mirror of https://github.com/python/cpython
134 lines
4.2 KiB
C
134 lines
4.2 KiB
C
/* bytes to hex implementation */
|
|
|
|
#include "Python.h"
|
|
|
|
#include "pystrhex.h"
|
|
|
|
static PyObject *_Py_strhex_impl(const char* argbuf, const Py_ssize_t arglen,
|
|
const PyObject* sep, int bytes_per_sep_group,
|
|
const int return_bytes)
|
|
{
|
|
PyObject *retval;
|
|
Py_UCS1* retbuf;
|
|
Py_ssize_t i, j, resultlen = 0;
|
|
Py_UCS1 sep_char = 0;
|
|
unsigned int abs_bytes_per_sep;
|
|
|
|
if (sep) {
|
|
Py_ssize_t seplen = PyObject_Length((PyObject*)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);
|
|
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 ((size_t)abs_bytes_per_sep >= (size_t)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(resultlen);
|
|
if (!retbuf)
|
|
return PyErr_NoMemory();
|
|
retval = NULL; /* silence a compiler warning, assigned later. */
|
|
} else {
|
|
retval = PyUnicode_New(resultlen, 127);
|
|
if (!retval)
|
|
return NULL;
|
|
retbuf = PyUnicode_1BYTE_DATA(retval);
|
|
}
|
|
|
|
/* 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, resultlen);
|
|
PyMem_Free(retbuf);
|
|
}
|
|
#ifdef Py_DEBUG
|
|
else {
|
|
assert(_PyUnicode_CheckConsistency(retval, 1));
|
|
}
|
|
#endif
|
|
|
|
return retval;
|
|
}
|
|
|
|
PyObject * _Py_strhex(const char* argbuf, const Py_ssize_t arglen)
|
|
{
|
|
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, 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);
|
|
}
|