py/builtinimport: Refactor module importing.

Simplify and document/comment the handling of builtin import for:
- already-loaded modules
- built-in modules
- built-in umodules (formerly weak links)
- filesystem modules

Retains existing functionality with smaller code size but should also
facilitate potential new features (built-in packages, controlling the
frozen path).

Also makes the (unix-only) -m behavior a bit more obvious and configurable.

Code size change with this commit:

   bare-arm:    +0 +0.000%
minimal x86:   -64 -0.039%
   unix x64:   -32 -0.006%
unix nanbox:    -4 -0.001%
      stm32:  -184 -0.047% PYBV10
     cc3200:  -120 -0.065%
    esp8266:  -228 -0.033% GENERIC
      esp32:  -268 -0.018% GENERIC[incl +16(data)]
        nrf:  -152 -0.087% pca10040
        rp2:  -256 -0.052% PICO
       samd:   -80 -0.057% ADAFRUIT_ITSYBITSY_M4_EXPRESS
This commit is contained in:
Jim Mussared 2020-02-26 15:24:09 +11:00 committed by Damien George
parent 851ecb2da1
commit a7fa18c203
6 changed files with 337 additions and 246 deletions

View File

@ -86,6 +86,7 @@
#define MICROPY_OPT_MAP_LOOKUP_CACHE (1)
#endif
#define MICROPY_MODULE_WEAK_LINKS (1)
#define MICROPY_MODULE_OVERRIDE_MAIN_IMPORT (1)
#define MICROPY_CAN_OVERRIDE_BUILTINS (1)
#define MICROPY_VFS_POSIX_FILE (1)
#define MICROPY_PY_FUNCTION_ATTRS (1)

View File

@ -60,6 +60,7 @@
#define MICROPY_STREAMS_POSIX_API (1)
#define MICROPY_OPT_COMPUTED_GOTO (0)
#define MICROPY_MODULE_WEAK_LINKS (1)
#define MICROPY_MODULE_OVERRIDE_MAIN_IMPORT (1)
#define MICROPY_CAN_OVERRIDE_BUILTINS (1)
#define MICROPY_VFS_POSIX_FILE (1)
#define MICROPY_PY_FUNCTION_ATTRS (1)

