Commit 4729a0cc authored by Damien George's avatar Damien George
Browse files

Merge pull request #235 from pfalcon/modffi

unix: Initial FFI module implementation
parents 7f11c794 809eaa26
import ffi
libc = ffi.open("libc.so.6")
print("libc:", libc)
print()
# Declare few functions
perror = libc.func("v", "perror", ["s"])
time = libc.func("i", "time", "p")
open = libc.func("i", "open", ["s", "i"])
qsort = libc.func("v", "qsort", "piip")
# And one variable
errno = libc.var("i", "errno")
print("time:", time)
print("UNIX time is:", time(None))
print()
perror("ffi before error")
open("somethingnonexistent__", 0)
print(errno)
perror("ffi after error")
print()
def cmp(pa, pb):
a = ffi.as_bytearray(pa, 1)
b = ffi.as_bytearray(pb, 1)
print("cmp:", a, b)
return a[0] - b[0]
cmp_c = ffi.callback("i", cmp, "pp")
print("callback:", cmp_c)
# TODO: violates Py semantics, pass bytearray
s = "foobar"
print("org string:", s)
qsort(s, len(s), 1, cmp_c)
print("qsort'ed:", s)
......@@ -11,7 +11,7 @@ include ../py/py.mk
# compiler settings
CFLAGS = -I. -I$(PY_SRC) -Wall -Werror -ansi -std=gnu99 -DUNIX
LDFLAGS = -lm
LDFLAGS = -lm -ldl -lffi
# Debugging/Optimization
ifdef DEBUG
......@@ -25,6 +25,7 @@ SRC_C = \
main.c \
file.c \
socket.c \
ffi.c \
OBJ = $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
LIB = -lreadline
......
#include <assert.h>
#include <string.h>
#include <errno.h>
#include <dlfcn.h>
#include <ffi.h>
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "obj.h"
#include "runtime.h"
typedef struct _mp_obj_opaque_t {
mp_obj_base_t base;
void *val;
} mp_obj_opaque_t;
typedef struct _mp_obj_ffimod_t {
mp_obj_base_t base;
void *handle;
} mp_obj_ffimod_t;
typedef struct _mp_obj_ffivar_t {
mp_obj_base_t base;
void *var;
char type;
// ffi_type *type;
} mp_obj_ffivar_t;
typedef struct _mp_obj_ffifunc_t {
mp_obj_base_t base;
void *func;
char rettype;
ffi_cif cif;
ffi_type *params[];
} mp_obj_ffifunc_t;
typedef struct _mp_obj_fficallback_t {
mp_obj_base_t base;
void *func;
ffi_closure *clo;
char rettype;
ffi_cif cif;
ffi_type *params[];
} mp_obj_fficallback_t;
static const mp_obj_type_t opaque_type;
static const mp_obj_type_t ffimod_type;
static const mp_obj_type_t ffifunc_type;
static const mp_obj_type_t fficallback_type;
static const mp_obj_type_t ffivar_type;
static ffi_type *char2ffi_type(char c)
{
switch (c) {
case 'b': return &ffi_type_schar;
case 'B': return &ffi_type_uchar;
case 'i': return &ffi_type_sint;
case 'I': return &ffi_type_uint;
case 'l': return &ffi_type_slong;
case 'L': return &ffi_type_ulong;
case 'p':
case 's': return &ffi_type_pointer;
case 'v': return &ffi_type_void;
default: return NULL;
}
}
static ffi_type *get_ffi_type(mp_obj_t o_in)
{
if (MP_OBJ_IS_STR(o_in)) {
uint len;
const byte *s = mp_obj_str_get_data(o_in, &len);
ffi_type *t = char2ffi_type(*s);
if (t != NULL) {
return t;
}
}
// TODO: Support actual libffi type objects
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "Unknown type"));
}
static mp_obj_t return_ffi_value(int val, char type)
{
switch (type) {
case 's': {
const char *s = (const char *)val;
return mp_obj_new_str((const byte *)s, strlen(s), false);
}
case 'v':
return mp_const_none;
default:
return mp_obj_new_int(val);
}
}
// FFI module
static void ffimod_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
mp_obj_ffimod_t *self = self_in;
print(env, "<ffimod %p>", self->handle);
}
static mp_obj_t ffimod_close(mp_obj_t self_in) {
mp_obj_ffimod_t *self = self_in;
