1093 lines
32 KiB
C
1093 lines
32 KiB
C
/* zlibmodule.c -- gzip-compatible data compression */
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/* See http://www.gzip.org/zlib/ */
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/* Windows users: read Python's PCbuild\readme.txt */
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#include "Python.h"
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#include "zlib.h"
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#ifdef WITH_THREAD
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#include "pythread.h"
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/* #defs ripped off from _tkinter.c, even though the situation here is much
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simpler, because we don't have to worry about waiting for Tcl
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events! And, since zlib itself is threadsafe, we don't need to worry
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about re-entering zlib functions.
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N.B.
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Since ENTER_ZLIB and LEAVE_ZLIB only need to be called on functions
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that modify the components of preexisting de/compress objects, it
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could prove to be a performance gain on multiprocessor machines if
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there was an de/compress object-specific lock. However, for the
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moment the ENTER_ZLIB and LEAVE_ZLIB calls are global for ALL
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de/compress objects.
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*/
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static PyThread_type_lock zlib_lock = NULL; /* initialized on module load */
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#define ENTER_ZLIB \
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Py_BEGIN_ALLOW_THREADS \
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PyThread_acquire_lock(zlib_lock, 1); \
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Py_END_ALLOW_THREADS
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#define LEAVE_ZLIB \
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PyThread_release_lock(zlib_lock);
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#else
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#define ENTER_ZLIB
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#define LEAVE_ZLIB
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#endif
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/* The following parameters are copied from zutil.h, version 0.95 */
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#define DEFLATED 8
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#if MAX_MEM_LEVEL >= 8
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# define DEF_MEM_LEVEL 8
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#else
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# define DEF_MEM_LEVEL MAX_MEM_LEVEL
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#endif
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#define DEF_WBITS MAX_WBITS
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/* The output buffer will be increased in chunks of DEFAULTALLOC bytes. */
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#define DEFAULTALLOC (16*1024)
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#define PyInit_zlib initzlib
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static PyTypeObject Comptype;
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static PyTypeObject Decomptype;
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static PyObject *ZlibError;
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typedef struct
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{
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PyObject_HEAD
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z_stream zst;
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PyObject *unused_data;
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PyObject *unconsumed_tail;
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int is_initialised;
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} compobject;
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static void
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zlib_error(z_stream zst, int err, char *msg)
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{
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const char *zmsg = Z_NULL;
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/* In case of a version mismatch, zst.msg won't be initialized.
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Check for this case first, before looking at zst.msg. */
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if (err == Z_VERSION_ERROR)
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zmsg = "library version mismatch";
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if (zmsg == Z_NULL)
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zmsg = zst.msg;
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if (zmsg == Z_NULL) {
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switch (err) {
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case Z_BUF_ERROR:
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zmsg = "incomplete or truncated stream";
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break;
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case Z_STREAM_ERROR:
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zmsg = "inconsistent stream state";
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break;
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case Z_DATA_ERROR:
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zmsg = "invalid input data";
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break;
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}
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}
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if (zmsg == Z_NULL)
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PyErr_Format(ZlibError, "Error %d %s", err, msg);
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else
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PyErr_Format(ZlibError, "Error %d %s: %.200s", err, msg, zmsg);
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}
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PyDoc_STRVAR(compressobj__doc__,
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"compressobj([level]) -- Return a compressor object.\n"
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"\n"
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"Optional arg level is the compression level, in 0-9.");
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PyDoc_STRVAR(decompressobj__doc__,
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"decompressobj([wbits]) -- Return a decompressor object.\n"
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"\n"
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"Optional arg wbits is the window buffer size.");
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static compobject *
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newcompobject(PyTypeObject *type)
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{
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compobject *self;
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self = PyObject_New(compobject, type);
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if (self == NULL)
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return NULL;
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self->is_initialised = 0;
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self->unused_data = PyString_FromString("");
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if (self->unused_data == NULL) {
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Py_DECREF(self);
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return NULL;
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}
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self->unconsumed_tail = PyString_FromString("");
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if (self->unconsumed_tail == NULL) {
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Py_DECREF(self);
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return NULL;
