Bug 952 – segfault with QBuffer.open()

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Bug 952 - segfault with QBuffer.open()

Summary:

segfault with QBuffer.open()

Status:	CLOSED INVALID

Product:	PySide
Classification:	Unclassified
Component:	QtCore
Version:	1.0.4
Platform:	Macintosh Mac OS

Importance:	P5 major
Assigned To:	renato filho

URL:

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2011-08-02 04:17 EEST by Daniel Ashbrook
Modified:	2011-08-23 00:37 EEST (History)
CC List:	8 users (show)

See Also:

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Description Daniel Ashbrook 2011-08-02 04:17:50 EEST

The following code segfaults every few times it is run:

from PySide.QtCore import *
from random import random
A = ''.join(str(int(10000*random())) for i in xrange(10000))
buf = QBuffer(QByteArray(A))
buf.open(QIODevice.ReadOnly)

Also on occasion it gives the error "QBuffer::seek: Invalid pos: 0".


I'm on OSX 10.6.8 with Qt 4.7.3 and PySide from
pyside-1.0.4-r1-qt47-py26apple.pkg.

Comment 1 Hugo Parente Lima 2011-08-02 19:53:07 EEST

You need to keep the buffer you are point to valid, i.e. not delete the
QByteArray while reading the buffer, try it:

from PySide.QtCore import *
from random import random
A = QByteArray(''.join(str(int(10000*random())) for i in xrange(10000)))
buf = QBuffer(A)
buf.open(QIODevice.ReadOnly)

Comment 2 Daniel Ashbrook 2011-08-02 20:07:53 EEST

Ah, I see. In that case, shouldn't the QBuffer increase the reference count on
the QByteArray?

Comment 3 Daniel Ashbrook 2011-08-02 20:20:17 EEST

Oops, I see that's Qt behavior and is documented:

"The caller is responsible for ensuring that byteArray remains valid until the
QBuffer is destroyed, or until setBuffer() is called to change the buffer.
QBuffer doesn't take ownership of the QByteArray."

Comment 4 renato filho 2011-08-23 00:37:19 EEST

Release PySide 1.0.6