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guile/libguile/foreign.c
Andy Wingo 2b58dea2d2 (scheme foreign): API is less configuration-dependent 
* libguile/foreign.h:
* libguile/foreign.c: Always define complex-float and complex-double.
Fall back to alignof float / 2*sizeof float if no complex numbers.  (But
with C99 surely it exists everywhere.)
* module/system/foreign.scm (*writers*, *readers*): Always include
complex-float and complex-double readers and writers.
* test-suite/tests/foreign.test: Always run the complex tests.
2024-03-17 21:40:58 +01:00

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/* Copyright 2010-2016,2018,2024
Free Software Foundation, Inc.
This file is part of Guile.
Guile is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Guile is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public
License along with Guile. If not, see
<https://www.gnu.org/licenses/>. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include <alignof.h>
#include <alloca.h>
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <ffi.h>
#ifdef HAVE_COMPLEX_H
#include <complex.h>
#endif
#include "boolean.h"
#include "bytevectors.h"
#include "dynwind.h"
#include "eq.h"
#include "eval.h"
#include "extensions.h"
#include "finalizers.h"
#include "gsubr.h"
#include "instructions.h"
#include "intrinsics.h"
#include "keywords.h"
#include "list.h"
#include "modules.h"
#include "numbers.h"
#include "pairs.h"
#include "ports.h"
#include "stacks.h"
#include "symbols.h"
#include "threads.h"
#include "weak-table.h"
#include "version.h"
#include "foreign.h"
/* Return the first integer greater than or equal to LEN such that
LEN % ALIGN == 0. Return LEN if ALIGN is zero. */
#define ROUND_UP(len, align) \
((align) ? (((len) - 1UL) | ((align) - 1UL)) + 1UL : (len))
SCM_SYMBOL (sym_void, "void");
SCM_SYMBOL (sym_float, "float");
SCM_SYMBOL (sym_double, "double");
SCM_SYMBOL (sym_complex_float, "complex-float");
SCM_SYMBOL (sym_complex_double, "complex-double");
SCM_SYMBOL (sym_uint8, "uint8");
SCM_SYMBOL (sym_int8, "int8");
SCM_SYMBOL (sym_uint16, "uint16");
SCM_SYMBOL (sym_int16, "int16");
SCM_SYMBOL (sym_uint32, "uint32");
SCM_SYMBOL (sym_int32, "int32");
SCM_SYMBOL (sym_uint64, "uint64");
SCM_SYMBOL (sym_int64, "int64");
SCM_SYMBOL (sym_short, "short");
SCM_SYMBOL (sym_int, "int");
SCM_SYMBOL (sym_long, "long");
SCM_SYMBOL (sym_unsigned_short, "unsigned-short");
SCM_SYMBOL (sym_unsigned_int, "unsigned-int");
SCM_SYMBOL (sym_unsigned_long, "unsigned-long");
SCM_SYMBOL (sym_size_t, "size_t");
SCM_SYMBOL (sym_ssize_t, "ssize_t");
SCM_SYMBOL (sym_ptrdiff_t, "ptrdiff_t");
SCM_SYMBOL (sym_intptr_t, "intptr_t");
SCM_SYMBOL (sym_uintptr_t, "uintptr_t");
/* that's for pointers, you know. */
SCM_SYMBOL (sym_asterisk, "*");
SCM_SYMBOL (sym_null, "%null-pointer");
SCM_SYMBOL (sym_null_pointer_error, "null-pointer-error");
/* The cell representing the null pointer. */
static SCM null_pointer;
/* Raise a null pointer dereference error. */
static void
null_pointer_error (const char *func_name)
{
scm_error (sym_null_pointer_error, func_name,
"null pointer dereference", SCM_EOL, SCM_EOL);
}
static SCM cif_to_procedure (SCM cif, SCM func_ptr, int with_errno);
static SCM pointer_weak_refs = SCM_BOOL_F;
static void
register_weak_reference (SCM from, SCM to)
{
scm_weak_table_putq_x (pointer_weak_refs, from, to);
}
static void
pointer_finalizer_trampoline (void *ptr, void *data)
{
scm_t_pointer_finalizer finalizer = data;
finalizer (SCM_POINTER_VALUE (SCM_PACK_POINTER (ptr)));
}
SCM_DEFINE (scm_pointer_p, "pointer?", 1, 0, 0,
(SCM obj),
"Return @code{#t} if @var{obj} is a pointer object, "
"@code{#f} otherwise.\n")
#define FUNC_NAME s_scm_pointer_p
{
return scm_from_bool (SCM_POINTER_P (obj));
}
#undef FUNC_NAME
SCM_DEFINE (scm_make_pointer, "make-pointer", 1, 1, 0,
(SCM address, SCM finalizer),
"Return a foreign pointer object pointing to @var{address}. "
"If @var{finalizer} is passed, it should be a pointer to a "
"one-argument C function that will be called when the pointer "
"object becomes unreachable.")
#define FUNC_NAME s_scm_make_pointer
{
void *c_finalizer;
uintptr_t c_address;
c_address = scm_to_uintptr_t (address);
if (SCM_UNBNDP (finalizer))
c_finalizer = NULL;
else
{
SCM_VALIDATE_POINTER (2, finalizer);
c_finalizer = SCM_POINTER_VALUE (finalizer);
}
return scm_from_pointer ((void *) c_address, c_finalizer);
}
#undef FUNC_NAME
void *
scm_to_pointer (SCM pointer)
#define FUNC_NAME "scm_to_pointer"
{
SCM_VALIDATE_POINTER (1, pointer);
return SCM_POINTER_VALUE (pointer);
}
#undef FUNC_NAME
SCM
scm_from_pointer (void *ptr, scm_t_pointer_finalizer finalizer)
{
SCM ret;
if (ptr == NULL && finalizer == NULL)
ret = null_pointer;
else
{
ret = scm_cell (scm_tc7_pointer, (scm_t_bits) ptr);
if (finalizer)
scm_i_set_finalizer (SCM2PTR (ret), pointer_finalizer_trampoline,
finalizer);
}
return ret;
}
SCM_DEFINE (scm_pointer_address, "pointer-address", 1, 0, 0,
(SCM pointer),
"Return the numerical value of @var{pointer}.")