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}
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return self;
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}
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PyDoc_STRVAR(compress__doc__,
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"compress(string[, level]) -- Returned compressed string.\n"
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"\n"
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"Optional arg level is the compression level, in 0-9.");
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static PyObject *
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PyZlib_compress(PyObject *self, PyObject *args)
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{
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PyObject *ReturnVal = NULL;
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Byte *input, *output;
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int length, level=Z_DEFAULT_COMPRESSION, err;
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z_stream zst;
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/* require Python string object, optional 'level' arg */
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if (!PyArg_ParseTuple(args, "s#|i:compress", &input, &length, &level))
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return NULL;
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zst.avail_out = length + length/1000 + 12 + 1;
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output = (Byte*)malloc(zst.avail_out);
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if (output == NULL) {
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PyErr_SetString(PyExc_MemoryError,
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"Can't allocate memory to compress data");
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return NULL;
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}
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/* Past the point of no return. From here on out, we need to make sure
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we clean up mallocs & INCREFs. */
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zst.zalloc = (alloc_func)NULL;
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zst.zfree = (free_func)Z_NULL;
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zst.next_out = (Byte *)output;
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zst.next_in = (Byte *)input;
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zst.avail_in = length;
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err = deflateInit(&zst, level);
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switch(err) {
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case(Z_OK):
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break;
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case(Z_MEM_ERROR):
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PyErr_SetString(PyExc_MemoryError,
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"Out of memory while compressing data");
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goto error;
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case(Z_STREAM_ERROR):
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PyErr_SetString(ZlibError,
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"Bad compression level");
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goto error;
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default:
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deflateEnd(&zst);
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zlib_error(zst, err, "while compressing data");
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goto error;
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}
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Py_BEGIN_ALLOW_THREADS;
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err = deflate(&zst, Z_FINISH);
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Py_END_ALLOW_THREADS;
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if (err != Z_STREAM_END) {
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zlib_error(zst, err, "while compressing data");
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deflateEnd(&zst);
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goto error;
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}
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err=deflateEnd(&zst);
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if (err == Z_OK)
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ReturnVal = PyString_FromStringAndSize((char *)output,
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zst.total_out);
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else
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zlib_error(zst, err, "while finishing compression");
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error:
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free(output);
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return ReturnVal;
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}
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PyDoc_STRVAR(decompress__doc__,
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"decompress(string[, wbits[, bufsize]]) -- Return decompressed string.\n"
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"\n"
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"Optional arg wbits is the window buffer size. Optional arg bufsize is\n"
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"the initial output buffer size.");
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static PyObject *
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PyZlib_decompress(PyObject *self, PyObject *args)
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{
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PyObject *result_str;
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Byte *input;
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int length, err;
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int wsize=DEF_WBITS;
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Py_ssize_t r_strlen=DEFAULTALLOC;
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z_stream zst;
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if (!PyArg_ParseTuple(args, "s#|in:decompress",
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&input, &length, &wsize, &r_strlen))
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return NULL;
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if (r_strlen <= 0)
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r_strlen = 1;
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zst.avail_in = length;
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zst.avail_out = r_strlen;
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if (!(result_str = PyString_FromStringAndSize(NULL, r_strlen)))
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return NULL;
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zst.zalloc = (alloc_func)NULL;
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zst.zfree = (free_func)Z_NULL;
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zst.next_out = (Byte *)PyString_AS_STRING(result_str);
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zst.next_in = (Byte *)input;
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err = inflateInit2(&zst, wsize);
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switch(err) {
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case(Z_OK):
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break;
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case(Z_MEM_ERROR):
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PyErr_SetString(PyExc_MemoryError,
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"Out of memory while decompressing data");
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goto error;
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default:
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inflateEnd(&zst);
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zlib_error(zst, err, "while preparing to decompress data");
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goto error;
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}
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do {
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Py_BEGIN_ALLOW_THREADS
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err=inflate(&zst, Z_FINISH);
