Filters are now direct children of main process.

Header file now generated through m4.

7 files changed, 124 insertions, 47 deletions

diff --git a/filter.c b/filter.c
index 7a93a4e..34659b3 100644
--- a/filter.c
+++ b/filter.c
@@ -102,7 +102,8 @@ struct filter *filter_create_ext (struct filter *chain, const char *cmd,
  * @return newest filter in chain
  */
 struct filter *filter_create_int (struct filter *chain,
-				  int (*filter_func) (struct filter *), void *extra)
+				  int (*filter_func) (struct filter *),
+				  void *extra)
 {
 	struct filter *f;
 
@@ -134,8 +135,17 @@ bool filter_apply_chain (struct filter * chain)
 {
 	int     pid, pipes[2];
 
-	if (chain == NULL)
-		return true;
+    /* Tricky recursion, since we want to begin the chain
+     * at the END. Why? Because we need all the forked processes
+     * to be children of the main flex process.
+     */
+	if (chain)
+		filter_apply_chain(chain->next);
+    else
+        return true;
+
+    /* Now we are the right-most unprocessed link in the chain.
+     */
 
 	fflush (stdout);
 	fflush (stderr);
@@ -152,27 +162,27 @@ bool filter_apply_chain (struct filter * chain)
 		if (dup2 (pipes[0], 0) == -1)
 			flexfatal (_("dup2(pipes[0],0)"));
 		close (pipes[0]);
-		if ((stdin = fdopen (0, "r")) == NULL)
-			flexfatal (_("fdopen(0) failed"));
-
-        /* recursively apply rest of chain. */
-		filter_apply_chain (chain->next);
-
-        /* run this filter, either internally or by execvp */
-        if  (chain->filter_func){
-            int r = chain->filter_func(chain);
-            if (r == -1)
-                flexfatal (_("filter_func failed"));
-            else{
-                close(0);
-                close(1);
-                exit(0);
-            }
-        }
-        else{
-            execvp (chain->argv[0], (char **const) (chain->argv));
+
+		/* run as a filter, either internally or by exec */
+		if (chain->filter_func) {
+            int r;
+
+            /* setup streams again */
+            if ((stdin = fdopen (0, "r")) == NULL)
+                flexfatal (_("fdopen(0) failed"));
+            if ((stdout = fdopen (1, "w")) == NULL)
+                flexfatal (_("fdopen(1) failed"));
+
+			if((r = chain->filter_func (chain)) == -1)
+				flexfatal (_("filter_func failed"));
+            exit(0);
+		}
+		else {
+            execvp (chain->argv[0],
+                (char **const) (chain->argv));
             flexfatal (_("exec failed"));
-        }
+		}
+
 		exit (1);
 	}
 
@@ -211,17 +221,80 @@ int filter_truncate (struct filter *chain, int max_len)
 /** Splits the chain in order to write to a header file.
  *  Similar in spirit to the 'tee' program.
  *  The header file name is in extra.
+ *  @return 0 (zero) on success, and -1 on failure.
  */
-int filter_tee (struct filter *chain)
+int filter_tee_header (struct filter *chain)
 {
-    const int readsz = 512;
-    char * buf;
-    
-    buf = (char*)flex_alloc(readsz);
-    header_out = fopen (headerfilename, "w");
-    
-    execlp("cat","cat",NULL);
+	/* This function reads from stdin and writes to both the C file and the
+	 * header file at the same time.
+	 */
+
+	const int readsz = 512;
+	char   *buf;
+	int     to_cfd;
+	FILE   *to_c, *to_h;
+
+    fprintf(stderr,"filter_tee()\n");fflush(stderr);
+
+	if (!chain->extra) {
+		/* No header file was specified, so we become a transparent
+		 * filter.
+		 */
+        fprintf(stderr,"\texeclp(cat)\n");fflush(stderr);
+		execlp ("cat", "cat", NULL);
+		flexfatal (_("exec failed"));
+	}
+
+	/* Store a copy of the stdout pipe, which is already piped to C file
+	 * through the running chain. Then create a new pipe to the H file as
+	 * stdout, and fork the rest of the chain again.
+	 */
+
+	if ((to_cfd = dup (1)) == -1)
+		flexfatal (_("dup(1) failed"));
+
+	if (freopen ((char *) chain->extra, "w", stdout) == NULL)
+		flexfatal (_("freopen(headerfilename) failed"));
+
+	filter_apply_chain (chain->next);
+
+	to_c = fdopen (to_cfd, "w");
+	to_h = stdout;
+
+	/* Now to_c is a pipe to the C branch, and to_h is a pipe to the H branch.
+	 */
+
+    fprintf(stderr,"\tpid(%d): to_c=%d, to_h=%d\n",
+            getpid(),fileno(to_c),fileno(to_h)); fflush(stderr);
+
+	fputs ("m4_changequote`'m4_dnl\n", to_h);
+	fputs ("m4_changequote([[,]])[[]]m4_dnl\n", to_h);
+	fputs ("m4_define( [[M4_YY_IN_HEADER]],[[]])m4_dnl\n", to_h);
+	fprintf (to_h, "#ifndef %sHEADER_H\n", prefix);
+	fprintf (to_h, "#define %sHEADER_H 1\n", prefix);
+	fprintf (to_h, "#define %sIN_HEADER 1\n\n", prefix);
+
+	buf = (char *) flex_alloc (readsz);
+	while (fgets (buf, readsz, stdin)) {
+		fputs (buf, to_c);
+		fputs (buf, to_h);
+	}
+
+	fprintf (to_h, "\n");
+	fprintf (to_h, "#undef %sIN_HEADER\n", prefix);
+	fprintf (to_h, "#endif /* %sHEADER_H */\n", prefix);
+	fputs ("m4_undefine( [[M4_YY_IN_HEADER]])m4_dnl\n", to_h);
+
+	fflush (to_c);
+	fclose (to_c);
+
+	fflush (to_h);
+    fclose (to_h);
+
+    while(wait(0) > 0)
+        ;
 