#define FUNC_NAME s_scm_pointer_address
{
SCM_VALIDATE_POINTER (1, pointer);
return scm_from_uintptr_t ((uintptr_t) SCM_POINTER_VALUE (pointer));
}
#undef FUNC_NAME
SCM_DEFINE (scm_pointer_to_scm, "pointer->scm", 1, 0, 0,
(SCM pointer),
"Unsafely cast @var{pointer} to a Scheme object.\n"
"Cross your fingers!")
#define FUNC_NAME s_scm_pointer_to_scm
{
SCM_VALIDATE_POINTER (1, pointer);
return SCM_PACK ((scm_t_bits) SCM_POINTER_VALUE (pointer));
}
#undef FUNC_NAME
SCM_DEFINE (scm_scm_to_pointer, "scm->pointer", 1, 0, 0,
(SCM scm),
"Return a foreign pointer object with the @code{object-address}\n"
"of @var{scm}.")
#define FUNC_NAME s_scm_scm_to_pointer
{
SCM ret;
ret = scm_from_pointer ((void*) SCM_UNPACK (scm), NULL);
if (SCM_HEAP_OBJECT_P (ret))
register_weak_reference (ret, scm);
return ret;
}
#undef FUNC_NAME
SCM_DEFINE (scm_pointer_to_bytevector, "pointer->bytevector", 2, 2, 0,
(SCM pointer, SCM len, SCM offset, SCM uvec_type),
"Return a bytevector aliasing the @var{len} bytes pointed\n"
"to by @var{pointer}.\n\n"
"The user may specify an alternate default interpretation for\n"
"the memory by passing the @var{uvec_type} argument, to indicate\n"
"that the memory is an array of elements of that type.\n"
"@var{uvec_type} should be something that\n"
"@code{uniform-vector-element-type} would return, like @code{f32}\n"
"or @code{s16}.\n\n"
"When @var{offset} is passed, it specifies the offset in bytes\n"
"relative to @var{pointer} of the memory region aliased by the\n"
"returned bytevector.")
#define FUNC_NAME s_scm_pointer_to_bytevector
{
SCM ret;
int8_t *ptr;
size_t boffset, blen;
scm_t_array_element_type btype;
SCM_VALIDATE_POINTER (1, pointer);
ptr = SCM_POINTER_VALUE (pointer);
if (SCM_UNLIKELY (ptr == NULL))
null_pointer_error (FUNC_NAME);
if (SCM_UNBNDP (uvec_type))
btype = SCM_ARRAY_ELEMENT_TYPE_VU8;
else
{
int i;
for (i = 0; i <= SCM_ARRAY_ELEMENT_TYPE_LAST; i++)
if (scm_is_eq (uvec_type, scm_i_array_element_types[i]))
break;
switch (i)
{
case SCM_ARRAY_ELEMENT_TYPE_VU8:
case SCM_ARRAY_ELEMENT_TYPE_U8:
case SCM_ARRAY_ELEMENT_TYPE_S8:
case SCM_ARRAY_ELEMENT_TYPE_U16:
case SCM_ARRAY_ELEMENT_TYPE_S16:
case SCM_ARRAY_ELEMENT_TYPE_U32:
case SCM_ARRAY_ELEMENT_TYPE_S32:
case SCM_ARRAY_ELEMENT_TYPE_U64:
case SCM_ARRAY_ELEMENT_TYPE_S64:
case SCM_ARRAY_ELEMENT_TYPE_F32:
case SCM_ARRAY_ELEMENT_TYPE_F64:
case SCM_ARRAY_ELEMENT_TYPE_C32:
case SCM_ARRAY_ELEMENT_TYPE_C64:
btype = i;
break;
default:
scm_wrong_type_arg_msg (FUNC_NAME, SCM_ARG1, uvec_type,
"uniform vector type");
}
}
if (SCM_UNBNDP (offset))
boffset = 0;
else
boffset = scm_to_size_t (offset);
blen = scm_to_size_t (len);
ret = scm_c_take_typed_bytevector ((signed char *) ptr + boffset,
blen, btype, pointer);
return ret;
}
#undef FUNC_NAME
SCM_DEFINE (scm_bytevector_to_pointer, "bytevector->pointer", 1, 1, 0,
(SCM bv, SCM offset),
"Return a pointer pointer aliasing the memory pointed to by\n"
"@var{bv} or @var{offset} bytes after @var{bv} when @var{offset}\n"
"is passed.")
#define FUNC_NAME s_scm_bytevector_to_pointer
{
SCM ret;
signed char *ptr;
size_t boffset;
SCM_VALIDATE_BYTEVECTOR (1, bv);
ptr = SCM_BYTEVECTOR_CONTENTS (bv);
if (SCM_UNBNDP (offset))
boffset = 0;
else
boffset = scm_to_unsigned_integer (offset, 0,
SCM_BYTEVECTOR_LENGTH (bv) - 1);
ret = scm_from_pointer (ptr + boffset, NULL);
register_weak_reference (ret, bv);
return ret;
}
#undef FUNC_NAME
SCM_DEFINE (scm_set_pointer_finalizer_x, "set-pointer-finalizer!", 2, 0, 0,
(SCM pointer, SCM finalizer),
"Arrange for the C procedure wrapped by @var{finalizer} to be\n"
"called on the pointer wrapped by @var{pointer} when @var{pointer}\n"
"becomes unreachable. Note: the C procedure should not call into\n"
"Scheme. If you need a Scheme finalizer, use guardians.")