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Py_END_ALLOW_THREADS
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switch(err) {
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case(Z_STREAM_END):
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break;
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case(Z_BUF_ERROR):
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/*
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* If there is at least 1 byte of room according to zst.avail_out
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* and we get this error, assume that it means zlib cannot
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* process the inflate call() due to an error in the data.
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*/
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if (zst.avail_out > 0) {
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zlib_error(zst, err, "while decompressing data");
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inflateEnd(&zst);
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goto error;
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}
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/* fall through */
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case(Z_OK):
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/* need more memory */
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if (_PyString_Resize(&result_str, r_strlen << 1) < 0) {
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inflateEnd(&zst);
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goto error;
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}
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zst.next_out = (unsigned char *)PyString_AS_STRING(result_str) \
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+ r_strlen;
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zst.avail_out = r_strlen;
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r_strlen = r_strlen << 1;
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break;
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default:
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inflateEnd(&zst);
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zlib_error(zst, err, "while decompressing data");
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goto error;
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}
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} while (err != Z_STREAM_END);
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err = inflateEnd(&zst);
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if (err != Z_OK) {
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zlib_error(zst, err, "while finishing data decompression");
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goto error;
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}
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_PyString_Resize(&result_str, zst.total_out);
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return result_str;
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error:
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Py_XDECREF(result_str);
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return NULL;
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}
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static PyObject *
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PyZlib_compressobj(PyObject *selfptr, PyObject *args)
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{
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compobject *self;
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int level=Z_DEFAULT_COMPRESSION, method=DEFLATED;
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int wbits=MAX_WBITS, memLevel=DEF_MEM_LEVEL, strategy=0, err;
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if (!PyArg_ParseTuple(args, "|iiiii:compressobj", &level, &method, &wbits,
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&memLevel, &strategy))
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return NULL;
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self = newcompobject(&Comptype);
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if (self==NULL)
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return(NULL);
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self->zst.zalloc = (alloc_func)NULL;
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self->zst.zfree = (free_func)Z_NULL;
|
|
self->zst.next_in = NULL;
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self->zst.avail_in = 0;
|
|
err = deflateInit2(&self->zst, level, method, wbits, memLevel, strategy);
|
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switch(err) {
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|
case (Z_OK):
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|
self->is_initialised = 1;
|
|
return (PyObject*)self;
|
|
case (Z_MEM_ERROR):
|
|
Py_DECREF(self);
|
|
PyErr_SetString(PyExc_MemoryError,
|
|
"Can't allocate memory for compression object");
|
|
return NULL;
|
|
case(Z_STREAM_ERROR):
|
|
Py_DECREF(self);
|
|
PyErr_SetString(PyExc_ValueError, "Invalid initialization option");
|
|
return NULL;
|
|
default:
|
|
zlib_error(self->zst, err, "while creating compression object");
|
|
Py_DECREF(self);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static PyObject *
|
|
PyZlib_decompressobj(PyObject *selfptr, PyObject *args)
|
|
{
|
|
int wbits=DEF_WBITS, err;
|
|
compobject *self;
|
|
if (!PyArg_ParseTuple(args, "|i:decompressobj", &wbits))
|
|
return NULL;
|
|
|
|
self = newcompobject(&Decomptype);
|
|
if (self == NULL)
|
|
return(NULL);
|
|
self->zst.zalloc = (alloc_func)NULL;
|
|
self->zst.zfree = (free_func)Z_NULL;
|
|
self->zst.next_in = NULL;
|
|
self->zst.avail_in = 0;
|
|
err = inflateInit2(&self->zst, wbits);
|
|
switch(err) {
|
|
case (Z_OK):
|
|
self->is_initialised = 1;
|
|
return (PyObject*)self;
|
|
case(Z_STREAM_ERROR):
|
|
Py_DECREF(self);
|
|
PyErr_SetString(PyExc_ValueError, "Invalid initialization option");
|
|
return NULL;
|
|
case (Z_MEM_ERROR):
|
|
Py_DECREF(self);
|
|
PyErr_SetString(PyExc_MemoryError,
|
|
"Can't allocate memory for decompression object");
|
|
return NULL;
|
|
default:
|
|
zlib_error(self->zst, err, "while creating decompression object");
|
|
Py_DECREF(self);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static void
|
|
Comp_dealloc(compobject *self)
|
|
{
|
|
if (self->is_initialised)
|
|
deflateEnd(&self->zst);
|
|
Py_XDECREF(self->unused_data);
|
|
Py_XDECREF(self->unconsumed_tail);
|
|
PyObject_Del(self);
|
|
}
|
|
|
|
static void
|
|
Decomp_dealloc(compobject *self)
|
|
{
|
|
if (self->is_initialised)
|
|
inflateEnd(&self->zst);
|
|
Py_XDECREF(self->unused_data);
|
|
Py_XDECREF(self->unconsumed_tail);
|
|
PyObject_Del(self);
|
|
}
|
|
|
|
PyDoc_STRVAR(comp_compress__doc__,
|
|
"compress(data) -- Return a string containing data compressed.\n"
|
|
"\n"
|
|
"After calling this function, some of the input data may still\n"
|
|
"be stored in internal buffers for later processing.\n"
|
|
"Call the flush() method to clear these buffers.");
|
|
|
|
|
|
static PyObject *
|
|
PyZlib_objcompress(compobject *self, PyObject *args)
|
|
{
|
|
int err, inplen;
|
|
Py_ssize_t length = DEFAULTALLOC;
|
|
PyObject *RetVal;
|
|
Byte *input;
|
|
unsigned long start_total_out;
|
|
|
|
if (!PyArg_ParseTuple(args, "s#:compress", &input, &inplen))
|
|
return NULL;
|
|
|
|
if (!(RetVal = PyString_FromStringAndSize(NULL, length)))
|
|
return NULL;
|
|
|
|
ENTER_ZLIB
|
|
|
|
start_total_out = self->zst.total_out;
|
|
self->zst.avail_in = inplen;
|
|
self->zst.next_in = input;
|
|
self->zst.avail_out = length;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal);
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = deflate(&(self->zst), Z_NO_FLUSH);
|
|
Py_END_ALLOW_THREADS
|
|
|
|
/* while Z_OK and the output buffer is full, there might be more output,
|
|
so extend the output buffer and try again */
|
|
while (err == Z_OK && self->zst.avail_out == 0) {
|
|
if (_PyString_Resize(&RetVal, length << 1) < 0)
|
|
goto error;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal) \
|
|
+ length;
|
|
self->zst.avail_out = length;
|
|
length = length << 1;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = deflate(&(self->zst), Z_NO_FLUSH);
|
|
Py_END_ALLOW_THREADS
|
|
}
|
|
/* We will only get Z_BUF_ERROR if the output buffer was full but
|
|
there wasn't more output when we tried again, so it is not an error
|
|
condition.
