FYI: obstack-less header file

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        The header can also be produced directly, without any obstack!
        Yahoo!

        * src/files.c, src/files.h (defines_obstack): Remove.
        (compute_header_macro): Global.
        (defines_obstack_save): Remove.
        * src/reader.c (parse_union_decl): No longer output to
        defines_obstack: its content can be found in the `stype' muscle
        anyway.
        (output_token_translations): Merge into...
        (symbols_output): this.
        Rename as...
        (symbols_save): this.
        (reader): Adjust.
        * src/output.c (header_output): New.
        (output): Call it.

Index: src/files.c
===================================================================
RCS file: /cvsroot/bison/bison/src/files.c,v
retrieving revision 1.57
diff -u -u -r1.57 files.c
--- src/files.c 15 Dec 2001 14:35:57 -0000 1.57
+++ src/files.c 15 Dec 2001 16:05:46 -0000
@@ -30,7 +30,6 @@
 
 struct obstack action_obstack;
 struct obstack attrs_obstack;
-struct obstack defines_obstack;
 struct obstack guard_obstack;
 struct obstack output_obstack;
 
@@ -94,7 +93,7 @@
 | alphanumerical + underscore).                                    |
 `-----------------------------------------------------------------*/
 
-static char *
+char *
 compute_header_macro (void)
 {
   const char *prefix = "BISON_";
@@ -178,26 +177,6 @@
   xfclose (out);
 }
 
-/*---------------------------------------------------------------------.
-| Output double inclusion protection macros and saves defines_obstack  |
-`---------------------------------------------------------------------*/
-
-static void
-defines_obstack_save (const char *filename)
-{
-  FILE *out = xfopen (filename, "w");
-  size_t size = obstack_object_size (&defines_obstack);
-  char *macro_name = compute_header_macro ();
-
-  fprintf (out, "#ifndef %s\n", macro_name);
-  fprintf (out, "# define %s\n\n", macro_name);
-  fwrite (obstack_finish (&defines_obstack), 1, size, out);
-  fprintf (out, "\n#endif /* not %s */\n", macro_name);
-
-  free (macro_name);
-  xfclose (out);
-}
-
 /*------------------------------------------------------------------.
 | Return the path to the skeleton which locaction might be given in |
 | ENVVAR, otherwise return SKELETON_NAME.                           |
@@ -471,7 +450,6 @@
   /* Initialize the obstacks. */
   obstack_init (&action_obstack);
   obstack_init (&attrs_obstack);
-  obstack_init (&defines_obstack);
   obstack_init (&guard_obstack);
   obstack_init (&output_obstack);
 }
@@ -495,11 +473,6 @@
 void
 output_files (void)
 {
-  /* Output the header file if wanted. */
-  if (defines_flag)
-    defines_obstack_save (spec_defines_file);
-  obstack_free (&defines_obstack, NULL);
-
 #if 0
   /* Seems to be invalid now --akim. */
 
Index: src/files.h
===================================================================
RCS file: /cvsroot/bison/bison/src/files.h,v
retrieving revision 1.21
diff -u -u -r1.21 files.h
--- src/files.h 15 Dec 2001 14:35:57 -0000 1.21
+++ src/files.h 15 Dec 2001 16:05:46 -0000
@@ -49,9 +49,6 @@
 /* Output all the action code; precise form depends on which parser. */
 extern struct obstack action_obstack;
 
-/* optionally output #define's for token numbers. */
-extern struct obstack defines_obstack;
-
 /* If semantic parser, output a .h file that defines YYSTYPE... */
 extern struct obstack attrs_obstack;
 
@@ -72,6 +69,9 @@
 
 FILE *xfopen PARAMS ((const char *name, const char *mode));
 int xfclose PARAMS ((FILE *ptr));
+
+/* Compute the double inclusion guard's name. */
+char * compute_header_macro PARAMS ((void));
 
 const char *skeleton_find PARAMS ((const char *envvar,
                                   const char *skeleton_name));
Index: src/output.c
===================================================================
RCS file: /cvsroot/bison/bison/src/output.c,v
retrieving revision 1.90
diff -u -u -r1.90 output.c
--- src/output.c 15 Dec 2001 14:35:57 -0000 1.90
+++ src/output.c 15 Dec 2001 16:05:46 -0000
@@ -91,7 +91,6 @@
 */
 
