Re: [PATCH v4 nft] Set/print standard chain prios with textual names

[Máté Eckl <ecklm94@xxxxxxxxx>]

On Wed, Aug 01, 2018 at 06:50:14PM +0200, Máté Eckl wrote:
[...]
> > > > > 
> > > > > Could you store the string plus offset instead of building this
> > > > > string that you need to parse again from the evaluation phase?
> > > > > 
> > > > > Probably you could reuse the existing priority integer field, then, if
> > > > > the label is non-NULL, then it means the priority integer becomes an
> > > > > offset.

I tried another way of doing this. I think it will be good if you don't mind
adding a new attribute to the parser's union. I have attached the diff for the
parser, I'd like to test it a bit more before sending a new version of the
patch.

I also changed the chain and flowtable priority attributes to prio_spec and this
way it is quite simple in the parser and in evaluate.c.

diff --git a/src/parser_bison.y b/src/parser_bison.y
index 98bfeba..73af3bc 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -153,6 +153,7 @@ int nft_lex(void *, void *, void *);
 	const struct datatype	*datatype;
 	struct handle_spec	handle_spec;
 	struct position_spec	position_spec;
+	struct prio_spec	prio_spec;
 	const struct exthdr_desc *exthdr_desc;
 }
 
@@ -182,6 +183,8 @@ int nft_lex(void *, void *, void *);
 %token AT			"@"
 %token VMAP			"vmap"
 
+%token PLUS			"+"
+
 %token INCLUDE			"include"
 %token DEFINE			"define"
 %token REDEFINE			"redefine"
@@ -522,6 +525,7 @@ int nft_lex(void *, void *, void *);
 %type <handle>			set_spec setid_spec set_identifier flowtable_identifier obj_spec objid_spec obj_identifier
 %destructor { handle_free(&$$); } set_spec setid_spec set_identifier obj_spec objid_spec obj_identifier
 %type <val>			family_spec family_spec_explicit chain_policy prio_spec
+%type <prio_spec>		extended_prio_spec
 
 %type <string>			dev_spec quota_unit
 %destructor { xfree($$); }	dev_spec quota_unit
@@ -1633,7 +1637,7 @@ flowtable_block_alloc	:	/* empty */
 flowtable_block		:	/* empty */	{ $$ = $<flowtable>-1; }
 			|	flowtable_block	common_block
 			|	flowtable_block	stmt_separator
-			|	flowtable_block	HOOK		STRING	PRIORITY        prio_spec	stmt_separator
+			|	flowtable_block	HOOK		STRING	PRIORITY	extended_prio_spec	stmt_separator
 			{
 				$$->hookstr	= chain_hookname_lookup($3);
 				if ($$->hookstr == NULL) {
@@ -1766,7 +1770,7 @@ type_identifier		:	STRING	{ $$ = $1; }
 			|	CLASSID { $$ = xstrdup("classid"); }
 			;
 
-hook_spec		:	TYPE		STRING		HOOK		STRING		dev_spec	PRIORITY	prio_spec
+hook_spec		:	TYPE		STRING		HOOK		STRING		dev_spec	PRIORITY	extended_prio_spec
 			{
 				const char *chain_type = chain_type_name_lookup($2);
 
@@ -1788,9 +1792,37 @@ hook_spec		:	TYPE		STRING		HOOK		STRING		dev_spec	PRIORITY	prio_spec
 				}
 				xfree($4);
 
-				$<chain>0->dev		= $5;
-				$<chain>0->priority	= $7;
-				$<chain>0->flags	|= CHAIN_F_BASECHAIN;
+				$<chain>0->dev = $5;
+				$<chain>0->priority = $7;
+				$<chain>0->flags |= CHAIN_F_BASECHAIN;
+			}
+			;
+
+extended_prio_spec	:	prio_spec
+			{
+				struct prio_spec spec = {0};
+				spec.num = $1;
+				$$ = spec;
+			}
+			|	STRING
+			{
+				struct prio_spec spec = {0};
+				spec.str = xstrdup($1);
+				$$ = spec;
+			}
+			|	STRING PLUS NUM
+			{
+				struct prio_spec spec = {0};
+				spec.num = $3;
+				spec.str = xstrdup($1);
+				$$ = spec;
+			}
+			|	STRING DASH NUM
+			{
+				struct prio_spec spec = {0};
+				spec.num = -$3;
+				spec.str = xstrdup($1);
+				$$ = spec;
 			}
 			;