View File

@ -5,6 +5,7 @@
*
* Copyright (c) 2013-2019 Damien P. George
* Copyright (c) 2014 Paul Sokolovsky
* Copyright (c) 2021 Jim Mussared
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
@ -46,7 +47,8 @@
#if MICROPY_ENABLE_EXTERNAL_IMPORT
#define PATH_SEP_CHAR '/'
// Must be a string of one byte.
#define PATH_SEP_CHAR "/"
bool mp_obj_is_package(mp_obj_t module) {
mp_obj_t dest[2];
@ -54,9 +56,11 @@ bool mp_obj_is_package(mp_obj_t module) {
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) {
// Wrapper for mp_import_stat (which is provided by the port, and typically
// uses mp_vfs_import_stat) to also search frozen modules. Given an exact
// path to a file or directory (e.g. "foo/bar", foo/bar.py" or "foo/bar.mpy"),
// will return whether the path is a file, directory, or doesn't exist.
STATIC mp_import_stat_t stat_path_or_frozen(const char *path) {
#if MICROPY_MODULE_FROZEN
mp_import_stat_t st = mp_frozen_stat(path);
if (st != MP_IMPORT_STAT_NO_EXIST) {
@ -66,15 +70,18 @@ STATIC mp_import_stat_t mp_import_stat_any(const char *path) {
return mp_import_stat(path);
}
// Given a path to a .py file, try and find this path as either a .py or .mpy
// in either the filesystem or frozen modules.
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));
mp_import_stat_t stat = stat_path_or_frozen(vstr_null_terminated_str(path));
if (stat == MP_IMPORT_STAT_FILE) {
return stat;
}
#if MICROPY_PERSISTENT_CODE_LOAD
// Didn't find .py -- try the .mpy instead by inserting an 'm' into the '.py'.
vstr_ins_byte(path, path->len - 2, 'm');
stat = mp_import_stat_any(vstr_null_terminated_str(path));
stat = stat_path_or_frozen(vstr_null_terminated_str(path));
if (stat == MP_IMPORT_STAT_FILE) {
return stat;
}
@ -83,8 +90,10 @@ STATIC mp_import_stat_t stat_file_py_or_mpy(vstr_t *path) {
return MP_IMPORT_STAT_NO_EXIST;
}
// Given an import path (e.g. "foo/bar"), try and find "foo/bar" (a directory)
// or "foo/bar.(m)py" in either the filesystem or frozen modules.
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));
mp_import_stat_t stat = stat_path_or_frozen(vstr_null_terminated_str(path));
DEBUG_printf("stat %s: %d\n", vstr_str(path), stat);
if (stat == MP_IMPORT_STAT_DIR) {
return stat;
@ -95,14 +104,16 @@ STATIC mp_import_stat_t stat_dir_or_file(vstr_t *path) {
return stat_file_py_or_mpy(path);
}
STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *dest) {
// Given a top-level module, try and find it in each of the sys.path entries
// via stat_dir_or_file.
STATIC mp_import_stat_t stat_top_level_dir_or_file(qstr mod_name, vstr_t *dest) {
DEBUG_printf("stat_top_level_dir_or_file: '%s'\n", qstr_str(mod_name));
#if MICROPY_PY_SYS
// extract the list of paths
size_t path_num;
mp_obj_t *path_items;
mp_obj_list_get(mp_sys_path, &path_num, &path_items);
if (path_num != 0) {
if (path_num > 0) {
// go through each path looking for a directory or file
for (size_t i = 0; i < path_num; i++) {
vstr_reset(dest);
@ -110,9 +121,9 @@ STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *d
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_char(dest, PATH_SEP_CHAR[0]);
}
vstr_add_strn(dest, file_str, file_len);
vstr_add_str(dest, qstr_str(mod_name));
mp_import_stat_t stat = stat_dir_or_file(dest);
if (stat != MP_IMPORT_STAT_NO_EXIST) {
return stat;
@ -124,8 +135,9 @@ STATIC mp_import_stat_t find_file(const char *file_str, uint file_len, vstr_t *d
}
#endif
// mp_sys_path is empty, so just use the given file name
vstr_add_strn(dest, file_str, file_len);
// mp_sys_path is empty (or not enabled), so just stat the given path
// directly.
vstr_add_str(dest, qstr_str(mod_name));
return stat_dir_or_file(dest);
}
@ -189,7 +201,6 @@ STATIC void do_load(mp_obj_t module_obj, vstr_t *file) {
