brotli/python/brotlimodule.cc
2016-06-23 11:02:53 +02:00

304 lines
8.9 KiB
C++

#define PY_SSIZE_T_CLEAN 1
#include <Python.h>
#include <bytesobject.h>
#include <vector>
#include "../enc/encode.h"
#include "../dec/decode.h"
#include "../tools/version.h"
#if PY_MAJOR_VERSION >= 3
#define PyInt_Check PyLong_Check
#define PyInt_AsLong PyLong_AsLong
#endif
static PyObject *BrotliError;
static int as_bounded_int(PyObject *o, int* result, int lower_bound, int upper_bound) {
long value = PyInt_AsLong(o);
if ((value < (long) lower_bound) || (value > (long) upper_bound)) {
return 0;
}
*result = (int) value;
return 1;
}
static int mode_convertor(PyObject *o, BrotliEncoderMode *mode) {
if (!PyInt_Check(o)) {
PyErr_SetString(BrotliError, "Invalid mode");
return 0;
}
int mode_value = -1;
if (!as_bounded_int(o, &mode_value, 0, 255)) {
PyErr_SetString(BrotliError, "Invalid mode");
return 0;
}
*mode = (BrotliEncoderMode) mode_value;
if (*mode != BROTLI_MODE_GENERIC &&
*mode != BROTLI_MODE_TEXT &&
*mode != BROTLI_MODE_FONT) {
PyErr_SetString(BrotliError, "Invalid mode");
return 0;
}
return 1;
}
static int quality_convertor(PyObject *o, int *quality) {
if (!PyInt_Check(o)) {
PyErr_SetString(BrotliError, "Invalid quality");
return 0;
}
if (!as_bounded_int(o, quality, 0, 11)) {
PyErr_SetString(BrotliError, "Invalid quality. Range is 0 to 11.");
return 0;
}
return 1;
}
static int lgwin_convertor(PyObject *o, int *lgwin) {
if (!PyInt_Check(o)) {
PyErr_SetString(BrotliError, "Invalid lgwin");
return 0;
}
if (!as_bounded_int(o, lgwin, 10, 24)) {
PyErr_SetString(BrotliError, "Invalid lgwin. Range is 10 to 24.");
return 0;
}
return 1;
}
static int lgblock_convertor(PyObject *o, int *lgblock) {
if (!PyInt_Check(o)) {
PyErr_SetString(BrotliError, "Invalid lgblock");
return 0;
}
if (!as_bounded_int(o, lgblock, 0, 24) || (*lgblock != 0 && *lgblock < 16)) {
PyErr_SetString(BrotliError, "Invalid lgblock. Can be 0 or in range 16 to 24.");
return 0;
}
return 1;
}
PyDoc_STRVAR(compress__doc__,
"Compress a byte string.\n"
"\n"
"Signature:\n"
" compress(string, mode=MODE_GENERIC, quality=11, lgwin=22, lgblock=0, dictionary='')\n"
"\n"
"Args:\n"
" string (bytes): The input data.\n"
" mode (int, optional): The compression mode can be MODE_GENERIC (default),\n"
" MODE_TEXT (for UTF-8 format text input) or MODE_FONT (for WOFF 2.0). \n"
" quality (int, optional): Controls the compression-speed vs compression-\n"
" density tradeoff. The higher the quality, the slower the compression.\n"
" Range is 0 to 11. Defaults to 11.\n"
" lgwin (int, optional): Base 2 logarithm of the sliding window size. Range\n"
" is 10 to 24. Defaults to 22.\n"
" lgblock (int, optional): Base 2 logarithm of the maximum input block size.\n"
" Range is 16 to 24. If set to 0, the value will be set based on the\n"
" quality. Defaults to 0.\n"
" dictionary (bytes, optional): Custom dictionary. Only last sliding window\n"
" size bytes will be used.\n"
"\n"
"Returns:\n"
" The compressed byte string.\n"
"\n"
"Raises:\n"
" brotli.error: If arguments are invalid, or compressor fails.\n");
static PyObject* brotli_compress(PyObject *self, PyObject *args, PyObject *keywds) {
PyObject *ret = NULL;
uint8_t *input, *output = NULL, *custom_dictionary, *next_out;
const uint8_t *next_in;
size_t length, output_length, custom_dictionary_length, available_in, available_out;
BrotliEncoderMode mode = (BrotliEncoderMode) -1;
int quality = -1;
int lgwin = -1;
int lgblock = -1;
int ok;
static const char *kwlist[] = {
"string", "mode", "quality", "lgwin", "lgblock", "dictionary", NULL};
custom_dictionary = NULL;
custom_dictionary_length = 0;
ok = PyArg_ParseTupleAndKeywords(args, keywds, "s#|O&O&O&O&s#:compress",
const_cast<char **>(kwlist),
&input, &length,
&mode_convertor, &mode,
&quality_convertor, &quality,
&lgwin_convertor, &lgwin,
&lgblock_convertor, &lgblock,
&custom_dictionary, &custom_dictionary_length);
if (!ok)
return NULL;
output_length = length + (length >> 2) + 10240;
BrotliEncoderState* enc = BrotliEncoderCreateInstance(0, 0, 0);
if (!enc) {
ok = false;
goto end;
}
output = new uint8_t[output_length];
if ((int) mode != -1)
