skin_engine: rework the parser to be closer to the langauge grammar.

The parser was unconditionally scanning things which it thought
were conditional/enum lists (or tag arg lists) when they couldn't
possibly be (i.e < inside a param which should be valid).

This change fixes it (i.e %?and(%if(%pv, <, -50), %if(%mp, > 1))
is perfectly valid now.

This *may* break your exsiting skins if you were using %if with < or >

Change-Id: Ibcb42bc6bb78908f79de024b61276b91b1ce02a0
Reviewed-on: http://gerrit.rockbox.org/214
Reviewed-by: Thomas Martitz <kugel@rockbox.org>

1 files changed, 5 insertions, 60 deletions

diff --git a/lib/skin_parser/skin_parser.c b/lib/skin_parser/skin_parser.c
index a81bcde..44a1c03 100644
--- a/lib/skin_parser/skin_parser.c
+++ b/lib/skin_parser/skin_parser.c
@@ -182,26 +182,12 @@ static struct skin_element* skin_parse_viewport(const char** document)
             }
             else if(*cursor == TAGSYM)
             {
-                /* A ';' directly after a '%' doesn't count */
-                cursor ++;
-
-                if(*cursor == '\0')
-                    break;
-
-                cursor++;
+                skip_tag(&cursor);
             }
             else if(*cursor == COMMENTSYM)
             {
                 skip_comment(&cursor);
             }
-            else if(*cursor == ARGLISTOPENSYM)
-            {
-                skip_arglist(&cursor);
-            }
-            else if(*cursor == ENUMLISTOPENSYM)
-            {
-                skip_enumlist(&cursor);
-            }
             else
             {
                 /* Advancing the cursor as normal */
@@ -445,20 +431,9 @@ static struct skin_element* skin_parse_sublines_optional(const char** document,
         {
             skip_comment(&cursor);
         }
-        else if(*cursor == ENUMLISTOPENSYM)
-        {
-            skip_enumlist(&cursor);
-        }
-        else if(*cursor == ARGLISTOPENSYM)
-        {
-            skip_arglist(&cursor);
-        }
         else if(*cursor == TAGSYM)
         {
-            cursor++;
-            if(*cursor == '\0' || *cursor == '\n')
-                break;
-            cursor++;
+            skip_tag(&cursor);
         }
         else if(*cursor == MULTILINESYM)
         {
@@ -595,19 +570,12 @@ static int skin_parse_tag(struct skin_element* element, const char** document)
         /* Skipping over escaped characters */
         if(*cursor == TAGSYM)
         {
-            cursor++;
-            if(*cursor == '\0')
-                break;
-            cursor++;
+            skip_tag(&cursor);
         }
         else if(*cursor == COMMENTSYM)
         {
             skip_comment(&cursor);
         }
-        else if(*cursor == ARGLISTOPENSYM)
-        {
-            skip_arglist(&cursor);
-        }
         else if(*cursor == ARGLISTSEPARATESYM)
         {
             num_args++;
@@ -974,18 +942,9 @@ static int skin_parse_conditional(struct skin_element* element, const char** doc
         {
             skip_comment(&cursor);
         }
-        else if(*cursor == ENUMLISTOPENSYM)
-        {
-            if (*cursor == '\n')
-                cursor++;
-            skip_enumlist(&cursor);
-        }
         else if(*cursor == TAGSYM)
         {
-            cursor++;
-            if(*cursor == '\0' || *cursor == '\n')
-                break;
-            cursor++;
+            skip_tag(&cursor);
         }
         else if(*cursor == ENUMLISTSEPARATESYM)
         {
@@ -1139,21 +1098,7 @@ static struct skin_element* skin_parse_code_as_arg(const char** document)
         }
         else if(*cursor == TAGSYM)
         {
-            /* A ';' directly after a '%' doesn't count */
-            cursor ++;
-
-            if(*cursor == '\0')
-                break;
-
-            cursor++;
-        }
-        else if(*cursor == ARGLISTOPENSYM)
-        {
-            skip_arglist(&cursor);
-        }
-        else if(*cursor == ENUMLISTOPENSYM)
-        {
-            skip_enumlist(&cursor);
+            skip_tag(&cursor);
         }
         else
         {