[ViewVC] Diff of: cvs/libecb/ecb.pod

Comparing libecb/ecb.pod (file contents):
Revision 1.67 by root, Fri Feb 20 15:53:36 2015 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
61	ecb.h makes sure that the following types are defined (in the expected way):	61	ecb.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
67	The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this	73	The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this
68	platform (currently C<4> or C<8>) and can be used in preprocessor	74	platform (currently C<4> or C<8>) and can be used in preprocessor
69	expressions.	75	expressions.
70		76
71	For C<ptrdiff_t> and C<size_t> use C<stddef.h>.	77	For C<ptrdiff_t> and C<size_t> use C<stddef.h>/C<cstddef>.
72		78
73	=head2 LANGUAGE/ENVIRONMENT/COMPILER VERSIONS	79	=head2 LANGUAGE/ENVIRONMENT/COMPILER VERSIONS
74		80
75	All the following symbols expand to an expression that can be tested in	81	All the following symbols expand to an expression that can be tested in
76	preprocessor instructions as well as treated as a boolean (use C<!!> to	82	preprocessor instructions as well as treated as a boolean (use C<!!> to
…		…
89	9899:1999) or any later version, while not claiming to be C++.	95	9899:1999) or any later version, while not claiming to be C++.
90		96
91	Note that later versions (ECB_C11) remove core features again (for	97	Note that later versions (ECB_C11) remove core features again (for
92	example, variable length arrays).	98	example, variable length arrays).
93		99
94	=item ECB_C11	100	=item ECB_C11, ECB_C17
95		101
96	True if the implementation claims to be compliant to C11 (ISO/IEC	102	True if the implementation claims to be compliant to C11/C17 (ISO/IEC
97	9899:2011) or any later version, while not claiming to be C++.	103	9899:2011, :20187) or any later version, while not claiming to be C++.
98		104
99	=item ECB_CPP	105	=item ECB_CPP
100		106
101	True if the implementation defines the C<__cplusplus__> macro to a true	107	True if the implementation defines the C<__cplusplus__> macro to a true
102	value, which is typically true for C++ compilers.	108	value, which is typically true for C++ compilers.
103		109
104	=item ECB_CPP11	110	=item ECB_CPP11, ECB_CPP14, ECB_CPP17
105		111
106	True if the implementation claims to be compliant to ISO/IEC 14882:2011	112	True if the implementation claims to be compliant to C++11/C++14/C++17
107	(C++11) or any later version.	113	(ISO/IEC 14882:2011, :2014, :2017) or any later version.
108		114
109	=item ECB_GCC_VERSION (major, minor)	115	=item ECB_GCC_VERSION (major, minor)
110		116
111	Expands to a true value (suitable for testing in by the preprocessor)	117	Expands to a true value (suitable for testing in by the preprocessor)
112	if the compiler used is GNU C and the version is the given version, or	118	if the compiler used is GNU C and the version is the given version, or
…		…
248	used instead of a generic depreciation message when the object is being	254	used instead of a generic depreciation message when the object is being
249	used.	255	used.
250		256
251	=item ecb_inline	257	=item ecb_inline
252		258
253	Expands either to C<static inline> or to just C<static>, if inline	259	Expands either to (a compiler-specific equivalent of) C<static inline> or
254	isn't supported. It should be used to declare functions that should be	260	to just C<static>, if inline isn't supported. It should be used to declare
255	inlined, for code size or speed reasons.	261	functions that should be inlined, for code size or speed reasons.
256		262
257	Example: inline this function, it surely will reduce codesize.	263	Example: inline this function, it surely will reduce codesize.
258		264
259	ecb_inline int	265	ecb_inline int
260	negmul (int a, int b)	266	negmul (int a, int b)
…		…
401	=back	407	=back
402		408
403	=head2 OPTIMISATION HINTS	409	=head2 OPTIMISATION HINTS
404		410
405	=over 4	411	=over 4
		412
		413	=item ECB_OPTIMIZE_SIZE
		414
		415	Is C<1> when the compiler optimizes for size, C<0> otherwise. This symbol
		416	can also be defined before including F<ecb.h>, in which case it will be
		417	unchanged.
406		418
407	=item bool ecb_is_constant (expr)	419	=item bool ecb_is_constant (expr)
408		420
409	Returns true iff the expression can be deduced to be a compile-time	421	Returns true iff the expression can be deduced to be a compile-time
410	constant, and false otherwise.	422	constant, and false otherwise.