dlclose(self->handle);
return mp_const_none;
}
static MP_DEFINE_CONST_FUN_OBJ_1(ffimod_close_obj, ffimod_close);
static mp_obj_t ffimod_func(uint n_args, const mp_obj_t *args) {
mp_obj_ffimod_t *self = args[0];
const char *rettype = mp_obj_str_get_str(args[1]);
const char *symname = mp_obj_str_get_str(args[2]);
void *sym = dlsym(self->handle, symname);
if (sym == NULL) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "[Errno %d]", errno));
}
int nparams = MP_OBJ_SMALL_INT_VALUE(mp_obj_len_maybe(args[3]));
mp_obj_ffifunc_t *o = m_new_obj_var(mp_obj_ffifunc_t, ffi_type*, nparams);
o->base.type = &ffifunc_type;
o->func = sym;
o->rettype = *rettype;
mp_obj_t iterable = rt_getiter(args[3]);
mp_obj_t item;
int i = 0;
while ((item = rt_iternext(iterable)) != mp_const_stop_iteration) {
o->params[i++] = get_ffi_type(item);
}
int res = ffi_prep_cif(&o->cif, FFI_DEFAULT_ABI, nparams, char2ffi_type(*rettype), o->params);
if (res != FFI_OK) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "Error in ffi_prep_cif"));
}
return o;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(ffimod_func_obj, 4, 4, ffimod_func);
static void call_py_func(ffi_cif *cif, void *ret, void** args, mp_obj_t func) {
mp_obj_t pyargs[cif->nargs];
for (int i = 0; i < cif->nargs; i++) {
pyargs[i] = mp_obj_new_int(*(int*)args[i]);
}
mp_obj_t res = rt_call_function_n_kw(func, cif->nargs, 0, pyargs);
*(ffi_arg*)ret = mp_obj_int_get(res);
}
static mp_obj_t mod_ffi_callback(mp_obj_t rettype_in, mp_obj_t func_in, mp_obj_t paramtypes_in) {
const char *rettype = mp_obj_str_get_str(rettype_in);
int nparams = MP_OBJ_SMALL_INT_VALUE(mp_obj_len_maybe(paramtypes_in));
mp_obj_fficallback_t *o = m_new_obj_var(mp_obj_fficallback_t, ffi_type*, nparams);
o->base.type = &fficallback_type;
o->clo = ffi_closure_alloc(sizeof(ffi_closure), &o->func);
o->rettype = *rettype;
mp_obj_t iterable = rt_getiter(paramtypes_in);
mp_obj_t item;
int i = 0;
while ((item = rt_iternext(iterable)) != mp_const_stop_iteration) {
o->params[i++] = get_ffi_type(item);
}
int res = ffi_prep_cif(&o->cif, FFI_DEFAULT_ABI, nparams, char2ffi_type(*rettype), o->params);
if (res != FFI_OK) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "Error in ffi_prep_cif"));
}
res = ffi_prep_closure_loc(o->clo, &o->cif, call_py_func, func_in, o->func);
if (res != FFI_OK) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "ffi_prep_closure_loc"));
}
return o;
}
MP_DEFINE_CONST_FUN_OBJ_3(mod_ffi_callback_obj, mod_ffi_callback);
static mp_obj_t ffimod_var(mp_obj_t self_in, mp_obj_t vartype_in, mp_obj_t symname_in) {
mp_obj_ffimod_t *self = self_in;
const char *rettype = mp_obj_str_get_str(vartype_in);
const char *symname = mp_obj_str_get_str(symname_in);
void *sym = dlsym(self->handle, symname);
if (sym == NULL) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "[Errno %d]", errno));
}
mp_obj_ffivar_t *o = m_new_obj(mp_obj_ffivar_t);
o->base.type = &ffivar_type;
o->var = sym;
o->type = *rettype;
return o;
}
MP_DEFINE_CONST_FUN_OBJ_3(ffimod_var_obj, ffimod_var);
static mp_obj_t ffimod_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
const char *fname = mp_obj_str_get_str(args[0]);
void *mod = dlopen(fname, RTLD_NOW | RTLD_LOCAL);
if (mod == NULL) {
nlr_jump(mp_obj_new_exception_msg_varg(MP_QSTR_OSError, "[Errno %d]", errno));
}
mp_obj_ffimod_t *o = m_new_obj(mp_obj_ffimod_t);
o->base.type = type_in;
o->handle = mod;
return o;
}
static const mp_method_t ffimod_type_methods[] = {
