#
#
# Nimrod's Runtime Library
# (c) Copyright 2012 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
## This module contains helpers that deal with different byte orders
## (`endian`:idx:).
proc swapEndian64*(outp, inp: pointer) =
## copies `inp` to `outp` swapping bytes. Both buffers are supposed to
## contain at least 8 bytes.
var i = cast[cstring](inp)
var o = cast[cstring](outp)
o[0] = i[7]
o[1] = i[6]
o[2] = i[5]
o[3] = i[4]
o[4] = i[3]
o[5] = i[2]
o[6] = i[1]
o[7] = i[0]
proc swapEndian32*(outp, inp: pointer) =
## copies `inp` to `outp` swapping bytes. Both buffers are supposed to
## contain at least 4 bytes.
var i = cast[cstring](inp)
var o = cast[cstring](outp)
o[0] = i[3]
o[1] = i[2]
o[2] = i[1]
o[3] = i[0]
when system.cpuEndian == bigEndian:
proc littleEndian64*(outp, inp: pointer) {.inline.} = swapEndian64(outp, inp)
proc littleEndian32*(outp, inp: pointer) {.inline.} = swapEndian32(outp, inp)
proc bigEndian64*(outp, inp: pointer) {.inline.} = copyMem(outp, inp, 8)
proc bigEndian32*(outp, inp: pointer) {.inline.} = copyMem(outp, inp, 4)
else:
proc littleEndian64*(outp, inp: pointer) {.inline.} = copyMem(outp, inp, 8)
proc littleEndian32*(outp, inp: pointer) {.inline.} = copyMem(outp, inp, 4)
proc bigEndian64*(outp, inp: pointer) {.inline.} = swapEndian64(outp, inp)
proc bigEndian32*(outp, inp: pointer) {.inline.} = swapEndian32(outp, inp)