…		…
656		668
657	These functions return the value of the 16-bit (32-bit, 64-bit) value	669	These functions return the value of the 16-bit (32-bit, 64-bit) value
658	C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in	670	C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in
659	C<ecb_bswap32>).	671	C<ecb_bswap32>).
660		672
		673	=item T ecb_bswap (T x) [C++]
		674
		675	For C++, an additional generic bswap function is provided. It supports
		676	C<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)
…		…
682	to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on	699	to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on
683	x86).	700	x86).
684		701
685	=back	702	=back
686		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
		720	Convert an unsigned 16, 32 or 64 bit value from big or little endian to host byte order.
		721
		722	The naming convention is C<ecb_>(C<be>\|C<le>)C<_u>C<16\|32\|64>C<_to_host>,
		723	where 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
		737	Like above, but converts I<from> host byte order to the specified
		738	endianness.
		739
		740	=back
		741
		742	In 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
		754	These work like their C counterparts, above, but use templates for the
		755	type, which make them useful in generic code.
		756
		757	C<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
		759	again can be useful in generic code).
		760
		761	=head2 UNALIGNED LOAD/STORE
		762
		763	These 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
		773	These functions load an unaligned, unsigned 16, 32 or 64 bit value from
		774	memory.
		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
		788	Like above, but additionally convert from big endian (C<be>) or little
		789	endian (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
		797	These functions store an unaligned, unsigned 16, 32 or 64 bit value to
		798	memory.
		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
		812	Like 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
		817	In 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
		833	Similarly to their C counterparts, these functions load an unsigned 8, 16,
		834	32 or 64 bit value from memory, with optional conversion from big/little
		835	endian.
		836
		837	Since 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
		841	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
		842
		843	Unlike their C counterparts, these functions support 8 bit quantities
		844	(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
		845	all 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
		859	Again, similarly to their C counterparts, these functions store an
		860	unsigned 8, 16, 32 or z64 bit value to memory, with optional conversion to
		861	big/little endian.
		862
		863	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
		864
		865	Unlike their C counterparts, these functions support 8 bit quantities
		866	(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
		867	all of which hopefully makes them more useful in generic code.
		868
		869	=back
		870
687	=head2 FLOATING POINT FIDDLING	871	=head2 FLOATING POINT FIDDLING
688		872
689	=over 4	873	=over 4
690		874
691	=item ECB_INFINITY	875	=item ECB_INFINITY [-UECB_NO_LIBM]
692		876
693	Evaluates to positive infinity if supported by the platform, otherwise to	877	Evaluates to positive infinity if supported by the platform, otherwise to
694	a truly huge number.	878	a truly huge number.
695		879
696	=item ECB_NAN	880	=item ECB_NAN [-UECB_NO_LIBM]
697		881
698	Evaluates to a quiet NAN if supported by the platform, otherwise to	882	Evaluates to a quiet NAN if supported by the platform, otherwise to
699	C<ECB_INFINITY>.	883	C<ECB_INFINITY>.
700		884
701	=item float ecb_ldexpf (float x, int exp)	885	=item float ecb_ldexpf (float x, int exp) [-UECB_NO_LIBM]
702		886
703	Same as C<ldexpf>, but always available.	887	Same as C<ldexpf>, but always available.
704		888
		889	=item uint32_t ecb_float_to_binary16 (float x) [-UECB_NO_LIBM]
		890
705	=item uint32_t ecb_float_to_binary32 (float x) [-UECB_NO_LIBM]	891	=item uint32_t ecb_float_to_binary32 (float x) [-UECB_NO_LIBM]
706		892
707	=item uint64_t ecb_double_to_binary64 (double x) [-UECB_NO_LIBM]	893	=item uint64_t ecb_double_to_binary64 (double x) [-UECB_NO_LIBM]
708		894
709	These functions each take an argument in the native C<float> or C<double>	895	These functions each take an argument in the native C<float> or C<double>
710	type and return the IEEE 754 bit representation of it.	896	type and return the IEEE 754 bit representation of it (binary16/half,
		897	binary32/single or binary64/double precision).
711		898
712	The bit representation is just as IEEE 754 defines it, i.e. the sign bit	899	The bit representation is just as IEEE 754 defines it, i.e. the sign bit
713	will be the most significant bit, followed by exponent and mantissa.	900	will be the most significant bit, followed by exponent and mantissa.
714		901
715	This function should work even when the native floating point format isn't	902	This function should work even when the native floating point format isn't
…		…
719		906
720	On all modern platforms (where C<ECB_STDFP> is true), the compiler should	907	On all modern platforms (where C<ECB_STDFP> is true), the compiler should
721	be able to optimise away this function completely.	908	be able to optimise away this function completely.