|
|
*/
|
|
|
|
if (err != Z_OK && err != Z_BUF_ERROR) {
|
|
zlib_error(self->zst, err, "while compressing");
|
|
Py_DECREF(RetVal);
|
|
RetVal = NULL;
|
|
goto error;
|
|
}
|
|
_PyString_Resize(&RetVal, self->zst.total_out - start_total_out);
|
|
|
|
error:
|
|
LEAVE_ZLIB
|
|
return RetVal;
|
|
}
|
|
|
|
/* Helper for objdecompress() and unflush(). Saves any unconsumed input data in
|
|
self->unused_data or self->unconsumed_tail, as appropriate. */
|
|
static int
|
|
save_unconsumed_input(compobject *self, int err)
|
|
{
|
|
if (err == Z_STREAM_END) {
|
|
/* The end of the compressed data has been reached. Store the leftover
|
|
input data in self->unused_data. */
|
|
if (self->zst.avail_in > 0) {
|
|
Py_ssize_t old_size = PyString_GET_SIZE(self->unused_data);
|
|
Py_ssize_t new_size;
|
|
PyObject *new_data;
|
|
if (self->zst.avail_in > PY_SSIZE_T_MAX - old_size) {
|
|
PyErr_NoMemory();
|
|
return -1;
|
|
}
|
|
new_size = old_size + self->zst.avail_in;
|
|
new_data = PyString_FromStringAndSize(NULL, new_size);
|
|
if (new_data == NULL)
|
|
return -1;
|
|
Py_MEMCPY(PyString_AS_STRING(new_data),
|
|
PyString_AS_STRING(self->unused_data), old_size);
|
|
Py_MEMCPY(PyString_AS_STRING(new_data) + old_size,
|
|
self->zst.next_in, self->zst.avail_in);
|
|
Py_DECREF(self->unused_data);
|
|
self->unused_data = new_data;
|
|
self->zst.avail_in = 0;
|
|
}
|
|
}
|
|
if (self->zst.avail_in > 0 || PyString_GET_SIZE(self->unconsumed_tail)) {
|
|
/* This code handles two distinct cases:
|
|
1. Output limit was reached. Save leftover input in unconsumed_tail.
|
|
2. All input data was consumed. Clear unconsumed_tail. */
|
|
PyObject *new_data = PyString_FromStringAndSize(
|
|
(char *)self->zst.next_in, self->zst.avail_in);
|
|
if (new_data == NULL)
|
|
return -1;
|
|
Py_DECREF(self->unconsumed_tail);
|
|
self->unconsumed_tail = new_data;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
PyDoc_STRVAR(decomp_decompress__doc__,
|
|
"decompress(data, max_length) -- Return a string containing the decompressed\n"
|
|
"version of the data.\n"
|
|
"\n"
|
|
"After calling this function, some of the input data may still be stored in\n"
|
|
"internal buffers for later processing.\n"
|
|
"Call the flush() method to clear these buffers.\n"
|
|
"If the max_length parameter is specified then the return value will be\n"
|
|
"no longer than max_length. Unconsumed input data will be stored in\n"
|
|
"the unconsumed_tail attribute.");
|
|
|
|
static PyObject *
|
|
PyZlib_objdecompress(compobject *self, PyObject *args)
|
|
{
|
|
int err, inplen, max_length = 0;
|
|
Py_ssize_t old_length, length = DEFAULTALLOC;
|
|
PyObject *RetVal;
|
|
Byte *input;
|
|
unsigned long start_total_out;
|
|
|
|
if (!PyArg_ParseTuple(args, "s#|i:decompress", &input,
|
|
&inplen, &max_length))
|
|
return NULL;
|
|
if (max_length < 0) {
|
|
PyErr_SetString(PyExc_ValueError,
|
|
"max_length must be greater than zero");
|
|
return NULL;
|
|
}
|
|
|
|
/* limit amount of data allocated to max_length */
|
|
if (max_length && length > max_length)
|
|
length = max_length;
|
|
if (!(RetVal = PyString_FromStringAndSize(NULL, length)))
|
|
return NULL;
|
|
|
|
ENTER_ZLIB
|
|
|
|
start_total_out = self->zst.total_out;
|
|
self->zst.avail_in = inplen;
|
|
self->zst.next_in = input;
|
|
self->zst.avail_out = length;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal);
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = inflate(&(self->zst), Z_SYNC_FLUSH);
|
|
Py_END_ALLOW_THREADS
|
|
|
|
/* While Z_OK and the output buffer is full, there might be more output.
|
|
So extend the output buffer and try again.
|
|
*/
|
|
while (err == Z_OK && self->zst.avail_out == 0) {
|
|
/* If max_length set, don't continue decompressing if we've already
|
|
reached the limit.
|
|
*/
|
|
if (max_length && length >= max_length)
|
|
break;
|
|
|
|
/* otherwise, ... */
|
|
old_length = length;
|
|
length = length << 1;
|
|
if (max_length && length > max_length)
|
|
length = max_length;
|
|
|
|
if (_PyString_Resize(&RetVal, length) < 0)
|
|
goto error;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal) \
|
|
+ old_length;
|
|
self->zst.avail_out = length - old_length;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = inflate(&(self->zst), Z_SYNC_FLUSH);
|
|
Py_END_ALLOW_THREADS
|
|
}
|
|
|
|
if (save_unconsumed_input(self, err) < 0) {
|
|
Py_DECREF(RetVal);
|
|
RetVal = NULL;
|
|
goto error;
|
|
}
|
|
|
|
/* This is the logical place to call inflateEnd, but the old behaviour of
|
|
only calling it on flush() is preserved. */
|
|
|
|
if (err != Z_STREAM_END && err != Z_OK && err != Z_BUF_ERROR) {
|
|
/* We will only get Z_BUF_ERROR if the output buffer was full
|
|
but there wasn't more output when we tried again, so it is
|
|
not an error condition.
