CircuitPython

Source code browser

Note: This site will be taken down by the end of the year

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
/*
 * This file is part of the Micro Python project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013, 2014 Damien P. George
 * Copyright (c) 2014 Paul Sokolovsky
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "py/nlr.h"
#include "py/compile.h"
#include "py/objmodule.h"
#include "py/persistentcode.h"
#include "py/runtime.h"
#include "py/builtin.h"
#include "py/frozenmod.h"

#if 0 // print debugging info
#define DEBUG_PRINT (1)
#define DEBUG_printf DEBUG_printf
#else // don't print debugging info
#define DEBUG_PRINT (0)
#define DEBUG_printf(...) (void)0
#endif

#define PATH_SEP_CHAR '/'

#if MICROPY_MODULE_WEAK_LINKS
STATIC const mp_rom_map_elem_t mp_builtin_module_weak_links_table[] = {
    MICROPY_PORT_BUILTIN_MODULE_WEAK_LINKS
};

STATIC MP_DEFINE_CONST_MAP(mp_builtin_module_weak_links_map, mp_builtin_module_weak_links_table);
#endif

bool mp_obj_is_package(mp_obj_t module) {
    mp_obj_t dest[2];
    mp_load_method_maybe(module, MP_QSTR___path__, dest);
    return dest[0] != MP_OBJ_NULL;
}

// Stat either frozen or normal module by a given path
// (whatever is available, if at all).
STATIC mp_import_stat_t mp_import_stat_any(const char *path) {
    #if MICROPY_MODULE_FROZEN
    mp_import_stat_t st = mp_frozen_stat(path);
    if (st != MP_IMPORT_STAT_NO_EXIST) {
        return st;
    }
    #endif
    return mp_import_stat(path);
}

STATIC mp_import_stat_t stat_file_py_or_mpy(vstr_t *path) {
    mp_import_stat_t stat = mp_import_stat_any(vstr_null_terminated_str(path));
    if (stat == MP_IMPORT_STAT_FILE) {
        return stat;
    }

    #if MICROPY_PERSISTENT_CODE_LOAD
    vstr_ins_byte(path, path->len - 2, 'm');
    stat = mp_import_stat_any(vstr_null_terminated_str(path));
    if (stat == MP_IMPORT_STAT_FILE) {
        return stat;
    }
    #endif

    return MP_IMPORT_STAT_NO_EXIST;
}

STATIC mp_import_stat_t stat_dir_or_file(vstr_t *path) {
    mp_import_stat_t stat = mp_import_stat_any(vstr_null_terminated_str(path));
    DEBUG_printf("stat %s: %d\n", vstr_str(path), stat);
    if (stat == MP_IMPORT_STAT_DIR) {
        return stat;
    }

    // not a directory, add .py and try as a file
    vstr_add_str(path, ".py");
    return stat_file_py_or_mpy(path);
}

STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *dest) {
#if MICROPY_PY_SYS
    // extract the list of paths
    mp_uint_t path_num;
    mp_obj_t *path_items;
    mp_obj_list_get(mp_sys_path, &path_num, &path_items);

    if (path_num == 0) {
#endif
        // mp_sys_path is empty, so just use the given file name
        vstr_add_strn(dest, file_str, file_len);
        return stat_dir_or_file(dest);
#if MICROPY_PY_SYS
    } else {
        // go through each path looking for a directory or file
        for (mp_uint_t i = 0; i < path_num; i++) {
            vstr_reset(dest);
            mp_uint_t p_len;
            const char *p = mp_obj_str_get_data(path_items[i], &p_len);
            if (p_len > 0) {
                vstr_add_strn(dest, p, p_len);
                vstr_add_char(dest, PATH_SEP_CHAR);
            }
            vstr_add_strn(dest, file_str, file_len);
            mp_import_stat_t stat = stat_dir_or_file(dest);
            if (stat != MP_IMPORT_STAT_NO_EXIST) {
                return stat;
            }
        }

