLL_name(interp, hll_id);
            if (!hll_name)
                continue;

            Parrot_str_downcase_inplace(interp, hll_name);

            /* XXX as in Parrot_register_HLL() this needs to be fixed to use
             * the correct type of namespace. It's relatively easy to do that
             * here because the typemap already exists, but it is not currently
             * done for consistency.
             */
            ns_hash = Parrot_make_namespace_keyed_str(interp,
                interp->root_namespace, hll_name);

            VTABLE_set_pmc_keyed_int(interp, interp->HLL_namespace,
                                     hll_id, ns_hash);
        }
    }
}

/*

=back

=head1 AUTHOR

Leopold Toetsch

=cut

*/

/*
 * Local variables:
 *   c-file-style: "parrot"
 * End:
 * vim: expandtab shiftwidth=4:
 */