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Comparing libecb/ecb.pod (file contents):
Revision 1.74 by root, Mon Nov 19 00:27:38 2018 UTC vs.
Revision 1.76 by root, Mon Jan 20 13:13:56 2020 UTC

58 58
59=head2 TYPES / TYPE SUPPORT 59=head2 TYPES / TYPE SUPPORT
60 60
61ecb.h makes sure that the following types are defined (in the expected way): 61ecb.h makes sure that the following types are defined (in the expected way):
62 62
63 int8_t uint8_t int16_t uint16_t 63 int8_t uint8_
64 int32_t uint32_t int64_t uint64_t 64 int16_t uint16_t
65 int32_t uint32_
66 int64_t uint64_t
67 int_fast8_t uint_fast8_t
68 int_fast16_t uint_fast16_t
69 int_fast32_t uint_fast32_t
70 int_fast64_t uint_fast64_t
65 intptr_t uintptr_t 71 intptr_t uintptr_t
66 72
67The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this 73The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this
68platform (currently C<4> or C<8>) and can be used in preprocessor 74platform (currently C<4> or C<8>) and can be used in preprocessor
69expressions. 75expressions.
70 76
402 408
403=head2 OPTIMISATION HINTS 409=head2 OPTIMISATION HINTS
404 410
405=over 4 411=over 4
406 412
413=item ECB_OPTIMIZE_SIZE
414
415Is C<1> when the compiler optimizes for size, C<0> otherwise. This symbol
416can also be defined before including F<ecb.h>, in which case it will be
417unchanged.
418
407=item bool ecb_is_constant (expr) 419=item bool ecb_is_constant (expr)
408 420
409Returns true iff the expression can be deduced to be a compile-time 421Returns true iff the expression can be deduced to be a compile-time
410constant, and false otherwise. 422constant, and false otherwise.
411 423
656 668
657These functions return the value of the 16-bit (32-bit, 64-bit) value 669These functions return the value of the 16-bit (32-bit, 64-bit) value
658C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in 670C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in
659C<ecb_bswap32>). 671C<ecb_bswap32>).
660 672
673=item T ecb_bswap (T x) [C++]
674
675For C++, an additional generic bswap function is provided. It supports
676C<uint8_t>, C<uint16_t>, C<uint32_t> and C<uint64_t>.
677
661=item uint8_t ecb_rotl8 (uint8_t x, unsigned int count) 678=item uint8_t ecb_rotl8 (uint8_t x, unsigned int count)
662 679
663=item uint16_t ecb_rotl16 (uint16_t x, unsigned int count) 680=item uint16_t ecb_rotl16 (uint16_t x, unsigned int count)
664 681
665=item uint32_t ecb_rotl32 (uint32_t x, unsigned int count) 682=item uint32_t ecb_rotl32 (uint32_t x, unsigned int count)
679(C<ecb_rotl>). 696(C<ecb_rotl>).
680 697
681Current GCC versions understand these functions and usually compile them 698Current GCC versions understand these functions and usually compile them
682to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on 699to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on
683x86). 700x86).
701
702=back
703
704=head2 HOST ENDIANNESS CONVERSION
705
706=over 4
707
708=item uint_fast16_t ecb_be_u16_to_host (uint_fast16_t v)
709
710=item uint_fast32_t ecb_be_u32_to_host (uint_fast32_t v)
711
712=item uint_fast64_t ecb_be_u64_to_host (uint_fast64_t v)
713
714=item uint_fast16_t ecb_le_u16_to_host (uint_fast16_t v)
715
716=item uint_fast32_t ecb_le_u32_to_host (uint_fast32_t v)
717
718=item uint_fast64_t ecb_le_u64_to_host (uint_fast64_t v)
719
720Convert an unsigned 16, 32 or 64 bit value from big or little endian to host byte order.
721
722The naming convention is C<ecb_>(C<be>|C<le>)C<_u>C<16|32|64>C<_to_host>,
723where be and le stand for big endian and little endian, respectively.
724
725=item uint_fast16_t ecb_host_to_be_u16 (uint_fast16_t v)
726
727=item uint_fast32_t ecb_host_to_be_u32 (uint_fast32_t v)
728
729=item uint_fast64_t ecb_host_to_be_u64 (uint_fast64_t v)
730
731=item uint_fast16_t ecb_host_to_le_u16 (uint_fast16_t v)
732
733=item uint_fast32_t ecb_host_to_le_u32 (uint_fast32_t v)
734
735=item uint_fast64_t ecb_host_to_le_u64 (uint_fast64_t v)
736
737Like above, but converts I<from> host byte order to the specified
738endianness.
