1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
|
# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
# KI_ENCODE -- Encode an integer into the indicated number of chars for
# transmission between machines via a byte stream.
procedure ki_encode (data, str, nchars)
long data # data value to be encoded
char str[nchars] # output chars
int nchars # number of chars to be encoded
int i
long v, nv
begin
v = abs (data)
do i = 1, nchars {
nv = v / 128
str[i] = v - (nv * 128)
v = nv
}
if (data < 0)
if (str[1] == 0)
str[1] = -128
else
str[1] = -str[1]
end
# KI_DECODE -- Decode the long integer value encoded by ki_encode, returning
# the long integer value as the function value.
long procedure ki_decode (str, nchars)
char str[ARB] # string to be decoded
int nchars # number of chars to decode
bool neg
int pow, i
long sum
begin
sum = str[1]
neg = (sum < 0)
if (neg)
if (sum == -128)
sum = 0
else
sum = -sum
pow = 1
do i = 2, nchars {
pow = pow * 128
sum = sum + (str[i] * pow)
}
if (neg)
return (-sum)
else
return (sum)
end
|