circuitpython/py/objgenerator.c

116 lines
3.6 KiB
C

#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <assert.h>
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "mpqstr.h"
#include "obj.h"
#include "runtime.h"
#include "bc.h"
/******************************************************************************/
/* generator wrapper */
typedef struct _mp_obj_gen_wrap_t {
mp_obj_base_t base;
uint n_state;
mp_obj_t *fun;
} mp_obj_gen_wrap_t;
// args are in reverse order in the array
mp_obj_t gen_wrap_call_n(mp_obj_t self_in, int n_args, const mp_obj_t *args) {
mp_obj_gen_wrap_t *self = self_in;
mp_obj_t self_fun = self->fun;
assert(MP_OBJ_IS_TYPE(self_fun, &fun_bc_type));
int bc_n_args;
uint bc_n_state;
const byte *bc_code;
mp_obj_fun_bc_get(self_fun, &bc_n_args, &bc_n_state, &bc_code);
if (n_args != bc_n_args) {
nlr_jump(mp_obj_new_exception_msg_2_args(MP_QSTR_TypeError, "function takes %d positional arguments but %d were given", (const char*)(machine_int_t)bc_n_args, (const char*)(machine_int_t)n_args));
}
return mp_obj_new_gen_instance(bc_code, self->n_state, n_args, args);
}
const mp_obj_type_t gen_wrap_type = {
{ &mp_const_type },
"generator",
.call_n = gen_wrap_call_n,
};
mp_obj_t mp_obj_new_gen_wrap(uint n_locals, uint n_stack, mp_obj_t fun) {
mp_obj_gen_wrap_t *o = m_new_obj(mp_obj_gen_wrap_t);
o->base.type = &gen_wrap_type;
// we have at least 3 locals so the bc can write back fast[0,1,2] safely; should improve how this is done
o->n_state = (n_locals < 3 ? 3 : n_locals) + n_stack;
o->fun = fun;
return o;
}
/******************************************************************************/
/* generator instance */
typedef struct _mp_obj_gen_instance_t {
mp_obj_base_t base;
const byte *ip;
mp_obj_t *sp;
mp_obj_t state[];
} mp_obj_gen_instance_t;
void gen_instance_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in) {
print(env, "<generator object 'fun-name' at %p>", self_in);
}
mp_obj_t gen_instance_getiter(mp_obj_t self_in) {
return self_in;
}
mp_obj_t gen_instance_iternext(mp_obj_t self_in) {
mp_obj_gen_instance_t *self = self_in;
bool yield = mp_execute_byte_code_2(&self->ip, &self->state[0], &self->sp);
if (yield) {
return *self->sp;
} else {
if (*self->sp == mp_const_none) {
return mp_const_stop_iteration;
} else {
// TODO return StopIteration with value *self->sp
return mp_const_stop_iteration;
}
}
}
const mp_obj_type_t gen_instance_type = {
{ &mp_const_type },
"generator",
.print = gen_instance_print,
.getiter = gen_instance_getiter,
.iternext = gen_instance_iternext,
};
// args are in reverse order in the array
mp_obj_t mp_obj_new_gen_instance(const byte *bytecode, uint n_state, int n_args, const mp_obj_t *args) {
mp_obj_gen_instance_t *o = m_new_obj_var(mp_obj_gen_instance_t, mp_obj_t, n_state);
o->base.type = &gen_instance_type;
o->ip = bytecode;
o->sp = o->state + n_state;
// copy args (which are in reverse order) to start of state array
for (int i = 0; i < n_args; i++) {
o->state[i] = args[n_args - 1 - i];
}
// TODO
// prelude for making cells (closed over variables)
// for now we just make sure there are no cells variables
// need to work out how to implement closed over variables in generators
assert(o->ip[0] == 0);
o->ip += 1;
return o;
}