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py: Make int.from_bytes a classmethod; support arbitrary length buf.
1 parent 8a1cab9 commit 5213eb3

1 file changed

Lines changed: 16 additions & 7 deletions

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py/objint.c

Lines changed: 16 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -265,18 +265,27 @@ mp_obj_t mp_obj_int_binary_op_extra_cases(int op, mp_obj_t lhs_in, mp_obj_t rhs_
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return MP_OBJ_NULL;
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}
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// this is a classmethod
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STATIC mp_obj_t int_from_bytes(uint n_args, const mp_obj_t *args) {
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// TODO: Support long ints
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// TODO: Support byteorder param (assumes 'little' at the moment)
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// TODO: Support signed param (assumes signed=False at the moment)
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// get the buffer info
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buffer_info_t bufinfo;
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mp_get_buffer_raise(args[0], &bufinfo);
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mp_get_buffer_raise(args[1], &bufinfo);
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assert(bufinfo.len >= sizeof(machine_int_t));
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// TODO: Support long ints
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// TODO: Support byteorder param
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// TODO: Support signed param
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return mp_obj_new_int_from_uint(*(machine_uint_t*)bufinfo.buf);
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// convert the bytes to an integer
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machine_uint_t value = 0;
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for (uint i = 0; i < bufinfo.len; i++) {
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value += ((byte*)bufinfo.buf)[i];
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}
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return mp_obj_new_int_from_uint(value);
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_from_bytes_obj, 1, 3, int_from_bytes);
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STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_from_bytes_fun_obj, 2, 3, int_from_bytes);
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STATIC MP_DEFINE_CONST_CLASSMETHOD_OBJ(int_from_bytes_obj, (const mp_obj_t)&int_from_bytes_fun_obj);
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STATIC mp_obj_t int_to_bytes(uint n_args, const mp_obj_t *args) {
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machine_int_t val = mp_obj_int_get_checked(args[0]);

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