diff options
Diffstat (limited to 'Python')
| -rw-r--r-- | Python/pystrhex.c | 90 |
1 files changed, 80 insertions, 10 deletions
diff --git a/Python/pystrhex.c b/Python/pystrhex.c index 028f187c70..695a3c394e 100644 --- a/Python/pystrhex.c +++ b/Python/pystrhex.c @@ -5,40 +5,96 @@ #include "pystrhex.h" static PyObject *_Py_strhex_impl(const char* argbuf, const Py_ssize_t arglen, - int return_bytes) + const PyObject* sep, int bytes_per_sep_group, + const int return_bytes) { PyObject *retval; Py_UCS1* retbuf; - Py_ssize_t i, j; + Py_ssize_t i, j, resultlen = 0; + Py_UCS1 sep_char; + unsigned int abs_bytes_per_sep; + + if (sep) { + Py_ssize_t seplen = PyObject_Length(sep); + if (seplen < 0) { + return NULL; + } + if (seplen != 1) { + PyErr_SetString(PyExc_ValueError, "sep must be length 1."); + return NULL; + } + if (PyUnicode_Check(sep)) { + if (PyUnicode_READY(sep)) + return NULL; + if (PyUnicode_KIND(sep) != PyUnicode_1BYTE_KIND) { + PyErr_SetString(PyExc_ValueError, "sep must be ASCII."); + return NULL; + } + sep_char = PyUnicode_READ_CHAR(sep, 0); + } else if (PyBytes_Check(sep)) { + sep_char = PyBytes_AS_STRING(sep)[0]; + } else { + PyErr_SetString(PyExc_TypeError, "sep must be str or bytes."); + return NULL; + } + if (sep_char > 127 && !return_bytes) { + PyErr_SetString(PyExc_ValueError, "sep must be ASCII."); + return NULL; + } + } else { + bytes_per_sep_group = 0; + } assert(arglen >= 0); - if (arglen > PY_SSIZE_T_MAX / 2) + abs_bytes_per_sep = abs(bytes_per_sep_group); + if (bytes_per_sep_group && arglen > 0) { + /* How many sep characters we'll be inserting. */ + resultlen = (arglen - 1) / abs_bytes_per_sep; + } + /* Bounds checking for our Py_ssize_t indices. */ + if (arglen >= PY_SSIZE_T_MAX / 2 - resultlen) { return PyErr_NoMemory(); + } + resultlen += arglen * 2; + + if (abs_bytes_per_sep >= arglen) { + bytes_per_sep_group = 0; + abs_bytes_per_sep = 0; + } if (return_bytes) { /* If _PyBytes_FromSize() were public we could avoid malloc+copy. */ - retbuf = (Py_UCS1*) PyMem_Malloc(arglen*2); + retbuf = (Py_UCS1*) PyMem_Malloc(resultlen); if (!retbuf) return PyErr_NoMemory(); retval = NULL; /* silence a compiler warning, assigned later. */ } else { - retval = PyUnicode_New(arglen*2, 127); + retval = PyUnicode_New(resultlen, 127); if (!retval) return NULL; retbuf = PyUnicode_1BYTE_DATA(retval); } - /* make hex version of string, taken from shamodule.c */ - for (i=j=0; i < arglen; i++) { + /* Hexlify */ + for (i=j=0; i < arglen; ++i) { + assert(j < resultlen); unsigned char c; c = (argbuf[i] >> 4) & 0xf; retbuf[j++] = Py_hexdigits[c]; c = argbuf[i] & 0xf; retbuf[j++] = Py_hexdigits[c]; + if (bytes_per_sep_group && i < arglen - 1) { + Py_ssize_t anchor; + anchor = (bytes_per_sep_group > 0) ? (arglen - 1 - i) : (i + 1); + if (anchor % abs_bytes_per_sep == 0) { + retbuf[j++] = sep_char; + } + } } + assert(j == resultlen); if (return_bytes) { - retval = PyBytes_FromStringAndSize((const char *)retbuf, arglen*2); + retval = PyBytes_FromStringAndSize((const char *)retbuf, resultlen); PyMem_Free(retbuf); } #ifdef Py_DEBUG @@ -52,12 +108,26 @@ static PyObject *_Py_strhex_impl(const char* argbuf, const Py_ssize_t arglen, PyObject * _Py_strhex(const char* argbuf, const Py_ssize_t arglen) { - return _Py_strhex_impl(argbuf, arglen, 0); + return _Py_strhex_impl(argbuf, arglen, NULL, 0, 0); } /* Same as above but returns a bytes() instead of str() to avoid the * need to decode the str() when bytes are needed. */ PyObject * _Py_strhex_bytes(const char* argbuf, const Py_ssize_t arglen) { - return _Py_strhex_impl(argbuf, arglen, 1); + return _Py_strhex_impl(argbuf, arglen, NULL, 0, 1); +} + +/* These variants include support for a separator between every N bytes: */ + +PyObject * _Py_strhex_with_sep(const char* argbuf, const Py_ssize_t arglen, const PyObject* sep, const int bytes_per_group) +{ + return _Py_strhex_impl(argbuf, arglen, sep, bytes_per_group, 0); +} + +/* Same as above but returns a bytes() instead of str() to avoid the + * need to decode the str() when bytes are needed. */ +PyObject * _Py_strhex_bytes_with_sep(const char* argbuf, const Py_ssize_t arglen, const PyObject* sep, const int bytes_per_group) +{ + return _Py_strhex_impl(argbuf, arglen, sep, bytes_per_group, 1); } |