739
740=back
741
742In C++ the following additional functions are supported:
743
744=over 4
745
746=item T ecb_be_to_host (T v)
747
748=item T ecb_le_to_host (T v)
749
750=item T ecb_host_to_be (T v)
751
752=item T ecb_host_to_le (T v)
753
754These work like their C counterparts, above, but use templates for the
755type, which make them useful in generic code.
756
757C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>
758(so unlike their C counterparts, there is a version for C<uint8_t>, which
759again can be useful in generic code).
760
761=head2 UNALIGNED LOAD/STORE
762
763These function load or store unaligned multi-byte values.
764
765=over 4
766
767=item uint_fast16_t ecb_peek_u16_u (const void *ptr)
768
769=item uint_fast32_t ecb_peek_u32_u (const void *ptr)
770
771=item uint_fast64_t ecb_peek_u64_u (const void *ptr)
772
773These functions load an unaligned, unsigned 16, 32 or 64 bit value from
774memory.
775
776=item uint_fast16_t ecb_peek_be_u16_u (const void *ptr)
777
778=item uint_fast32_t ecb_peek_be_u32_u (const void *ptr)
779
780=item uint_fast64_t ecb_peek_be_u64_u (const void *ptr)
781
782=item uint_fast16_t ecb_peek_le_u16_u (const void *ptr)
783
784=item uint_fast32_t ecb_peek_le_u32_u (const void *ptr)
785
786=item uint_fast64_t ecb_peek_le_u64_u (const void *ptr)
787
788Like above, but additionally convert from big endian (C<be>) or little
789endian (C<le>) byte order to host byte order while doing so.
790
791=item ecb_poke_u16_u (void *ptr, uint16_t v)
792
793=item ecb_poke_u32_u (void *ptr, uint32_t v)
794
795=item ecb_poke_u64_u (void *ptr, uint64_t v)
796
797These functions store an unaligned, unsigned 16, 32 or 64 bit value to
798memory.
799
800=item ecb_poke_be_u16_u (void *ptr, uint_fast16_t v)
801
802=item ecb_poke_be_u32_u (void *ptr, uint_fast32_t v)
803
804=item ecb_poke_be_u64_u (void *ptr, uint_fast64_t v)
805
806=item ecb_poke_le_u16_u (void *ptr, uint_fast16_t v)
807
808=item ecb_poke_le_u32_u (void *ptr, uint_fast32_t v)
809
810=item ecb_poke_le_u64_u (void *ptr, uint_fast64_t v)
811
812Like above, but additionally convert from host byte order to big endian
813(C<be>) or little endian (C<le>) byte order while doing so.
814
815=back
816
817In C++ the following additional functions are supported:
818
819=over 4
820
821=item T ecb_peek (const void *ptr)
822
823=item T ecb_peek_be (const void *ptr)
824
825=item T ecb_peek_le (const void *ptr)
826
827=item T ecb_peek_u (const void *ptr)
828
829=item T ecb_peek_be_u (const void *ptr)
830
831=item T ecb_peek_le_u (const void *ptr)
832
833Similarly to their C counterparts, these functions load an unsigned 8, 16,
83432 or 64 bit value from memory, with optional conversion from big/little
835endian.
836
837Since the type cannot be deduced, it has top be specified explicitly, e.g.
838
839 uint_fast16_t v = ecb_peek<uint16_t> (ptr);
840
841C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
842
843Unlike their C counterparts, these functions support 8 bit quantities
844(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
845all of which hopefully makes them more useful in generic code.
846
847=item ecb_poke (void *ptr, T v)
848
849=item ecb_poke_be (void *ptr, T v)
850
851=item ecb_poke_le (void *ptr, T v)
852
853=item ecb_poke_u (void *ptr, T v)
854
855=item ecb_poke_be_u (void *ptr, T v)
856
857=item ecb_poke_le_u (void *ptr, T v)
858
859Again, similarly to their C counterparts, these functions store an
860unsigned 8, 16, 32 or z64 bit value to memory, with optional conversion to
861big/little endian.
862
863C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
864
865Unlike their C counterparts, these functions support 8 bit quantities
866(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
867all of which hopefully makes them more useful in generic code.
684 868
685=back 869=back
686 870
687=head2 FLOATING POINT FIDDLING 871=head2 FLOATING POINT FIDDLING
688 872

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