|
|
*/
|
|
zlib_error(self->zst, err, "while decompressing");
|
|
Py_DECREF(RetVal);
|
|
RetVal = NULL;
|
|
goto error;
|
|
}
|
|
|
|
_PyString_Resize(&RetVal, self->zst.total_out - start_total_out);
|
|
|
|
error:
|
|
LEAVE_ZLIB
|
|
|
|
return RetVal;
|
|
}
|
|
|
|
PyDoc_STRVAR(comp_flush__doc__,
|
|
"flush( [mode] ) -- Return a string containing any remaining compressed data.\n"
|
|
"\n"
|
|
"mode can be one of the constants Z_SYNC_FLUSH, Z_FULL_FLUSH, Z_FINISH; the\n"
|
|
"default value used when mode is not specified is Z_FINISH.\n"
|
|
"If mode == Z_FINISH, the compressor object can no longer be used after\n"
|
|
"calling the flush() method. Otherwise, more data can still be compressed.");
|
|
|
|
static PyObject *
|
|
PyZlib_flush(compobject *self, PyObject *args)
|
|
{
|
|
int err, length = DEFAULTALLOC;
|
|
PyObject *RetVal;
|
|
int flushmode = Z_FINISH;
|
|
unsigned long start_total_out;
|
|
|
|
if (!PyArg_ParseTuple(args, "|i:flush", &flushmode))
|
|
return NULL;
|
|
|
|
/* Flushing with Z_NO_FLUSH is a no-op, so there's no point in
|
|
doing any work at all; just return an empty string. */
|
|
if (flushmode == Z_NO_FLUSH) {
|
|
return PyString_FromStringAndSize(NULL, 0);
|
|
}
|
|
|
|
if (!(RetVal = PyString_FromStringAndSize(NULL, length)))
|
|
return NULL;
|
|
|
|
ENTER_ZLIB
|
|
|
|
start_total_out = self->zst.total_out;
|
|
self->zst.avail_in = 0;
|
|
self->zst.avail_out = length;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal);
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = deflate(&(self->zst), flushmode);
|
|
Py_END_ALLOW_THREADS
|
|
|
|
/* while Z_OK and the output buffer is full, there might be more output,
|
|
so extend the output buffer and try again */
|
|
while (err == Z_OK && self->zst.avail_out == 0) {
|
|
if (_PyString_Resize(&RetVal, length << 1) < 0)
|
|
goto error;
|
|
self->zst.next_out = (unsigned char *)PyString_AS_STRING(RetVal) \
|
|
+ length;
|
|
self->zst.avail_out = length;
|
|
length = length << 1;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = deflate(&(self->zst), flushmode);
|
|
Py_END_ALLOW_THREADS
|
|
}
|
|
|
|
/* If flushmode is Z_FINISH, we also have to call deflateEnd() to free
|
|
various data structures. Note we should only get Z_STREAM_END when
|
|
flushmode is Z_FINISH, but checking both for safety*/
|
|
if (err == Z_STREAM_END && flushmode == Z_FINISH) {
|
|
err = deflateEnd(&(self->zst));
|
|
if (err != Z_OK) {
|
|
zlib_error(self->zst, err, "from deflateEnd()");
|
|
Py_DECREF(RetVal);
|
|
RetVal = NULL;
|
|
goto error;
|
|
}
|
|
else
|
|
self->is_initialised = 0;
|
|
|
|
/* We will only get Z_BUF_ERROR if the output buffer was full
|
|
but there wasn't more output when we tried again, so it is
|
|
not an error condition.
|
|
*/
|
|
} else if (err!=Z_OK && err!=Z_BUF_ERROR) {
|
|
zlib_error(self->zst, err, "while flushing");
|
|
Py_DECREF(RetVal);
|
|
RetVal = NULL;
|
|
goto error;
|
|
}
|
|
|
|
_PyString_Resize(&RetVal, self->zst.total_out - start_total_out);
|
|
|
|
error:
|
|
LEAVE_ZLIB
|
|
|
|
return RetVal;
|
|
}
|
|
|
|
#ifdef HAVE_ZLIB_COPY
|
|
PyDoc_STRVAR(comp_copy__doc__,
|
|
"copy() -- Return a copy of the compression object.");
|
|
|
|
static PyObject *
|
|
PyZlib_copy(compobject *self)
|
|
{
|
|
compobject *retval = NULL;
|
|
int err;
|
|
|
|
retval = newcompobject(&Comptype);
|
|
if (!retval) return NULL;
|
|
|
|
/* Copy the zstream state
|
|
* We use ENTER_ZLIB / LEAVE_ZLIB to make this thread-safe
|
|
*/
|
|
ENTER_ZLIB
|
|
err = deflateCopy(&retval->zst, &self->zst);
|
|
switch(err) {
|
|
case(Z_OK):
|
|
break;
|
|
case(Z_STREAM_ERROR):
|
|
PyErr_SetString(PyExc_ValueError, "Inconsistent stream state");
|
|
goto error;
|
|
case(Z_MEM_ERROR):
|
|
PyErr_SetString(PyExc_MemoryError,
|
|
