X-Git-Url: https://git.hcoop.net/bpt/guile.git/blobdiff_plain/087aa6aa312a8d0af51fa9b2f7bfc1332ad97338..9866cfe48489919f4527adba94ce2b5f74895e41:/libguile/foreign.c diff --git a/libguile/foreign.c b/libguile/foreign.c index c87c378a7..1e91661ad 100644 --- a/libguile/foreign.c +++ b/libguile/foreign.c @@ -1,5 +1,5 @@ /* Copyright (C) 2010 Free Software Foundation, Inc. - * + * * This library 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 @@ -24,6 +24,8 @@ #include #include +#include + #include "libguile/_scm.h" #include "libguile/bytevectors.h" #include "libguile/instructions.h" @@ -42,191 +44,150 @@ SCM_SYMBOL (sym_uint32, "uint32"); SCM_SYMBOL (sym_int32, "int32"); SCM_SYMBOL (sym_uint64, "uint64"); SCM_SYMBOL (sym_int64, "int64"); +SCM_SYMBOL (sym_int, "int"); +SCM_SYMBOL (sym_long, "long"); +SCM_SYMBOL (sym_unsigned_int, "unsigned-int"); +SCM_SYMBOL (sym_unsigned_long, "unsigned-long"); +SCM_SYMBOL (sym_size_t, "size_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; + +#if SIZEOF_VOID_P == 4 +# define scm_to_uintptr scm_to_uint32 +# define scm_from_uintptr scm_from_uint32 +#elif SIZEOF_VOID_P == 8 +# define scm_to_uintptr scm_to_uint64 +# define scm_from_uintptr scm_from_uint64 +#else +# error unsupported pointer size +#endif + + +/* 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); -static SCM foreign_weak_refs = SCM_BOOL_F; +static SCM pointer_weak_refs = SCM_BOOL_F; static void register_weak_reference (SCM from, SCM to) { - scm_hashq_set_x (foreign_weak_refs, from, to); + scm_hashq_set_x (pointer_weak_refs, from, to); } - + static void -foreign_finalizer_trampoline (GC_PTR ptr, GC_PTR data) +pointer_finalizer_trampoline (GC_PTR ptr, GC_PTR data) { - scm_t_foreign_finalizer finalizer = data; - finalizer (SCM_FOREIGN_POINTER (PTR2SCM (ptr), void)); + scm_t_pointer_finalizer finalizer = data; + finalizer (SCM_POINTER_VALUE (PTR2SCM (ptr))); } -SCM -scm_take_foreign_pointer (scm_t_foreign_type type, void *ptr, size_t len, - scm_t_foreign_finalizer finalizer) +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 { - SCM ret; - scm_t_bits word0; - - word0 = (scm_t_bits)(scm_tc7_foreign | (type<<8) - | (finalizer ? (1<<16) : 0) | (len<<17)); - if (SCM_UNLIKELY ((word0 >> 17) != len)) - scm_out_of_range ("scm_take_foreign_pointer", scm_from_size_t (len)); - - ret = PTR2SCM (scm_gc_malloc_pointerless (sizeof (scm_t_bits) * 2, - "foreign")); - SCM_SET_CELL_WORD_0 (ret, word0); - SCM_SET_CELL_WORD_1 (ret, (scm_t_bits)ptr); + void *c_finalizer; + scm_t_uintptr c_address; - if (finalizer) + c_address = scm_to_uintptr (address); + if (SCM_UNBNDP (finalizer)) + c_finalizer = NULL; + else { - /* Register a finalizer for the newly created instance. */ - GC_finalization_proc prev_finalizer; - GC_PTR prev_finalizer_data; - GC_REGISTER_FINALIZER_NO_ORDER (SCM2PTR (ret), - foreign_finalizer_trampoline, - finalizer, - &prev_finalizer, - &prev_finalizer_data); + SCM_VALIDATE_POINTER (2, finalizer); + c_finalizer = SCM_POINTER_VALUE (finalizer); } - return ret; + return scm_from_pointer ((void *) c_address, c_finalizer); } +#undef FUNC_NAME -SCM_DEFINE (scm_foreign_ref, "foreign-ref", 1, 0, 0, - (SCM foreign), - "Reference the foreign value wrapped by @var{foreign}.