#define FUNC_NAME s_scm_set_pointer_finalizer_x
{
SCM_VALIDATE_POINTER (1, pointer);
SCM_VALIDATE_POINTER (2, finalizer);
scm_i_add_finalizer (SCM2PTR (pointer), pointer_finalizer_trampoline,
SCM_POINTER_VALUE (finalizer));
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
void
scm_i_pointer_print (SCM pointer, SCM port, scm_print_state *pstate)
{
scm_puts ("#<pointer 0x", port);
scm_uintprint (scm_to_uintptr_t (scm_pointer_address (pointer)), 16, port);
scm_putc ('>', port);
}
/* Non-primitive helpers functions. These procedures could be
implemented in terms of the primitives above but would be inefficient
(heap allocation overhead, Scheme/C round trips, etc.) */
SCM_DEFINE (scm_dereference_pointer, "dereference-pointer", 1, 0, 0,
(SCM pointer),
"Assuming @var{pointer} points to a memory region that\n"
"holds a pointer, return this pointer.")
#define FUNC_NAME s_scm_dereference_pointer
{
void **ptr;
SCM_VALIDATE_POINTER (1, pointer);
ptr = SCM_POINTER_VALUE (pointer);
if (SCM_UNLIKELY (ptr == NULL))
null_pointer_error (FUNC_NAME);
return scm_from_pointer (*ptr, NULL);
}
#undef FUNC_NAME
SCM_DEFINE (scm_string_to_pointer, "string->pointer", 1, 1, 0,
(SCM string, SCM encoding),
"Return a foreign pointer to a nul-terminated copy of\n"
"@var{string} in the given @var{encoding}, defaulting to\n"
"the current locale encoding. The C string is freed when\n"
"the returned foreign pointer becomes unreachable.\n\n"
"This is the Scheme equivalent of @code{scm_to_stringn}.")
#define FUNC_NAME s_scm_string_to_pointer
{
SCM_VALIDATE_STRING (1, string);
/* XXX: Finalizers slow down libgc; they could be avoided if
`scm_to_string' & co. were able to use libgc-allocated memory. */
if (SCM_UNBNDP (encoding))
return scm_from_pointer (scm_to_locale_string (string), free);
else
{
char *enc;
SCM ret;
SCM_VALIDATE_STRING (2, encoding);
enc = scm_to_locale_string (encoding);
scm_dynwind_begin (0);
scm_dynwind_free (enc);
ret = scm_from_pointer
(scm_to_stringn (string, NULL, enc,
scm_i_default_string_failed_conversion_handler ()),
free);
scm_dynwind_end ();
return ret;
}
}
#undef FUNC_NAME
SCM_DEFINE (scm_pointer_to_string, "pointer->string", 1, 2, 0,
(SCM pointer, SCM length, SCM encoding),
"Return the string representing the C string pointed to by\n"
"@var{pointer}. If @var{length} is omitted or @code{-1}, the\n"
"string is assumed to be nul-terminated. Otherwise\n"
"@var{length} is the number of bytes in memory pointed to by\n"
"@var{pointer}. The C string is assumed to be in the given\n"
"@var{encoding}, defaulting to the current locale encoding.\n\n"
"This is the Scheme equivalent of @code{scm_from_stringn}.")
#define FUNC_NAME s_scm_pointer_to_string
{
size_t len;
SCM_VALIDATE_POINTER (1, pointer);
if (SCM_UNBNDP (length)
|| scm_is_true (scm_eqv_p (length, scm_from_int (-1))))
len = (size_t)-1;
else
len = scm_to_size_t (length);
if (SCM_UNBNDP (encoding))
return scm_from_locale_stringn (SCM_POINTER_VALUE (pointer), len);
else
{
char *enc;
SCM ret;
SCM_VALIDATE_STRING (3, encoding);
enc = scm_to_locale_string (encoding);
scm_dynwind_begin (0);
scm_dynwind_free (enc);
ret = scm_from_stringn (SCM_POINTER_VALUE (pointer), len, enc,
scm_i_default_string_failed_conversion_handler ());
scm_dynwind_end ();
return ret;
}
}
#undef FUNC_NAME
SCM_DEFINE (scm_alignof, "alignof", 1, 0, 0, (SCM type),
"Return the alignment of @var{type}, in bytes.\n\n"
"@var{type} should be a valid C type, like @code{int}.\n"
"Alternately @var{type} may be the symbol @code{*}, in which\n"
"case the alignment of a pointer is returned. @var{type} may\n"
"also be a list of types, in which case the alignment of a\n"
"@code{struct} with ABI-conventional packing is returned.")
#define FUNC_NAME s_scm_alignof
{
if (SCM_I_INUMP (type))
{
switch (SCM_I_INUM (type))
{
case SCM_FOREIGN_TYPE_FLOAT:
return scm_from_size_t (alignof_type (float));
case SCM_FOREIGN_TYPE_DOUBLE:
return scm_from_size_t (alignof_type (double));
case SCM_FOREIGN_TYPE_COMPLEX_FLOAT:
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
return scm_from_size_t (alignof_type (float _Complex));
#else
return scm_from_size_t (alignof_type (float));
#endif
case SCM_FOREIGN_TYPE_COMPLEX_DOUBLE:
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
return scm_from_size_t (alignof_type (double _Complex));
#else
return scm_from_size_t (alignof_type (double));
#endif
case SCM_FOREIGN_TYPE_UINT8:
return scm_from_size_t (alignof_type (uint8_t));
case SCM_FOREIGN_TYPE_INT8:
return scm_from_size_t (alignof_type (int8_t));
case SCM_FOREIGN_TYPE_UINT16:
return scm_from_size_t (alignof_type (uint16_t));
case SCM_FOREIGN_TYPE_INT16:
return scm_from_size_t (alignof_type (int16_t));
case SCM_FOREIGN_TYPE_UINT32:
return scm_from_size_t (alignof_type (uint32_t));
case SCM_FOREIGN_TYPE_INT32:
return scm_from_size_t (alignof_type (int32_t));
case SCM_FOREIGN_TYPE_UINT64:
return scm_from_size_t (alignof_type (uint64_t));
case SCM_FOREIGN_TYPE_INT64:
return scm_from_size_t (alignof_type (int64_t));
default:
scm_wrong_type_arg (FUNC_NAME, 1, type);
}
}
else if (scm_is_eq (type, sym_asterisk))
/* a pointer */
return scm_from_size_t (alignof_type (void*));
else if (scm_is_pair (type))
{
/* TYPE is a structure. Section 3-3 of the i386, x86_64, PowerPC,
and SPARC P.S. of the System V ABI all say: "Aggregates
(structures and arrays) and unions assume the alignment of
their most strictly aligned component." */
size_t max;
for (max = 0; scm_is_pair (type); type = SCM_CDR (type))
{
size_t align;
align = scm_to_size_t (scm_alignof (SCM_CAR (type)));
if (align > max)
max = align;
}
return scm_from_size_t (max);
}
else
scm_wrong_type_arg (FUNC_NAME, 1, type);
}
#undef FUNC_NAME
SCM_DEFINE (scm_sizeof, "sizeof", 1, 0, 0, (SCM type),
"Return the size of @var{type}, in bytes.\n\n"
"@var{type} should be a valid C type, like @code{int}.\n"
"Alternately @var{type} may be the symbol @code{*}, in which\n"
"case the size of a pointer is returned. @var{type} may also\n"
"be a list of types, in which case the size of a @code{struct}\n"
"with ABI-conventional packing is returned.")
