symbian-qemu-0.9.1-12/python-2.6.1/Modules/zlibmodule.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Modules/zlibmodule.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,1039 @@
+/* zlibmodule.c -- gzip-compatible data compression */
+/* See http://www.gzip.org/zlib/ */
+
+/* Windows users:  read Python's PCbuild\readme.txt */
+
+
+#include "Python.h"
+#include "zlib.h"
+
+#ifdef WITH_THREAD
+#include "pythread.h"
+
+/* #defs ripped off from _tkinter.c, even though the situation here is much
+   simpler, because we don't have to worry about waiting for Tcl
+   events!  And, since zlib itself is threadsafe, we don't need to worry
+   about re-entering zlib functions.
+
+   N.B.
+
+   Since ENTER_ZLIB and LEAVE_ZLIB only need to be called on functions
+   that modify the components of preexisting de/compress objects, it
+   could prove to be a performance gain on multiprocessor machines if
+   there was an de/compress object-specific lock.  However, for the
+   moment the ENTER_ZLIB and LEAVE_ZLIB calls are global for ALL
+   de/compress objects.
+ */
+
+static PyThread_type_lock zlib_lock = NULL; /* initialized on module load */
+
+#define ENTER_ZLIB \
+	Py_BEGIN_ALLOW_THREADS \
+	PyThread_acquire_lock(zlib_lock, 1); \
+	Py_END_ALLOW_THREADS
+
+#define LEAVE_ZLIB \
+	PyThread_release_lock(zlib_lock);
+
+#else
+
+#define ENTER_ZLIB
+#define LEAVE_ZLIB
+
+#endif
+
+/* The following parameters are copied from zutil.h, version 0.95 */
+#define DEFLATED   8
+#if MAX_MEM_LEVEL >= 8
+#  define DEF_MEM_LEVEL 8
+#else
+#  define DEF_MEM_LEVEL  MAX_MEM_LEVEL
+#endif
+#define DEF_WBITS MAX_WBITS
+
+/* The output buffer will be increased in chunks of DEFAULTALLOC bytes. */
+#define DEFAULTALLOC (16*1024)
+#define PyInit_zlib initzlib
+
+static PyTypeObject Comptype;
+static PyTypeObject Decomptype;
+
+static PyObject *ZlibError;
+
+typedef struct
+{
+    PyObject_HEAD
+    z_stream zst;
+    PyObject *unused_data;
+    PyObject *unconsumed_tail;
+    int is_initialised;
+} compobject;
+
+static void
+zlib_error(z_stream zst, int err, char *msg)
+{
+    if (zst.msg == Z_NULL)
+	PyErr_Format(ZlibError, "Error %d %s", err, msg);
+    else
+	PyErr_Format(ZlibError, "Error %d %s: %.200s", err, msg, zst.msg);
+}
+
+PyDoc_STRVAR(compressobj__doc__,
+"compressobj([level]) -- Return a compressor object.\n"
+"\n"
+"Optional arg level is the compression level, in 1-9.");
+
+PyDoc_STRVAR(decompressobj__doc__,
+"decompressobj([wbits]) -- Return a decompressor object.\n"
+"\n"
+"Optional arg wbits is the window buffer size.");
+
+static compobject *
+newcompobject(PyTypeObject *type)
+{
+    compobject *self;
+    self = PyObject_New(compobject, type);
+    if (self == NULL)
+	return NULL;
+    self->is_initialised = 0;
+    self->unused_data = PyString_FromString("");
+    if (self->unused_data == NULL) {
+	Py_DECREF(self);
+	return NULL;
+    }
+    self->unconsumed_tail = PyString_FromString("");
+    if (self->unconsumed_tail == NULL) {
+	Py_DECREF(self);
+	return NULL;
+    }
+    return self;
+}
+
+PyDoc_STRVAR(compress__doc__,
+"compress(string[, level]) -- Returned compressed string.\n"
+"\n"
+"Optional arg level is the compression level, in 1-9.");
+
+static PyObject *
+PyZlib_compress(PyObject *self, PyObject *args)
+{
+    PyObject *ReturnVal = NULL;
