1 /*
2  * This file is part of the MicroPython project, http://micropython.org/
3  *
4  * The MIT License (MIT)
5  *
6  * Copyright (c) 2013, 2014 Damien P. George
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 
27 #include <string.h>
28 
29 #include "py/obj.h"
30 #include "py/runtime.h"
31 
32 typedef struct _mp_obj_closure_t {
33     mp_obj_base_t base;
34     mp_obj_t fun;
35     size_t n_closed;
36     mp_obj_t closed[];
37 } mp_obj_closure_t;
38 
closure_call(mp_obj_t self_in,size_t n_args,size_t n_kw,const mp_obj_t * args)39 STATIC mp_obj_t closure_call(mp_obj_t self_in, size_t n_args, size_t n_kw, const mp_obj_t *args) {
40     mp_obj_closure_t *self = MP_OBJ_TO_PTR(self_in);
41 
42     // need to concatenate closed-over-vars and args
43 
44     size_t n_total = self->n_closed + n_args + 2 * n_kw;
45     if (n_total <= 5) {
46         // use stack to allocate temporary args array
47         mp_obj_t args2[5];
48         memcpy(args2, self->closed, self->n_closed * sizeof(mp_obj_t));
49         memcpy(args2 + self->n_closed, args, (n_args + 2 * n_kw) * sizeof(mp_obj_t));
50         return mp_call_function_n_kw(self->fun, self->n_closed + n_args, n_kw, args2);
51     } else {
52         // use heap to allocate temporary args array
53         mp_obj_t *args2 = m_new(mp_obj_t, n_total);
54         memcpy(args2, self->closed, self->n_closed * sizeof(mp_obj_t));
55         memcpy(args2 + self->n_closed, args, (n_args + 2 * n_kw) * sizeof(mp_obj_t));
56         mp_obj_t res = mp_call_function_n_kw(self->fun, self->n_closed + n_args, n_kw, args2);
57         m_del(mp_obj_t, args2, n_total);
58         return res;
59     }
60 }
61 
62 #if MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_DETAILED
closure_print(const mp_print_t * print,mp_obj_t o_in,mp_print_kind_t kind)63 STATIC void closure_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
64     (void)kind;
65     mp_obj_closure_t *o = MP_OBJ_TO_PTR(o_in);
66     mp_print_str(print, "<closure ");
67     mp_obj_print_helper(print, o->fun, PRINT_REPR);
68     mp_printf(print, " at %p, n_closed=%u ", o, (int)o->n_closed);
69     for (size_t i = 0; i < o->n_closed; i++) {
70         if (o->closed[i] == MP_OBJ_NULL) {
71             mp_print_str(print, "(nil)");
72         } else {
73             mp_obj_print_helper(print, o->closed[i], PRINT_REPR);
74         }
75         mp_print_str(print, " ");
76     }
77     mp_print_str(print, ">");
78 }
79 #endif
80 
81 const mp_obj_type_t mp_type_closure = {
82     { &mp_type_type },
83     .flags = MP_TYPE_FLAG_BINDS_SELF,
84     .name = MP_QSTR_closure,
85     #if MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_DETAILED
86     .print = closure_print,
87     #endif
88     .call = closure_call,
89 };
90 
mp_obj_new_closure(mp_obj_t fun,size_t n_closed_over,const mp_obj_t * closed)91 mp_obj_t mp_obj_new_closure(mp_obj_t fun, size_t n_closed_over, const mp_obj_t *closed) {
92     mp_obj_closure_t *o = m_new_obj_var(mp_obj_closure_t, mp_obj_t, n_closed_over);
93     o->base.type = &mp_type_closure;
94     o->fun = fun;
95     o->n_closed = n_closed_over;
96     memcpy(o->closed, closed, n_closed_over * sizeof(mp_obj_t));
97     return MP_OBJ_FROM_PTR(o);
98 }
99