#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.
@ -209,6 +220,8 @@ STATIC void do_load(mp_obj_t module_obj, vstr_t *file) {
}
#endif
#endif // MICROPY_MODULE_FROZEN
// 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_HAS_FILE_READER && MICROPY_PERSISTENT_CODE_LOAD
@ -232,15 +245,212 @@ STATIC void do_load(mp_obj_t module_obj, vstr_t *file) {
#endif
}
STATIC void chop_component(const char *start, const char **end) {
const char *p = *end;
while (p > start) {
// Convert a relative (to the current module) import, going up "level" levels,
// into an absolute import.
STATIC void evaluate_relative_import(mp_int_t level, const char **module_name, size_t *module_name_len) {
// What we want to do here is to take the name of the current module,
// remove <level> trailing components, and concatenate the passed-in
// module name.
// For example, level=3, module_name="foo.bar", __name__="a.b.c.d" --> "a.foo.bar"
// "Relative imports use a module's __name__ attribute to determine that
// module's position in the package hierarchy."
// http://legacy.python.org/dev/peps/pep-0328/#relative-imports-and-name
mp_obj_t current_module_name_obj = mp_obj_dict_get(MP_OBJ_FROM_PTR(mp_globals_get()), MP_OBJ_NEW_QSTR(MP_QSTR___name__));
assert(current_module_name_obj != MP_OBJ_NULL);
#if MICROPY_MODULE_OVERRIDE_MAIN_IMPORT && MICROPY_CPYTHON_COMPAT
if (MP_OBJ_QSTR_VALUE(current_module_name_obj) == MP_QSTR___main__) {
// This is a module loaded by -m command-line switch (e.g. unix port),
// and so its __name__ has been set to "__main__". Get its real name
// that we stored during import in the __main__ attribute.
current_module_name_obj = mp_obj_dict_get(MP_OBJ_FROM_PTR(mp_globals_get()), MP_OBJ_NEW_QSTR(MP_QSTR___main__));
}
#endif
// If we have a __path__ in the globals dict, then we're a package.
bool is_pkg = mp_map_lookup(&mp_globals_get()->map, MP_OBJ_NEW_QSTR(MP_QSTR___path__), MP_MAP_LOOKUP);
#if DEBUG_PRINT
DEBUG_printf("Current module/package: ");
mp_obj_print_helper(MICROPY_DEBUG_PRINTER, current_module_name_obj, PRINT_REPR);
DEBUG_printf(", is_package: %d", is_pkg);
DEBUG_printf("\n");
#endif
size_t current_module_name_len;
const char *current_module_name = mp_obj_str_get_data(current_module_name_obj, &current_module_name_len);
const char *p = current_module_name + current_module_name_len;
if (is_pkg) {
// If we're evaluating relative to a package, then take off one fewer
// level (i.e. the relative search starts inside the package, rather
// than as a sibling of the package).
--level;
}
// Walk back 'level' dots (or run out of path).
while (level && p > current_module_name) {
if (*--p == '.') {
*end = p;
return;
--level;
}
}
*end = p;
// We must have some component left over to import from.
if (p == current_module_name) {
mp_raise_msg(&mp_type_ImportError, MP_ERROR_TEXT("can't perform relative import"));
}
// New length is len("<chopped path>.<module_name>"). Note: might be one byte
// more than we need if module_name is empty (for the extra . we will
// append).
uint new_module_name_len = (size_t)(p - current_module_name) + 1 + *module_name_len;
char *new_mod = mp_local_alloc(new_module_name_len);
memcpy(new_mod, current_module_name, p - current_module_name);
// Only append ".<module_name>" if there was one).
if (*module_name_len != 0) {
new_mod[p - current_module_name] = '.';
memcpy(new_mod + (p - current_module_name) + 1, *module_name, *module_name_len);
} else {
--new_module_name_len;
}
// Copy into a QSTR.
qstr new_mod_q = qstr_from_strn(new_mod, new_module_name_len);
mp_local_free(new_mod);
DEBUG_printf("Resolved base name for relative import: '%s'\n", qstr_str(new_mod_q));
*module_name = qstr_str(new_mod_q);
*module_name_len = new_module_name_len;
}