#define FUNC_NAME s_scm_sizeof
{
if (SCM_I_INUMP (type))
{
switch (SCM_I_INUM (type))
{
case SCM_FOREIGN_TYPE_FLOAT:
return scm_from_size_t (sizeof (float));
case SCM_FOREIGN_TYPE_DOUBLE:
return scm_from_size_t (sizeof (double));
case SCM_FOREIGN_TYPE_COMPLEX_FLOAT:
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
return scm_from_size_t (sizeof (float _Complex));
#else
return scm_from_size_t (2 * sizeof (float));
#endif
case SCM_FOREIGN_TYPE_COMPLEX_DOUBLE:
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
return scm_from_size_t (sizeof (double _Complex));
#else
return scm_from_size_t (2 * sizeof (double));
#endif
case SCM_FOREIGN_TYPE_UINT8:
return scm_from_size_t (sizeof (uint8_t));
case SCM_FOREIGN_TYPE_INT8:
return scm_from_size_t (sizeof (int8_t));
case SCM_FOREIGN_TYPE_UINT16:
return scm_from_size_t (sizeof (uint16_t));
case SCM_FOREIGN_TYPE_INT16:
return scm_from_size_t (sizeof (int16_t));
case SCM_FOREIGN_TYPE_UINT32:
return scm_from_size_t (sizeof (uint32_t));
case SCM_FOREIGN_TYPE_INT32:
return scm_from_size_t (sizeof (int32_t));
case SCM_FOREIGN_TYPE_UINT64:
return scm_from_size_t (sizeof (uint64_t));
case SCM_FOREIGN_TYPE_INT64:
return scm_from_size_t (sizeof (int64_t));
default:
scm_wrong_type_arg (FUNC_NAME, 1, type);
}
}
else if (scm_is_eq (type, sym_asterisk))
/* a pointer */
return scm_from_size_t (sizeof (void*));
else if (scm_is_pair (type))
{
/* a struct */
size_t off = 0;
size_t align = scm_to_size_t (scm_alignof(type));
while (scm_is_pair (type))
{
off = ROUND_UP (off, scm_to_size_t (scm_alignof (scm_car (type))));
off += scm_to_size_t (scm_sizeof (scm_car (type)));
type = scm_cdr (type);
}
return scm_from_size_t (ROUND_UP(off, align));
}
else
scm_wrong_type_arg (FUNC_NAME, 1, type);
}
#undef FUNC_NAME
/* return 1 on success, 0 on failure */
static int
parse_ffi_type (SCM type, int return_p, long *n_structs, long *n_struct_elts)
{
if (SCM_I_INUMP (type))
{
if ((SCM_I_INUM (type) < 0 )
|| (SCM_I_INUM (type) > SCM_FOREIGN_TYPE_LAST))
return 0;
else if (SCM_I_INUM (type) == SCM_FOREIGN_TYPE_VOID && !return_p)
return 0;
#ifndef FFI_TARGET_HAS_COMPLEX_TYPE
/* The complex types are always defined so they can be used when
accessing data, but some targets don't support them as
arguments or return values. */
else if (SCM_I_INUM (type) == SCM_FOREIGN_TYPE_COMPLEX_FLOAT
|| SCM_I_INUM (type) == SCM_FOREIGN_TYPE_COMPLEX_DOUBLE)
return 0;
#endif
else
return 1;
}
else if (scm_is_eq (type, sym_asterisk))
/* a pointer */
return 1;
else
{
long len;
len = scm_ilength (type);
if (len < 1)
return 0;
while (len--)
{
if (!parse_ffi_type (scm_car (type), 0, n_structs, n_struct_elts))
return 0;
(*n_struct_elts)++;
type = scm_cdr (type);
}
(*n_structs)++;
return 1;
}
}
static void
fill_ffi_type (SCM type, ffi_type *ftype, ffi_type ***type_ptrs,
ffi_type **types)
{
if (SCM_I_INUMP (type))
{
switch (SCM_I_INUM (type))
{
case SCM_FOREIGN_TYPE_FLOAT:
*ftype = ffi_type_float;
return;
case SCM_FOREIGN_TYPE_DOUBLE:
*ftype = ffi_type_double;
return;
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
case SCM_FOREIGN_TYPE_COMPLEX_FLOAT:
*ftype = ffi_type_complex_float;
return;
case SCM_FOREIGN_TYPE_COMPLEX_DOUBLE:
*ftype = ffi_type_complex_double;
return;
#endif
case SCM_FOREIGN_TYPE_UINT8:
*ftype = ffi_type_uint8;
return;
case SCM_FOREIGN_TYPE_INT8:
*ftype = ffi_type_sint8;
return;
case SCM_FOREIGN_TYPE_UINT16:
*ftype = ffi_type_uint16;
return;
case SCM_FOREIGN_TYPE_INT16:
*ftype = ffi_type_sint16;
return;
case SCM_FOREIGN_TYPE_UINT32:
*ftype = ffi_type_uint32;
return;
case SCM_FOREIGN_TYPE_INT32:
*ftype = ffi_type_sint32;
return;
case SCM_FOREIGN_TYPE_UINT64:
*ftype = ffi_type_uint64;
return;
case SCM_FOREIGN_TYPE_INT64:
*ftype = ffi_type_sint64;
return;
case SCM_FOREIGN_TYPE_VOID:
*ftype = ffi_type_void;
return;
default:
scm_wrong_type_arg_msg ("pointer->procedure", 0, type,
"foreign type");
}
}
else if (scm_is_eq (type, sym_asterisk))
/* a pointer */
{
*ftype = ffi_type_pointer;
return;
}
else
{
long i, len;
len = scm_ilength (type);
ftype->size = 0;
ftype->alignment = 0;
ftype->type = FFI_TYPE_STRUCT;
ftype->elements = *type_ptrs;
*type_ptrs += len + 1;
for (i = 0; i < len; i++)
{
