41 lines
1.4 KiB
C
41 lines
1.4 KiB
C
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/* This example demonstrates the following features in a native module:
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- defining a simple function exposed to Python
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- defining a local, helper C function
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- getting and creating integer objects
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*/
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// Include the header file to get access to the MicroPython API
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#include "py/dynruntime.h"
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// Helper function to compute factorial
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STATIC mp_int_t factorial_helper(mp_int_t x) {
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if (x == 0) {
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return 1;
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}
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return x * factorial_helper(x - 1);
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}
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// This is the function which will be called from Python, as factorial(x)
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STATIC mp_obj_t factorial(mp_obj_t x_obj) {
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// Extract the integer from the MicroPython input object
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mp_int_t x = mp_obj_get_int(x_obj);
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// Calculate the factorial
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mp_int_t result = factorial_helper(x);
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// Convert the result to a MicroPython integer object and return it
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return mp_obj_new_int(result);
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}
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// Define a Python reference to the function above
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(factorial_obj, factorial);
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// This is the entry point and is called when the module is imported
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mp_obj_t mpy_init(mp_obj_fun_bc_t *self, size_t n_args, size_t n_kw, mp_obj_t *args) {
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// This must be first, it sets up the globals dict and other things
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MP_DYNRUNTIME_INIT_ENTRY
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// Make the function available in the module's namespace
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mp_store_global(MP_QSTR_factorial, MP_OBJ_FROM_PTR(&factorial_obj));
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// This must be last, it restores the globals dict
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MP_DYNRUNTIME_INIT_EXIT
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}
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