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Date:   Sat, 14 Aug 2021 09:38:34 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Uwe Kleine-K??nig <u.kleine-koenig@pengutronix.de>
Cc:     Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCH v3 4/8] PCI: replace pci_dev::driver usage that gets the
 driver name
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References: <20210811080637.2596434-1-u.kleine-koenig@pengutronix.de>
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On Thu, Aug 12, 2021 at 10:14:25AM +0200, Uwe Kleine-K??nig wrote:
> dev_driver_string() might return "" (via dev_bus_name()). If that happens
> *drvstr == '\0' becomes true.
> 
> Would the following be better?:
> 
> 	const char *drvstr;
> 
> 	if (pdev)
> 		return "<null>";
> 
> 	drvstr = dev_driver_string(&pdev->dev);
> 
> 	if (!strcmp(drvstr, ""))
> 		return "<null>";
> 
> 	return drvstr;
> 
> When I thought about this hunk I considered it ugly to have "<null>" in
> it twice.

Well, if you want to avoid that you can do:

	if (pdev) {
		const char *name = dev_driver_string(&pdev->dev);

		if (strcmp(drvstr, ""))
			return name;
	}
	return "<null>";

Which would be a lot more readable.