Data update

Task/Base64-decode-data/REXX/base64-decode-data-1.rexx

@@ -0,0 +1,20 @@
+z= 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
+do i=1 to 64
+  bs.i=x2b(d2x(i-1))
+  c=substr(z,i,1)
+  ds.c=right(bs.i,6,0)
+  End
+e='YW55IGNhcm5hbCBwbGVhc3VyZS4'
+r=''
+ec=e
+Do While ec<>''
+  Parse Var ec c +1 ec
+  r=r||ds.c
+  End
+res=''
+Do while r<>''
+  Parse Var r x +8 r
+  res=res||x2c(b2x(x))
+  End
+Say 'Input:   >'e'<'
+Say 'decoded: >'res'<'

Task/Base64-decode-data/REXX/base64-decode-data-2.rexx

@@ -0,0 +1,56 @@
+-- 3 Oct 2025
+include Setting
+signal off notready
+
+say 'BASE64 DECODE DATA'
+say version
+say
+call Task1 'TWFueSBoYW5kcyBtYWtlIGxpZ2h0IHdvcmsu'
+call Task1 'TWFu'
+call Task1 'TWE='
+call Task1 'TQ=='
+call Task1 'YW55IGNhcm5hbCBwbGVhc3VyZS4='
+call Task2
+exit
+
+Task1:
+procedure
+parse arg xx
+say 'Encoded ' xx
+say 'Original' Decode64(xx)
+say
+return
+
+Task2:
+procedure
+in='favicon.dat'; out='favcopy.ico'
+rr=Decode64(Charin(in,1,30000))
+call Charout out,rr,1
+return
+
+Decode64:
+procedure
+parse arg xx
+-- Alphabet
+a='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
+lx=Length(xx)
+rr=''
+-- Loop thru encoded characters
+do i=1 to lx
+   c=Substr(xx,i,1)
+-- If padding, discard 2 bits
+   if c='=' then do
+      rr=Left(rr,Length(rr)-2)
+      iterate i
+   end
+-- Find position in alphabet
+   p=Pos(c,a)-1
+-- Convert to bits and take last 6
+   b=Right(0000||X2b(D2x(p)),6)
+-- Append
+   rr||=b
+end
+-- Convert to character
+return X2c(B2x(rr))
+
+include Abend