parser: fix inconsistencies in set expression rules

Set keys are currently defined as a regular expr for pure sets and
map_lhs_expr for maps. map_lhs_expr is what can actually be used for
a single member, namely a concat_expr or a multiton_expr. The reason
why pure sets use expr for the key is to allow recursive set specifications,
which doesn't make sense for maps since every element needs a mapping.

However, the rule is too wide and also allows map expressions as a key,
which obviously doesn't make sense.

Rearrange the rules so we have:

set_lhs_expr:	concat or multiton
set_rhs_expr:	concat or verdict

and special case the recursive set specifications, as they deserve.

Besides making it a lot easier to understand what is actually supported,
this will be used by the following patch to support timeouts and comments
for keys in a uniform way.

Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/src/parser_bison.y b/src/parser_bison.y
index cd4e096a85f9f399ffb4b6e51124db9ad8b745c0..c934533d7108f1f437f26cc5ea8010314cc95284 100644 (file)
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -470,8 +470,8 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 %destructor { expr_free($$); } prefix_expr range_expr wildcard_expr
 %type <expr>                   list_expr
 %destructor { expr_free($$); } list_expr
-%type <expr>                   concat_expr map_lhs_expr
-%destructor { expr_free($$); } concat_expr map_lhs_expr
+%type <expr>                   concat_expr
+%destructor { expr_free($$); } concat_expr
 
 %type <expr>                   map_expr
 %destructor { expr_free($$); } map_expr
@@ -484,6 +484,8 @@ static void location_update(struct location *loc, struct location *rhs, int n)
 
 %type <expr>                   set_expr set_list_expr set_list_member_expr
 %destructor { expr_free($$); } set_expr set_list_expr set_list_member_expr
+%type <expr>                   set_lhs_expr set_rhs_expr
+%destructor { expr_free($$); } set_lhs_expr set_rhs_expr
 
 %type <expr>                   expr initializer_expr
 %destructor { expr_free($$); } expr initializer_expr
@@ -1297,13 +1299,12 @@ verdict_map_list_expr   :       verdict_map_list_member_expr
                        |       verdict_map_list_expr   COMMA   opt_newline
                        ;
 
-verdict_map_list_member_expr:  opt_newline     map_lhs_expr    COLON   verdict_expr    opt_newline
+verdict_map_list_member_expr:  opt_newline     set_lhs_expr    COLON   verdict_expr    opt_newline
                        {
                                $$ = mapping_expr_alloc(&@$, $2, $4);
                        }
                        ;
 
-
 counter_stmt           :       counter_stmt_alloc
                        |       counter_stmt_alloc      counter_args
 
@@ -1718,10 +1719,6 @@ multiton_expr            :       prefix_expr
                        |       wildcard_expr
                        ;
 
-map_lhs_expr           :       multiton_expr
-                       |       concat_expr
-                       ;
-
 map_expr               :       concat_expr     MAP     expr
                        {
                                $$ = map_expr_alloc(&@$, $1, $3);
@@ -1729,9 +1726,9 @@ map_expr          :       concat_expr     MAP     expr
                        ;
 
 expr                   :       concat_expr
+                       |       multiton_expr
                        |       set_expr
                        |       map_expr
-                       |       multiton_expr
                        ;
 
 set_expr               :       '{'     set_list_expr           '}'
@@ -1754,20 +1751,28 @@ set_list_expr           :       set_list_member_expr
                        |       set_list_expr           COMMA   opt_newline
                        ;
 
-set_list_member_expr   :       opt_newline     expr    opt_newline
+set_list_member_expr   :       opt_newline     set_expr        opt_newline
                        {
                                $$ = $2;
                        }
-                       |       opt_newline     map_lhs_expr    COLON   concat_expr     opt_newline
+                       |       opt_newline     set_lhs_expr    opt_newline
                        {
-                               $$ = mapping_expr_alloc(&@$, $2, $4);
+                               $$ = $2;
                        }
-                       |       opt_newline     map_lhs_expr    COLON   verdict_expr    opt_newline
+                       |       opt_newline     set_lhs_expr    COLON   set_rhs_expr    opt_newline
                        {
                                $$ = mapping_expr_alloc(&@$, $2, $4);
                        }
                        ;
 
+set_lhs_expr           :       concat_expr
+                       |       multiton_expr
+                       ;
+
+set_rhs_expr           :       concat_expr
+                       |       verdict_expr
+                       ;
+
 initializer_expr       :       expr
                        |       list_expr
                        ;