\n\n" - "The value will be referenced according to its type.") -#define FUNC_NAME s_scm_foreign_ref +SCM +scm_from_pointer (void *ptr, scm_t_pointer_finalizer finalizer) { - scm_t_foreign_type ftype; - scm_t_uint8 *ptr; + SCM ret; - SCM_VALIDATE_FOREIGN (1, foreign); - ptr = SCM_FOREIGN_POINTER (foreign, scm_t_uint8); - ftype = SCM_FOREIGN_TYPE (foreign); - - /* FIXME: is there a window in which we can see ptr but not foreign? */ - /* FIXME: accessing unaligned pointers */ - switch (ftype) + if (ptr == NULL && finalizer == NULL) + ret = null_pointer; + else { - case SCM_FOREIGN_TYPE_VOID: - return scm_from_ulong ((unsigned long)ptr); - case SCM_FOREIGN_TYPE_FLOAT: - return scm_from_double (*(float*)ptr); - case SCM_FOREIGN_TYPE_DOUBLE: - return scm_from_double (*(double*)ptr); - case SCM_FOREIGN_TYPE_UINT8: - return scm_from_uint8 (*(scm_t_uint8*)ptr); - case SCM_FOREIGN_TYPE_INT8: - return scm_from_int8 (*(scm_t_int8*)ptr); - case SCM_FOREIGN_TYPE_UINT16: - return scm_from_uint16 (*(scm_t_uint16*)ptr); - case SCM_FOREIGN_TYPE_INT16: - return scm_from_int16 (*(scm_t_int16*)ptr); - case SCM_FOREIGN_TYPE_UINT32: - return scm_from_uint32 (*(scm_t_uint32*)ptr); - case SCM_FOREIGN_TYPE_INT32: - return scm_from_int32 (*(scm_t_int32*)ptr); - case SCM_FOREIGN_TYPE_UINT64: - return scm_from_uint64 (*(scm_t_uint64*)ptr); - case SCM_FOREIGN_TYPE_INT64: - return scm_from_int64 (*(scm_t_int64*)ptr); - default: - scm_wrong_type_arg_msg (FUNC_NAME, 1, foreign, "foreign"); + scm_t_bits type; + + type = scm_tc7_pointer | (finalizer ? (1 << 16UL) : 0UL); + ret = scm_cell (type, (scm_t_bits) ptr); + + if (finalizer) + { + /* Register a finalizer for the newly created instance. */ + GC_finalization_proc prev_finalizer; + GC_PTR prev_finalizer_data; + GC_REGISTER_FINALIZER_NO_ORDER (SCM2PTR (ret), + pointer_finalizer_trampoline, + finalizer, + &prev_finalizer, + &prev_finalizer_data); + } } + + return ret; } -#undef FUNC_NAME -SCM_DEFINE (scm_foreign_set_x, "foreign-set!", 2, 0, 0, - (SCM foreign, SCM val), - "Set the foreign value wrapped by @var{foreign}.\n\n" - "The value will be set according to its type.") -#define FUNC_NAME s_scm_foreign_set_x +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_t_foreign_type ftype; - scm_t_uint8 *ptr; - - SCM_VALIDATE_FOREIGN (1, foreign); - ptr = SCM_FOREIGN_POINTER (foreign, scm_t_uint8); - ftype = SCM_FOREIGN_TYPE (foreign); + SCM_VALIDATE_POINTER (1, pointer); - /* FIXME: is there a window in which we can see ptr but not foreign? */ - /* FIXME: unaligned access */ - switch (ftype) - { - case SCM_FOREIGN_TYPE_VOID: - SCM_SET_CELL_WORD_1 (foreign, scm_to_ulong (val)); - break; - case SCM_FOREIGN_TYPE_FLOAT: - *(float*)ptr = scm_to_double (val); - break; - case SCM_FOREIGN_TYPE_DOUBLE: - *(double*)ptr = scm_to_double (val); - break; - case SCM_FOREIGN_TYPE_UINT8: - *(scm_t_uint8*)ptr = scm_to_uint8 (val); - break; - case SCM_FOREIGN_TYPE_INT8: - *(scm_t_int8*)ptr = scm_to_int8 (val); - break; - case SCM_FOREIGN_TYPE_UINT16: - *(scm_t_uint16*)ptr = scm_to_uint16 (val); - break; - case SCM_FOREIGN_TYPE_INT16: - *(scm_t_int16*)ptr = scm_to_int16 (val); - break; - case SCM_FOREIGN_TYPE_UINT32: - *(scm_t_uint32*)ptr = scm_to_uint32 (val); - break; - case