+	exit(0);
     return 0;
 }
 
diff --git a/flex.skl b/flex.skl
index 82c7fe1..8c9baf9 100644
--- a/flex.skl
+++ b/flex.skl
@@ -1486,7 +1486,8 @@ m4_ifdef( [[M4_YY_USES_REJECT]],
 
 
 %if-c-only
-#ifndef YY_NO_UNPUT
+m4_ifdef( [[M4_YY_NO_UNPUT]],,
+[[
     static void yyunput YYFARGS2( int,c, register char *,yy_bp)
 %endif
 %if-c++-only
@@ -1534,7 +1535,7 @@ m4_ifdef( [[M4_YY_USE_LINENO]],
 	YY_G(yy_c_buf_p) = yy_cp;
 	}
 %if-c-only
-#endif	/* ifndef YY_NO_UNPUT */
+]])
 %endif
 
 %if-c-only
@@ -2397,7 +2398,6 @@ int yylex_init( ptr_yy_globals )
 /* yylex_destroy is for both reentrant and non-reentrant scanners. */
 int yylex_destroy  YYFARGS0(void)
 {
-	int i;
     M4_YY_DECL_GUTS_VAR();
 
     /* Pop the buffer stack, destroying each element. */
diff --git a/flexdef.h b/flexdef.h
index f7aa8d4..585ea49 100644
--- a/flexdef.h
+++ b/flexdef.h
@@ -1102,8 +1102,8 @@ extern struct Buf yydmap_buf;
 extern struct Buf m4defs_buf;
 
 /* For blocking out code from the header file. */
-#define OUT_BEGIN_CODE() out_str("#ifndef %sIN_HEADER /* YY-DISCARD-FROM-HEADER */\n",prefix)
-#define OUT_END_CODE() out_str("#endif /* !%sIN_HEADER YY-END-DISCARD-FROM-HEADER */\n",prefix);
+#define OUT_BEGIN_CODE() outn("m4_ifdef( [[M4_YY_IN_HEADER]],,[[")
+#define OUT_END_CODE()   outn("]])")
 
 /* For setjmp/longjmp (instead of calling exit(2)). Linkage in main.c */
 extern jmp_buf flex_main_jmp_buf;
@@ -1161,5 +1161,6 @@ struct filter *filter_create_int PROTO((struct filter *chain,
                   void *extra));
 extern bool filter_apply_chain PROTO((struct filter * chain));
 extern int filter_truncate (struct filter * chain, int max_len);
+extern int filter_tee_header PROTO((struct filter *chain));
 