        // could not find a directory or file
        return MP_IMPORT_STAT_NO_EXIST;
    }
#endif
}

#if MICROPY_ENABLE_COMPILER
STATIC void do_load_from_lexer(mp_obj_t module_obj, mp_lexer_t *lex, const char *fname) {

    if (lex == NULL) {
        // we verified the file exists using stat, but lexer could still fail
        if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
            mp_raise_msg(&mp_type_ImportError, "module not found");
        } else {
            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ImportError,
                "no module named '%s'", fname));
        }
    }

    #if MICROPY_PY___FILE__
    qstr source_name = lex->source_name;
    mp_store_attr(module_obj, MP_QSTR___file__, MP_OBJ_NEW_QSTR(source_name));
    #endif

    // parse, compile and execute the module in its context
    mp_obj_dict_t *mod_globals = mp_obj_module_get_globals(module_obj);
    mp_parse_compile_execute(lex, MP_PARSE_FILE_INPUT, mod_globals, mod_globals);
}
#endif

#if MICROPY_PERSISTENT_CODE_LOAD || MICROPY_MODULE_FROZEN_MPY
STATIC void do_execute_raw_code(mp_obj_t module_obj, mp_raw_code_t *raw_code) {
    #if MICROPY_PY___FILE__
    // TODO
    //qstr source_name = lex->source_name;
    //mp_store_attr(module_obj, MP_QSTR___file__, MP_OBJ_NEW_QSTR(source_name));
    #endif

    // execute the module in its context
    mp_obj_dict_t *mod_globals = mp_obj_module_get_globals(module_obj);

    // save context
    mp_obj_dict_t *volatile old_globals = mp_globals_get();
    mp_obj_dict_t *volatile old_locals = mp_locals_get();

    // set new context
    mp_globals_set(mod_globals);
    mp_locals_set(mod_globals);

    nlr_buf_t nlr;
    if (nlr_push(&nlr) == 0) {
        mp_obj_t module_fun = mp_make_function_from_raw_code(raw_code, MP_OBJ_NULL, MP_OBJ_NULL);
        mp_call_function_0(module_fun);

        // finish nlr block, restore context
        nlr_pop();
        mp_globals_set(old_globals);
        mp_locals_set(old_locals);
    } else {
        // exception; restore context and re-raise same exception
        mp_globals_set(old_globals);
        mp_locals_set(old_locals);
        nlr_jump(nlr.ret_val);
    }
}
#endif

STATIC void do_load(mp_obj_t module_obj, vstr_t *file) {
    #if MICROPY_MODULE_FROZEN || MICROPY_PERSISTENT_CODE_LOAD || MICROPY_ENABLE_COMPILER
    char *file_str = vstr_null_terminated_str(file);
    #endif

    // If we support frozen modules (either as str or mpy) then try to find the
    // requested filename in the list of frozen module filenames.
    #if MICROPY_MODULE_FROZEN
    void *modref;
    int frozen_type = mp_find_frozen_module(file_str, file->len, &modref);
    #endif

    // If we support frozen str modules and the compiler is enabled, and we
    // found the filename in the list of frozen files, then load and execute it.
    #if MICROPY_MODULE_FROZEN_STR
    if (frozen_type == MP_FROZEN_STR) {
        do_load_from_lexer(module_obj, modref, file_str);
        return;
    }
    #endif

    // If we support frozen mpy modules and we found a corresponding file (and
    // its data) in the list of frozen files, execute it.
    #if MICROPY_MODULE_FROZEN_MPY
    if (frozen_type == MP_FROZEN_MPY) {
        do_execute_raw_code(module_obj, modref);
        return;
    }
    #endif