+    Byte *input, *output;
+    int length, level=Z_DEFAULT_COMPRESSION, err;
+    z_stream zst;
+
+    /* require Python string object, optional 'level' arg */
+    if (!PyArg_ParseTuple(args, "s#|i:compress", &input, &length, &level))
+	return NULL;
+
+    zst.avail_out = length + length/1000 + 12 + 1;
+
+    output = (Byte*)malloc(zst.avail_out);
+    if (output == NULL) {
+	PyErr_SetString(PyExc_MemoryError,
+			"Can't allocate memory to compress data");
+	return NULL;
+    }
+
+    /* Past the point of no return.  From here on out, we need to make sure
+       we clean up mallocs & INCREFs. */
+
+    zst.zalloc = (alloc_func)NULL;
+    zst.zfree = (free_func)Z_NULL;
+    zst.next_out = (Byte *)output;
+    zst.next_in = (Byte *)input;
+    zst.avail_in = length;
+    err = deflateInit(&zst, level);
+
+    switch(err) {
+    case(Z_OK):
+	break;
+    case(Z_MEM_ERROR):
+	PyErr_SetString(PyExc_MemoryError,
+			"Out of memory while compressing data");
+	goto error;
+    case(Z_STREAM_ERROR):
+	PyErr_SetString(ZlibError,
+			"Bad compression level");
+	goto error;
+    default:
+        deflateEnd(&zst);
+	zlib_error(zst, err, "while compressing data");
+	goto error;
+    }
+
+    Py_BEGIN_ALLOW_THREADS;
+    err = deflate(&zst, Z_FINISH);
+    Py_END_ALLOW_THREADS;
+
+    if (err != Z_STREAM_END) {
+	zlib_error(zst, err, "while compressing data");
+	deflateEnd(&zst);
+	goto error;
+    }
+
+    err=deflateEnd(&zst);
+    if (err == Z_OK)
+	ReturnVal = PyString_FromStringAndSize((char *)output,
+					       zst.total_out);
+    else
+	zlib_error(zst, err, "while finishing compression");
+
+ error:
+    free(output);
+
+    return ReturnVal;
+}
+
+PyDoc_STRVAR(decompress__doc__,
+"decompress(string[, wbits[, bufsize]]) -- Return decompressed string.\n"
+"\n"
+"Optional arg wbits is the window buffer size.  Optional arg bufsize is\n"
+"the initial output buffer size.");
+
+static PyObject *
+PyZlib_decompress(PyObject *self, PyObject *args)
+{
+    PyObject *result_str;
+    Byte *input;
+    int length, err;
+    int wsize=DEF_WBITS;
+    Py_ssize_t r_strlen=DEFAULTALLOC;
+    z_stream zst;
+
+    if (!PyArg_ParseTuple(args, "s#|in:decompress",
+			  &input, &length, &wsize, &r_strlen))
+	return NULL;
+
+    if (r_strlen <= 0)
+	r_strlen = 1;
+
+    zst.avail_in = length;
+    zst.avail_out = r_strlen;
+
+    if (!(result_str = PyString_FromStringAndSize(NULL, r_strlen)))
+	return NULL;
+
+    zst.zalloc = (alloc_func)NULL;
+    zst.zfree = (free_func)Z_NULL;
+    zst.next_out = (Byte *)PyString_AS_STRING(result_str);
+    zst.next_in = (Byte *)input;
+    err = inflateInit2(&zst, wsize);
+
+    switch(err) {
+    case(Z_OK):
+	break;
+    case(Z_MEM_ERROR):
+	PyErr_SetString(PyExc_MemoryError,
+			"Out of memory while decompressing data");
+	goto error;
+    default:
+        inflateEnd(&zst);
+	zlib_error(zst, err, "while preparing to decompress data");
+	goto error;
+    }
+
+    do {
+	Py_BEGIN_ALLOW_THREADS
+	err=inflate(&zst, Z_FINISH);
+	Py_END_ALLOW_THREADS
+
+	switch(err) {
+	case(Z_STREAM_END):
+	    break;
+	case(Z_BUF_ERROR):
+	    /*
+	     * If there is at least 1 byte of room according to zst.avail_out
+	     * and we get this error, assume that it means zlib cannot
+	     * process the inflate call() due to an error in the data.