 #include "system.h"
-#include "obstack.h"
 #include "quotearg.h"
 #include "getargs.h"
 #include "files.h"
@@ -1044,6 +1043,48 @@
   MUSCLE_INSERT_INT ("locations-flag", locations_flag);
 }
 
+
+/*-------------------------.
+| Output the header file.  |
+`-------------------------*/
+
+static void
+header_output (void)
+{
+  FILE *out = xfopen (spec_defines_file, "w");
+  char *macro_name = compute_header_macro ();
+
+  fprintf (out, "#ifndef %s\n", macro_name);
+  fprintf (out, "# define %s\n\n", macro_name);
+
+  fputs (muscle_find ("tokendef"), out);
+  fprintf (out, "\
+#ifndef YYSTYPE\n\
+typedef %s
+yystype;\n\
+# define YYSTYPE yystype\n\
+#endif\n",
+                   muscle_find ("stype"));
+
+  if (!pure_parser)
+    fprintf (out, "\nextern YYSTYPE %slval;\n",
+            spec_name_prefix);
+  if (semantic_parser)
+    {
+      int i;
+
+      for (i = ntokens; i < nsyms; i++)
+       /* don't make these for dummy nonterminals made by gensym.  */
+       if (*tags[i] != '@')
+         fprintf (out, "# define\tNT%s\t%d\n", tags[i], i);
+    }
+
+  fprintf (out, "\n#endif /* not %s */\n", macro_name);
+  free (macro_name);
+  xfclose (out);
+}
+
+
 /*----------------------------------------------------------.
 | Output the parsing tables and the parser code to ftable.  |
 `----------------------------------------------------------*/
@@ -1068,7 +1109,11 @@
   obstack_1grow (&attrs_obstack, 0);
   muscle_insert ("prologue", obstack_finish (&attrs_obstack));
 
+  /* Output the parser. */
   output_master_parser ();
+  /* Output the header if needed. */
+  if (defines_flag)
+    header_output ();
 
   free (rule_table + 1);
   obstack_free (&muscle_obstack, 0);
Index: src/reader.c
===================================================================
RCS file: /cvsroot/bison/bison/src/reader.c,v
retrieving revision 1.121
diff -u -u -r1.121 reader.c
--- src/reader.c 15 Dec 2001 15:25:15 -0000 1.121
+++ src/reader.c 15 Dec 2001 16:05:46 -0000
@@ -21,7 +21,6 @@
 
 
 #include "system.h"
-#include "obstack.h"
 #include "quotearg.h"
 #include "quote.h"
 #include "getargs.h"
@@ -777,15 +776,6 @@
     ungetc (c, finput);
   obstack_1grow (&union_obstack, 0);
   muscle_insert ("stype", obstack_finish (&union_obstack));
-
-  if (defines_flag)
-    obstack_fgrow1 (&defines_obstack, "\
-#ifndef YYSTYPE\n\
-typedef %s
-yystype;\n\
-# define YYSTYPE yystype\n\
-#endif\n",
-                   muscle_find ("stype"));
 }
 
 
@@ -1567,55 +1557,6 @@
 }
 
 
-/*--------------------------------------------------------------.
-| For named tokens, but not literal ones, define the name.  The |
-| value is the user token number.                               |
-`--------------------------------------------------------------*/
-
-static void
-output_token_defines (struct obstack *oout)
-{
-  bucket *bp;
-  char *cp, *symbol;
-  char c;
-
-  for (bp = firstsymbol; bp; bp = bp->next)
-    {
-      symbol = bp->tag;                /* get symbol */
-
-      if (bp->value >= ntokens)
-       continue;
-      if (bp->user_token_number == SALIAS)
-       continue;
-      if ('\'' == *symbol)
-       continue;               /* skip literal character */
-      if (bp == errtoken)
-       continue;               /* skip error token */
-      if ('\"' == *symbol)
-       {
-         /* use literal string only if given a symbol with an alias */
-         if (bp->alias)
-           symbol = bp->alias->tag;
-         else
-           continue;
-       }
-
-      /* Don't #define nonliteral tokens whose names contain periods.  */
-      cp = symbol;
-      while ((c = *cp++) && c != '.');
-      if (c != '\0')
-       continue;
-
-      obstack_fgrow2 (oout, "# define\t%s\t%d\n",
-                     symbol, bp->user_token_number);
-      if (semantic_parser)
-       /* FIXME: This is certainly dead wrong, and should be just as
-          above. --akim.  */
-       obstack_fgrow2 (oout, "# define\tT%s\t%d\n", symbol, bp->value);
-    }
-}
-
-
 /*------------------------------------------------------------------.
 | Set TOKEN_TRANSLATIONS.  Check that no two symbols share the same |
 | number.                                                           |
@@ -1757,48 +1698,57 @@
 }
 