{ "func", &ffimod_func_obj },
{ "var", &ffimod_var_obj },
{ "close", &ffimod_close_obj },
{ NULL, NULL },
};
static const mp_obj_type_t ffimod_type = {
{ &mp_const_type },
"ffimod",
.print = ffimod_print,
.make_new = ffimod_make_new,
.methods = ffimod_type_methods,
};
// FFI function
static void ffifunc_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
mp_obj_ffifunc_t *self = self_in;
print(env, "<ffifunc %p>", self->func);
}
mp_obj_t ffifunc_call(mp_obj_t self_in, uint n_args, uint n_kw, const mp_obj_t *args) {
mp_obj_ffifunc_t *self = self_in;
assert(n_kw == 0);
assert(n_args == self->cif.nargs);
int values[n_args];
void *valueptrs[n_args];
int i;
for (i = 0; i < n_args; i++) {
mp_obj_t a = args[i];
if (a == mp_const_none) {
values[i] = 0;
} else if (MP_OBJ_IS_INT(a)) {
values[i] = mp_obj_int_get(a);
} else if (MP_OBJ_IS_STR(a) || MP_OBJ_IS_TYPE(a, &bytes_type)) {
const char *s = mp_obj_str_get_str(a);
values[i] = (int)s;
} else if (MP_OBJ_IS_TYPE(a, &fficallback_type)) {
mp_obj_fficallback_t *p = a;
values[i] = (int)p->func;
} else {
assert(0);
}
valueptrs[i] = &values[i];
}
int retval;
ffi_call(&self->cif, self->func, &retval, valueptrs);
return return_ffi_value(retval, self->rettype);
}
static const mp_obj_type_t ffifunc_type = {
{ &mp_const_type },
"ffifunc",
.print = ffifunc_print,
.call = ffifunc_call,
};
// FFI callback for Python function
static void fficallback_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
mp_obj_fficallback_t *self = self_in;
print(env, "<fficallback %p>", self->func);
}
static const mp_obj_type_t fficallback_type = {
{ &mp_const_type },
"fficallback",
.print = fficallback_print,
};
// FFI variable
static void ffivar_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
mp_obj_ffivar_t *self = self_in;
print(env, "<ffivar @%p: 0x%x>", self->var, *(int*)self->var);
}
static const mp_obj_type_t ffivar_type = {
{ &mp_const_type },
"ffivar",
.print = ffivar_print,
};
// Generic opaque storage object
static const mp_obj_type_t opaque_type = {
{ &mp_const_type },
"opaqueval",
// .print = opaque_print,
};
mp_obj_t mod_ffi_open(uint n_args, const mp_obj_t *args) {
return ffimod_make_new((mp_obj_t)&ffimod_type, n_args, 0, args);
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_ffi_open_obj, 1, 2, mod_ffi_open);
mp_obj_t mod_ffi_as_bytearray(mp_obj_t ptr, mp_obj_t size) {
return mp_obj_new_bytearray_by_ref(mp_obj_int_get(size), (void*)mp_obj_int_get(ptr));
}
MP_DEFINE_CONST_FUN_OBJ_2(mod_ffi_as_bytearray_obj, mod_ffi_as_bytearray);
void ffi_init() {
mp_obj_t m = mp_obj_new_module(QSTR_FROM_STR_STATIC("ffi"));
rt_store_attr(m, MP_QSTR_open, (mp_obj_t)&mod_ffi_open_obj);
rt_store_attr(m, QSTR_FROM_STR_STATIC("callback"), (mp_obj_t)&mod_ffi_callback_obj);
// there would be as_bytes, but bytes currently is value, not reference type!
rt_store_attr(m, QSTR_FROM_STR_STATIC("as_bytearray"), (mp_obj_t)&mod_ffi_as_bytearray_obj);
}
......@@ -24,6 +24,7 @@
extern const mp_obj_fun_native_t mp_builtin_open_obj;
void file_init();
void rawsocket_init();
void ffi_init();
static void execute_from_lexer(mp_lexer_t *lex, mp_parse_input_kind_t input_kind, bool is_repl) {
if (lex == NULL) {
......@@ -227,6 +228,7 @@ int main(int argc, char **argv) {
file_init();
rawsocket_init();
ffi_init();
// Here is some example code to create a class and instance of that class.
// First is the Python, then the C code.
......
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