+	     */
+	    if (zst.avail_out > 0) {
+		PyErr_Format(ZlibError, "Error %i while decompressing data",
+			     err);
+		inflateEnd(&zst);
+		goto error;
+	    }
+	    /* fall through */
+	case(Z_OK):
+	    /* need more memory */
+	    if (_PyString_Resize(&result_str, r_strlen << 1) < 0) {
+		inflateEnd(&zst);
+		goto error;
+	    }
+	    zst.next_out = (unsigned char *)PyString_AS_STRING(result_str) \
+		+ r_strlen;
+	    zst.avail_out = r_strlen;
+	    r_strlen = r_strlen << 1;
+	    break;
+	default:
+	    inflateEnd(&zst);
+	    zlib_error(zst, err, "while decompressing data");
+	    goto error;
+	}
+    } while (err != Z_STREAM_END);
+
+    err = inflateEnd(&zst);
+    if (err != Z_OK) {
+	zlib_error(zst, err, "while finishing data decompression");
+	goto error;
+    }
+
+    _PyString_Resize(&result_str, zst.total_out);
+    return result_str;
+
+ error:
+    Py_XDECREF(result_str);
+    return NULL;
+}
+
+static PyObject *
+PyZlib_compressobj(PyObject *selfptr, PyObject *args)
+{
+    compobject *self;
+    int level=Z_DEFAULT_COMPRESSION, method=DEFLATED;
+    int wbits=MAX_WBITS, memLevel=DEF_MEM_LEVEL, strategy=0, err;
+
+    if (!PyArg_ParseTuple(args, "|iiiii:compressobj", &level, &method, &wbits,
+			  &memLevel, &strategy))
+	return NULL;
+
+    self = newcompobject(&Comptype);
+    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 = deflateInit2(&self->zst, level, method, wbits, memLevel, strategy);
+    switch(err) {
+    case (Z_OK):
+	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, 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;
+}
+
+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, old_length, length = DEFAULTALLOC;
+    int max_length = 0;
+    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
+    }
+
+    /* Not all of the compressed data could be accommodated in the output buffer
+       of specified size. Return the unconsumed tail in an attribute.*/
+    if(max_length) {
+	Py_DECREF(self->unconsumed_tail);
+	self->unconsumed_tail = PyString_FromStringAndSize((char *)self->zst.next_in,
+							   self->zst.avail_in);
+	if(!self->unconsumed_tail) {
+	    Py_DECREF(RetVal);
+	    RetVal = NULL;
+	    goto error;
+	}
+    }
+
+    /* The end of the compressed data has been reached, so set the
+       unused_data attribute to a string containing the remainder of the
+       data in the string.  Note that this is also a logical place to call
+       inflateEnd, but the old behaviour of only calling it on flush() is
+       preserved.
+    */
+    if (err == Z_STREAM_END) {
+	Py_XDECREF(self->unused_data);  /* Free original empty string */
+	self->unused_data = PyString_FromStringAndSize(
+	    (char *)self->zst.next_in, self->zst.avail_in);
+	if (self->unused_data == NULL) {
+	    Py_DECREF(RetVal);
+	    goto 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.
+	*/
+    } else if (err != Z_OK && err != Z_BUF_ERROR) {
+	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_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 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 1-9.\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 */
+}