"Can't allocate memory for compression object");
|
|
goto error;
|
|
default:
|
|
zlib_error(self->zst, err, "while copying compression object");
|
|
goto error;
|
|
}
|
|
|
|
Py_INCREF(self->unused_data);
|
|
Py_INCREF(self->unconsumed_tail);
|
|
Py_XDECREF(retval->unused_data);
|
|
Py_XDECREF(retval->unconsumed_tail);
|
|
retval->unused_data = self->unused_data;
|
|
retval->unconsumed_tail = self->unconsumed_tail;
|
|
|
|
/* Mark it as being initialized */
|
|
retval->is_initialised = 1;
|
|
|
|
LEAVE_ZLIB
|
|
return (PyObject *)retval;
|
|
|
|
error:
|
|
LEAVE_ZLIB
|
|
Py_XDECREF(retval);
|
|
return NULL;
|
|
}
|
|
|
|
PyDoc_STRVAR(decomp_copy__doc__,
|
|
"copy() -- Return a copy of the decompression object.");
|
|
|
|
static PyObject *
|
|
PyZlib_uncopy(compobject *self)
|
|
{
|
|
compobject *retval = NULL;
|
|
int err;
|
|
|
|
retval = newcompobject(&Decomptype);
|
|
if (!retval) return NULL;
|
|
|
|
/* Copy the zstream state
|
|
* We use ENTER_ZLIB / LEAVE_ZLIB to make this thread-safe
|
|
*/
|
|
ENTER_ZLIB
|
|
err = inflateCopy(&retval->zst, &self->zst);
|
|
switch(err) {
|
|
case(Z_OK):
|
|
break;
|
|
case(Z_STREAM_ERROR):
|
|
PyErr_SetString(PyExc_ValueError, "Inconsistent stream state");
|
|
goto error;
|
|
case(Z_MEM_ERROR):
|
|
PyErr_SetString(PyExc_MemoryError,
|
|
"Can't allocate memory for decompression object");
|
|
goto error;
|
|
default:
|
|
zlib_error(self->zst, err, "while copying decompression object");
|
|
goto error;
|
|
}
|
|
|
|
Py_INCREF(self->unused_data);
|
|
Py_INCREF(self->unconsumed_tail);
|
|
Py_XDECREF(retval->unused_data);
|
|
Py_XDECREF(retval->unconsumed_tail);
|
|
retval->unused_data = self->unused_data;
|
|
retval->unconsumed_tail = self->unconsumed_tail;
|
|
|
|
/* Mark it as being initialized */
|
|
retval->is_initialised = 1;
|
|
|
|
LEAVE_ZLIB
|
|
return (PyObject *)retval;
|
|
|
|
error:
|
|
LEAVE_ZLIB
|
|
Py_XDECREF(retval);
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
PyDoc_STRVAR(decomp_flush__doc__,
|
|
"flush( [length] ) -- Return a string containing any remaining\n"
|
|
"decompressed data. length, if given, is the initial size of the\n"
|
|
"output buffer.\n"
|
|
"\n"
|
|
"The decompressor object can no longer be used after this call.");
|
|
|
|
static PyObject *
|
|
PyZlib_unflush(compobject *self, PyObject *args)
|
|
{
|
|
int err, length = DEFAULTALLOC;
|
|
PyObject * retval = NULL;
|
|
unsigned long start_total_out;
|
|
|
|
if (!PyArg_ParseTuple(args, "|i:flush", &length))
|
|
return NULL;
|
|
if (length <= 0) {
|
|
PyErr_SetString(PyExc_ValueError, "length must be greater than zero");
|
|
return NULL;
|
|
}
|
|
if (!(retval = PyString_FromStringAndSize(NULL, length)))
|
|
return NULL;
|
|
|
|
|
|
ENTER_ZLIB
|
|
|
|
start_total_out = self->zst.total_out;
|
|
self->zst.avail_in = PyString_GET_SIZE(self->unconsumed_tail);
|
|
self->zst.next_in = (Byte *)PyString_AS_STRING(self->unconsumed_tail);
|
|
self->zst.avail_out = length;
|
|
self->zst.next_out = (Byte *)PyString_AS_STRING(retval);
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = inflate(&(self->zst), Z_FINISH);
|
|
Py_END_ALLOW_THREADS
|
|
|
|
/* while Z_OK and the output buffer is full, there might be more output,
|
|
so extend the output buffer and try again */
|
|
while ((err == Z_OK || err == Z_BUF_ERROR) && self->zst.avail_out == 0) {
|
|
if (_PyString_Resize(&retval, length << 1) < 0)
|
|
goto error;
|
|
self->zst.next_out = (Byte *)PyString_AS_STRING(retval) + length;
|
|
self->zst.avail_out = length;
|
|
length = length << 1;
|
|
|
|
Py_BEGIN_ALLOW_THREADS
|
|
err = inflate(&(self->zst), Z_FINISH);
|
|
Py_END_ALLOW_THREADS
|
|
}
|
|
|
|
if (save_unconsumed_input(self, err) < 0) {
|
|
Py_DECREF(retval);
|
|
retval = NULL;
|
|
goto error;
|
|
}
|
|
|
|