SCM_FOREIGN_TYPE_INT32: - *(scm_t_int32*)ptr = scm_to_int32 (val); - break; - case SCM_FOREIGN_TYPE_UINT64: - *(scm_t_uint64*)ptr = scm_to_uint64 (val); - break; - case SCM_FOREIGN_TYPE_INT64: - *(scm_t_int64*)ptr = scm_to_int64 (val); - break; - default: - scm_wrong_type_arg_msg (FUNC_NAME, 1, val, "foreign"); - } - - return SCM_UNSPECIFIED; + return scm_from_uintptr ((scm_t_uintptr) SCM_POINTER_VALUE (pointer)); } #undef FUNC_NAME -SCM_DEFINE (scm_foreign_to_bytevector, "foreign->bytevector", 1, 3, 0, - (SCM foreign, SCM uvec_type, SCM offset, SCM len), - "Return a bytevector aliasing the memory pointed to by\n" - "@var{foreign}.\n\n" - "@var{foreign} must be a void pointer, a foreign whose type is\n" - "@var{void}. By default, the resulting bytevector will alias\n" - "all of the memory pointed to by @var{foreign}, from beginning\n" - "to end, treated as a @code{vu8} array.\n\n" +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" - "Users may also specify that the bytevector should only alias a\n" - "subset of the memory, by specifying @var{offset} and @var{len}\n" - "arguments.") -#define FUNC_NAME s_scm_foreign_to_bytevector + "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; scm_t_int8 *ptr; size_t boffset, blen; scm_t_array_element_type btype; - SCM_VALIDATE_FOREIGN_TYPED (1, foreign, VOID); - ptr = SCM_FOREIGN_POINTER (foreign, scm_t_int8); - + 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 @@ -257,98 +218,67 @@ SCM_DEFINE (scm_foreign_to_bytevector, "foreign->bytevector", 1, 3, 0, "uniform vector type"); } } - + if (SCM_UNBNDP (offset)) boffset = 0; - else if (SCM_FOREIGN_LEN (foreign)) - boffset = scm_to_unsigned_integer (offset, 0, - SCM_FOREIGN_LEN (foreign) - 1); else boffset = scm_to_size_t (offset); - if (SCM_UNBNDP (len)) - { - if (SCM_FOREIGN_LEN (foreign)) - blen = SCM_FOREIGN_LEN (foreign) - boffset; - else - scm_misc_error (FUNC_NAME, - "length needed to convert foreign pointer to bytevector", - SCM_EOL); - } - else - { - if (SCM_FOREIGN_LEN (foreign)) - blen = scm_to_unsigned_integer (len, 0, - SCM_FOREIGN_LEN (foreign) - boffset); - else - blen = scm_to_size_t (len); - } + blen = scm_to_size_t (len); ret = scm_c_take_typed_bytevector (ptr + boffset, blen, btype); - register_weak_reference (ret, foreign); + register_weak_reference (ret, pointer); return ret; } #undef FUNC_NAME -SCM_DEFINE (scm_bytevector_to_foreign, "bytevector->foreign", 1, 2, 0, - (SCM bv, SCM offset, SCM len), - "Return a foreign pointer aliasing the memory pointed to by\n" - "@var{bv}.\n\n" - "The resulting foreign will be a void pointer, a foreign whose\n" - "type is @code{void}. By default it will alias all of the\n" - "memory pointed to by @var{bv}, from beginning to end.\n\n" - "Users may explicily specify that the foreign should only alias a\n" - "subset of the memory, by specifying @var{offset} and @var{len}\n" - "arguments.") -#define FUNC_NAME s_scm_bytevector_to_foreign +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; scm_t_int8 *ptr; - size_t boffset, blen; + 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); - if (SCM_UNBNDP (len)) - blen = SCM_BYTEVECTOR_LENGTH (bv) - boffset; - else - blen = scm_to_unsigned_integer (len, 0, - SCM_BYTEVECTOR_LENGTH (bv) - boffset); - - ret = scm_take_foreign_pointer (SCM_FOREIGN_TYPE_VOID, ptr + boffset, blen, - NULL); + ret = scm_from_pointer (ptr + boffset, NULL); register_weak_reference (ret, bv); return ret; } #undef FUNC_NAME -SCM_DEFINE (scm_foreign_set_finalizer_x, "foreign-set-finalizer!", 2, 0, 0, - (SCM foreign, SCM finalizer), +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{foreign} when @var{foreign}\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_foreign_set_finalizer_x +#define FUNC_NAME s_scm_set_pointer_finalizer_x { void *c_finalizer; GC_finalization_proc prev_finalizer; GC_PTR prev_finalizer_data; - SCM_VALIDATE_FOREIGN_TYPED (1, foreign, VOID); - SCM_VALIDATE_FOREIGN_TYPED (2, finalizer, VOID); - - c_finalizer = SCM_FOREIGN_POINTER (finalizer, void); + SCM_VALIDATE_POINTER (1, pointer); + SCM_VALIDATE_POINTER (2, finalizer); + + c_finalizer = SCM_POINTER_VALUE (finalizer); - SCM_SET_CELL_WORD_0 (foreign, SCM_CELL_WORD_0 (foreign) | (1<<16)); + SCM_SET_CELL_WORD_0 (pointer, SCM_CELL_WORD_0 (pointer) | (1 << 16UL)); - GC_REGISTER_FINALIZER_NO_ORDER (SCM2PTR (foreign), - foreign_finalizer_trampoline, + GC_REGISTER_FINALIZER_NO_ORDER (SCM2PTR (pointer), + pointer_finalizer_trampoline, c_finalizer, &prev_finalizer, &prev_finalizer_data); @@ -357,60 +287,72 @@ SCM_DEFINE (scm_foreign_set_finalizer_x, "foreign-set-finalizer!", 2, 0, 0, } #undef FUNC_NAME - - void -scm_i_foreign_print (SCM foreign, SCM port, scm_print_state *pstate) +scm_i_pointer_print (SCM pointer, SCM port, scm_print_state *pstate) { - scm_puts ("#', 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 +{ + SCM_VALIDATE_POINTER (1, pointer); + return scm_from_pointer (* (void **) SCM_POINTER_VALUE (pointer), NULL); +} +#undef FUNC_NAME -#define ROUND_UP(len,align) (align?(((len-1)|(align-1))+1):len) +SCM_DEFINE (scm_string_to_pointer, "string->pointer", 1, 0, 0, + (SCM string), + "Return a foreign pointer to a nul-terminated copy of\n" + "@var{string} in the current locale encoding. The C\n" + "string is freed when the returned foreign pointer\n" + "becomes unreachable.\n\n" + "This is the Scheme equivalent of @code{scm_to_locale_string}.") +#define FUNC_NAME s_scm_string_to_pointer +{ + SCM_VALIDATE_STRING (1, string); -SCM_DEFINE (scm_alignof, "alignof", 1, 0, 0, (SCM type), "") + /* XXX: Finalizers slow down libgc; they could be avoided if + `scm_to_string' & co. were able to use libgc-allocated memory. */ + + return scm_from_pointer (scm_to_locale_string (string), free); +} +#undef FUNC_NAME + +SCM_DEFINE (scm_pointer_to_string, "pointer->string", 1, 0, 0, + (SCM pointer), + "Return the string representing the C nul-terminated string\n" + "pointed to by @var{pointer}. The C string is assumed to be\n" + "in the current locale encoding.