1 /*
2  * This file is part of the MicroPython project, http://micropython.org/
3  *
4  * The MIT License (MIT)
5  *
6  * Copyright (c) 2014 Damien P. George
7  * Copyright (c) 2015-2017 Paul Sokolovsky
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  */
27 
28 #include "py/mpconfig.h"
29 #if MICROPY_PY_USELECT
30 
31 #include <stdio.h>
32 
33 #include "py/runtime.h"
34 #include "py/obj.h"
35 #include "py/objlist.h"
36 #include "py/stream.h"
37 #include "py/mperrno.h"
38 #include "py/mphal.h"
39 
40 // Flags for poll()
41 #define FLAG_ONESHOT (1)
42 
43 typedef struct _poll_obj_t {
44     mp_obj_t obj;
45     mp_uint_t (*ioctl)(mp_obj_t obj, mp_uint_t request, uintptr_t arg, int *errcode);
46     mp_uint_t flags;
47     mp_uint_t flags_ret;
48 } poll_obj_t;
49 
poll_map_add(mp_map_t * poll_map,const mp_obj_t * obj,mp_uint_t obj_len,mp_uint_t flags,bool or_flags)50 STATIC void poll_map_add(mp_map_t *poll_map, const mp_obj_t *obj, mp_uint_t obj_len, mp_uint_t flags, bool or_flags) {
51     for (mp_uint_t i = 0; i < obj_len; i++) {
52         mp_map_elem_t *elem = mp_map_lookup(poll_map, mp_obj_id(obj[i]), MP_MAP_LOOKUP_ADD_IF_NOT_FOUND);
53         if (elem->value == MP_OBJ_NULL) {
54             // object not found; get its ioctl and add it to the poll list
55             const mp_stream_p_t *stream_p = mp_get_stream_raise(obj[i], MP_STREAM_OP_IOCTL);
56             poll_obj_t *poll_obj = m_new_obj(poll_obj_t);
57             poll_obj->obj = obj[i];
58             poll_obj->ioctl = stream_p->ioctl;
59             poll_obj->flags = flags;
60             poll_obj->flags_ret = 0;
61             elem->value = MP_OBJ_FROM_PTR(poll_obj);
62         } else {
63             // object exists; update its flags
64             if (or_flags) {
65                 ((poll_obj_t *)MP_OBJ_TO_PTR(elem->value))->flags |= flags;
66             } else {
67                 ((poll_obj_t *)MP_OBJ_TO_PTR(elem->value))->flags = flags;
68             }
69         }
70     }
71 }
72 
73 // poll each object in the map
poll_map_poll(mp_map_t * poll_map,size_t * rwx_num)74 STATIC mp_uint_t poll_map_poll(mp_map_t *poll_map, size_t *rwx_num) {
75     mp_uint_t n_ready = 0;
76     for (mp_uint_t i = 0; i < poll_map->alloc; ++i) {
77         if (!mp_map_slot_is_filled(poll_map, i)) {
78             continue;
79         }
80 
81         poll_obj_t *poll_obj = MP_OBJ_TO_PTR(poll_map->table[i].value);
82         int errcode;
83         mp_int_t ret = poll_obj->ioctl(poll_obj->obj, MP_STREAM_POLL, poll_obj->flags, &errcode);
84         poll_obj->flags_ret = ret;
85 
86         if (ret == -1) {
87             // error doing ioctl
88             mp_raise_OSError(errcode);
89         }
90 
91         if (ret != 0) {
92             // object is ready
93             n_ready += 1;
94             if (rwx_num != NULL) {
95                 if (ret & MP_STREAM_POLL_RD) {
96                     rwx_num[0] += 1;
97                 }
98                 if (ret & MP_STREAM_POLL_WR) {
99                     rwx_num[1] += 1;
100                 }
101                 if ((ret & ~(MP_STREAM_POLL_RD | MP_STREAM_POLL_WR)) != 0) {
102                     rwx_num[2] += 1;
103                 }
104             }
105         }
106     }
107     return n_ready;
108 }
109 
110 #if MICROPY_PY_USELECT_SELECT
111 // select(rlist, wlist, xlist[, timeout])
select_select(size_t n_args,const mp_obj_t * args)112 STATIC mp_obj_t select_select(size_t n_args, const mp_obj_t *args) {
113     // get array data from tuple/list arguments
114     size_t rwx_len[3];
115     mp_obj_t *r_array, *w_array, *x_array;
116     mp_obj_get_array(args[0], &rwx_len[0], &r_array);
