xref: /freebsd/crypto/openssl/doc/man3/OPENSSL_load_u16_le.pod (revision e7be843b4a162e68651d3911f0357ed464915629)
1*e7be843bSPierre Pronchery=pod
2*e7be843bSPierre Pronchery
3*e7be843bSPierre Pronchery=head1 NAME
4*e7be843bSPierre Pronchery
5*e7be843bSPierre ProncheryOPENSSL_load_u16_le, OPENSSL_load_u16_be, OPENSSL_load_u32_le,
6*e7be843bSPierre ProncheryOPENSSL_load_u32_be, OPENSSL_load_u64_le, OPENSSL_load_u64_be,
7*e7be843bSPierre ProncheryOPENSSL_store_u16_le, OPENSSL_store_u16_be,
8*e7be843bSPierre ProncheryOPENSSL_store_u32_le, OPENSSL_store_u32_be,
9*e7be843bSPierre ProncheryOPENSSL_store_u64_le, OPENSSL_store_u64_be -
10*e7be843bSPierre ProncheryRead and write unsigned 16, 32 and 64-bit integers in a specific byte order
11*e7be843bSPierre Pronchery
12*e7be843bSPierre Pronchery=head1 SYNOPSIS
13*e7be843bSPierre Pronchery
14*e7be843bSPierre Pronchery    #include <openssl/byteorder.h>
15*e7be843bSPierre Pronchery
16*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u16_le(
17*e7be843bSPierre Pronchery        unsigned char *out, uint16_t val);
18*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u16_be(
19*e7be843bSPierre Pronchery        unsigned char *out, uint16_t val);
20*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u32_le(
21*e7be843bSPierre Pronchery        unsigned char *out, uint32_t val);
22*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u32_be(
23*e7be843bSPierre Pronchery        unsigned char *out, uint32_t val);
24*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u64_le(
25*e7be843bSPierre Pronchery        unsigned char *out, uint64_t val);
26*e7be843bSPierre Pronchery    static ossl_inline unsigned char *OPENSSL_store_u64_be(
27*e7be843bSPierre Pronchery        unsigned char *out, uint64_t val);
28*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u16_le(
29*e7be843bSPierre Pronchery        uint16_t *val, const unsigned char *in);
30*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u16_be(
31*e7be843bSPierre Pronchery        uint16_t *val, const unsigned char *in);
32*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u32_le(
33*e7be843bSPierre Pronchery        uint32_t *val, const unsigned char *in);
34*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u32_be(
35*e7be843bSPierre Pronchery        uint32_t *val, const unsigned char *in);
36*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u64_le(
37*e7be843bSPierre Pronchery        uint64_t *val, const unsigned char *in);
38*e7be843bSPierre Pronchery    static ossl_inline const unsigned char *OPENSSL_load_u64_be(
39*e7be843bSPierre Pronchery        uint64_t *val, const unsigned char *in);
40*e7be843bSPierre Pronchery
41*e7be843bSPierre Pronchery=head1 DESCRIPTION
42*e7be843bSPierre Pronchery
43*e7be843bSPierre ProncheryThese functions read and write 16, 32 and 64 bit unsigned integers in a
44*e7be843bSPierre Proncheryspecified byte order.
45*e7be843bSPierre ProncheryThe C<_be> functions use big-endian byte order, while the C<_le> functions use
46*e7be843bSPierre Proncherylittle-endian byte order.
47*e7be843bSPierre ProncheryThey're implemented directly in the header file, and declared static.  When the
48*e7be843bSPierre Proncherycompiler supports inline functions, they're also declared inline.
49*e7be843bSPierre ProncheryAn optimising compiler will often convert these to just one or two machine
50*e7be843bSPierre Proncheryinstructions: a load or store with a possible byte swap.
51*e7be843bSPierre Pronchery
52*e7be843bSPierre ProncheryThe C<load> functions write the decoded integer value at the address pointed to
53*e7be843bSPierre Proncheryby I<val>, which must be a valid (possibly suitably aligned) address of an
54*e7be843bSPierre Proncheryobject of the appropriate type.
55*e7be843bSPierre ProncheryThe C<store> functions write the encoding of I<val> at the address pointed to
56*e7be843bSPierre Proncheryby I<out>.
57*e7be843bSPierre Pronchery
58*e7be843bSPierre ProncheryFor convenience, these functions return the updated input or output pointer,
59*e7be843bSPierre Proncherymaking it easy to continue reading or writing more data at the next memory
60*e7be843bSPierre Proncherylocation.
61*e7be843bSPierre Pronchery
62*e7be843bSPierre ProncheryNo bounds checks are performed, the caller is responsible for making sure that
63*e7be843bSPierre Proncherythe input or output buffers are sufficiently large for the requested read or
64*e7be843bSPierre Proncherywrite.
65*e7be843bSPierre Pronchery
66*e7be843bSPierre Pronchery=head1 RETURN VALUES
67*e7be843bSPierre Pronchery
68*e7be843bSPierre ProncheryAll these functions return the next memory address following the last byte
69*e7be843bSPierre Proncherywritten or read.
70*e7be843bSPierre Pronchery
71*e7be843bSPierre Pronchery=head1 HISTORY
72*e7be843bSPierre Pronchery
73*e7be843bSPierre ProncheryThese functions were added in OpenSSL 3.5.
74*e7be843bSPierre Pronchery
75*e7be843bSPierre Pronchery=head1 COPYRIGHT
76*e7be843bSPierre Pronchery
77*e7be843bSPierre ProncheryCopyright 2025 The OpenSSL Project Authors. All Rights Reserved.
78*e7be843bSPierre Pronchery
79*e7be843bSPierre ProncheryLicensed under the Apache License 2.0 (the "License").  You may not use
80*e7be843bSPierre Proncherythis file except in compliance with the License.  You can obtain a copy
81*e7be843bSPierre Proncheryin the file LICENSE in the source distribution or at
82*e7be843bSPierre ProncheryL<https://www.openssl.org/source/license.html>.
83*e7be843bSPierre Pronchery
84*e7be843bSPierre Pronchery=cut
85