style: rename spec_defines_file as spec_header_file

The variable spec_defines_file denotes the name of the generated
header.  Its name is derived from --defines/%defines, whose name in
turn is derived from the fact that the header, in Yacc, contained the

Not only does the header now contain a lot more than just the token
definitions, but we no longer even generate macros, but an enum...

Let's modernize our vocabulary.

* src/files.h, src/files.c (spec_defines_file): Rename as...
(spec_header_file): this.

src/files.c

@@ -51,7 +51,7 @@ location spec_name_prefix_loc = EMPTY_LOCATION_INIT;
 char *spec_verbose_file = NULL;  /* for --verbose. */
 char *spec_graph_file = NULL;    /* for -g. */
 char *spec_xml_file = NULL;      /* for -x. */
-char *spec_defines_file = NULL;  /* for --defines. */
+char *spec_header_file = NULL;  /* for --defines. */
 char *parser_file_name;
 
 /* All computed output file names.  */
@@ -335,8 +335,8 @@ compute_output_file_names (void)
 
   if (defines_flag)
     {
-      if (! spec_defines_file)
-        spec_defines_file = concat2 (all_but_ext, header_extension);
+      if (! spec_header_file)
+        spec_header_file = concat2 (all_but_ext, header_extension);
     }
 
   if (graph_flag)
@@ -429,7 +429,7 @@ output_file_names_free (void)
   free (spec_verbose_file);
   free (spec_graph_file);
   free (spec_xml_file);
-  free (spec_defines_file);
+  free (spec_header_file);
   free (parser_file_name);
   free (dir_prefix);
   for (int i = 0; i < generated_files_size; i++)

src/files.h

@@ -48,7 +48,7 @@ extern char *spec_graph_file;
 extern char *spec_xml_file;
 
 /* File name specified with --defines.  */
-extern char *spec_defines_file;
+extern char *spec_header_file;
 
 /* Directory prefix of output file names.  */
 extern char *dir_prefix;

src/getargs.c

@@ -686,8 +686,8 @@ getargs (int argc, char *argv[])
         defines_flag = true;
         if (optarg)
           {
-            free (spec_defines_file);
-            spec_defines_file = xstrdup (AS_FILE_NAME (optarg));
+            free (spec_header_file);
+            spec_header_file = xstrdup (AS_FILE_NAME (optarg));
           }
         break;
 

src/output.c

@@ -679,7 +679,7 @@ prepare (void)
 #define DEFINE(Name) MUSCLE_INSERT_STRING (#Name, Name ? Name : "")
   DEFINE (dir_prefix);
   DEFINE (parser_file_name);
-  DEFINE (spec_defines_file);
+  DEFINE (spec_header_file);
   DEFINE (spec_file_prefix);
   DEFINE (spec_graph_file);
   DEFINE (spec_name_prefix);

src/parse-gram.c

@@ -2348,7 +2348,7 @@ yyreduce:
 #line 313 "src/parse-gram.y" /* yacc.c:1652  */
     {
       defines_flag = true;
-      spec_defines_file = xstrdup ((yyvsp[0].STRING));
+      spec_header_file = xstrdup ((yyvsp[0].STRING));
     }
 #line 2354 "src/parse-gram.c" /* yacc.c:1652  */
     break;

src/parse-gram.y

@@ -313,7 +313,7 @@ prologue_declaration:
 | "%defines" STRING
     {
       defines_flag = true;
-      spec_defines_file = xstrdup ($2);
+      spec_header_file = xstrdup ($2);
     }
 | "%error-verbose"                 { handle_error_verbose (&@$, $1); }
 | "%expect" INT                    { expected_sr_conflicts = $2; }