ftype->elements[i] = *types;
*types += 1;
fill_ffi_type (scm_car (type), ftype->elements[i],
type_ptrs, types);
type = scm_cdr (type);
}
ftype->elements[i] = NULL;
}
}
/* Return a "cif" (call interface) for the given RETURN_TYPE and
ARG_TYPES. */
static ffi_cif *
make_cif (SCM return_type, SCM arg_types, const char *caller)
#define FUNC_NAME caller
{
SCM walk;
long i, nargs, n_structs, n_struct_elts;
size_t cif_len;
char *mem;
ffi_cif *cif;
ffi_type **type_ptrs;
ffi_type *types;
nargs = scm_ilength (arg_types);
SCM_ASSERT (nargs >= 0, arg_types, 3, FUNC_NAME);
/* fixme: assert nargs < 1<<32 */
n_structs = n_struct_elts = 0;
/* For want of talloc, we're going to have to do this in two passes: first we
figure out how much memory is needed for all types, then we allocate the
cif and the types all in one block. */
if (!parse_ffi_type (return_type, 1, &n_structs, &n_struct_elts))
scm_wrong_type_arg (FUNC_NAME, 1, return_type);
for (walk = arg_types; scm_is_pair (walk); walk = scm_cdr (walk))
if (!parse_ffi_type (scm_car (walk), 0, &n_structs, &n_struct_elts))
scm_wrong_type_arg (FUNC_NAME, 3, scm_car (walk));
/* the memory: with space for the cif itself */
cif_len = sizeof (ffi_cif);
/* then ffi_type pointers: one for each arg, one for each struct
element, and one for each struct (for null-termination) */
cif_len = (ROUND_UP (cif_len, alignof_type (void *))
+ (nargs + n_structs + n_struct_elts)*sizeof(void*));
/* then the ffi_type structs themselves, one per arg and struct element, and
one for the return val */
cif_len = (ROUND_UP (cif_len, alignof_type (ffi_type))
+ (nargs + n_struct_elts + 1)*sizeof(ffi_type));
mem = scm_gc_malloc_pointerless (cif_len, "foreign");
/* ensure all the memory is initialized, even the holes */
memset (mem, 0, cif_len);
cif = (ffi_cif *) mem;
/* reuse cif_len to walk through the mem */
cif_len = ROUND_UP (sizeof (ffi_cif), alignof_type (void *));
type_ptrs = (ffi_type**)(mem + cif_len);
cif_len = ROUND_UP (cif_len
+ (nargs + n_structs + n_struct_elts)*sizeof(void*),
alignof_type (ffi_type));
types = (ffi_type*)(mem + cif_len);
/* whew. now knit the pointers together. */
cif->rtype = types++;
fill_ffi_type (return_type, cif->rtype, &type_ptrs, &types);
cif->arg_types = type_ptrs;
type_ptrs += nargs;
for (walk = arg_types, i = 0; scm_is_pair (walk); walk = scm_cdr (walk), i++)
{
cif->arg_types[i] = types++;
fill_ffi_type (scm_car (walk), cif->arg_types[i], &type_ptrs, &types);
}
/* round out the cif, and we're done. */
cif->abi = FFI_DEFAULT_ABI;
cif->nargs = nargs;
cif->bytes = 0;
cif->flags = 0;
if (FFI_OK != ffi_prep_cif (cif, FFI_DEFAULT_ABI, cif->nargs, cif->rtype,
cif->arg_types))
SCM_MISC_ERROR ("ffi_prep_cif failed", SCM_EOL);
return cif;
}
#undef FUNC_NAME
static SCM
pointer_to_procedure (SCM return_type, SCM func_ptr, SCM arg_types,
int with_errno)
#define FUNC_NAME "pointer->procedure"
{
ffi_cif *cif;
SCM_VALIDATE_POINTER (2, func_ptr);
cif = make_cif (return_type, arg_types, FUNC_NAME);
return cif_to_procedure (scm_from_pointer (cif, NULL), func_ptr,
with_errno);
}
#undef FUNC_NAME
SCM
scm_pointer_to_procedure (SCM return_type, SCM func_ptr, SCM arg_types)
{
return pointer_to_procedure (return_type, func_ptr, arg_types, 0);
}
SCM
scm_pointer_to_procedure_with_errno (SCM return_type, SCM func_ptr,
SCM arg_types)
{
return pointer_to_procedure (return_type, func_ptr, arg_types, 1);
}
SCM_KEYWORD (k_return_errno, "return-errno?");
SCM_INTERNAL SCM scm_i_pointer_to_procedure (SCM, SCM, SCM, SCM);
SCM_DEFINE (scm_i_pointer_to_procedure, "pointer->procedure", 3, 0, 1,
(SCM return_type, SCM func_ptr, SCM arg_types, SCM keyword_args),
"Make a foreign function.\n\n"
"Given the foreign void pointer @var{func_ptr}, its argument and\n"
"return types @var{arg_types} and @var{return_type}, return a\n"
"procedure that will pass arguments to the foreign function\n"
"and return appropriate values.\n\n"
"@var{arg_types} should be a list of foreign types.\n"
"@code{return_type} should be a foreign type.\n"
"If the @code{#:return-errno?} keyword argument is provided and\n"
"its value is true, then the returned procedure will return two\n"
"values, with @code{errno} as the second value.")
