On Fri, Feb 28, 2025 at 04:29:12PM +0000, Aditya Garg wrote: > From: Hector Martin <marcan@xxxxxxxxx> > > %p4cc is designed for DRM/V4L2 FourCCs with their specific quirks, but > it's useful to be able to print generic 4-character codes formatted as > an integer. Extend it to add format specifiers for printing generic > 32-bit FourCCs with various endian semantics: > %p4ch Host-endian > %p4cn Reverse-endian Call them Host order, Network order as they are very established endianesses. > %p4cl Little-endian You have extra spaces here > %p4cb Big-endian > > The endianness determines how bytes are interpreted as a u32, and the > FourCC is then always printed MSByte-first (this is the opposite of > V4L/DRM FourCCs). This covers most practical cases, e.g. %p4cn would > allow printing LSByte-first FourCCs stored in host endian order > (other than the hex form being in character order, not the integer > value). ... > +Generic FourCC code > +------------------- > + > +:: > + %p4c[hnlb] gP00 (0x67503030) > + > +Print a generic FourCC code, as both ASCII characters and its numerical > +value as hexadecimal. > + > +The generic FourCC code is always printed in the big-endian format, > +the most significant byte first. This is the opposite of V4L/DRM FourCCs. > + > +The additional ``h``, ``n``, ``l``, and ``b`` specifiers define what > +endianness is used to load the stored bytes. The data might be interpreted > +using the host-endian, reverse-host-endian, little-endian, or big-endian. host order, network order > +Passed by reference. > + > +Examples for a little-endian machine, given &(u32)0x67503030:: > + > + %p4ch gP00 (0x67503030) > + %p4cn 00Pg (0x30305067) > + %p4cl gP00 (0x67503030) > + %p4cb 00Pg (0x30305067) > + > +Examples for a big-endian machine, given &(u32)0x67503030:: > + > + %p4ch gP00 (0x67503030) > + %p4cn 00Pg (0x30305067) > + %p4cl 00Pg (0x30305067) > + %p4cb gP00 (0x67503030) For the reference on the terms: https://www.ibm.com/docs/ja/zvm/7.2?topic=domains-network-byte-order-host-byte-order Otherwise LGTM. With the above addressed, FWIW, Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> -- With Best Regards, Andy Shevchenko
