Added work on making namespaces threadsafe.

src/c/memory/pso.c

@@ -0,0 +1,47 @@
+/**
+ *  memory/pso.c
+ *
+ *  Paged space objects.
+ *
+ *  Broadly, it should be save to cast any paged space object to a pso2, since
+ *  that is the smallest actually used size class. This should work to extract 
+ *  the tag and size class fields from the header, for example. I'm not 
+ *  confident enough of my understanding of C to know whether it is similarly 
+ *  safe to cast something passed to you as a pso2 up to something larger, even
+ *  if you know from the size class field that it actually is something larger.
+ *
+ *  (c) 2026 Simon Brooke <simon@journeyman.cc>
+ *  Licensed under GPL version 2.0, or, at your option, any later version.
+ */
+
+struct cons_pointer allocate( char* tag, uint8_t size_class) {
+    struct cons_pointer result = nil;
+
+    if (size_class <= MAX_SIZE_CLASS) {
+        if ( not( freelists[size_class] ) ) {
+            result = freelists[size_class];
+            struct pso2* object = pointer_to_object( result);
+            freelists[size_class] = object->payload.free.next;
+
+            strncpy( (char *)(object->header.tag.mnemonic), tag, TAGLENGTH);
+
+            /* the object ought already to have the right size class in its tag
+             * because it was popped off the freelist for that size class. */
+            if ( object->header.tag.size_class != size_class) {
+                // TODO: return an exception instead? Or warn, set it, and continue?
+            }
+            /* the objext ought to have a reference count ot zero, because it's 
+             * on the freelist, but again we should sanity check. */
+            if ( object->header.count != 0) {
+                // TODO: return an exception instead? Or warn, set it, and continue?
+            }
+
+        }
+    } // TODO: else throw exception
+
+    return result;
+}
+
+struct cons_pointer get_tag_value( struct cons_pointer pointer) {
+    result = 
+}