source: vbox/trunk/src/libs/xpcom18a4/python/src/PyGInputStream.cpp

/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Python XPCOM language bindings.
 *
 * The Initial Developer of the Original Code is
 * ActiveState Tool Corp.
 * Portions created by the Initial Developer are Copyright (C) 2000
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Mark Hammond <MarkH@ActiveState.com> (original author)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

// PyGInputStream.cpp
//
// This code is part of the XPCOM extensions for Python.
//
// Written October 2000 by Mark Hammond.
//
// Based heavily on the Python COM support, which is
// (c) Mark Hammond and Greg Stein.
//
// (c) 2000, ActiveState corp.

#include "PyXPCOM_std.h"
#include <nsIInputStream.h>

class PyG_nsIInputStream : public PyG_Base, public nsIInputStream
{
public:
        PyG_nsIInputStream(PyObject *instance) : PyG_Base(instance, NS_GET_IID(nsIInputStream)) {;}
        PYGATEWAY_BASE_SUPPORT(nsIInputStream, PyG_Base);

        NS_IMETHOD Close(void);
        NS_IMETHOD Available(PRUint32 *_retval);
        NS_IMETHOD Read(char * buf, PRUint32 count, PRUint32 *_retval);
        NS_IMETHOD ReadSegments(nsWriteSegmentFun writer, void * closure, PRUint32 count, PRUint32 *_retval);
        NS_IMETHOD IsNonBlocking(PRBool *aNonBlocking);
};


DECLHIDDEN (PyG_Base *) MakePyG_nsIInputStream(PyObject *instance)
{
        return new PyG_nsIInputStream(instance);
}

NS_IMETHODIMP
PyG_nsIInputStream::Close()
{
        CEnterLeavePython _celp;
        const char *methodName = "close";
        return InvokeNativeViaPolicy(methodName, NULL);
}

NS_IMETHODIMP
PyG_nsIInputStream::Available(PRUint32 *_retval)
{
        NS_PRECONDITION(_retval, "null pointer");
        CEnterLeavePython _celp;
        PyObject *ret;
        const char *methodName = "available";
        nsresult nr = InvokeNativeViaPolicy(methodName, &ret);
        if (NS_SUCCEEDED(nr)) {
                *_retval = PyInt_AsLong(ret);
                if (PyErr_Occurred())
                        nr = HandleNativeGatewayError(methodName);
                Py_XDECREF(ret);
        }
        return nr;
}

NS_IMETHODIMP
PyG_nsIInputStream::Read(char * buf, PRUint32 count, PRUint32 *_retval)
{
        NS_PRECONDITION(_retval, "null pointer");
        NS_PRECONDITION(buf, "null pointer");
        CEnterLeavePython _celp;
        PyObject *ret;
        const char *methodName = "read";
        nsresult nr = InvokeNativeViaPolicy(methodName, &ret, "i", count);
        if (NS_SUCCEEDED(nr)) {
#if 0 /* VBox: new buffer protocol (though I could use it for Py_LIMITED_API and ditch the warning, but cpython specific) */
                Py_buffer py_view;
                if (PyObject_GetBuffer(ret, &py_view, PyBUF_SIMPLE) == 0) {
                        if (py_view.len <= count) {
                                count = py_view.len;
                        } else {
                                PyXPCOM_LogWarning("nsIInputStream::read() was asked for %d bytes, but the string returned is %d bytes - truncating!\n", count, py_size);
                        }
                        memcpy(buf, py_view.py_buf, count);
                        PyBuffer_Release(&py_view);
                        *_retval = count;
                } else {
                        PyErr_Format(PyExc_TypeError, "nsIInputStream::read() method must return a buffer object - not a '%s' object", PyXPCOM_ObTypeName(ret));
                        nr = HandleNativeGatewayError(methodName);
                }
#else  /* Old protocol: */
# ifndef VBOX /* unsafe cast on 64-bit hosts. */
                PRUint32 py_size;
                const void *py_buf;
                if (PyObject_AsReadBuffer(ret, &py_buf, (Py_ssize_t*)&py_size)!=0) {
# else  /* VBOX */
                const void *py_buf;
#  if PY_VERSION_HEX >= 0x02050000 || defined(PY_SSIZE_T_MIN)
                Py_ssize_t py_size;
#  else
                int py_size;
#  endif
                if (PyObject_AsReadBuffer(ret, &py_buf, &py_size)!=0) {
# endif /* VBOX */
                        PyErr_Format(PyExc_TypeError, "nsIInputStream::read() method must return a buffer object - not a '%s' object", PyXPCOM_ObTypeName(ret));
                        nr = HandleNativeGatewayError(methodName);
                } else {
                        if (py_size > count) {
                                PyXPCOM_LogWarning("nsIInputStream::read() was asked for %d bytes, but the string returned is %d bytes - truncating!\n", count, py_size);
                                py_size = count;
                        }
                        memcpy(buf, py_buf, py_size);
                        *_retval = py_size;
                }
#endif
        }
        return nr;
}


NS_IMETHODIMP
PyG_nsIInputStream::ReadSegments(nsWriteSegmentFun writer, void * closure, PRUint32 count, PRUint32 *_retval)
{
        NS_WARNING("ReadSegments() not implemented!!!");
        return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
PyG_nsIInputStream::IsNonBlocking(PRBool *aNonBlocking)
{
        NS_PRECONDITION(aNonBlocking, "null pointer");
        CEnterLeavePython _celp;
        PyObject *ret;
        const char *methodName = "isNonBlocking";
        nsresult nr = InvokeNativeViaPolicy(methodName, &ret);
        if (NS_SUCCEEDED(nr)) {
                *aNonBlocking = PyInt_AsLong(ret);
                if (PyErr_Occurred())
                        nr = HandleNativeGatewayError(methodName);
                Py_XDECREF(ret);
        }
        return nr;
}