Data commit

Task/URL-decoding/XPL0/url-decoding.xpl0

@@ -0,0 +1,23 @@
+code Text=12;
+string 0;               \use zero-terminated strings
+
+func Decode(S0);        \Decode URL string and return its address
+char S0;
+char S1(80);            \BEWARE: very temporary string space returned
+int  C, N, I, J;
+[I:= 0;  J:= 0;
+repeat  C:= S0(I);  I:= I+1;                    \get char
+        if C=^% then                            \convert hex to char
+                [C:= S0(I);  I:= I+1;
+                if C>=^a then C:= C & ~$20;     \convert to uppercase
+                N:= C - (if C<=^9 then ^0 else ^A-10);
+                C:= S0(I);  I:= I+1;
+                if C>=^a then C:= C & ~$20;
+                C:= N*16 + C - (if C<=^9 then ^0 else ^A-10);
+                ];
+        S1(J):= C;  J:= J+1;                    \put char in output string
+until   C=0;
+return S1;
+];
+
+Text(0, Decode("http%3A%2F%2Ffoo%20bar%2f"))