#define FUNC_NAME s_scm_i_pointer_to_procedure
{
SCM return_errno = SCM_BOOL_F;
scm_c_bind_keyword_arguments (FUNC_NAME, keyword_args, 0,
k_return_errno, &return_errno,
SCM_UNDEFINED);
return pointer_to_procedure (return_type, func_ptr, arg_types,
scm_to_bool (return_errno));
}
#undef FUNC_NAME
static const uint32_t *
get_foreign_stub_code (unsigned int nargs, int with_errno)
{
size_t i;
size_t code_len = with_errno ? 4 : 5;
uint32_t *ret, *code;
if (nargs >= (1 << 24) + 1)
scm_misc_error ("make-foreign-function", "too many arguments: ~a",
scm_list_1 (scm_from_uint (nargs)));
ret = scm_i_alloc_primitive_code_with_instrumentation (code_len, &code);
i = 0;
code[i++] = SCM_PACK_OP_24 (assert_nargs_ee, nargs + 1);
code[i++] = SCM_PACK_OP_12_12 (foreign_call, 0, 1);
code[i++] = SCM_PACK_OP_24 (handle_interrupts, 0);
if (!with_errno)
code[i++] = SCM_PACK_OP_24 (reset_frame, 1);
code[i++] = SCM_PACK_OP_24 (return_values, 0);
return ret;
}
static SCM
cif_to_procedure (SCM cif, SCM func_ptr, int with_errno)
{
ffi_cif *c_cif;
SCM ret;
scm_t_bits nfree = 2;
scm_t_bits flags = SCM_F_PROGRAM_IS_FOREIGN;
c_cif = (ffi_cif *) SCM_POINTER_VALUE (cif);
ret = scm_words (scm_tc7_program | (nfree << 16) | flags, nfree + 2);
SCM_SET_CELL_WORD_1 (ret, get_foreign_stub_code (c_cif->nargs, with_errno));
SCM_PROGRAM_FREE_VARIABLE_SET (ret, 0, cif);
SCM_PROGRAM_FREE_VARIABLE_SET (ret, 1, func_ptr);
return ret;
}
/* Set *LOC to the foreign representation of X with TYPE. */
static void
unpack (const ffi_type *type, void *loc, SCM x, int return_value_p)
#define FUNC_NAME "foreign-call"
{
switch (type->type)
{
case FFI_TYPE_FLOAT:
*(float *) loc = scm_to_double (x);
break;
case FFI_TYPE_DOUBLE:
*(double *) loc = scm_to_double (x);
break;
/* no FFI_TYPE_xxx_COMPLEX or (FFI_TYPE_COMPLEX_xxx) :-| */
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
case FFI_TYPE_COMPLEX:
{
double re = scm_to_double (scm_real_part(x));
double im = scm_to_double (scm_imag_part(x));
if (sizeof (float _Complex) == type->size)
*(float _Complex *) loc = (float)re + _Complex_I * (float)im;
else if (sizeof (double _Complex) == type->size)
*(double _Complex *) loc = re + _Complex_I * im;
else
abort();
}
break;
#endif
/* For integer return values smaller than `int', libffi expects the
result in an `ffi_arg'-long buffer. */
case FFI_TYPE_UINT8:
if (return_value_p)
*(ffi_arg *) loc = scm_to_uint8 (x);
else
*(uint8_t *) loc = scm_to_uint8 (x);
break;
case FFI_TYPE_SINT8:
if (return_value_p)
*(ffi_arg *) loc = scm_to_int8 (x);
else
*(int8_t *) loc = scm_to_int8 (x);
break;
case FFI_TYPE_UINT16:
if (return_value_p)
*(ffi_arg *) loc = scm_to_uint16 (x);
else
*(uint16_t *) loc = scm_to_uint16 (x);
break;
case FFI_TYPE_SINT16:
if (return_value_p)
*(ffi_arg *) loc = scm_to_int16 (x);
else
*(int16_t *) loc = scm_to_int16 (x);
break;
case FFI_TYPE_UINT32:
if (return_value_p)
*(ffi_arg *) loc = scm_to_uint32 (x);
else
*(uint32_t *) loc = scm_to_uint32 (x);
break;
case FFI_TYPE_SINT32:
if (return_value_p)
*(ffi_arg *) loc = scm_to_int32 (x);
else
*(int32_t *) loc = scm_to_int32 (x);
break;
case FFI_TYPE_UINT64:
*(uint64_t *) loc = scm_to_uint64 (x);
break;
case FFI_TYPE_SINT64:
*(int64_t *) loc = scm_to_int64 (x);
break;
case FFI_TYPE_STRUCT:
SCM_VALIDATE_POINTER (1, x);
memcpy (loc, SCM_POINTER_VALUE (x), type->size);
break;
case FFI_TYPE_POINTER:
SCM_VALIDATE_POINTER (1, x);
*(void **) loc = SCM_POINTER_VALUE (x);
break;
case FFI_TYPE_VOID:
/* Do nothing. */
break;
default:
abort ();
}
}
#undef FUNC_NAME
/* Return a Scheme representation of the foreign value at LOC of type
TYPE. When RETURN_VALUE_P is true, LOC is assumed to point to a
return value buffer; otherwise LOC is assumed to point to an
argument buffer. */
static SCM
pack (const ffi_type * type, const void *loc, int return_value_p)
{
switch (type->type)
{
case FFI_TYPE_VOID:
return SCM_UNSPECIFIED;
case FFI_TYPE_FLOAT:
return scm_from_double (*(float *) loc);
case FFI_TYPE_DOUBLE:
return scm_from_double (*(double *) loc);
/* no FFI_TYPE_xxx_COMPLEX or (FFI_TYPE_COMPLEX_xxx) :-| */
#ifdef FFI_TARGET_HAS_COMPLEX_TYPE
case FFI_TYPE_COMPLEX:
{
double re, im;
if (sizeof (float _Complex) == type->size)
{
re = crealf(*(float _Complex *) loc);
im = cimagf(*(float _Complex *) loc);
}
else if (sizeof (double _Complex) == type->size)
{
re = creal(*(double _Complex *) loc);
im = cimag(*(double _Complex *) loc);
}
else
abort ();
return scm_make_rectangular (scm_from_double (re), scm_from_double (im));
}
#endif
/* For integer return values smaller than `int', libffi stores the
result in an `ffi_arg'-long buffer, of which only the
significant bits must be kept---hence the pair of casts below.