// Load a module at the specified absolute path, possibly as a submodule of the given outer module.
// full_mod_name: The full absolute path to this module (e.g. "foo.bar.baz").
// level_mod_name: The final component of the path (e.g. "baz").
// outer_module_obj: The parent module (we need to store this module as an
// attribute on it) (or MP_OBJ_NULL for top-level).
// path: The filesystem path where we found the parent module
// (or empty for a top level module).
// override_main: Whether to set the __name__ to "__main__" (and use __main__
// for the actual path).
STATIC mp_obj_t process_import_at_level(qstr full_mod_name, qstr level_mod_name, mp_obj_t outer_module_obj, vstr_t *path, bool override_main) {
mp_import_stat_t stat = MP_IMPORT_STAT_NO_EXIST;
// Exact-match of built-in (or already-loaded) takes priority.
mp_obj_t module_obj = mp_module_get_loaded_or_builtin(full_mod_name);
// Even if we find the module, go through the motions of searching for it
// because we may actually be in the process of importing a sub-module.
// So we need to (re-)find the correct path to be finding the sub-module
// on the next iteration of process_import_at_level.
if (outer_module_obj == MP_OBJ_NULL) {
DEBUG_printf("Searching for top-level module\n");
// First module in the dotted-name; search for a directory or file
// relative to all the locations in sys.path.
stat = stat_top_level_dir_or_file(full_mod_name, path);
// If the module "foo" doesn't exist on the filesystem, and it's not a
// builtin, try and find "ufoo" as a built-in. (This feature was
// formerly known as "weak links").
#if MICROPY_MODULE_WEAK_LINKS
if (stat == MP_IMPORT_STAT_NO_EXIST && module_obj == MP_OBJ_NULL) {
char *umodule_buf = vstr_str(path);
umodule_buf[0] = 'u';
strcpy(umodule_buf + 1, qstr_str(level_mod_name));
qstr umodule_name = qstr_from_str(umodule_buf);
module_obj = mp_module_get_builtin(umodule_name);
}
#endif
} else {
DEBUG_printf("Searching for sub-module\n");
// Add the current part of the module name to the path.
vstr_add_char(path, PATH_SEP_CHAR[0]);
vstr_add_str(path, qstr_str(level_mod_name));
// Because it's not top level, we already know which path the parent was found in.
stat = stat_dir_or_file(path);
}
DEBUG_printf("Current path: %.*s\n", (int)vstr_len(path), vstr_str(path));
if (module_obj == MP_OBJ_NULL) {
// Not a built-in and not already-loaded.
if (stat == MP_IMPORT_STAT_NO_EXIST) {
// And the file wasn't found -- fail.
#if MICROPY_ERROR_REPORTING <= MICROPY_ERROR_REPORTING_TERSE
mp_raise_msg(&mp_type_ImportError, MP_ERROR_TEXT("module not found"));
#else
mp_raise_msg_varg(&mp_type_ImportError, MP_ERROR_TEXT("no module named '%q'"), full_mod_name);
#endif
}
// Not a built-in but found on the filesystem, try and load it.
DEBUG_printf("Found path: %.*s\n", (int)vstr_len(path), vstr_str(path));
// Prepare for loading from the filesystem. Create a new shell module.
module_obj = mp_obj_new_module(full_mod_name);
#if MICROPY_MODULE_OVERRIDE_MAIN_IMPORT
// If this module is being loaded via -m on unix, then
// override __name__ to "__main__". Do this only for *modules*
// however - packages never have their names replaced, instead
// they're -m'ed using a special __main__ submodule in them. (This all
// apparently is done to not touch the package name itself, which is
// important for future imports).
if (override_main && stat != MP_IMPORT_STAT_DIR) {
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. Need this for
// resolving relative imports later. "__main__ was chosen
// 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(full_mod_name));
#endif
}
#endif // MICROPY_MODULE_OVERRIDE_MAIN_IMPORT
if (stat == MP_IMPORT_STAT_DIR) {
// Directory -- execute "path/__init__.py".
DEBUG_printf("%.*s is dir\n", (int)vstr_len(path), vstr_str(path));
