Patch for cpplib clients to free resources

[Neil Booth <neil at daikokuya dot demon dot co dot uk>]

This fixes a rather large memory leak in all cpplib clients.

This is my last patch before the slush, after which I'll concentrate
on performance enhancements (since cpplib has no known bugs :-))

Bootstrapped i586 Linux.

Neil.

	* c-parse.in (finish_parse): Get error count from cpp_destroy.
	* cp/lex.c (finish_parse): Similarly.
	* cppinit.c (cpp_cleanup): Rename cpp_destroy for clarity.
	Return the number of errors encountered.
	* cpplib.h (cpp_cleanup): Rename cpp_destroy, return int.
	* cppmain.c (main): Update to call cpp_destroy.
	* fix-header.c (read_scan_file): Update to call cpp_destroy.

Index: c-parse.in
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-parse.in,v
retrieving revision 1.78
diff -u -p -r1.78 c-parse.in
--- c-parse.in	2001/01/13 14:23:03	1.78
+++ c-parse.in	2001/01/14 17:27:26
@@ -3161,7 +3161,7 @@ void
 finish_parse ()
 {
   cpp_finish (parse_in);
-  errorcount += cpp_errors (parse_in);
+  errorcount += cpp_destroy (parse_in);
 }
 
 #define NAME(type) cpp_type2name (type)
Index: cppinit.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cppinit.c,v
retrieving revision 1.141
diff -u -p -r1.141 cppinit.c
--- cppinit.c	2001/01/13 01:00:01	1.141
+++ cppinit.c	2001/01/14 17:27:29
@@ -557,12 +557,13 @@ cpp_create_reader (lang)
   return pfile;
 }
 
-/* Free resources used by PFILE.
-   This is the cpp_reader 'finalizer' or 'destructor' (in C++ terminology).  */
-void
-cpp_cleanup (pfile)
+/* Free resources used by PFILE.  Accessing PFILE after this function
+   returns leads to undefined behaviour.  */
+int
+cpp_destroy (pfile)
      cpp_reader *pfile;
 {
+  int result;
   struct file_name_list *dir, *dirn;
   cpp_context *context, *contextn;
 
@@ -600,6 +601,11 @@ cpp_cleanup (pfile)
       contextn = context->next;
       free (context);
     }
+
+  result = pfile->errors;
+  free (pfile);
+
+  return result;
 }
 
 
Index: cpplib.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cpplib.h,v
retrieving revision 1.160
diff -u -p -r1.160 cpplib.h
--- cpplib.h	2001/01/13 14:32:59	1.160
+++ cpplib.h	2001/01/14 17:27:50
@@ -494,6 +494,10 @@ struct cpp_hashnode
 /* Call this first to get a handle to pass to other functions.  */
 extern cpp_reader *cpp_create_reader PARAMS ((enum c_lang));
 
+/* Call this to release the handle.  Any use of the handle after this
+   function returns is invalid.  Returns cpp_errors (pfile).  */
+extern int cpp_destroy PARAMS ((cpp_reader *));
+
 /* Call these to get pointers to the options and callback structures
    for a given reader.  These pointers are good until you call
    cpp_finish on that reader.  You can either edit the callbacks
@@ -529,7 +533,6 @@ extern void cpp_register_pragma_space PA
 
 extern int cpp_start_read PARAMS ((cpp_reader *, const char *));
 extern void cpp_finish PARAMS ((cpp_reader *));
-extern void cpp_cleanup PARAMS ((cpp_reader *));
 extern int cpp_avoid_paste PARAMS ((cpp_reader *, const cpp_token *,
 				    const cpp_token *));
 extern enum cpp_ttype cpp_can_paste PARAMS ((cpp_reader *, const cpp_token *,
Index: cppmain.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cppmain.c,v
retrieving revision 1.57
diff -u -p -r1.57 cppmain.c
--- cppmain.c	2001/01/14 16:44:50	1.57
+++ cppmain.c	2001/01/14 17:27:50
@@ -79,10 +79,7 @@ main (argc, argv)
   
   do_preprocessing (argc, argv);
 
-  /* Reader destructor.  */
-  cpp_cleanup (pfile);
-
-  if (cpp_errors (pfile))
+  if (cpp_destroy (pfile))
     return FATAL_EXIT_CODE;
 
   return SUCCESS_EXIT_CODE;
Index: fix-header.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/fix-header.c,v
retrieving revision 1.63
diff -u -p -r1.63 fix-header.c
--- fix-header.c	2001/01/13 01:13:35	1.63
+++ fix-header.c	2001/01/14 17:27:50
@@ -635,11 +635,11 @@ read_scan_file (in_fname, argc, argv)
   if (i < argc && ! CPP_FATAL_ERRORS (scan_in))
     cpp_fatal (scan_in, "Invalid option `%s'", argv[i]);
   cpp_post_options (scan_in);
-  if (CPP_FATAL_ERRORS (scan_in))
-    exit (FATAL_EXIT_CODE);
-
-  if (! cpp_start_read (scan_in, in_fname))
-    exit (FATAL_EXIT_CODE);
+  if (CPP_FATAL_ERRORS (scan_in) || ! cpp_start_read (scan_in, in_fname))
+    {
+      cpp_destroy (scan_in);
+      exit (FATAL_EXIT_CODE);
+    }
 
   /* We are scanning a system header, so mark it as such.  */
   cpp_make_system_header (scan_in, 1, 0);
@@ -697,6 +697,8 @@ read_scan_file (in_fname, argc, argv)
 	    }
 	}
     }
+
+  cpp_destroy (scan_in);
 
   if (required_unseen_count + partial_count + required_other
 #if ADD_MISSING_EXTERN_C
Index: cp/lex.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/lex.c,v
retrieving revision 1.234
diff -u -p -r1.234 lex.c
--- lex.c	2001/01/13 14:23:04	1.234
+++ lex.c	2001/01/14 17:27:55
@@ -755,7 +755,7 @@ void
 finish_parse ()
 {
   cpp_finish (parse_in);
-  errorcount += cpp_errors (parse_in);
+  errorcount += cpp_destroy (parse_in);
 }
 
 inline void