117     mp_obj_get_array(args[1], &rwx_len[1], &w_array);
118     mp_obj_get_array(args[2], &rwx_len[2], &x_array);
119 
120     // get timeout
121     mp_uint_t timeout = -1;
122     if (n_args == 4) {
123         if (args[3] != mp_const_none) {
124             #if MICROPY_PY_BUILTINS_FLOAT
125             float timeout_f = mp_obj_get_float_to_f(args[3]);
126             if (timeout_f >= 0) {
127                 timeout = (mp_uint_t)(timeout_f * 1000);
128             }
129             #else
130             timeout = mp_obj_get_int(args[3]) * 1000;
131             #endif
132         }
133     }
134 
135     // merge separate lists and get the ioctl function for each object
136     mp_map_t poll_map;
137     mp_map_init(&poll_map, rwx_len[0] + rwx_len[1] + rwx_len[2]);
138     poll_map_add(&poll_map, r_array, rwx_len[0], MP_STREAM_POLL_RD, true);
139     poll_map_add(&poll_map, w_array, rwx_len[1], MP_STREAM_POLL_WR, true);
140     poll_map_add(&poll_map, x_array, rwx_len[2], MP_STREAM_POLL_ERR | MP_STREAM_POLL_HUP, true);
141 
142     mp_uint_t start_tick = mp_hal_ticks_ms();
143     rwx_len[0] = rwx_len[1] = rwx_len[2] = 0;
144     for (;;) {
145         // poll the objects
146         mp_uint_t n_ready = poll_map_poll(&poll_map, rwx_len);
147 
148         if (n_ready > 0 || (timeout != (mp_uint_t)-1 && mp_hal_ticks_ms() - start_tick >= timeout)) {
149             // one or more objects are ready, or we had a timeout
150             mp_obj_t list_array[3];
151             list_array[0] = mp_obj_new_list(rwx_len[0], NULL);
152             list_array[1] = mp_obj_new_list(rwx_len[1], NULL);
153             list_array[2] = mp_obj_new_list(rwx_len[2], NULL);
154             rwx_len[0] = rwx_len[1] = rwx_len[2] = 0;
155             for (mp_uint_t i = 0; i < poll_map.alloc; ++i) {
156                 if (!mp_map_slot_is_filled(&poll_map, i)) {
157                     continue;
158                 }
159                 poll_obj_t *poll_obj = MP_OBJ_TO_PTR(poll_map.table[i].value);
160                 if (poll_obj->flags_ret & MP_STREAM_POLL_RD) {
161                     ((mp_obj_list_t *)MP_OBJ_TO_PTR(list_array[0]))->items[rwx_len[0]++] = poll_obj->obj;
162                 }
163                 if (poll_obj->flags_ret & MP_STREAM_POLL_WR) {
164                     ((mp_obj_list_t *)MP_OBJ_TO_PTR(list_array[1]))->items[rwx_len[1]++] = poll_obj->obj;
165                 }
166                 if ((poll_obj->flags_ret & ~(MP_STREAM_POLL_RD | MP_STREAM_POLL_WR)) != 0) {
167                     ((mp_obj_list_t *)MP_OBJ_TO_PTR(list_array[2]))->items[rwx_len[2]++] = poll_obj->obj;
168                 }
169             }
170             mp_map_deinit(&poll_map);
171             return mp_obj_new_tuple(3, list_array);
172         }
173         MICROPY_EVENT_POLL_HOOK
174     }
175 }
176 MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_select_select_obj, 3, 4, select_select);
177 #endif // MICROPY_PY_USELECT_SELECT
178 
179 typedef struct _mp_obj_poll_t {
180     mp_obj_base_t base;
181     mp_map_t poll_map;
182     short iter_cnt;
183     short iter_idx;
184     int flags;
185     // callee-owned tuple
186     mp_obj_t ret_tuple;
187 } mp_obj_poll_t;
188 
189 // register(obj[, eventmask])
poll_register(size_t n_args,const mp_obj_t * args)190 STATIC mp_obj_t poll_register(size_t n_args, const mp_obj_t *args) {
191     mp_obj_poll_t *self = MP_OBJ_TO_PTR(args[0]);
192     mp_uint_t flags;
193     if (n_args == 3) {
194         flags = mp_obj_get_int(args[2]);
195     } else {
196         flags = MP_STREAM_POLL_RD | MP_STREAM_POLL_WR;
197     }
198     poll_map_add(&self->poll_map, &args[1], 1, flags, false);