722		909
723	These functions can be helpful when serialising floats to the network - you	910	These functions can be helpful when serialising floats to the network - you
724	can serialise the return value like a normal uint32_t/uint64_t.	911	can serialise the return value like a normal uint16_t/uint32_t/uint64_t.
725		912
726	Another use for these functions is to manipulate floating point values	913	Another use for these functions is to manipulate floating point values
727	directly.	914	directly.
728		915
729	Silly example: toggle the sign bit of a float.	916	Silly example: toggle the sign bit of a float.
…		…
736		923
737	=item float ecb_binary16_to_float (uint16_t x) [-UECB_NO_LIBM]	924	=item float ecb_binary16_to_float (uint16_t x) [-UECB_NO_LIBM]
738		925
739	=item float ecb_binary32_to_float (uint32_t x) [-UECB_NO_LIBM]	926	=item float ecb_binary32_to_float (uint32_t x) [-UECB_NO_LIBM]
740		927
741	=item double ecb_binary32_to_double (uint64_t x) [-UECB_NO_LIBM]	928	=item double ecb_binary64_to_double (uint64_t x) [-UECB_NO_LIBM]
742		929
743	The reverse operation of the previous function - takes the bit	930	The reverse operation of the previous function - takes the bit
744	representation of an IEEE binary16, binary32 or binary64 number and	931	representation of an IEEE binary16, binary32 or binary64 number (half,
745	converts it to the native C<float> or C<double> format.	932	single or double precision) and converts it to the native C<float> or
		933	C<double> format.
746		934
747	This function should work even when the native floating point format isn't	935	This function should work even when the native floating point format isn't
748	IEEE compliant, of course at a speed and code size penalty, and of course	936	IEEE compliant, of course at a speed and code size penalty, and of course
749	also within reasonable limits (it tries to convert normals and denormals,	937	also within reasonable limits (it tries to convert normals and denormals,
750	and might be lucky for infinities, and with extraordinary luck, also for	938	and might be lucky for infinities, and with extraordinary luck, also for
751	negative zero).	939	negative zero).
752		940
753	On all modern platforms (where C<ECB_STDFP> is true), the compiler should	941	On all modern platforms (where C<ECB_STDFP> is true), the compiler should
754	be able to optimise away this function completely.	942	be able to optimise away this function completely.
		943
		944	=item uint16_t ecb_binary32_to_binary16 (uint32_t x)
		945
		946	=item uint32_t ecb_binary16_to_binary32 (uint16_t x)
		947
		948	Convert a IEEE binary32/single precision to binary16/half format, and vice
		949	versa, handling all details (round-to-nearest-even, subnormals, infinity
		950	and NaNs) correctly.
		951
		952	These are functions are available under C<-DECB_NO_LIBM>, since
		953	they do not rely on the platform floating point format. The
		954	C<ecb_float_to_binary16> and C<ecb_binary16_to_float> functions are
		955	usually what you want.
755		956
756	=back	957	=back
757		958
758	=head2 ARITHMETIC	959	=head2 ARITHMETIC
759		960
…		…
840	dependencies on the math library (usually called F<-lm>) - these are	1041	dependencies on the math library (usually called F<-lm>) - these are
841	marked with [-UECB_NO_LIBM].	1042	marked with [-UECB_NO_LIBM].
842		1043
843	=back	1044	=back
844		1045
		1046	=head1 UNDOCUMENTED FUNCTIONALITY
845		1047
		1048	F<ecb.h> is full of undocumented functionality as well, some of which is
		1049	intended to be internal-use only, some of which we forgot to document, and
		1050	some of which we hide because we are not sure we will keep the interface
		1051	stable.
		1052
		1053	While you are welcome to rummage around and use whatever you find useful
		1054	(we can't stop you), keep in mind that we will change undocumented
		1055	functionality in incompatible ways without thinking twice, while we are
		1056	considerably more conservative with documented things.
		1057
		1058	=head1 AUTHORS
		1059
		1060	C<libecb> is designed and maintained by:
		1061
		1062	Emanuele Giaquinta <e.giaquinta@glauco.it>
		1063	Marc Alexander Lehmann <schmorp@schmorp.de>
		1064
		1065

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Comparing libecb/ecb.pod (file contents): Revision 1.67 by root, Fri Feb 20 15:53:36 2015 UTC vs. Revision 1.76 by root, Mon Jan 20 13:13:56 2020 UTC

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Comparing libecb/ecb.pod (file contents):
Revision 1.67 by root, Fri Feb 20 15:53:36 2015 UTC vs.
Revision 1.76 by root, Mon Jan 20 13:13:56 2020 UTC