/* If flushmode is Z_FINISH, we also have to call deflateEnd() to free
|
|
various data structures. Note we should only get Z_STREAM_END when
|
|
flushmode is Z_FINISH */
|
|
if (err == Z_STREAM_END) {
|
|
err = inflateEnd(&(self->zst));
|
|
self->is_initialised = 0;
|
|
if (err != Z_OK) {
|
|
zlib_error(self->zst, err, "from inflateEnd()");
|
|
Py_DECREF(retval);
|
|
retval = NULL;
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
_PyString_Resize(&retval, self->zst.total_out - start_total_out);
|
|
|
|
error:
|
|
|
|
LEAVE_ZLIB
|
|
|
|
return retval;
|
|
}
|
|
|
|
static PyMethodDef comp_methods[] =
|
|
{
|
|
{"compress", (binaryfunc)PyZlib_objcompress, METH_VARARGS,
|
|
comp_compress__doc__},
|
|
{"flush", (binaryfunc)PyZlib_flush, METH_VARARGS,
|
|
comp_flush__doc__},
|
|
#ifdef HAVE_ZLIB_COPY
|
|
{"copy", (PyCFunction)PyZlib_copy, METH_NOARGS,
|
|
comp_copy__doc__},
|
|
#endif
|
|
{NULL, NULL}
|
|
};
|
|
|
|
static PyMethodDef Decomp_methods[] =
|
|
{
|
|
{"decompress", (binaryfunc)PyZlib_objdecompress, METH_VARARGS,
|
|
decomp_decompress__doc__},
|
|
{"flush", (binaryfunc)PyZlib_unflush, METH_VARARGS,
|
|
decomp_flush__doc__},
|
|
#ifdef HAVE_ZLIB_COPY
|
|
{"copy", (PyCFunction)PyZlib_uncopy, METH_NOARGS,
|
|
decomp_copy__doc__},
|
|
#endif
|
|
{NULL, NULL}
|
|
};
|
|
|
|
static PyObject *
|
|
Comp_getattr(compobject *self, char *name)
|
|
{
|
|
/* No ENTER/LEAVE_ZLIB is necessary because this fn doesn't touch
|
|
internal data. */
|
|
|
|
return Py_FindMethod(comp_methods, (PyObject *)self, name);
|
|
}
|
|
|
|
static PyObject *
|
|
Decomp_getattr(compobject *self, char *name)
|
|
{
|
|
PyObject * retval;
|
|
|
|
ENTER_ZLIB
|
|
|
|
if (strcmp(name, "unused_data") == 0) {
|
|
Py_INCREF(self->unused_data);
|
|
retval = self->unused_data;
|
|
} else if (strcmp(name, "unconsumed_tail") == 0) {
|
|
Py_INCREF(self->unconsumed_tail);
|
|
retval = self->unconsumed_tail;
|
|
} else
|
|
retval = Py_FindMethod(Decomp_methods, (PyObject *)self, name);
|
|
|
|
LEAVE_ZLIB
|
|
|
|
return retval;
|
|
}
|
|
|
|
PyDoc_STRVAR(adler32__doc__,
|
|
"adler32(string[, start]) -- Compute an Adler-32 checksum of string.\n"
|
|
"\n"
|
|
"An optional starting value can be specified. The returned checksum is\n"
|
|
"a signed integer.");
|
|
|
|
static PyObject *
|
|
PyZlib_adler32(PyObject *self, PyObject *args)
|
|
{
|
|
unsigned int adler32val = 1; /* adler32(0L, Z_NULL, 0) */
|
|
Byte *buf;
|
|
int len, signed_val;
|
|
|
|
if (!PyArg_ParseTuple(args, "s#|I:adler32", &buf, &len, &adler32val))
|
|
return NULL;
|
|
/* In Python 2.x we return a signed integer regardless of native platform
|
|
* long size (the 32bit unsigned long is treated as 32-bit signed and sign
|
|
* extended into a 64-bit long inside the integer object). 3.0 does the
|
|
* right thing and returns unsigned. http://bugs.python.org/issue1202 */
|
|
signed_val = adler32(adler32val, buf, len);
|
|
return PyInt_FromLong(signed_val);
|
|
}
|
|
|
|
PyDoc_STRVAR(crc32__doc__,
|
|
"crc32(string[, start]) -- Compute a CRC-32 checksum of string.\n"
|
|
"\n"
|
|
"An optional starting value can be specified. The returned checksum is\n"
|
|
"a signed integer.");
|
|
|
|
static PyObject *
|
|
PyZlib_crc32(PyObject *self, PyObject *args)
|
|
{
|
|
unsigned int crc32val = 0; /* crc32(0L, Z_NULL, 0) */
|
|
Byte *buf;
|
|
int len, signed_val;
|
|
|
|
if (!PyArg_ParseTuple(args, "s#|I:crc32", &buf, &len, &crc32val))
|
|
return NULL;
|
|
/* In Python 2.x we return a signed integer regardless of native platform
|
|
* long size (the 32bit unsigned long is treated as 32-bit signed and sign
|
|
* extended into a 64-bit long inside the integer object). 3.0 does the
|
|
* right thing and returns unsigned. http://bugs.python.org/issue1202 */
|
|
signed_val = crc32(crc32val, buf, len);
|
|