    // If we support loading .mpy files then check if the file extension is of
    // the correct format and, if so, load and execute the file.
    #if MICROPY_PERSISTENT_CODE_LOAD
    if (file_str[file->len - 3] == 'm') {
        mp_raw_code_t *raw_code = mp_raw_code_load_file(file_str);
        do_execute_raw_code(module_obj, raw_code);
        return;
    }
    #endif

    // If we can compile scripts then load the file and compile and execute it.
    #if MICROPY_ENABLE_COMPILER
    {
        mp_lexer_t *lex = mp_lexer_new_from_file(file_str);
        do_load_from_lexer(module_obj, lex, file_str);
        return;
    }
    #endif

    // If we get here then the file was not frozen and we can't compile scripts.
    nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ImportError,
        "script compilation not supported"));
}

STATIC void chop_component(const char *start, const char **end) {
    const char *p = *end;
    while (p > start) {
        if (*--p == '.') {
            *end = p;
            return;
        }
    }
    *end = p;
}

mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) {
#if DEBUG_PRINT
    DEBUG_printf("__import__:\n");
    for (mp_uint_t i = 0; i < n_args; i++) {
        DEBUG_printf("  ");
        mp_obj_print(args[i], PRINT_REPR);
        DEBUG_printf("\n");
    }
#endif

    mp_obj_t module_name = args[0];
    mp_obj_t fromtuple = mp_const_none;
    mp_int_t level = 0;
    if (n_args >= 4) {
        fromtuple = args[3];
        if (n_args >= 5) {
            level = MP_OBJ_SMALL_INT_VALUE(args[4]);
        }
    }

    mp_uint_t mod_len;
    const char *mod_str = mp_obj_str_get_data(module_name, &mod_len);

    if (level != 0) {
        // What we want to do here is to take name of current module,
        // chop <level> trailing components, and concatenate with passed-in
        // module name, thus resolving relative import name into absolue.
        // This even appears to be correct per
        // http://legacy.python.org/dev/peps/pep-0328/#relative-imports-and-name
        // "Relative imports use a module's __name__ attribute to determine that
        // module's position in the package hierarchy."
        level--;
        mp_obj_t this_name_q = mp_obj_dict_get(MP_OBJ_FROM_PTR(mp_globals_get()), MP_OBJ_NEW_QSTR(MP_QSTR___name__));
        assert(this_name_q != MP_OBJ_NULL);
        #if MICROPY_CPYTHON_COMPAT
        if (MP_OBJ_QSTR_VALUE(this_name_q) == MP_QSTR___main__) {
            // This is a module run by -m command-line switch, get its real name from backup attribute
            this_name_q = mp_obj_dict_get(MP_OBJ_FROM_PTR(mp_globals_get()), MP_OBJ_NEW_QSTR(MP_QSTR___main__));
        }
        #endif
        mp_map_t *globals_map = &mp_globals_get()->map;
        mp_map_elem_t *elem = mp_map_lookup(globals_map, MP_OBJ_NEW_QSTR(MP_QSTR___path__), MP_MAP_LOOKUP);
        bool is_pkg = (elem != NULL);

#if DEBUG_PRINT
        DEBUG_printf("Current module/package: ");
        mp_obj_print(this_name_q, PRINT_REPR);
        DEBUG_printf(", is_package: %d", is_pkg);
        DEBUG_printf("\n");
#endif

        mp_uint_t this_name_l;
        const char *this_name = mp_obj_str_get_data(this_name_q, &this_name_l);

        const char *p = this_name + this_name_l;
        if (!is_pkg) {
            // We have module, but relative imports are anchored at package, so
            // go there.
            chop_component(this_name, &p);
        }


        uint dots_seen = 0;
        while (level--) {
            chop_component(this_name, &p);
            dots_seen++;
        }