BrotliEncoderSetParameter(enc, BROTLI_PARAM_MODE, (uint32_t)mode);
if (quality != -1)
BrotliEncoderSetParameter(enc, BROTLI_PARAM_QUALITY, (uint32_t)quality);
if (lgwin != -1)
BrotliEncoderSetParameter(enc, BROTLI_PARAM_LGWIN, (uint32_t)lgwin);
if (lgblock != -1)
BrotliEncoderSetParameter(enc, BROTLI_PARAM_LGBLOCK, (uint32_t)lgblock);
if (custom_dictionary_length != 0) {
BrotliEncoderSetCustomDictionary(enc, custom_dictionary_length,
custom_dictionary);
}
available_out = output_length;
next_out = output;
available_in = length;
next_in = input;
BrotliEncoderCompressStream(enc, BROTLI_OPERATION_FINISH,
&available_in, &next_in,
&available_out, &next_out, 0);
ok = BrotliEncoderIsFinished(enc);
end:
BrotliEncoderDestroyInstance(enc);
if (ok) {
ret = PyBytes_FromStringAndSize((char*)output, output_length - available_out);
} else {
PyErr_SetString(BrotliError, "BrotliCompressBuffer failed");
}
delete[] output;
return ret;
}
PyDoc_STRVAR(decompress__doc__,
"Decompress a compressed byte string.\n"
"\n"
"Signature:\n"
" decompress(string)\n"
"\n"
"Args:\n"
" string (bytes): The compressed input data.\n"
" dictionary (bytes, optional): Custom dictionary. MUST be the same data\n"
" as passed to compress method.\n"
"\n"
"Returns:\n"
" The decompressed byte string.\n"
"\n"
"Raises:\n"
" brotli.error: If decompressor fails.\n");
static PyObject* brotli_decompress(PyObject *self, PyObject *args, PyObject *keywds) {
PyObject *ret = NULL;
const uint8_t *input, *custom_dictionary;
size_t length, custom_dictionary_length;
int ok;
static const char *kwlist[] = {"string", "dictionary", NULL};
custom_dictionary = NULL;
custom_dictionary_length = 0;
ok = PyArg_ParseTupleAndKeywords(args, keywds, "s#|s#:decompress",
const_cast<char **>(kwlist),
&input, &length,
&custom_dictionary, &custom_dictionary_length);
if (!ok)
return NULL;
std::vector<uint8_t> output;
const size_t kBufferSize = 65536;
uint8_t* buffer = new uint8_t[kBufferSize];
BrotliState* state = BrotliCreateState(0, 0, 0);
if (custom_dictionary_length != 0) {
BrotliSetCustomDictionary(custom_dictionary_length, custom_dictionary, state);
}
BrotliResult result = BROTLI_RESULT_NEEDS_MORE_OUTPUT;
while (result == BROTLI_RESULT_NEEDS_MORE_OUTPUT) {
size_t available_out = kBufferSize;
uint8_t* next_out = buffer;
size_t total_out = 0;
result = BrotliDecompressStream(&length, &input,
&available_out, &next_out,
&total_out, state);
size_t used_out = kBufferSize - available_out;
if (used_out != 0)
output.insert(output.end(), buffer, buffer + used_out);
}
ok = result == BROTLI_RESULT_SUCCESS;
if (ok) {
ret = PyBytes_FromStringAndSize((char*)(output.size() ? &output[0] : NULL), output.size());
} else {
PyErr_SetString(BrotliError, "BrotliDecompress failed");
}
BrotliDestroyState(state);
delete[] buffer;
return ret;
}
static PyMethodDef brotli_methods[] = {
{"compress", (PyCFunction)brotli_compress, METH_VARARGS | METH_KEYWORDS, compress__doc__},
{"decompress", (PyCFunction)brotli_decompress, METH_VARARGS | METH_KEYWORDS, decompress__doc__},
{NULL, NULL, 0, NULL}
};
PyDoc_STRVAR(brotli__doc__,
"The functions in this module allow compression and decompression using the\n"
"Brotli library.\n\n");
#if PY_MAJOR_VERSION >= 3
#define INIT_BROTLI PyInit_brotli
#define CREATE_BROTLI PyModule_Create(&brotli_module)
#define RETURN_BROTLI return m
static struct PyModuleDef brotli_module = {
PyModuleDef_HEAD_INIT,
"brotli",
brotli__doc__,
0,
brotli_methods,
NULL,
NULL,
NULL
};
#else
#define INIT_BROTLI initbrotli
#define CREATE_BROTLI Py_InitModule3("brotli", brotli_methods, brotli__doc__)
#define RETURN_BROTLI return
#endif
PyMODINIT_FUNC INIT_BROTLI(void) {
PyObject *m = CREATE_BROTLI;
BrotliError = PyErr_NewException((char*) "brotli.error", NULL, NULL);
if (BrotliError != NULL) {
Py_INCREF(BrotliError);
PyModule_AddObject(m, "error", BrotliError);
}
PyModule_AddIntConstant(m, "MODE_GENERIC", (int) BROTLI_MODE_GENERIC);
PyModule_AddIntConstant(m, "MODE_TEXT", (int) BROTLI_MODE_TEXT);
PyModule_AddIntConstant(m, "MODE_FONT", (int) BROTLI_MODE_FONT);
PyModule_AddStringConstant(m, "__version__", BROTLI_VERSION);
RETURN_BROTLI;
}