rem, common: recognize multi-valued lines

For muliple values we simply concatenate the input with newlines.
None of the properties we implement so far need special
considerations in this regard.

1 files changed, 14 insertions, 0 deletions

diff --git a/common.lua b/common.lua
index 6afde62..2c68aee 100644
--- a/common.lua
+++ b/common.lua
@@ -24,6 +24,7 @@ local set_verbosity = function (n) verboselvl = n end
 
 local trim_whitespace
 local unescape_string
+local internalize_value
 do
   local P                 = lpeg.P
   local S                 = lpeg.S
@@ -41,10 +42,22 @@ do
                           + (P"\\v" / "\v")
   local p_unescape        = Cs ((p_escape_char + 1)^0)
 
+  --[[--
+
+    rfc2445, sec. 4.1.2: Properties can have multiple values, separated by a
+    literal comma, thus text commas are escaped.
+
+  --]]--
+  local p_value_char      = (  p_escape_char
+                             + P"\\," / ","
+                             + P"," / "\n")
+  local p_value           = Cs ((p_value_char + 1)^0)
+
   local lpegmatch         = lpeg.match
 
   trim_whitespace = function (s) return lpegmatch (p_ws_drop , s) end
   unescape_string = function (s) return lpegmatch (p_unescape, s) end
+  internalize_value = function (s) return lpegmatch (p_value, s) end
 end
 
 return
@@ -55,5 +68,6 @@ return
   , set_verbosity         = set_verbosity
   , trim_whitespace       = trim_whitespace
   , unescape_string       = unescape_string
+  , internalize_value     = internalize_value
   }