 
-/*-----------------------------------.
-| Output definition of token names.  |
-`-----------------------------------*/
+/*---------------------------------------------------------------.
+| Save the definition of token names in the `TOKENDEFS' muscle.  |
+`---------------------------------------------------------------*/
 
 static void
-symbols_output (void)
+symbols_save (void)
 {
-  {
-    struct obstack tokendefs;
-    obstack_init (&tokendefs);
-    output_token_defines (&tokendefs);
-    obstack_1grow (&tokendefs, 0);
-    muscle_insert ("tokendef", xstrdup (obstack_finish (&tokendefs)));
-    obstack_free (&tokendefs, NULL);
-  }
-
-  if (defines_flag)
-    {
-      output_token_defines (&defines_obstack);
-
-      if (!pure_parser)
-       obstack_fgrow1 (&defines_obstack, "\nextern YYSTYPE %slval;\n",
-                       spec_name_prefix);
-      if (semantic_parser)
-       {
-         int i;
+  struct obstack tokendefs;
+  bucket *bp;
+  char *cp, *symbol;
+  char c;
+  obstack_init (&tokendefs);
 
-         for (i = ntokens; i < nsyms; i++)
-           {
-             /* don't make these for dummy nonterminals made by gensym.  */
-             if (*tags[i] != '@')
-               obstack_fgrow2 (&defines_obstack,
-                               "# define\tNT%s\t%d\n", tags[i], i);
-           }
-#if 0
-         /* `fdefines' is now a temporary file, so we need to copy its
-            contents in `done', so we can't close it here.  */
-         fclose (fdefines);
-         fdefines = NULL;
-#endif
+  for (bp = firstsymbol; bp; bp = bp->next)
+    {
+      symbol = bp->tag;                /* get symbol */
+
+      if (bp->value >= ntokens)
+       continue;
+      if (bp->user_token_number == SALIAS)
+       continue;
+      if ('\'' == *symbol)
+       continue;               /* skip literal character */
+      if (bp == errtoken)
+       continue;               /* skip error token */
+      if ('\"' == *symbol)
+       {
+         /* use literal string only if given a symbol with an alias */
+         if (bp->alias)
+           symbol = bp->alias->tag;
+         else
+           continue;
        }
+
+      /* Don't #define nonliteral tokens whose names contain periods.  */
+      cp = symbol;
+      while ((c = *cp++) && c != '.');
+      if (c != '\0')
+       continue;
+
+      obstack_fgrow2 (&tokendefs, "# define\t%s\t%d\n",
+                     symbol, bp->user_token_number);
+      if (semantic_parser)
+       /* FIXME: This is probably wrong, and should be just as
+          above. --akim.  */
+       obstack_fgrow2 (&tokendefs, "# define\tT%s\t%d\n", symbol, bp->value);
     }
+
+  obstack_1grow (&tokendefs, 0);
+  muscle_insert ("tokendef", xstrdup (obstack_finish (&tokendefs)));
+  obstack_free (&tokendefs, NULL);
 }
 
 
@@ -1925,15 +1875,12 @@
   /* Some C code is given at the end of the grammar file. */
   read_additionnal_code ();
 
-  /* Now we know whether we need the line-number stack.  If we do,
-     write its type into the .tab.h file.
-     This is no longer need with header skeleton.  */
-
   /* Assign the symbols their symbol numbers.  Write #defines for the
      token symbols into FDEFINES if requested.  */
   packsymbols ();
+  /* Save them. */
+  symbols_save ();
+
   /* Convert the grammar into the format described in gram.h.  */
   packgram ();
-  /* Output the headers. */
-  symbols_output ();
 }