bugfix: escape, again

src/awk/get.awk

@@ -3,6 +3,40 @@
 ##
 ## @assign field: Field name
 
+# Unescape string
+#
+# @local variables: i, c, c2, res
+# @input str: String
+# @return: Unescaped string
+function unescape(str,    i, c, c2, res) {
+  for(i=1; i<=length(str);i++) {
+    c = substr(str, i, 1)
+    if (c != "\\") {
+      res = res c
+      continue
+    }
+    i++
+    c2 = substr(str, i, 1)
+    if (c2 == "n" || c2 == "N") {
+      res = res "\n"
+      continue
+    }
+    # Alternatively, c2 is "\\" or "," or ";". In each case, append res with
+    # c2. If the strings has been escaped correctly, then the character c2
+    # cannot be anything else. To be fail-safe, simply append res with c2.
+    res = res c2
+  }
+  return res
+}
+
+# Isolate content part of an iCalendar line, and unescape.
+#
+# @input str: String
+# @return: Unescaped content part
+function getcontent(str) {
+  return unescape(substr(str, index(str, ":") + 1))
+}
+
 # AWK program
 BEGIN              { FS = ":"; regex = "^" field }
 /^BEGIN:VEVENT$/   { inside = 1 }
@@ -13,11 +47,5 @@ $0 ~ regex         { content = $0; next }
 END {
   if (!inside) { exit }
   # Process content line
-  content = substr(content, index(content, ":") + 1)
-  gsub("\\\\n",    "\n", content)
-  gsub("\\\\N",    "\n", content)
-  gsub("\\\\,",    ",",  content)
-  gsub("\\\\;",    ";",  content)
-  gsub("\\\\\\\\", "\\", content)
-  print content
+  print getcontent(content)
 }