 #endif /* not defined FLEXDEF_H */
diff --git a/gen.c b/gen.c
index 7c7dfa0..73fa5d3 100644
--- a/gen.c
+++ b/gen.c
@@ -762,19 +762,19 @@ void gen_next_match ()
 	 * gen_NUL_trans().
 	 */
 	char   *char_map = useecs ?
-		"yy_ec[YY_SC_TO_UI(*yy_cp)]" : "YY_SC_TO_UI(*yy_cp)";
+		"yy_ec[YY_SC_TO_UI(*yy_cp)] " : "YY_SC_TO_UI(*yy_cp)";
 
 	char   *char_map_2 = useecs ?
-		"yy_ec[YY_SC_TO_UI(*++yy_cp)]" : "YY_SC_TO_UI(*++yy_cp)";
+		"yy_ec[YY_SC_TO_UI(*++yy_cp)] " : "YY_SC_TO_UI(*++yy_cp)";
 
 	if (fulltbl) {
 		if (gentables)
 			indent_put2s
-				("while ( (yy_current_state = yy_nxt[yy_current_state][%s]) > 0 )",
+				("while ( (yy_current_state = yy_nxt[yy_current_state][ %s ]) > 0 )",
 				 char_map);
 		else
 			indent_put2s
-				("while ( (yy_current_state = yy_nxt[yy_current_state*YY_NXT_LOLEN +  %s]) > 0 )",
+				("while ( (yy_current_state = yy_nxt[yy_current_state*YY_NXT_LOLEN +  %s ]) > 0 )",
 				 char_map);
 
 		indent_up ();
diff --git a/main.c b/main.c
index 1c2b787..4cd3f29 100644
--- a/main.c
+++ b/main.c
@@ -341,7 +341,7 @@ void check_options ()
 	}
 
     /* Setup the filter chain. */
-    output_chain = filter_create_int(NULL, filter_tee, headerfilename);
+    output_chain = filter_create_int(NULL, filter_tee_header, headerfilename);
     filter_create_ext(output_chain,"m4","-P",0);
 
     /* For debugging, only run the requested number of filters. */
@@ -599,7 +599,7 @@ void flexend (exit_status)
 	 * reason we currently can't provide a mechanism to allow the user
 	 * to inject arbitrary class members into the generated C++ scanner. - JM
 	 */
-	if (headerfilename && exit_status == 0 && outfile_created
+	if (false && headerfilename && exit_status == 0 && outfile_created
 	    && !ferror (stdout)) {
 		/* Copy the file we just wrote to a header file. */
 #define LINE_SZ 512
diff --git a/scan.l b/scan.l
index 7bcec3b..0e5b1eb 100644
--- a/scan.l
+++ b/scan.l
@@ -307,7 +307,7 @@ LEXOPT		[aceknopr]
 	stdinit		do_stdinit = option_sense;
 	stdout		use_stdout = option_sense;
     unistd      ACTION_IFDEF("YY_NO_UNISTD_H", ! option_sense);
-	unput		ACTION_IFDEF("YY_NO_UNPUT", ! option_sense);
+	unput		ACTION_M4_IFDEF("M4_YY_NO_UNPUT", ! option_sense);
 	verbose		printstats = option_sense;
 	warn		nowarn = ! option_sense;
 	yylineno	do_yylineno = option_sense; ACTION_M4_IFDEF("M4_YY_USE_LINENO", option_sense);
diff --git a/tests/test-reject/scanner.l b/tests/test-reject/scanner.l
index a561bd7..a90a1fa 100644
--- a/tests/test-reject/scanner.l
+++ b/tests/test-reject/scanner.l
@@ -50,7 +50,9 @@ m4_ifdef( [[M4_YY_REENTRANT]],
 [[
     yylex_init(&yyscanner);
 ]])
-#ifdef YY_TABLES_EXTERNAL
+
+m4_ifdef( [[M4_YY_TABLES_EXTERNAL]],
+[[
     if((fp  = fopen(argv[1],"r"))== NULL)
         yy_fatal_error("could not open tables file for reading" M4_YY_CALL_LAST_ARG);
 
@@ -58,7 +60,7 @@ m4_ifdef( [[M4_YY_REENTRANT]],
         yy_fatal_error("yytables_fload returned < 0" M4_YY_CALL_LAST_ARG);
     if(M4_YY_TABLES_VERIFY)
         exit(0);
-#endif
+]])
     
     if(argc > 2){
         if((fp  = fopen(argv[2],"r"))== NULL)
@@ -68,9 +70,10 @@ m4_ifdef( [[M4_YY_REENTRANT]],
     while(yylex(M4_YY_CALL_ONLY_ARG) != 0)
         ;
         
-#ifdef YY_TABLES_EXTERNAL
+m4_ifdef( [[M4_YY_TABLES_EXTERNAL]],
+[[
     yytables_destroy(M4_YY_CALL_ONLY_ARG);
-#endif
+]])
     yylex_destroy(M4_YY_CALL_ONLY_ARG);
 
     if(argc < 0) /* silence the compiler */