For push mode, convert yyparse from a macro to a function, invoke yylex

instead of passing a yylexp argument to yypull_parse, and don't
generate yypull_parse or yyparse unless %push-pull-parser is declared.
Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2006-12/msg00163.html>.
* data/bison.m4 (b4_pull_if): New.
* data/c.m4 (b4_identification): Define YYPULL similar to YYPUSH.
* data/push.c: Improve M4 quoting a little.
(b4_generate_macro_args, b4_parenthesize): Remove.
(yyparse): If there's a b4_prefix, #define this to b4_prefix[parse]
any time a pull parser is requested.
Don't #define this as a wrapper around yypull_parse.  Instead, when
both push and pull are requested, make it a function that does that
same thing.
(yypull_parse): If there's a b4_prefix, #define this to
b4_prefix[pull_parse] when both push and pull are requested.
Don't define this as a function unless both push and pull are
requested.
Remove the yylexp argument and hard-code yylex invocation instead.
* etc/bench.pl.in (bench_grammar): Use %push-pull-parser instead of
%push-parser.
* src/getargs.c (pull_parser): New global initialized to true.
* getargs.h (pull_parser): extern it.
* src/output.c (prepare): Insert pull_flag muscle.
* src/parse-gram.y (PERCENT_PUSH_PULL_PARSER): New token.
(prologue_declaration): Set both push_parser and pull_parser = true for
%push-pull-parser.  Set push_parser = true and pull_parser = false for
%push-parser.
* src/scan-gram.l: Don't accept %push_parser as an alternative to
%push-parser since there's no backward-compatibility concern here.
Scan %push-pull-parser.
* tests/calc.at (Simple LALR(1) Calculator): Use %push-pull-parser
instead of %push-parser.
* tests/headers.at (export YYLTYPE): Make yylex static, and don't
prototype it in the module that calls yyparse.
* tests/input.at (Torturing the Scanner): Likewise.
* tests/local.at (AT_PUSH_IF): Check for %push-pull-parser as well.

src/getargs.c

@@ -59,6 +59,7 @@ bool error_verbose = false;
 
 bool nondeterministic_parser = false;
 bool glr_parser = false;
+bool pull_parser = true;
 bool pure_parser = false;
 bool push_parser = false;
 

src/getargs.h

@@ -52,13 +52,16 @@ extern bool error_verbose;
 
 extern bool glr_parser;
 
+/* PULL_PARSER is true if should generate a pull parser.  */
+
+extern bool pull_parser;
+
 /* PURE_PARSER is true if should generate a parser that is all pure
    and reentrant.  */
 
 extern bool pure_parser;
 
-/* PUSH_PARSER is true if should generate a parser that is capable of being
-   called asynchronously.  Is must be pure and reentrant.  */
+/* PUSH_PARSER is true if should generate a push parser.  */
 
 extern bool push_parser;
 

src/output.c

@@ -593,6 +593,7 @@ prepare (void)
   MUSCLE_INSERT_BOOL ("glr_flag", glr_parser);
   MUSCLE_INSERT_BOOL ("locations_flag", locations_flag);
   MUSCLE_INSERT_BOOL ("nondeterministic_flag", nondeterministic_parser);
+  MUSCLE_INSERT_BOOL ("pull_flag", pull_parser);
   MUSCLE_INSERT_BOOL ("pure_flag", pure_parser);
   MUSCLE_INSERT_BOOL ("push_flag", push_parser);
   MUSCLE_INSERT_BOOL ("synclines_flag", !no_lines_flag);