// Store the __path__ attribute onto this module.
// 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)));
size_t orig_path_len = path->len;
vstr_add_str(path, PATH_SEP_CHAR "__init__.py");
if (stat_file_py_or_mpy(path) == MP_IMPORT_STAT_FILE) {
do_load(module_obj, path);
} else {
// No-op. Nothing to load.
// mp_warning("%s is imported as namespace package", vstr_str(&path));
}
// Remove /__init__.py suffix.
path->len = orig_path_len;
} else { // MP_IMPORT_STAT_FILE
// File -- execute "path.(m)py".
do_load(module_obj, path);
// Note: This should be the last component in the import path. If
// there are remaining components then it's an ImportError
// because the current path(the module that was just loaded) is
// not a package. This will be caught on the next iteration
// because the file will not exist.
}
}
if (outer_module_obj != MP_OBJ_NULL) {
// If it's a sub-module (not a built-in one), then make it available on
// the parent module.
mp_store_attr(outer_module_obj, level_mod_name, module_obj);
}
return module_obj;
}
mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) {
@ -253,9 +463,23 @@ mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) {
}
#endif
mp_obj_t module_name = args[0];
// This is the import path, with any leading dots stripped.
// "import foo.bar" --> module_name="foo.bar"
// "from foo.bar import baz" --> module_name="foo.bar"
// "from . import foo" --> module_name=""
// "from ...foo.bar import baz" --> module_name="foo.bar"
mp_obj_t module_name_obj = args[0];
// These are the imported names.
// i.e. "from foo.bar import baz, zap" --> fromtuple=("baz", "zap",)
// Note: There's a special case on the Unix port, where this is set to mp_const_false which means that it's __main__.
mp_obj_t fromtuple = mp_const_none;
// Level is the number of leading dots in a relative import.
// i.e. "from . import foo" --> level=1
// i.e. "from ...foo.bar import baz" --> level=3
mp_int_t level = 0;
if (n_args >= 4) {
fromtuple = args[3];
if (n_args >= 5) {
@ -266,211 +490,64 @@ mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) {
}
}
size_t mod_len;
const char *mod_str = mp_obj_str_get_data(module_name, &mod_len);
size_t module_name_len;
const char *module_name = mp_obj_str_get_data(module_name_obj, &module_name_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 absolute.
// 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_helper(MICROPY_DEBUG_PRINTER, this_name_q, PRINT_REPR);
DEBUG_printf(", is_package: %d", is_pkg);
DEBUG_printf("\n");
#endif
size_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);
}
while (level--) {
chop_component(this_name, &p);
}
// We must have some component left over to import from
if (p == this_name) {
mp_raise_msg(&mp_type_ImportError, MP_ERROR_TEXT("can't perform 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 = mp_local_alloc(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);
mp_local_free(new_mod);
DEBUG_printf("Resolved base name for relative import: '%s'\n", qstr_str(new_mod_q));
module_name = MP_OBJ_NEW_QSTR(new_mod_q);
mod_str = qstr_str(new_mod_q);
mod_len = new_mod_l;
// Turn "foo.bar" into "<current module minus 3 components>.foo.bar".
evaluate_relative_import(level, &module_name, &module_name_len);
}
if (mod_len == 0) {
if (module_name_len == 0) {
mp_raise_ValueError(NULL);
}
// 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");
DEBUG_printf("Starting module search for '%s'\n", module_name);
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));
// Search for the end of each component.
size_t current_component_start = 0;
for (size_t i = 1; i <= module_name_len; i++) {
if (i == module_name_len || module_name[i] == '.') {
// The module name up to this depth (e.g. foo.bar.baz).