See <http://thread.gmane.org/gmane.comp.lib.ffi.general/406>
for details. */
case FFI_TYPE_UINT8:
if (return_value_p)
return scm_from_uint8 ((uint8_t) *(ffi_arg *) loc);
else
return scm_from_uint8 (* (uint8_t *) loc);
case FFI_TYPE_SINT8:
if (return_value_p)
return scm_from_int8 ((int8_t) *(ffi_arg *) loc);
else
return scm_from_int8 (* (int8_t *) loc);
case FFI_TYPE_UINT16:
if (return_value_p)
return scm_from_uint16 ((uint16_t) *(ffi_arg *) loc);
else
return scm_from_uint16 (* (uint16_t *) loc);
case FFI_TYPE_SINT16:
if (return_value_p)
return scm_from_int16 ((int16_t) *(ffi_arg *) loc);
else
return scm_from_int16 (* (int16_t *) loc);
case FFI_TYPE_UINT32:
if (return_value_p)
return scm_from_uint32 ((uint32_t) *(ffi_arg *) loc);
else
return scm_from_uint32 (* (uint32_t *) loc);
case FFI_TYPE_SINT32:
if (return_value_p)
return scm_from_int32 ((int32_t) *(ffi_arg *) loc);
else
return scm_from_int32 (* (int32_t *) loc);
case FFI_TYPE_UINT64:
return scm_from_uint64 (*(uint64_t *) loc);
case FFI_TYPE_SINT64:
return scm_from_int64 (*(int64_t *) loc);
case FFI_TYPE_STRUCT:
{
void *mem = scm_gc_malloc_pointerless (type->size, "foreign");
memcpy (mem, loc, type->size);
return scm_from_pointer (mem, NULL);
}
case FFI_TYPE_POINTER:
return scm_from_pointer (*(void **) loc, NULL);
default:
abort ();
}
}
#define MAX(A, B) ((A) >= (B) ? (A) : (B))
SCM
scm_i_foreign_call (SCM cif_scm, SCM pointer_scm, int *errno_ret,
const union scm_vm_stack_element *argv)
{
/* FOREIGN is the pair that cif_to_procedure set as the 0th element of the
objtable. */
ffi_cif *cif;
void (*func) (void);
uint8_t *data;
void *rvalue;
void **args;
unsigned i;
size_t arg_size;
ptrdiff_t off;
cif = SCM_POINTER_VALUE (cif_scm);
func = SCM_POINTER_VALUE (pointer_scm);
/* Argument pointers. */
args = alloca (sizeof (void *) * cif->nargs);
/* Compute the worst-case amount of memory needed to store all the argument
values. Note: as of libffi 3.0.9 `cif->bytes' is undocumented and is zero,
so it can't be used for that purpose. */
for (i = 0, arg_size = 0; i < cif->nargs; i++)
arg_size += cif->arg_types[i]->size + cif->arg_types[i]->alignment - 1;
/* Space for argument values, followed by return value. */
data = alloca (arg_size + cif->rtype->size
+ MAX (sizeof (void *), cif->rtype->alignment));
/* Unpack ARGV to native values, setting ARGV pointers. */
for (i = 0, off = 0;
i < cif->nargs;
off = (uint8_t *) args[i] - data + cif->arg_types[i]->size,
i++)
{
/* Suitably align the storage area for argument I. */
args[i] = (void *) ROUND_UP ((uintptr_t) data + off,
cif->arg_types[i]->alignment);
assert ((uintptr_t) args[i] % cif->arg_types[i]->alignment == 0);
unpack (cif->arg_types[i], args[i], argv[cif->nargs - i - 1].as_scm, 0);
}
/* Prepare space for the return value. On some platforms, such as
`armv5tel-*-linux-gnueabi', the return value has to be at least
word-aligned, even if its type doesn't have any alignment requirement as is
the case with `char'. */
rvalue = (void *) ROUND_UP ((uintptr_t) data + off,
MAX (sizeof (void *), cif->rtype->alignment));
/* off we go! */
errno = 0;
ffi_call (cif, func, rvalue, args);
*errno_ret = errno;
return pack (cif->rtype, rvalue, 1);
}
/* Function pointers aka. "callbacks" or "closures". */
#ifdef FFI_CLOSURES
/* Trampoline to invoke a libffi closure that wraps a Scheme
procedure. */
static void
invoke_closure (ffi_cif *cif, void *ret, void **args, void *data)
{
size_t i;
SCM proc, *argv, result;
proc = SCM_PACK_POINTER (data);
argv = alloca (cif->nargs * sizeof (*argv));
/* Pack ARGS to SCM values, setting ARGV pointers. */
for (i = 0; i < cif->nargs; i++)
argv[i] = pack (cif->arg_types[i], args[i], 0);
result = scm_call_n (proc, argv, cif->nargs);
unpack (cif->rtype, ret, result, 1);
}
SCM_DEFINE (scm_procedure_to_pointer, "procedure->pointer", 3, 0, 0,
(SCM return_type, SCM proc, SCM arg_types),
"Return a pointer to a C function of type @var{return_type}\n"
"taking arguments of types @var{arg_types} (a list) and\n"
"behaving as a proxy to procedure @var{proc}. Thus\n"
"@var{proc}'s arity, supported argument types, and return\n"
"type should match @var{return_type} and @var{arg_types}.\n")
#define FUNC_NAME s_scm_procedure_to_pointer
{
SCM cif_pointer, pointer;
ffi_cif *cif;
ffi_status err;
void *closure, *executable;
cif = make_cif (return_type, arg_types, FUNC_NAME);
closure = ffi_closure_alloc (sizeof (ffi_closure), &executable);
err = ffi_prep_closure_loc ((ffi_closure *) closure, cif,
invoke_closure, SCM_UNPACK_POINTER (proc),
executable);
if (err != FFI_OK)
{
ffi_closure_free (closure);
SCM_MISC_ERROR ("`ffi_prep_closure_loc' failed", SCM_EOL);
}
/* CIF points to GC-managed memory and it should remain as long as
POINTER (see below) is live. Wrap it in a Scheme pointer to then
hold a weak reference on it. */
cif_pointer = scm_from_pointer (cif, NULL);