return PyInt_FromLong(signed_val);
|
|
}
|
|
|
|
|
|
static PyMethodDef zlib_methods[] =
|
|
{
|
|
{"adler32", (PyCFunction)PyZlib_adler32, METH_VARARGS,
|
|
adler32__doc__},
|
|
{"compress", (PyCFunction)PyZlib_compress, METH_VARARGS,
|
|
compress__doc__},
|
|
{"compressobj", (PyCFunction)PyZlib_compressobj, METH_VARARGS,
|
|
compressobj__doc__},
|
|
{"crc32", (PyCFunction)PyZlib_crc32, METH_VARARGS,
|
|
crc32__doc__},
|
|
{"decompress", (PyCFunction)PyZlib_decompress, METH_VARARGS,
|
|
decompress__doc__},
|
|
{"decompressobj", (PyCFunction)PyZlib_decompressobj, METH_VARARGS,
|
|
decompressobj__doc__},
|
|
{NULL, NULL}
|
|
};
|
|
|
|
static PyTypeObject Comptype = {
|
|
PyVarObject_HEAD_INIT(0, 0)
|
|
"zlib.Compress",
|
|
sizeof(compobject),
|
|
0,
|
|
(destructor)Comp_dealloc, /*tp_dealloc*/
|
|
0, /*tp_print*/
|
|
(getattrfunc)Comp_getattr, /*tp_getattr*/
|
|
0, /*tp_setattr*/
|
|
0, /*tp_compare*/
|
|
0, /*tp_repr*/
|
|
0, /*tp_as_number*/
|
|
0, /*tp_as_sequence*/
|
|
0, /*tp_as_mapping*/
|
|
};
|
|
|
|
static PyTypeObject Decomptype = {
|
|
PyVarObject_HEAD_INIT(0, 0)
|
|
"zlib.Decompress",
|
|
sizeof(compobject),
|
|
0,
|
|
(destructor)Decomp_dealloc, /*tp_dealloc*/
|
|
0, /*tp_print*/
|
|
(getattrfunc)Decomp_getattr, /*tp_getattr*/
|
|
0, /*tp_setattr*/
|
|
0, /*tp_compare*/
|
|
0, /*tp_repr*/
|
|
0, /*tp_as_number*/
|
|
0, /*tp_as_sequence*/
|
|
0, /*tp_as_mapping*/
|
|
};
|
|
|
|
PyDoc_STRVAR(zlib_module_documentation,
|
|
"The functions in this module allow compression and decompression using the\n"
|
|
"zlib library, which is based on GNU zip.\n"
|
|
"\n"
|
|
"adler32(string[, start]) -- Compute an Adler-32 checksum.\n"
|
|
"compress(string[, level]) -- Compress string, with compression level in 0-9.\n"
|
|
"compressobj([level]) -- Return a compressor object.\n"
|
|
"crc32(string[, start]) -- Compute a CRC-32 checksum.\n"
|
|
"decompress(string,[wbits],[bufsize]) -- Decompresses a compressed string.\n"
|
|
"decompressobj([wbits]) -- Return a decompressor object.\n"
|
|
"\n"
|
|
"'wbits' is window buffer size.\n"
|
|
"Compressor objects support compress() and flush() methods; decompressor\n"
|
|
"objects support decompress() and flush().");
|
|
|
|
PyMODINIT_FUNC
|
|
PyInit_zlib(void)
|
|
{
|
|
PyObject *m, *ver;
|
|
Py_TYPE(&Comptype) = &PyType_Type;
|
|
Py_TYPE(&Decomptype) = &PyType_Type;
|
|
m = Py_InitModule4("zlib", zlib_methods,
|
|
zlib_module_documentation,
|
|
(PyObject*)NULL,PYTHON_API_VERSION);
|
|
if (m == NULL)
|
|
return;
|
|
|
|
ZlibError = PyErr_NewException("zlib.error", NULL, NULL);
|
|
if (ZlibError != NULL) {
|
|
Py_INCREF(ZlibError);
|
|
PyModule_AddObject(m, "error", ZlibError);
|
|
}
|
|
PyModule_AddIntConstant(m, "MAX_WBITS", MAX_WBITS);
|
|
PyModule_AddIntConstant(m, "DEFLATED", DEFLATED);
|
|
PyModule_AddIntConstant(m, "DEF_MEM_LEVEL", DEF_MEM_LEVEL);
|
|
PyModule_AddIntConstant(m, "Z_BEST_SPEED", Z_BEST_SPEED);
|
|
PyModule_AddIntConstant(m, "Z_BEST_COMPRESSION", Z_BEST_COMPRESSION);
|
|
PyModule_AddIntConstant(m, "Z_DEFAULT_COMPRESSION", Z_DEFAULT_COMPRESSION);
|
|
PyModule_AddIntConstant(m, "Z_FILTERED", Z_FILTERED);
|
|
PyModule_AddIntConstant(m, "Z_HUFFMAN_ONLY", Z_HUFFMAN_ONLY);
|
|
PyModule_AddIntConstant(m, "Z_DEFAULT_STRATEGY", Z_DEFAULT_STRATEGY);
|
|
|
|
PyModule_AddIntConstant(m, "Z_FINISH", Z_FINISH);
|
|
PyModule_AddIntConstant(m, "Z_NO_FLUSH", Z_NO_FLUSH);
|
|
PyModule_AddIntConstant(m, "Z_SYNC_FLUSH", Z_SYNC_FLUSH);
|
|
PyModule_AddIntConstant(m, "Z_FULL_FLUSH", Z_FULL_FLUSH);
|
|
|
|
ver = PyString_FromString(ZLIB_VERSION);
|
|
if (ver != NULL)
|
|
PyModule_AddObject(m, "ZLIB_VERSION", ver);
|
|
|
|
PyModule_AddStringConstant(m, "__version__", "1.0");
|
|
|
|
#ifdef WITH_THREAD
|
|
zlib_lock = PyThread_allocate_lock();
|
|
#endif /* WITH_THREAD */
|
|
}
|