199     return mp_const_none;
200 }
201 MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_register_obj, 2, 3, poll_register);
202 
203 // unregister(obj)
poll_unregister(mp_obj_t self_in,mp_obj_t obj_in)204 STATIC mp_obj_t poll_unregister(mp_obj_t self_in, mp_obj_t obj_in) {
205     mp_obj_poll_t *self = MP_OBJ_TO_PTR(self_in);
206     mp_map_lookup(&self->poll_map, mp_obj_id(obj_in), MP_MAP_LOOKUP_REMOVE_IF_FOUND);
207     // TODO raise KeyError if obj didn't exist in map
208     return mp_const_none;
209 }
210 MP_DEFINE_CONST_FUN_OBJ_2(poll_unregister_obj, poll_unregister);
211 
212 // modify(obj, eventmask)
poll_modify(mp_obj_t self_in,mp_obj_t obj_in,mp_obj_t eventmask_in)213 STATIC mp_obj_t poll_modify(mp_obj_t self_in, mp_obj_t obj_in, mp_obj_t eventmask_in) {
214     mp_obj_poll_t *self = MP_OBJ_TO_PTR(self_in);
215     mp_map_elem_t *elem = mp_map_lookup(&self->poll_map, mp_obj_id(obj_in), MP_MAP_LOOKUP);
216     if (elem == NULL) {
217         mp_raise_OSError(MP_ENOENT);
218     }
219     ((poll_obj_t *)MP_OBJ_TO_PTR(elem->value))->flags = mp_obj_get_int(eventmask_in);
220     return mp_const_none;
221 }
222 MP_DEFINE_CONST_FUN_OBJ_3(poll_modify_obj, poll_modify);
223 
poll_poll_internal(uint n_args,const mp_obj_t * args)224 STATIC mp_uint_t poll_poll_internal(uint n_args, const mp_obj_t *args) {
225     mp_obj_poll_t *self = MP_OBJ_TO_PTR(args[0]);
226 
227     // work out timeout (its given already in ms)
228     mp_uint_t timeout = -1;
229     int flags = 0;
230     if (n_args >= 2) {
231         if (args[1] != mp_const_none) {
232             mp_int_t timeout_i = mp_obj_get_int(args[1]);
233             if (timeout_i >= 0) {
234                 timeout = timeout_i;
235             }
236         }
237         if (n_args >= 3) {
238             flags = mp_obj_get_int(args[2]);
239         }
240     }
241 
242     self->flags = flags;
243 
244     mp_uint_t start_tick = mp_hal_ticks_ms();
245     mp_uint_t n_ready;
246     for (;;) {
247         // poll the objects
248         n_ready = poll_map_poll(&self->poll_map, NULL);
249         if (n_ready > 0 || (timeout != (mp_uint_t)-1 && mp_hal_ticks_ms() - start_tick >= timeout)) {
250             break;
251         }
252         MICROPY_EVENT_POLL_HOOK
253     }
254 
255     return n_ready;
256 }
257 
poll_poll(size_t n_args,const mp_obj_t * args)258 STATIC mp_obj_t poll_poll(size_t n_args, const mp_obj_t *args) {
259     mp_obj_poll_t *self = MP_OBJ_TO_PTR(args[0]);
260     mp_uint_t n_ready = poll_poll_internal(n_args, args);
261 
262     // one or more objects are ready, or we had a timeout
263     mp_obj_list_t *ret_list = MP_OBJ_TO_PTR(mp_obj_new_list(n_ready, NULL));
264     n_ready = 0;
265     for (mp_uint_t i = 0; i < self->poll_map.alloc; ++i) {
266         if (!mp_map_slot_is_filled(&self->poll_map, i)) {
267             continue;
268         }
269         poll_obj_t *poll_obj = MP_OBJ_TO_PTR(self->poll_map.table[i].value);
270         if (poll_obj->flags_ret != 0) {
271             mp_obj_t tuple[2] = {poll_obj->obj, MP_OBJ_NEW_SMALL_INT(poll_obj->flags_ret)};
272             ret_list->items[n_ready++] = mp_obj_new_tuple(2, tuple);
273             if (self->flags & FLAG_ONESHOT) {
274                 // Don't poll next time, until new event flags will be set explicitly
275                 poll_obj->flags = 0;
276             }
277         }
278     }
279     return MP_OBJ_FROM_PTR(ret_list);
280 }
281 MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_poll_obj, 1, 3, poll_poll);
282 
poll_ipoll(size_t n_args,const mp_obj_t * args)283 STATIC mp_obj_t poll_ipoll(size_t n_args, const mp_obj_t *args) {
284     mp_obj_poll_t *self = MP_OBJ_TO_PTR(args[0]);