        if (dots_seen == 0 && level >= 1) {
            // http://legacy.python.org/dev/peps/pep-0328/#relative-imports-and-name
            // "If the module's name does not contain any package information
            // (e.g. it is set to '__main__') then relative imports are
            // resolved as if the module were a top level module, regardless
            // of where the module is actually located on the file system."
            // Supposedly this if catches this condition and resolve it properly
            // TODO: But nobody knows for sure. This condition happens when
            // package's __init__.py does something like "import .submod". So,
            // maybe we should check for package here? But quote above doesn't
            // talk about packages, it talks about dot-less module names.
            DEBUG_printf("Warning: no dots in current module name and level>0\n");
            p = this_name + this_name_l;
        } else if (level != -1) {
            mp_raise_msg(&mp_type_ImportError, "invalid relative import");
        }

        uint new_mod_l = (mod_len == 0 ? (size_t)(p - this_name) : (size_t)(p - this_name) + 1 + mod_len);
        char *new_mod = alloca(new_mod_l);
        memcpy(new_mod, this_name, p - this_name);
        if (mod_len != 0) {
            new_mod[p - this_name] = '.';
            memcpy(new_mod + (p - this_name) + 1, mod_str, mod_len);
        }

        qstr new_mod_q = qstr_from_strn(new_mod, new_mod_l);
        DEBUG_printf("Resolved base name for relative import: '%s'\n", qstr_str(new_mod_q));
        if (new_mod_q == MP_QSTR_) {
            // CPython raises SystemError
            mp_raise_msg(&mp_type_ImportError, "cannot perform relative import");
        }
        module_name = MP_OBJ_NEW_QSTR(new_mod_q);
        mod_str = new_mod;
        mod_len = new_mod_l;
    }

    // check if module already exists
    qstr module_name_qstr = mp_obj_str_get_qstr(module_name);
    mp_obj_t module_obj = mp_module_get(module_name_qstr);
    if (module_obj != MP_OBJ_NULL) {
        DEBUG_printf("Module already loaded\n");
        // If it's not a package, return module right away
        char *p = strchr(mod_str, '.');
        if (p == NULL) {
            return module_obj;
        }
        // If fromlist is not empty, return leaf module
        if (fromtuple != mp_const_none) {
            return module_obj;
        }
        // Otherwise, we need to return top-level package
        qstr pkg_name = qstr_from_strn(mod_str, p - mod_str);
        return mp_module_get(pkg_name);
    }
    DEBUG_printf("Module not yet loaded\n");

    uint last = 0;
    VSTR_FIXED(path, MICROPY_ALLOC_PATH_MAX)
    module_obj = MP_OBJ_NULL;
    mp_obj_t top_module_obj = MP_OBJ_NULL;
    mp_obj_t outer_module_obj = MP_OBJ_NULL;
    uint i;
    for (i = 1; i <= mod_len; i++) {
        if (i == mod_len || mod_str[i] == '.') {
            // create a qstr for the module name up to this depth
            qstr mod_name = qstr_from_strn(mod_str, i);
            DEBUG_printf("Processing module: %s\n", qstr_str(mod_name));
            DEBUG_printf("Previous path: =%.*s=\n", vstr_len(&path), vstr_str(&path));

            // find the file corresponding to the module name
            mp_import_stat_t stat;
            if (vstr_len(&path) == 0) {
                // first module in the dotted-name; search for a directory or file
                stat = find_file(mod_str, i, &path);
            } else {
                // latter module in the dotted-name; append to path
                vstr_add_char(&path, PATH_SEP_CHAR);
                vstr_add_strn(&path, mod_str + last, i - last);
                stat = stat_dir_or_file(&path);
            }
            DEBUG_printf("Current path: %.*s\n", vstr_len(&path), vstr_str(&path));