qstr full_mod_name = qstr_from_strn(module_name, i);
// The current level name (e.g. baz).
qstr level_mod_name = qstr_from_strn(module_name + current_component_start, i - current_component_start);
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) {
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);
}
}
#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, MP_ERROR_TEXT("module not found"));
#else
mp_raise_msg_varg(&mp_type_ImportError, MP_ERROR_TEXT("no module named '%q'"), mod_name);
#endif
}
} else {
// found the file, so get the module
module_obj = mp_module_get(mod_name);
}
DEBUG_printf("Processing module: '%s' at level '%s'\n", qstr_str(full_mod_name), qstr_str(level_mod_name));
DEBUG_printf("Previous path: =%.*s=\n", (int)vstr_len(&path), vstr_str(&path));
if (module_obj == MP_OBJ_NULL) {
// module not already loaded, so load it!
#if MICROPY_MODULE_OVERRIDE_MAIN_IMPORT
// On unix, if this is being loaded via -m (magic mp_const_false),
// then handle that if it's the final component.
bool override_main = (i == module_name_len && fromtuple == mp_const_false);
#else
bool override_main = false;
#endif
module_obj = mp_obj_new_module(mod_name);
// Import this module.
mp_obj_t module_obj = process_import_at_level(full_mod_name, level_mod_name, outer_module_obj, &path, override_main);
// 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). Do this only
// for *modules* however - packages never have their names
// replaced, instead they're -m'ed using a special __main__
// submodule in them. (This all apparently is done to not
// touch package name itself, which is important for future
// imports).
if (i == mod_len && fromtuple == mp_const_false && stat != MP_IMPORT_STAT_DIR) {
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. Chosen 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)));
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);
// This should be the last component in the import path. If there are
// remaining components then it's an ImportError because the current path
// (the module that was just loaded) is not a package. This will be caught
// on the next iteration because the file will not exist.
}
}
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);
}
// Set this as the parent module, and remember the top-level module if it's the first.
outer_module_obj = module_obj;
if (top_module_obj == MP_OBJ_NULL) {
top_module_obj = module_obj;
}
last = i + 1;
current_component_start = i + 1;
}
}
// If fromlist is not empty, return leaf module
if (fromtuple != mp_const_none) {
return module_obj;
// If fromtuple is not empty, return leaf module
return outer_module_obj;
} else {
// Otherwise, we need to return top-level package
return top_module_obj;
}
// Otherwise, we need to return top-level package
return top_module_obj;
}
#else // MICROPY_ENABLE_EXTERNAL_IMPORT
@ -483,17 +560,19 @@ mp_obj_t mp_builtin___import__(size_t n_args, const mp_obj_t *args) {
// Check if module already exists, and return it if it does
qstr module_name_qstr = mp_obj_str_get_qstr(args[0]);
mp_obj_t module_obj = mp_module_get(module_name_qstr);
mp_obj_t module_obj = mp_module_get_loaded_or_builtin(module_name_qstr);
if (module_obj != MP_OBJ_NULL) {
return module_obj;
}
#if MICROPY_MODULE_WEAK_LINKS
// Check if there is a weak link to this module
module_obj = mp_module_search_umodule(qstr_str(module_name_qstr));
char umodule_buf[MICROPY_ALLOC_PATH_MAX];
umodule_buf[0] = 'u';
strcpy(umodule_buf + 1, args[0]);
qstr umodule_name_qstr = qstr_from_str(umodule_buf);
module_obj = mp_module_get_loaded_or_builtin(umodule_name_qstr);
if (module_obj != MP_OBJ_NULL) {
// Found weak-linked module
mp_module_call_init(module_name_qstr, module_obj);
return module_obj;
}
#endif

