* gc.c (scm_done_free): new.

expanded comments about scm_done_malloc.

* gc.h: added prototype for scm_done_free

NEWS

@@ -55,6 +55,13 @@ Example:
 
 * Changes to the scm_ interface
 
+** New function: scm_done_free (long size)
+
+This function is the inverse of scm_done_malloc.  Use it to report the
+amount of smob memory you free.  The previous method, which involved
+calling scm_done_malloc with negative argument, was somewhat
+unintuitive (and is still available, of course).
+
 ** New global variable scm_gc_running_p introduced.
 
 Use this variable to find out if garbage collection is being executed.  Up to

libguile/ChangeLog

@@ -1,3 +1,10 @@
+2000-07-15  Michael Livshin  <mlivshin@bigfoot.com>
+
+	* gc.c (scm_done_free): new.
+	expanded comments about scm_done_malloc.
+
+	* gc.h: added prototype for scm_done_free
+
 2000-07-13  Dirk Herrmann  <D.Herrmann@tu-bs.de>
 
 	* gc.h (scm_take_stdin):  Removed.

libguile/gc.c

@@ -1733,12 +1733,12 @@ scm_gc_sweep ()
 
 /* {Front end to malloc}
  *
- * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc
+ * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc,
+ * scm_done_free
  *
  * These functions provide services comperable to malloc, realloc, and
  * free.  They are for allocating malloced parts of scheme objects.
- * The primary purpose of the front end is to impose calls to gc.
- */
+ * The primary purpose of the front end is to impose calls to gc.  */
 
 
 /* scm_must_malloc
@@ -1864,7 +1864,13 @@ scm_must_free (void *obj)
  * reason).  When a new object of this smob is created you call
  * scm_done_malloc with the size of the object.  When your smob free
  * function is called, be sure to include this size in the return
- * value. */
+ * value.
+ *
+ * If you can't actually free the memory in the smob free function,
+ * for whatever reason (like reference counting), you still can (and
+ * should) report the amount of memory freed when you actually free it.
+ * Do it by calling scm_done_malloc with the _negated_ size.  Clever,
+ * eh?  Or even better, call scm_done_free. */
 
 void
 scm_done_malloc (long size)
@@ -1884,6 +1890,12 @@ scm_done_malloc (long size)
     }
 }
 
+void
+scm_done_free (long size)
+{
+  scm_mallocated -= size;
+}
+
 
 
 

libguile/gc.h

@@ -284,6 +284,7 @@ extern void * scm_must_realloc (void *where,
 				scm_sizet olen, scm_sizet len,
 				const char *what);
 extern void scm_done_malloc (long size);
+extern void scm_done_free (long size);
 extern void scm_must_free (void *obj);
 extern void scm_remember (SCM * ptr);
 extern SCM scm_return_first (SCM elt, ...);