d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add inline functions {be,le}{16,32,64}{enc,dec}() for encoding decoding

Browse Source 
into byte strings of unknown alignment.
This commit is contained in:
Poul-Henning Kamp 2003-04-03 08:58:04 +00:00
parent 9f88fdfb88
commit 21ee4ab688
2 changed files with 147 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
share/man/man9/byteorder.9
View File

@ -41,6 +41,9 @@
.Nm le32toh ,
.Nm le64toh
.Nd convert values between big endian, little endian, and host byte order
.Pp
.Nm {be,le}{16,32,64}{enc,dec}
.Nd encode and decode big or little endian values to and from byte strings
.Sh SYNOPSIS
.In sys/endian.h
.Ft uint16_t
@ -73,6 +76,30 @@
.Fn le32toh "uint32_t little32"
.Ft uint64_t
.Fn le64toh "uint64_t little64"
.Ft uint16_t
.Fn be16dec "const void *"
.Ft uint32_t
.Fn be32dec "const void *"
.Ft uint64_t
.Fn be64dec "const void *"
.Ft uint16_t
.Fn le16dec "const void *"
.Ft uint32_t
.Fn le32dec "const void *"
.Ft uint64_t
.Fn le64dec "const void *"
.Ft void
.Fn be16enc "void *, uint16_t"
.Ft void
.Fn be32enc "void *, uint32_t"
.Ft void
.Fn be64enc "void *, uint64_t"
.Ft void
.Fn le16enc "void *, uint16_t"
.Ft void
.Fn le32enc "void *, uint32_t"
.Ft void
.Fn le64enc "void *, uint64_t"
.Sh DESCRIPTION
The
.Fn bswap16 ,
@ -118,11 +145,22 @@ and
functions return a integer in the system's native
byte order converted to little endian byte order.
The return value will be the same as the argument on little endian systems.
.Pp
The
.Fn {be,le}{16,32,64}{enc,dec}
functions encode and decode integers to/from byte strings on any alignment
in big/little endian format.
.Sh SEE ALSO
.Xr byteorder 3
.Sh HISTORY
These functions first appeared in
The hto* and toh* functions first appeared in
.Fx 5.0 ,
and were originally developed by the
.Nx
project.
.Pp
The
.Fn {be,le}{16,32,64}{enc,dec}
Functions first appeared in
.Fx 5.1 .

108
sys/sys/endian.h
View File

@ -89,4 +89,112 @@ typedef __uint64_t uint64_t;
#define le64toh(x) bswap64((x))
#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
/* Alignment-agnostic encode/decode bytestream to/from little/big endian. */
static __inline uint16_t
be16dec(const void *pp)
{
u_char const *p = pp;
return ((p[0] << 8) | p[1]);
}
static __inline uint32_t
be32dec(const void *pp)
{
u_char const *p = pp;
return ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
}
static __inline uint64_t
be64dec(const void *pp)
{
u_char const *p = pp;
return (((uint64_t)be32dec(p) << 32) | be32dec(p + 4));
}
static __inline uint16_t
le16dec(const void *pp)
{
u_char const *p = pp;
return ((p[1] << 8) | p[0]);
}
static __inline uint32_t
le32dec(const void *pp)
{
u_char const *p = pp;
return ((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]);
}
static __inline uint64_t
le64dec(const void *pp)
{
u_char const *p = pp;
return (((uint64_t)be32dec(p + 4) << 32) | be32dec(p));
}
static __inline void
be16enc(void *pp, uint16_t u)
{
u_char *p = pp;
p[0] = (u >> 8) & 0xff;
p[1] = u & 0xff;
}
static __inline void
be32enc(void *pp, uint32_t u)
{
u_char *p = pp;
p[0] = (u >> 24) & 0xff;
p[1] = (u >> 16) & 0xff;
p[2] = (u >> 8) & 0xff;
p[3] = u & 0xff;
}
static __inline void
be64enc(void *pp, uint64_t u)
{
u_char *p = pp;
be32enc(p, u >> 32);
be32enc(p + 4, u & 0xffffffff);
}
static __inline void
le16enc(void *pp, uint16_t u)
{
u_char *p = pp;
p[0] = u & 0xff;
p[1] = (u >> 8) & 0xff;
}
static __inline void
le32enc(void *pp, uint32_t u)
{
u_char *p = pp;
p[0] = u & 0xff;
p[1] = (u >> 8) & 0xff;
p[2] = (u >> 16) & 0xff;
p[3] = (u >> 24) & 0xff;
}
static __inline void
le64enc(void *pp, uint64_t u)
{
u_char *p = pp;
be32enc(p, u & 0xffffffff);
be32enc(p + 4, u >> 32);
}
#endif /* _SYS_ENDIAN_H_ */