View File

@ -829,6 +829,12 @@ typedef double mp_float_t;
#define MICROPY_MODULE_WEAK_LINKS (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_EXTRA_FEATURES)
#endif
// Whether to enable importing foo.py with __name__ set to '__main__'
// Used by the unix port for the -m flag.
#ifndef MICROPY_MODULE_OVERRIDE_MAIN_IMPORT
#define MICROPY_MODULE_OVERRIDE_MAIN_IMPORT (0)
#endif
// Whether frozen modules are supported in the form of strings
#ifndef MICROPY_MODULE_FROZEN_STR
#define MICROPY_MODULE_FROZEN_STR (0)

View File

@ -35,6 +35,10 @@
#include "genhdr/moduledefs.h"
#if MICROPY_MODULE_BUILTIN_INIT
STATIC void mp_module_call_init(mp_obj_t module_name, mp_obj_t module_obj);
#endif
STATIC void module_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
(void)kind;
mp_obj_module_t *self = MP_OBJ_TO_PTR(self_in);
@ -245,47 +249,56 @@ STATIC const mp_rom_map_elem_t mp_builtin_module_table[] = {
MP_DEFINE_CONST_MAP(mp_builtin_module_map, mp_builtin_module_table);
// returns MP_OBJ_NULL if not found
mp_obj_t mp_module_get(qstr module_name) {
mp_map_t *mp_loaded_modules_map = &MP_STATE_VM(mp_loaded_modules_dict).map;
// lookup module
mp_map_elem_t *el = mp_map_lookup(mp_loaded_modules_map, MP_OBJ_NEW_QSTR(module_name), MP_MAP_LOOKUP);
// Tries to find a loaded module, otherwise attempts to load a builtin, otherwise MP_OBJ_NULL.
mp_obj_t mp_module_get_loaded_or_builtin(qstr module_name) {
// First try loaded modules.
mp_map_elem_t *elem = mp_map_lookup(&MP_STATE_VM(mp_loaded_modules_dict).map, MP_OBJ_NEW_QSTR(module_name), MP_MAP_LOOKUP);
if (el == NULL) {
// module not found, look for builtin module names
el = mp_map_lookup((mp_map_t *)&mp_builtin_module_map, MP_OBJ_NEW_QSTR(module_name), MP_MAP_LOOKUP);
if (el == NULL) {
if (!elem) {
#if MICROPY_MODULE_WEAK_LINKS
return mp_module_get_builtin(module_name);
#else
// Otherwise try builtin.
elem = mp_map_lookup((mp_map_t *)&mp_builtin_module_map, MP_OBJ_NEW_QSTR(module_name), MP_MAP_LOOKUP);
if (!elem) {
return MP_OBJ_NULL;
}
mp_module_call_init(module_name, el->value);
#if MICROPY_MODULE_BUILTIN_INIT
// If found, it's a newly loaded built-in, so init it.
mp_module_call_init(MP_OBJ_NEW_QSTR(module_name), elem->value);
#endif
#endif
}
// module found, return it
return el->value;
}
void mp_module_register(qstr qst, mp_obj_t module) {
mp_map_t *mp_loaded_modules_map = &MP_STATE_VM(mp_loaded_modules_dict).map;
mp_map_lookup(mp_loaded_modules_map, MP_OBJ_NEW_QSTR(qst), MP_MAP_LOOKUP_ADD_IF_NOT_FOUND)->value = module;
return elem->value;
}
#if MICROPY_MODULE_WEAK_LINKS
// Search for u"foo" in built-in modules, return MP_OBJ_NULL if not found
mp_obj_t mp_module_search_umodule(const char *module_str) {
for (size_t i = 0; i < MP_ARRAY_SIZE(mp_builtin_module_table); ++i) {
const mp_map_elem_t *entry = (const mp_map_elem_t *)&mp_builtin_module_table[i];
const char *key = qstr_str(MP_OBJ_QSTR_VALUE(entry->key));
if (key[0] == 'u' && strcmp(&key[1], module_str) == 0) {
return (mp_obj_t)entry->value;
}
// Tries to find a loaded module, otherwise attempts to load a builtin, otherwise MP_OBJ_NULL.
mp_obj_t mp_module_get_builtin(qstr module_name) {
// Try builtin.
mp_map_elem_t *elem = mp_map_lookup((mp_map_t *)&mp_builtin_module_map, MP_OBJ_NEW_QSTR(module_name), MP_MAP_LOOKUP);
if (!elem) {
return MP_OBJ_NULL;
}
return MP_OBJ_NULL;
#if MICROPY_MODULE_BUILTIN_INIT
// If found, it's a newly loaded built-in, so init it.
mp_module_call_init(MP_OBJ_NEW_QSTR(module_name), elem->value);
#endif
return elem->value;
}
#endif
#if MICROPY_MODULE_BUILTIN_INIT
void mp_module_call_init(qstr module_name, mp_obj_t module_obj) {
STATIC void mp_module_register(mp_obj_t module_name, mp_obj_t module) {
mp_map_t *mp_loaded_modules_map = &MP_STATE_VM(mp_loaded_modules_dict).map;
mp_map_lookup(mp_loaded_modules_map, module_name, MP_MAP_LOOKUP_ADD_IF_NOT_FOUND)->value = module;
}
STATIC void mp_module_call_init(mp_obj_t module_name, mp_obj_t module_obj) {
// Look for __init__ and call it if it exists
mp_obj_t dest[2];
mp_load_method_maybe(module_obj, MP_QSTR___init__, dest);

View File

@ -30,18 +30,9 @@
extern const mp_map_t mp_builtin_module_map;
mp_obj_t mp_module_get(qstr module_name);
void mp_module_register(qstr qstr, mp_obj_t module);
mp_obj_t mp_module_search_umodule(const char *module_str);
#if MICROPY_MODULE_BUILTIN_INIT
void mp_module_call_init(qstr module_name, mp_obj_t module_obj);
#else
static inline void mp_module_call_init(qstr module_name, mp_obj_t module_obj) {
(void)module_name;
(void)module_obj;
}
mp_obj_t mp_module_get_loaded_or_builtin(qstr module_name);
#if MICROPY_MODULE_WEAK_LINKS
mp_obj_t mp_module_get_builtin(qstr module_name);
#endif
#endif // MICROPY_INCLUDED_PY_OBJMODULE_H