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|
- from cpython cimport PyBytes_AsString
-
- #from cpython cimport PyByteArray_AsString # cython still not exports that
- cdef extern from "Python.h":
- char* PyByteArray_AsString(bytearray ba) except NULL
-
- from libc.stdint cimport uint32_t, uint64_t, uintmax_t
-
- def _websocket_mask_cython(object mask, object data):
- """Note, this function mutates it's `data` argument
- """
- cdef:
- Py_ssize_t data_len, i
- # bit operations on signed integers are implementation-specific
- unsigned char * in_buf
- const unsigned char * mask_buf
- uint32_t uint32_msk
- uint64_t uint64_msk
-
- assert len(mask) == 4
-
- if not isinstance(mask, bytes):
- mask = bytes(mask)
-
- if isinstance(data, bytearray):
- data = <bytearray>data
- else:
- data = bytearray(data)
-
- data_len = len(data)
- in_buf = <unsigned char*>PyByteArray_AsString(data)
- mask_buf = <const unsigned char*>PyBytes_AsString(mask)
- uint32_msk = (<uint32_t*>mask_buf)[0]
-
- # TODO: align in_data ptr to achieve even faster speeds
- # does it need in python ?! malloc() always aligns to sizeof(long) bytes
-
- if sizeof(size_t) >= 8:
- uint64_msk = uint32_msk
- uint64_msk = (uint64_msk << 32) | uint32_msk
-
- while data_len >= 8:
- (<uint64_t*>in_buf)[0] ^= uint64_msk
- in_buf += 8
- data_len -= 8
-
-
- while data_len >= 4:
- (<uint32_t*>in_buf)[0] ^= uint32_msk
- in_buf += 4
- data_len -= 4
-
- for i in range(0, data_len):
- in_buf[i] ^= mask_buf[i]
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