Allow a user specified parameter to 'yyparse()', in a manner similar to

that used by bison.  The names are consistent with the bison implementation
but this one also allows the type of the parameter to be specified.

For a desired prototype of:

	int yyparse __P((struct yyresult *));

and compile like this:

	yacc -dv grammar.y
	cc -c -DYYPARSE_PARAM_TYPE="struct yyresult *" \
	      -DYYPARSE_PARAM="parm" y.tab.c

and use like this:

	${
	#include "usrtypes.h"
	#include "usrproto.h"
	}$

	%token NUMBER

	%%

	goal : NUMBER
		{
		parm->value = yylval;
		} ;

If YYPARSE_PARAM_TYPE isn't specified then "void *" is the default type.
If YYPARSE_PARAM is not specified then the generated code behaves exactly
as traditional byacc.

PR:		13562
Submitted by:	W Gerald Hicks <wghicks@bellsouth.net>

1 files changed, 11 insertions, 8 deletions

diff --git a/usr.bin/yacc/skeleton.c b/usr.bin/yacc/skeleton.c
index f3d6dd0..90235cb 100644
--- a/usr.bin/yacc/skeleton.c
+++ b/usr.bin/yacc/skeleton.c
@@ -67,10 +67,6 @@ char *banner[] =
     "#define yyclearin (yychar=(YYEMPTY))",
     "#define yyerrok (yyerrflag=0)",
     "#define YYRECOVERING() (yyerrflag!=0)",
-#if 0
-    "extern int yylex();",
-    "extern int yyparse();",
-#endif
     "static int yygrowstack();",
     0
 };
@@ -163,12 +159,19 @@ char *body[] =
     "#define YYACCEPT goto yyaccept",
     "#define YYERROR goto yyerrlab",
     "",
-    "int",
-    "#if defined(__cplusplus) || __STDC__",
-    "yyparse(void)",
+    "#ifndef YYPARSE_PARAM",
+    "#define YYPARSE_PARAM",
+    "#define YYPARSE_PARAM_DECL",
     "#else",
-    "yyparse()",
+    "#ifndef YYPARSE_PARAM_TYPE",
+    "#define YYPARSE_PARAM_TYPE void *",
+    "#endif",
+    "#define YYPARSE_PARAM_DECL YYPARSE_PARAM_TYPE YYPARSE_PARAM;",
     "#endif",
+    "",
+    "int",
+    "yyparse (YYPARSE_PARAM)",
+    "    YYPARSE_PARAM_DECL",
     "{",
     "    register int yym, yyn, yystate;",
     "#if YYDEBUG",