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#define PY_SSIZE_T_CLEAN
#include "Python.h"
#include <errno.h>
#include "lzf.h"
#if PY_MAJOR_VERSION >= 3
#define PYBYTES_FSAS PyBytes_FromStringAndSize
#define PyInt_CheckExact(pyobj) 0
#define PyInt_AsLong(pyobj) 0
#else
#define PYBYTES_FSAS PyString_FromStringAndSize
#endif
#if PY_MAJOR_VERSION == 2 && PY_MINOR_VERSION <= 4
#define Py_ssize_t ssize_t
#endif
static PyObject *
python_compress(PyObject *self, PyObject *args) {
char *input, *output;
Py_ssize_t inlen;
PyObject *pyoutlen = Py_None;
long outlen;
PyObject *result;
if (!PyArg_ParseTuple(args, "s#|O", &input, &inlen, &pyoutlen))
return NULL;
if (pyoutlen == Py_None)
outlen = inlen - 1;
else if (PyInt_CheckExact(pyoutlen))
outlen = PyInt_AsLong(pyoutlen);
else if (PyLong_CheckExact(pyoutlen))
outlen = PyLong_AsLong(pyoutlen);
else {
PyErr_SetString(PyExc_TypeError, "max_len must be an integer");
return NULL;
}
if (inlen == 1) outlen++; /* work around for what looks like a liblzf bug */
if (outlen <= 0) {
PyErr_SetString(PyExc_ValueError, "max_len must be > 0");
return NULL;
}
output = (char *)malloc(outlen + 1);
if (output == NULL) {
PyErr_SetString(PyExc_MemoryError, "out of memory");
return NULL;
}
outlen = lzf_compress(input, inlen, output, outlen + 1);
if (outlen)
result = PYBYTES_FSAS(output, outlen);
else {
Py_XINCREF(Py_None);
result = Py_None;
}
free(output);
return result;
}
static PyObject *
python_decompress(PyObject *self, PyObject *args) {
char *input, *output;
Py_ssize_t inlen;
long outlen;
PyObject *result;
if (!PyArg_ParseTuple(args, "s#l", &input, &inlen, &outlen))
return NULL;
if (outlen < 0) {
PyErr_SetString(PyExc_ValueError, "max_len cannot be less than 0");
return NULL;
}
output = (char *)malloc(outlen);
outlen = lzf_decompress(input, inlen, output, outlen);
if (outlen)
result = PYBYTES_FSAS(output, outlen);
else {
if (errno == EINVAL) {
PyErr_SetString(PyExc_ValueError, "error in compressed data");
free(output);
return NULL;
}
Py_XINCREF(Py_None);
result = Py_None;
}
free(output);
return result;
}
static PyMethodDef methods[] = {
{"compress", python_compress, METH_VARARGS,
"compress(input, max_length=None)\n\
\n\
return the compressed string, or None if it doesn't compress to smaller \n\
than the original\n\
\n\
takes an optional second parameter, for specifying a maximum compressed \n\
length (default is one less than the length of the original)"},
{"decompress", python_decompress, METH_VARARGS,
"decompress(input, max_length)\n\
\n\
return the decompressed string\n\
\n\
will return None if the string doesn't decompress to within max_length bytes"},
{NULL, NULL, 0, NULL}
};
#if PY_MAJOR_VERSION >= 3
static struct PyModuleDef lzfmodule = {
PyModuleDef_HEAD_INIT,
"lzf", "", -1, methods,
NULL, NULL, NULL, NULL
};
PyMODINIT_FUNC
PyInit_lzf(void) {
PyObject *module = PyModule_Create(&lzfmodule);
return module;
}
#else
PyMODINIT_FUNC
initlzf(void) {
Py_InitModule("lzf", methods);
}
#endif
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