if (closure == executable)
{
pointer = scm_from_pointer (executable, ffi_closure_free);
register_weak_reference (pointer,
scm_list_2 (proc, cif_pointer));
}
else
{
/* CLOSURE needs to be freed eventually. However, since
`GC_all_interior_pointers' is disabled, we can't just register
a finalizer for CLOSURE. Instead, we create a pointer object
for CLOSURE, with a finalizer, and register it as a weak
reference of POINTER. */
SCM friend;
pointer = scm_from_pointer (executable, NULL);
friend = scm_from_pointer (closure, ffi_closure_free);
register_weak_reference (pointer,
scm_list_3 (proc, cif_pointer, friend));
}
return pointer;
}
#undef FUNC_NAME
#endif /* FFI_CLOSURES */
static void
scm_init_foreign (void)
{
#ifndef SCM_MAGIC_SNARFER
#include "foreign.x"
#endif
scm_define (sym_void, scm_from_uint8 (SCM_FOREIGN_TYPE_VOID));
scm_define (sym_float, scm_from_uint8 (SCM_FOREIGN_TYPE_FLOAT));
scm_define (sym_double, scm_from_uint8 (SCM_FOREIGN_TYPE_DOUBLE));
scm_define (sym_complex_float, scm_from_uint8 (SCM_FOREIGN_TYPE_COMPLEX_FLOAT));
scm_define (sym_complex_double, scm_from_uint8 (SCM_FOREIGN_TYPE_COMPLEX_DOUBLE));
scm_define (sym_uint8, scm_from_uint8 (SCM_FOREIGN_TYPE_UINT8));
scm_define (sym_int8, scm_from_uint8 (SCM_FOREIGN_TYPE_INT8));
scm_define (sym_uint16, scm_from_uint8 (SCM_FOREIGN_TYPE_UINT16));
scm_define (sym_int16, scm_from_uint8 (SCM_FOREIGN_TYPE_INT16));
scm_define (sym_uint32, scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32));
scm_define (sym_int32, scm_from_uint8 (SCM_FOREIGN_TYPE_INT32));
scm_define (sym_uint64, scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64));
scm_define (sym_int64, scm_from_uint8 (SCM_FOREIGN_TYPE_INT64));
scm_define (sym_short,
#if SIZEOF_SHORT == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SIZEOF_SHORT == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#elif SIZEOF_SHORT == 2
scm_from_uint8 (SCM_FOREIGN_TYPE_INT16)
#else
# error unsupported sizeof (short)
#endif
);
scm_define (sym_unsigned_short,
#if SIZEOF_SHORT == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64)
#elif SIZEOF_SHORT == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32)
#elif SIZEOF_SHORT == 2
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT16)
#else
# error unsupported sizeof (short)
#endif
);
scm_define (sym_int,
#if SIZEOF_INT == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SIZEOF_INT == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#else
# error unsupported sizeof (int)
#endif
);
scm_define (sym_unsigned_int,
#if SIZEOF_UNSIGNED_INT == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64)
#elif SIZEOF_UNSIGNED_INT == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32)
#else
# error unsupported sizeof (unsigned int)
#endif
);
scm_define (sym_long,
#if SIZEOF_LONG == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SIZEOF_LONG == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#else
# error unsupported sizeof (long)
#endif
);
scm_define (sym_unsigned_long,
#if SIZEOF_UNSIGNED_LONG == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64)
#elif SIZEOF_UNSIGNED_LONG == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32)
#else
# error unsupported sizeof (unsigned long)
#endif
);
scm_define (sym_size_t,
#if SIZEOF_SIZE_T == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64)
#elif SIZEOF_SIZE_T == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32)
#else
# error unsupported sizeof (size_t)
#endif
);
scm_define (sym_ssize_t,
#if SIZEOF_SIZE_T == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SIZEOF_SIZE_T == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#else
# error unsupported sizeof (ssize_t)
#endif
);
scm_define (sym_ptrdiff_t,
#if SCM_SIZEOF_SCM_T_PTRDIFF == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SCM_SIZEOF_SCM_T_PTRDIFF == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#else
# error unsupported sizeof (ptrdiff_t)
#endif
);
scm_define (sym_intptr_t,
#if SCM_SIZEOF_INTPTR_T == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_INT64)
#elif SCM_SIZEOF_INTPTR_T == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_INT32)
#else
# error unsupported sizeof (intptr_t)
#endif
);
scm_define (sym_uintptr_t,
#if SCM_SIZEOF_UINTPTR_T == 8
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT64)
#elif SCM_SIZEOF_UINTPTR_T == 4
scm_from_uint8 (SCM_FOREIGN_TYPE_UINT32)
#else
# error unsupported sizeof (uintptr_t)
#endif
);
null_pointer = scm_cell (scm_tc7_pointer, 0);
scm_define (sym_null, null_pointer);
}
void
scm_register_foreign (void)
{
scm_c_register_extension ("libguile-" SCM_EFFECTIVE_VERSION,
"scm_init_foreign",
(scm_t_extension_init_func)scm_init_foreign,
NULL);
pointer_weak_refs = scm_c_make_weak_table (0, SCM_WEAK_TABLE_KIND_KEY);
}
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