src/parse-gram.h

@@ -78,27 +78,28 @@
      PERCENT_PROVIDES = 292,
      PERCENT_PURE_PARSER = 293,
      PERCENT_PUSH_PARSER = 294,
-     PERCENT_REQUIRE = 295,
-     PERCENT_REQUIRES = 296,
-     PERCENT_SKELETON = 297,
-     PERCENT_START = 298,
-     PERCENT_TOKEN_TABLE = 299,
-     PERCENT_VERBOSE = 300,
-     PERCENT_YACC = 301,
-     BRACED_CODE = 302,
-     CHAR = 303,
-     EPILOGUE = 304,
-     EQUAL = 305,
-     ID = 306,
-     ID_COLON = 307,
-     PERCENT_PERCENT = 308,
-     PIPE = 309,
-     PROLOGUE = 310,
-     SEMICOLON = 311,
-     TYPE = 312,
-     TYPE_TAG_ANY = 313,
-     TYPE_TAG_NONE = 314,
-     PERCENT_UNION = 315
+     PERCENT_PUSH_PULL_PARSER = 295,
+     PERCENT_REQUIRE = 296,
+     PERCENT_REQUIRES = 297,
+     PERCENT_SKELETON = 298,
+     PERCENT_START = 299,
+     PERCENT_TOKEN_TABLE = 300,
+     PERCENT_VERBOSE = 301,
+     PERCENT_YACC = 302,
+     BRACED_CODE = 303,
+     CHAR = 304,
+     EPILOGUE = 305,
+     EQUAL = 306,
+     ID = 307,
+     ID_COLON = 308,
+     PERCENT_PERCENT = 309,
+     PIPE = 310,
+     PROLOGUE = 311,
+     SEMICOLON = 312,
+     TYPE = 313,
+     TYPE_TAG_ANY = 314,
+     TYPE_TAG_NONE = 315,
+     PERCENT_UNION = 316
    };
 #endif
 /* Tokens.  */
@@ -140,27 +141,28 @@
 #define PERCENT_PROVIDES 292
 #define PERCENT_PURE_PARSER 293
 #define PERCENT_PUSH_PARSER 294
-#define PERCENT_REQUIRE 295
-#define PERCENT_REQUIRES 296
-#define PERCENT_SKELETON 297
-#define PERCENT_START 298
-#define PERCENT_TOKEN_TABLE 299
-#define PERCENT_VERBOSE 300
-#define PERCENT_YACC 301
-#define BRACED_CODE 302
-#define CHAR 303
-#define EPILOGUE 304
-#define EQUAL 305
-#define ID 306
-#define ID_COLON 307
-#define PERCENT_PERCENT 308
-#define PIPE 309
-#define PROLOGUE 310
-#define SEMICOLON 311
-#define TYPE 312
-#define TYPE_TAG_ANY 313
-#define TYPE_TAG_NONE 314
-#define PERCENT_UNION 315
+#define PERCENT_PUSH_PULL_PARSER 295
+#define PERCENT_REQUIRE 296
+#define PERCENT_REQUIRES 297
+#define PERCENT_SKELETON 298
+#define PERCENT_START 299
+#define PERCENT_TOKEN_TABLE 300
+#define PERCENT_VERBOSE 301
+#define PERCENT_YACC 302
+#define BRACED_CODE 303
+#define CHAR 304
+#define EPILOGUE 305
+#define EQUAL 306
+#define ID 307
+#define ID_COLON 308
+#define PERCENT_PERCENT 309
+#define PIPE 310
+#define PROLOGUE 311
+#define SEMICOLON 312
+#define TYPE 313
+#define TYPE_TAG_ANY 314
+#define TYPE_TAG_NONE 315
+#define PERCENT_UNION 316
 
 
 
@@ -182,7 +184,7 @@ typedef union YYSTYPE
 }
 
 /* Line 1535 of yacc.c  */
-#line 186 "parse-gram.h"
+#line 188 "parse-gram.h"
 	YYSTYPE;
 # define YYSTYPE_IS_TRIVIAL 1
 # define yystype YYSTYPE /* obsolescent; will be withdrawn */

src/parse-gram.y

@@ -156,6 +156,8 @@ static int current_prec = 0;
   PERCENT_PROVIDES        "%provides"
   PERCENT_PURE_PARSER     "%pure-parser"
   PERCENT_PUSH_PARSER     "%push-parser"
+  PERCENT_PUSH_PULL_PARSER
+                          "%push-pull-parser"
   PERCENT_REQUIRE	  "%require"
   PERCENT_REQUIRES        "%requires"
   PERCENT_SKELETON        "%skeleton"
@@ -257,7 +259,8 @@ prologue_declaration:
 | "%output" "=" STRING          { spec_outfile = $3; }  /* deprecated */
 | "%parse-param" "{...}"	{ add_param ("parse_param", $2, @2); }
 | "%pure-parser"                { pure_parser = true; }
-| "%push-parser"                { push_parser = true; }
+| "%push-parser"                { push_parser = true; pull_parser = false; }
+| "%push-pull-parser"           { push_parser = true; pull_parser = true; }
 | "%require" STRING             { version_check (&@2, $2); }
 | "%skeleton" STRING            { skeleton_arg ($2, 1, &@1); }
 | "%token-table"                { token_table_flag = true; }

src/scan-gram.l

@@ -189,7 +189,8 @@ splice	 (\\[ \f\t\v]*\n)*
   "%printer"              	    return PERCENT_PRINTER;
   "%provides"                       return PERCENT_PROVIDES;
   "%pure"[-_]"parser"     	    return PERCENT_PURE_PARSER;
-  "%push"[-_]"parser"		    return PERCENT_PUSH_PARSER;
+  "%push-parser"		    return PERCENT_PUSH_PARSER;
+  "%push-pull-parser"		    return PERCENT_PUSH_PULL_PARSER;
   "%require"              	    return PERCENT_REQUIRE;
   "%requires"                       return PERCENT_REQUIRES;
   "%right"                	    return PERCENT_RIGHT;