            if (stat == MP_IMPORT_STAT_NO_EXIST) {
                #if MICROPY_MODULE_WEAK_LINKS
                // check if there is a weak link to this module
                if (i == mod_len) {
                    mp_map_elem_t *el = mp_map_lookup((mp_map_t*)&mp_builtin_module_weak_links_map, MP_OBJ_NEW_QSTR(mod_name), MP_MAP_LOOKUP);
                    if (el == NULL) {
                        goto no_exist;
                    }
                    // found weak linked module
                    module_obj = el->value;
                } else {
                    no_exist:
                #else
                {
                #endif
                    // couldn't find the file, so fail
                    if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
                        mp_raise_msg(&mp_type_ImportError, "module not found");
                    } else {
                        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ImportError,
                            "no module named '%q'", mod_name));
                    }
                }
            } else {
                // found the file, so get the module
                module_obj = mp_module_get(mod_name);
            }

            if (module_obj == MP_OBJ_NULL) {
                // module not already loaded, so load it!

                module_obj = mp_obj_new_module(mod_name);

                // if args[3] (fromtuple) has magic value False, set up
                // this module for command-line "-m" option (set module's
                // name to __main__ instead of real name).
                if (i == mod_len && fromtuple == mp_const_false) {
                    mp_obj_module_t *o = MP_OBJ_TO_PTR(module_obj);
                    mp_obj_dict_store(MP_OBJ_FROM_PTR(o->globals), MP_OBJ_NEW_QSTR(MP_QSTR___name__), MP_OBJ_NEW_QSTR(MP_QSTR___main__));
                    #if MICROPY_CPYTHON_COMPAT
                    // Store module as "__main__" in the dictionary of loaded modules (returned by sys.modules).
                    mp_obj_dict_store(MP_OBJ_FROM_PTR(&MP_STATE_VM(mp_loaded_modules_dict)), MP_OBJ_NEW_QSTR(MP_QSTR___main__), module_obj);
                    // Store real name in "__main__" attribute. Choosen semi-randonly, to reuse existing qstr's.
                    mp_obj_dict_store(MP_OBJ_FROM_PTR(o->globals), MP_OBJ_NEW_QSTR(MP_QSTR___main__), MP_OBJ_NEW_QSTR(mod_name));
                    #endif
                }

                if (stat == MP_IMPORT_STAT_DIR) {
                    DEBUG_printf("%.*s is dir\n", vstr_len(&path), vstr_str(&path));
                    // https://docs.python.org/3/reference/import.html
                    // "Specifically, any module that contains a __path__ attribute is considered a package."
                    mp_store_attr(module_obj, MP_QSTR___path__, mp_obj_new_str(vstr_str(&path), vstr_len(&path), false));
                    size_t orig_path_len = path.len;
                    vstr_add_char(&path, PATH_SEP_CHAR);
                    vstr_add_str(&path, "__init__.py");
                    if (stat_file_py_or_mpy(&path) != MP_IMPORT_STAT_FILE) {
                        //mp_warning("%s is imported as namespace package", vstr_str(&path));
                    } else {
                        do_load(module_obj, &path);
                    }
                    path.len = orig_path_len;
                } else { // MP_IMPORT_STAT_FILE
                    do_load(module_obj, &path);
                    // TODO: We cannot just break here, at the very least, we must execute
                    // trailer code below. But otherwise if there're remaining components,
                    // that would be (??) object path within module, not modules path within FS.
                    // break;
                }
            }
            if (outer_module_obj != MP_OBJ_NULL) {
                qstr s = qstr_from_strn(mod_str + last, i - last);
                mp_store_attr(outer_module_obj, s, module_obj);
            }
            outer_module_obj = module_obj;
            if (top_module_obj == MP_OBJ_NULL) {
                top_module_obj = module_obj;
            }
            last = i + 1;
        }
    }

    if (i < mod_len) {
        // we loaded a package, now need to load objects from within that package
        // TODO
        assert(0);
    }

    // If fromlist is not empty, return leaf module
    if (fromtuple != mp_const_none) {
        return module_obj;
    }
    // Otherwise, we need to return top-level package
    return top_module_obj;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_builtin___import___obj, 1, 5, mp_builtin___import__);