285 
286     if (self->ret_tuple == MP_OBJ_NULL) {
287         self->ret_tuple = mp_obj_new_tuple(2, NULL);
288     }
289 
290     int n_ready = poll_poll_internal(n_args, args);
291     self->iter_cnt = n_ready;
292     self->iter_idx = 0;
293 
294     return args[0];
295 }
296 MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(poll_ipoll_obj, 1, 3, poll_ipoll);
297 
poll_iternext(mp_obj_t self_in)298 STATIC mp_obj_t poll_iternext(mp_obj_t self_in) {
299     mp_obj_poll_t *self = MP_OBJ_TO_PTR(self_in);
300 
301     if (self->iter_cnt == 0) {
302         return MP_OBJ_STOP_ITERATION;
303     }
304 
305     self->iter_cnt--;
306 
307     for (mp_uint_t i = self->iter_idx; i < self->poll_map.alloc; ++i) {
308         self->iter_idx++;
309         if (!mp_map_slot_is_filled(&self->poll_map, i)) {
310             continue;
311         }
312         poll_obj_t *poll_obj = MP_OBJ_TO_PTR(self->poll_map.table[i].value);
313         if (poll_obj->flags_ret != 0) {
314             mp_obj_tuple_t *t = MP_OBJ_TO_PTR(self->ret_tuple);
315             t->items[0] = poll_obj->obj;
316             t->items[1] = MP_OBJ_NEW_SMALL_INT(poll_obj->flags_ret);
317             if (self->flags & FLAG_ONESHOT) {
318                 // Don't poll next time, until new event flags will be set explicitly
319                 poll_obj->flags = 0;
320             }
321             return MP_OBJ_FROM_PTR(t);
322         }
323     }
324 
325     assert(!"inconsistent number of poll active entries");
326     self->iter_cnt = 0;
327     return MP_OBJ_STOP_ITERATION;
328 }
329 
330 STATIC const mp_rom_map_elem_t poll_locals_dict_table[] = {
331     { MP_ROM_QSTR(MP_QSTR_register), MP_ROM_PTR(&poll_register_obj) },
332     { MP_ROM_QSTR(MP_QSTR_unregister), MP_ROM_PTR(&poll_unregister_obj) },
333     { MP_ROM_QSTR(MP_QSTR_modify), MP_ROM_PTR(&poll_modify_obj) },
334     { MP_ROM_QSTR(MP_QSTR_poll), MP_ROM_PTR(&poll_poll_obj) },
335     { MP_ROM_QSTR(MP_QSTR_ipoll), MP_ROM_PTR(&poll_ipoll_obj) },
336 };
337 STATIC MP_DEFINE_CONST_DICT(poll_locals_dict, poll_locals_dict_table);
338 
339 STATIC const mp_obj_type_t mp_type_poll = {
340     { &mp_type_type },
341     .name = MP_QSTR_poll,
342     .getiter = mp_identity_getiter,
343     .iternext = poll_iternext,
344     .locals_dict = (void *)&poll_locals_dict,
345 };
346 
347 // poll()
select_poll(void)348 STATIC mp_obj_t select_poll(void) {
349     mp_obj_poll_t *poll = m_new_obj(mp_obj_poll_t);
350     poll->base.type = &mp_type_poll;
351     mp_map_init(&poll->poll_map, 0);
352     poll->iter_cnt = 0;
353     poll->ret_tuple = MP_OBJ_NULL;
354     return MP_OBJ_FROM_PTR(poll);
355 }
356 MP_DEFINE_CONST_FUN_OBJ_0(mp_select_poll_obj, select_poll);
357 
358 STATIC const mp_rom_map_elem_t mp_module_select_globals_table[] = {
359     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uselect) },
360     #if MICROPY_PY_USELECT_SELECT
361     { MP_ROM_QSTR(MP_QSTR_select), MP_ROM_PTR(&mp_select_select_obj) },
362     #endif
363     { MP_ROM_QSTR(MP_QSTR_poll), MP_ROM_PTR(&mp_select_poll_obj) },
364     { MP_ROM_QSTR(MP_QSTR_POLLIN), MP_ROM_INT(MP_STREAM_POLL_RD) },
365     { MP_ROM_QSTR(MP_QSTR_POLLOUT), MP_ROM_INT(MP_STREAM_POLL_WR) },
366     { MP_ROM_QSTR(MP_QSTR_POLLERR), MP_ROM_INT(MP_STREAM_POLL_ERR) },
367     { MP_ROM_QSTR(MP_QSTR_POLLHUP), MP_ROM_INT(MP_STREAM_POLL_HUP) },
368 };
369 
370 STATIC MP_DEFINE_CONST_DICT(mp_module_select_globals, mp_module_select_globals_table);
371 
372 const mp_obj_module_t mp_module_uselect = {
373     .base = { &mp_type_module },
374     .globals = (mp_obj_dict_t *)&mp_module_select_globals,
375 };
376 
377 #endif // MICROPY_PY_USELECT
378