Messages in this thread | | | Date | Wed, 27 Sep 2023 15:27:52 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v4 1/5] tools: iio: iio_generic_buffer ensure alignment |
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On Wed, Sep 27, 2023 at 11:26:07AM +0300, Matti Vaittinen wrote: > The iio_generic_buffer can return garbage values when the total size of > scan data is not a multiple of the largest element in the scan. This can be > demonstrated by reading a scan, consisting, for example of one 4-byte and > one 2-byte element, where the 4-byte element is first in the buffer. > > The IIO generic buffer code does not take into account the last two > padding bytes that are needed to ensure that the 4-byte data for next > scan is correctly aligned. > > Add the padding bytes required to align the next sample with the scan size.
...
> + /* > + * We wan't the data in next sample to also be properly aligned so
Pardon me, won't or want, I didn't get?..
> + * we'll add padding at the end if needed. > + * > + * Please note, this code does ensure alignment to maximum channel > + * size. It works only as long as the channel sizes are 1, 2, 4 or 8 > + * bytes. Also, on 32 bit platforms it might be enough to align also
32-bit
> + * the 8 byte elements to 4 byte boundary - which this code is not
8-byte 4-byte
> + * doing. > + */
-- With Best Regards, Andy Shevchenko
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