take care of the case where two files have different names but

are the same (at least for Unix/Linux).
recover $loaded space after initialisation.


git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@488 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

C/sysbits.c

@@ -2052,6 +2052,30 @@ p_host_type(void) {
   return(unify(out,ARG1));
 }
 
+static Int
+p_same_file(void) {
+  char *f1 = RepAtom(AtomOfTerm(Deref(ARG1)))->StrOfAE;
+  char *f2 = RepAtom(AtomOfTerm(Deref(ARG2)))->StrOfAE;
+#if HAVE_LSTAT 
+  struct stat buf1, buf2;
+  if (stat(f1, &buf1) == -1) {
+    /* file does not exist, but was opened? Return -1 */
+    return(FALSE);
+  }
+  if (stat(f2, &buf2) == -1) {
+    /* file does not exist, but was opened? Return -1 */
+    return(FALSE);
+  }
+  if (strcmp(f1,f2) == 0) {
+    printf("Here I go with %s and %s\n", f1, f2);
+  }
+  return(buf1.st_ino == buf2.st_ino &&
+	 buf1.st_dev == buf2.st_dev);
+#else
+  return(strcmp(f1,f2) == 0);
+#endif
+}
+
 /*
  * This is responsable for the initialization of all machine dependant
  * predicates
@@ -2101,6 +2125,7 @@ InitSysPreds(void)
   InitCPred ("$file_age", 2, p_file_age, SafePredFlag|SyncPredFlag);
   InitCPred ("$set_fpu_exceptions", 0, p_set_fpu_exceptions, SafePredFlag|SyncPredFlag);
   InitCPred ("$host_type", 1, p_host_type, SafePredFlag|SyncPredFlag);
+  InitCPred ("$same_file", 2, p_same_file, SafePredFlag|SyncPredFlag);
 }
 
 

pl/boot.yap

@@ -891,13 +891,15 @@ break :- '$get_value'('$break',BL), NBL is BL+1,
 '$consult'(X) :-
 	'$find_in_path'(X,Y,consult(X)),
 	'$open'(Y,'$csult',Stream,0), !,
-        '$record_loaded'(Stream),
         '$consult'(X,Stream),
 	'$close'(Stream).
 '$consult'(X) :-
 	throw(error(permission_error(input,stream,X),consult(X))).
 
 
+'$consult'(_,Stream) :-
+        '$record_loaded'(Stream),
+	fail.
 '$consult'(F,Stream) :-
 	'$access_yap_flags'(8, 2), % SICStus Prolog compatibility
 	!,
@@ -944,7 +946,7 @@ break :- '$get_value'('$break',BL), NBL is BL+1,
 '$record_loaded'(user).
 '$record_loaded'(user_input).
 '$record_loaded'(Stream) :-
-	'$loaded'(Stream), !.
+	'$loaded'(Stream,_), !.
 '$record_loaded'(Stream) :-
 	'$file_name'(Stream,F),
 	'$file_age'(F,Age),

pl/consult.yap

@@ -32,15 +32,13 @@ ensure_loaded(V) :-
 '$ensure_loaded'(X) :-
 	'$find_in_path'(X,Y,ensure_loaded(X)),
 	'$open'(Y, '$csult', Stream, 0), !,
-	( '$loaded'(Stream) ->
+	( '$loaded'(Stream,TFN) ->
-	    (  '$consulting_file_name'(Stream,TFN),
+	    (  	'$recorded'('$module','$module'(TFN,M,P),_) ->
-		'$recorded'('$module','$module'(TFN,M,P),_) ->
 		'$current_module'(T), '$import'(P,M,T)
 		;
 		true
 	    )
 	;
-	    '$record_loaded'(Stream),
 	    '$reconsult'(X,Stream)
 	    ),
 	'$close'(Stream).
@@ -86,12 +84,14 @@ reconsult(Fs) :-
 '$reconsult'(X) :-
 	'$find_in_path'(X,Y,reconsult(X)),
 	'$open'(Y,'$csult',Stream,0), !,
-	'$record_loaded'(Stream),
 	'$reconsult'(X,Stream),
 	'$close'(Stream).
 '$reconsult'(X) :-
 	throw(error(permission_error(input,stream,X),reconsult(X))).
 
+'$reconsult'(F,Stream) :-
+	'$record_loaded'(Stream),
+	fail.
 '$reconsult'(F,Stream) :-
 	'$getcwd'(OldD),
 	'$get_value'('$consulting_file',OldF),
@@ -189,7 +189,6 @@ reconsult(Fs) :-
 	),
 	( '$find_in_path'(X,Y,reconsult(X)),
 	  '$open'(Y,'$csult',Stream,0) ->
-		'$record_loaded'(Stream),
 		( '$access_yap_flags'(15, 0) -> true ; '$skip_unix_comments'(Stream) ),
 		'$reconsult'(X,Stream), '$close'(Stream)
 	;
@@ -234,9 +233,10 @@ prolog_load_context(term_position, Position) :-
 	stream_position(Stream, Position).
 
 
-'$loaded'(Stream) :-
+'$loaded'(Stream,F1) :-
 	'$file_name'(Stream,F),			%
-	'$recorded'('$loaded','$loaded'(F,Age),R), !,
+	'$recorded'('$loaded','$loaded'(F1,Age),R),
+	'$same_file'(F1,F), !,
         '$file_age'(F,CurrentAge),
          ((CurrentAge = Age ; Age = -1)  -> true; erase(R), fail).
 

pl/init.yap

@@ -107,6 +107,11 @@ system_mode(verbose,off) :- '$set_value'('$verbose',off).
    '$set_pred_module'(acyclic_term(_,_), terms),
    '$set_pred_module'(variable_in_term(_,_), terms).
 
+%
+% cleanup ensure loaded and recover some data-base space.
+%
+:- ( recorded('$loaded','$loaded'(_,_),R), erase(R), fail ; true ).
+
 :- '$set_value'('$user_module',user), '$protect'.
 
 :- style_check([]).

pl/modules.yap

@@ -60,11 +60,10 @@ use_module(M,I) :-
 	'$current_module'(M),
 	'$find_in_path'(File,X,use_module(File,Imports)), !,
 	'$open'(X,'$csult',Stream,0), !,
-	'$consulting_file_name'(Stream,TrueFileName),
+	( '$loaded'(Stream,TrueFileName) -> true
-	( '$loaded'(Stream) -> true
 	     ;
-	     '$record_loaded'(Stream),
 	       % the following avoids import of all public predicates
+	     '$consulting_file_name'(Stream,TrueFileName),
 	     '$recorda'('$importing','$importing'(TrueFileName),R),
 	     '$reconsult'(File,Stream)
 	 ),
@@ -91,14 +90,14 @@ use_module(Mod,F,I) :-
 '$use_module'(Module,File,Imports) :-
 	'$find_in_path'(File,X,use_module(Module,File,Imports)),
 	'$open'(X,'$csult',Stream,0), !,
-	'$consulting_file_name'(Stream,TrueFileName),
 	'$current_module'(M),
+	'$file_name'(Stream,FName),
 	(
-	  '$loaded'(Stream)
+	  '$loaded'(Stream, TrueFileName)
 	  ->
 	  true
 	;
-	  '$record_loaded'(Stream),
+	  '$consulting_file_name'(Stream,TrueFileName),
 	  % the following avoids import of all public predicates
 	  '$recorda'('$importing','$importing'(TrueFileName),R),
 	  '$reconsult'(File,Stream)