Windows: Fixes for corner case leaks when reusing device references #64
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If windows_get_device_list() found a device that already existed, it would erronenously increment the parent_dev refcount and cause a reference leak - the parent device would never be released.
windows_get_device_list was leaking dev_interface_path (in either of two possible places) when a pre-existing device reference was reused.
As per comment in existing code, get_devinfo_data() should be called repeatedly until it returns false indicating the handle has been released. When testing I could see cases where this didn't happen. However it didn't seem like my program actually leaked any handles. This commit errs on the safe side anyhow.
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Applied the first two commits. The third is not needed, so it was omitted. Thanks for submitting this! |
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Where is this pull request merged? I still have this issue with version 1.0.23 |
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@rezahousseini Please create a new issue if you still see the issue in 1.0.24 or latest git. Thanks. |
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I noticed my libusb-based program was leaking memory under Windows and tracked it down to leaks that occur when libusb_get_device_list() reuses existing device references.
A test program that demonstrates the problem is here:
https://gist.github.com/projectgus/c9e29f90397202dbba38
The three commits in this PR fix these problems for me.
I've been cross-compiling with mingw and testing on Windows 7 and XP 32-bit. But I don't think those details are relevant.
BTW, thanks very much to everyone who works on libusb. It's marvellous being able to write cross-platform code for something as complex as USB, and have it run everywhere. I am even more admiring of libusb after today, having now become more familiar with the actual Windows USB stack. ;)