\n\n" + "This is the Scheme equivalent of @code{scm_from_locale_string}.") +#define FUNC_NAME s_scm_pointer_to_string +{ + SCM_VALIDATE_POINTER (1, pointer); + + return scm_from_locale_string (SCM_POINTER_VALUE (pointer)); +} +#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)) @@ -452,7 +394,13 @@ SCM_DEFINE (scm_alignof, "alignof", 1, 0, 0, (SCM type), "") } #undef FUNC_NAME -SCM_DEFINE (scm_sizeof, "sizeof", 1, 0, 0, (SCM type), "") +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)) @@ -582,7 +530,7 @@ fill_ffi_type (SCM type, ffi_type *ftype, ffi_type ***type_ptrs, *ftype = ffi_type_void; return; default: - scm_wrong_type_arg_msg ("make-foreign-function", 0, type, + scm_wrong_type_arg_msg ("pointer->procedure", 0, type, "foreign type"); } } @@ -615,21 +563,21 @@ fill_ffi_type (SCM type, ffi_type *ftype, ffi_type ***type_ptrs, ftype->elements[i] = NULL; } } - -SCM_DEFINE (scm_make_foreign_function, "make-foreign-function", 3, 0, 0, - (SCM return_type, SCM func_ptr, SCM arg_types), - "foo") -#define FUNC_NAME s_scm_make_foreign_function + +/* 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, scm_cif; + 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; - - SCM_VALIDATE_FOREIGN_TYPED (2, func_ptr, VOID); + nargs = scm_ilength (arg_types); SCM_ASSERT (nargs >= 0, arg_types, 3, FUNC_NAME); /* fixme: assert nargs < 1<<32 */ @@ -643,33 +591,31 @@ SCM_DEFINE (scm_make_foreign_function, "make-foreign-function", 3, 0, 0, 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(void*)) - + (nargs + n_structs + n_struct_elts)*sizeof(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(ffi_type)) - + (nargs + n_struct_elts + 1)*sizeof(ffi_type)); + + (nargs + n_struct_elts + 1)*sizeof(ffi_type)); mem = scm_gc_malloc_pointerless (cif_len, "foreign"); - scm_cif = scm_take_foreign_pointer (SCM_FOREIGN_TYPE_VOID, mem, - cif_len, NULL); cif = (ffi_cif *) mem; /* reuse cif_len to walk through the mem */ cif_len = ROUND_UP (sizeof (ffi_cif), alignof(void*)); type_ptrs = (ffi_type**)(mem + cif_len); cif_len = ROUND_UP (cif_len - + (nargs + n_structs + n_struct_elts)*sizeof(void*), - alignof(ffi_type)); + + (nargs + n_structs + n_struct_elts)*sizeof(void*), + alignof(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); @@ -686,12 +632,33 @@ SCM_DEFINE (scm_make_foreign_function, "make-foreign-function", 3, 0, 0, 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 (FUNC_NAME, "ffi_prep_cif failed", SCM_EOL); + cif->arg_types)) + SCM_MISC_ERROR ("ffi_prep_cif failed", SCM_EOL); - return cif_to_procedure (scm_cif, func_ptr); + return cif; +} +#undef FUNC_NAME + +SCM_DEFINE (scm_pointer_to_procedure, "pointer->procedure", 3, 0, 0, + (SCM return_type, SCM func_ptr, SCM arg_types), + "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.") +#define FUNC_NAME s_scm_pointer_to_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); } #undef FUNC_NAME @@ -811,9 +778,13 @@ static const SCM objcode_trampolines[10] = { static SCM cif_to_procedure (SCM cif, SCM func_ptr) { - unsigned nargs = SCM_FOREIGN_POINTER (cif, ffi_cif)->nargs; + ffi_cif *c_cif; + unsigned int nargs; SCM objcode, table, ret; - + + c_cif = (ffi_cif *) SCM_POINTER_VALUE (cif); + nargs = c_cif->nargs; + if (nargs < 10) objcode = objcode_trampolines[nargs]; else @@ -828,136 +799,144 @@ cif_to_procedure (SCM cif, SCM func_ptr) return ret; } +/* Set *LOC to the foreign representation of X with TYPE. */ static void -unpack (ffi_type *type, void *loc, SCM x) +unpack (const ffi_type *type, void *loc, SCM x) { switch (type->type) { case FFI_TYPE_FLOAT: - *(float*)loc = scm_to_double (x); + *(float *) loc = scm_to_double (x); break; case FFI_TYPE_DOUBLE: - *(double*)loc = scm_to_double (x); + *(double *) loc = scm_to_double (x); break; case FFI_TYPE_UINT8: - *(scm_t_uint8*)loc = scm_to_uint8 (x); + *(scm_t_uint8 *) loc = scm_to_uint8 (x); break; case FFI_TYPE_SINT8: - *(scm_t_int8*)loc = scm_to_int8 (x); + *(scm_t_int8 *) loc = scm_to_int8 (x); break; case FFI_TYPE_UINT16: - *(scm_t_uint16*)loc = scm_to_uint16 (x); + *(scm_t_uint16 *) loc = scm_to_uint16 (x); break; case FFI_TYPE_SINT16: - *(scm_t_int16*)loc = scm_to_int16 (x); + *(scm_t_int16 *) loc = scm_to_int16 (x); break; case FFI_TYPE_UINT32: - *(scm_t_uint32*)loc = scm_to_uint32 (x); + *(scm_t_uint32 *) loc = scm_to_uint32 (x); break; case FFI_TYPE_SINT32: - *(scm_t_int32*)loc = scm_to_int32 (x); + *(scm_t_int32 *) loc = scm_to_int32 (x); break; case FFI_TYPE_UINT64: - *(scm_t_uint64*)loc = scm_to_uint64 (x); + *(scm_t_uint64 *) loc = scm_to_uint64 (x); break; case FFI_TYPE_SINT64: - *(scm_t_int64*)loc = scm_to_int64 (x); + *(scm_t_int64 *) loc = scm_to_int64 (x); break; case FFI_TYPE_STRUCT: - if (!SCM_FOREIGN_TYPED_P (x, VOID)) - scm_wrong_type_arg_msg ("foreign-call", 0, x, - "foreign void pointer"); - if (SCM_FOREIGN_LEN (x) && SCM_FOREIGN_LEN (x) != type->size) - scm_wrong_type_arg_msg ("foreign-call", 0, x, - "foreign void pointer of correct length"); - memcpy (loc, SCM_FOREIGN_POINTER (x, void), type->size); + memcpy (loc, SCM_POINTER_VALUE (x), type->size); break; case FFI_TYPE_POINTER: - if (!SCM_FOREIGN_TYPED_P (x, VOID)) - scm_wrong_type_arg_msg ("foreign-call", 0, x, - "foreign void pointer"); - *(void**)loc = SCM_FOREIGN_POINTER (x, void); + *(void **) loc = SCM_POINTER_VALUE (x); break; default: abort (); } } +/* Return a Scheme representation of the foreign value at LOC of type TYPE. */ static SCM -pack (ffi_type *type, void *loc) +pack (const ffi_type * type, const void *loc) { switch (type->type) { case FFI_TYPE_VOID: return SCM_UNSPECIFIED; case FFI_TYPE_FLOAT: - return scm_from_double (*(float*)loc); + return scm_from_double (*(float *) loc); case FFI_TYPE_DOUBLE: - return scm_from_double (*(double*)loc); + return scm_from_double (*(double *) loc); case FFI_TYPE_UINT8: - return scm_from_uint8 (*(scm_t_uint8*)loc); + return scm_from_uint8 (*(scm_t_uint8 *) loc); case FFI_TYPE_SINT8: - return scm_from_int8 (*(scm_t_int8*)loc); + return scm_from_int8 (*(scm_t_int8 *) loc); case FFI_TYPE_UINT16: - return scm_from_uint16 (*(scm_t_uint16*)loc); + return scm_from_uint16 (*(scm_t_uint16 *) loc); case FFI_TYPE_SINT16: - return scm_from_int16 (*(scm_t_int16*)loc); + return scm_from_int16 (*(scm_t_int16 *) loc); case FFI_TYPE_UINT32: - return scm_from_uint32 (*(scm_t_uint32*)loc); + return scm_from_uint32 (*(scm_t_uint32 *) loc); case FFI_TYPE_SINT32: - return scm_from_int32 (*(scm_t_int32*)loc); + return scm_from_int32 (*(scm_t_int32 *) loc); case FFI_TYPE_UINT64: - return scm_from_uint64 (*(scm_t_uint64*)loc); + return scm_from_uint64 (*(scm_t_uint64 *) loc); case FFI_TYPE_SINT64: - return scm_from_int64 (*(scm_t_int64*)loc); + return scm_from_int64 (*(scm_t_int64 *) loc); case FFI_TYPE_STRUCT: { - void *mem = scm_gc_malloc_pointerless (type->size, "foreign"); - memcpy (mem, loc, type->size); - return scm_take_foreign_pointer (SCM_FOREIGN_TYPE_VOID, - mem, type->size, NULL); + 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_take_foreign_pointer (SCM_FOREIGN_TYPE_VOID, - *(void**)loc, 0, NULL); + return scm_from_pointer (*(void **) loc, NULL); default: abort (); } } + SCM -scm_i_foreign_call (SCM foreign, SCM *argv) +scm_i_foreign_call (SCM foreign, const SCM *argv) { /* FOREIGN is the pair that cif_to_procedure set as the 0th element of the objtable. */ ffi_cif *cif; - void (*func)(); + void (*func) (void); scm_t_uint8 *data; void *rvalue; void **args; unsigned i; + size_t arg_size; scm_t_ptrdiff off; - cif = SCM_FOREIGN_POINTER (scm_car (foreign), ffi_cif); - func = SCM_FOREIGN_POINTER (scm_cdr (foreign), void); - - /* arg pointers */ - args = alloca (sizeof(void*) * cif->nargs); - /* arg values, then return type value */ - data = alloca (ROUND_UP (cif->bytes, cif->rtype->alignment) - + cif->rtype->size); - /* unpack argv to native values, setting argv pointers */ - off = 0; - for (i = 0; i < cif->nargs; i++) + cif = SCM_POINTER_VALUE (SCM_CAR (foreign)); + func = SCM_POINTER_VALUE (SCM_CDR (foreign)); + + /* 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 = (scm_t_uint8 *) args[i] - data + cif->arg_types[i]->size, + i++) { - off = ROUND_UP (off, cif->arg_types[i]->alignment); - args[i] = data + off; + /* Suitably align the storage area for argument I. */ + args[i] = (void *) ROUND_UP ((scm_t_uintptr) data + off, + cif->arg_types[i]->alignment); + assert ((scm_t_uintptr) args[i] % cif->arg_types[i]->alignment == 0); unpack (cif->arg_types[i], args[i], argv[i]); - off += cif->arg_types[i]->size; } - /* prep space for the return value */ - off = ROUND_UP (off, cif->rtype->alignment); - rvalue = data + off; + + /* 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 ((scm_t_uintptr) data + off, + max (sizeof (void *), cif->rtype->alignment)); /* off we go! */ ffi_call (cif, func, rvalue, args); @@ -966,6 +945,81 @@ scm_i_foreign_call (SCM foreign, SCM *argv) } +/* 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 = PTR2SCM (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]); + + result = scm_call_n (proc, argv, cif->nargs); + + unpack (cif->rtype, ret, result); +} + +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 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, SCM2PTR (proc), + executable); + if (err != FFI_OK) + { + ffi_closure_free (closure); + SCM_MISC_ERROR ("`ffi_prep_closure_loc' failed", SCM_EOL); + } + + if (closure == executable) + pointer = scm_from_pointer (executable, ffi_closure_free); + 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, friend); + } + + return pointer; +} +#undef FUNC_NAME + +#endif /* FFI_CLOSURES */ + + static void scm_init_foreign (void) @@ -984,6 +1038,59 @@ scm_init_foreign (void) 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_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 + ); + + null_pointer = scm_cell (scm_tc7_pointer, 0); + scm_define (sym_null, null_pointer); } void @@ -993,7 +1100,7 @@ scm_register_foreign (void) "scm_init_foreign", (scm_t_extension_init_func)scm_init_foreign, NULL); - foreign_weak_refs = scm_make_weak_key_hash_table (SCM_UNDEFINED); + pointer_weak_refs = scm_make_weak_key_hash_table (SCM_UNDEFINED); } /*