June 2018 Update

Task/URL-decoding/UNIX-Shell/url-decoding-3.sh

@@ -0,0 +1,64 @@
+function urldecode
+{
+        typeset encoded=$1 decoded= rest= c= c1= c2=
+        typeset rest2= bug='rest2=${rest}'
+
+        if [[ -z ${BASH_VERSION:-} ]]; then
+                typeset -i16 hex=0; typeset -i8 oct=0
+
+                # bug /usr/bin/sh HP-UX 11.00
+                typeset _encoded='xyz%26xyz'
+                rest="${_encoded#?}"
+                c="${_encoded%%${rest}}"
+                if (( ${#c} != 1 )); then
+                        typeset qm='????????????????????????????????????????????????????????????????????????'
+                        typeset bug='(( ${#rest} > 0 )) && typeset -L${#rest} rest2="${qm}" || rest2=${rest}'
+                fi
+        fi
+
+	rest="${encoded#?}"
+	eval ${bug}
+	c="${encoded%%${rest2}}"
+	encoded="${rest}"
+
+	while [[ -n ${c} ]]; do
+		if [[ ${c} = '%' ]]; then
+			rest="${encoded#?}"
+			eval ${bug}
+			c1="${encoded%%${rest2}}"
+			encoded="${rest}"
+
+			rest="${encoded#?}"
+			eval ${bug}
+			c2="${encoded%%${rest2}}"
+			encoded="${rest}"
+
+			if [[ -z ${c1} || -z ${c2} ]]; then
+				c="%${c1}${c2}"
+				echo "WARNING: invalid % encoding: ${c}" >&2
+			elif [[ -n ${BASH_VERSION:-} ]]; then
+				c="\\x${c1}${c2}"
+				c=$(\echo -e "${c}")
+			else
+				hex="16#${c1}${c2}"; oct=hex
+				c="\\0${oct#8\#}"
+				c=$(print -- "${c}")
+			fi
+		elif [[ ${c} = '+' ]]; then
+			c=' '
+		fi
+
+		decoded="${decoded}${c}"
+
+		rest="${encoded#?}"
+		eval ${bug}
+		c="${encoded%%${rest2}}"
+		encoded="${rest}"
+	done
+
+	if [[ -n ${BASH_VERSION:-} ]]; then
+		\echo -E "${decoded}"
+	else
+		print -r -- "${decoded}"
+	fi
+}