From d2384efa809953152c57cbda4c339dfbaa64cf29 Mon Sep 17 00:00:00 2001 From: Damien George Date: Tue, 22 Oct 2019 01:06:34 +1100 Subject: py: Automatically provide weak links from "foo" to "ufoo" module name. This commit implements automatic module weak links for all built-in modules, by searching for "ufoo" in the built-in module list if "foo" cannot be found. This means that all modules named "ufoo" are always available as "foo". Also, a port can no longer add any other weak links, which makes strict the definition of a weak link. It saves some code size (about 100-200 bytes) on ports that previously had lots of weak links. Some changes from the previous behaviour: - It doesn't intern the non-u module names (eg "foo" is not interned), which saves code size, but will mean that "import foo" creates a new qstr (namely "foo") in RAM (unless the importing module is frozen). - help('modules') no longer lists non-u module names, only the u-variants; this reduces duplication in the help listing. Weak links are effectively the same as having a set of symbolic links on the filesystem that is searched last. So an "import foo" will search built-in modules first, then all paths in sys.path, then weak links last, importing "ufoo" if it exists. Thus a file called "foo.py" somewhere in sys.path will still have precedence over the weak link of "foo" to "ufoo". See issues: #1740, #4449, #5229, #5241. --- py/builtinimport.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) (limited to 'py/builtinimport.c') diff --git a/py/builtinimport.c b/py/builtinimport.c index 008a21dcff..b9f6c2ab2d 100644 --- a/py/builtinimport.c +++ b/py/builtinimport.c @@ -3,7 +3,7 @@ * * The MIT License (MIT) * - * Copyright (c) 2013, 2014 Damien P. George + * Copyright (c) 2013-2019 Damien P. George * Copyright (c) 2014 Paul Sokolovsky * * Permission is hereby granted, free of charge, to any person obtaining a copy @@ -381,21 +381,18 @@ mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) { DEBUG_printf("Current path: %.*s\n", vstr_len(&path), vstr_str(&path)); if (stat == MP_IMPORT_STAT_NO_EXIST) { + module_obj = MP_OBJ_NULL; #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; + module_obj = mp_module_search_umodule(mod_str); + if (module_obj != MP_OBJ_NULL) { + // found weak linked module + mp_module_call_init(mod_name, module_obj); } - // found weak linked module - module_obj = el->value; - mp_module_call_init(mod_name, module_obj); - } else { - no_exist: - #else - { + } #endif + if (module_obj == MP_OBJ_NULL) { // couldn't find the file, so fail if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) { mp_raise_msg(&mp_type_ImportError, "module not found"); @@ -492,11 +489,11 @@ mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) { #if MICROPY_MODULE_WEAK_LINKS // Check if there is a weak link to this module - mp_map_elem_t *el = mp_map_lookup((mp_map_t*)&mp_builtin_module_weak_links_map, MP_OBJ_NEW_QSTR(module_name_qstr), MP_MAP_LOOKUP); - if (el != NULL) { + module_obj = mp_module_search_umodule(qstr_str(module_name_qstr)); + if (module_obj != MP_OBJ_NULL) { // Found weak-linked module - mp_module_call_init(module_name_qstr, el->value); - return el->value; + mp_module_call_init(module_name_qstr, module_obj); + return module_obj; } #endif -- cgit v1.2.3