From ee76d39f385330d10c2dd31169d98a8d8ed9a94a Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Tue, 24 Apr 2018 15:08:39 -0700
Subject: [PATCH] Remove un-thread safe shared reference count.

---
 include/refcount.h |  6 +++++-
 src/refcount.c     | 26 +++++++++++++-------------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/include/refcount.h b/include/refcount.h
index 3339c3b..c6c1ed8 100644
--- a/include/refcount.h
+++ b/include/refcount.h
@@ -34,7 +34,11 @@ struct libab_ref_s {
     /**
      * Whether this reference is a strong reference.
      */
-    int strong;
+    unsigned int strong:1;
+    /**
+     * Whether this reference is a NULL reference.
+     */
+    unsigned int null:1;
     /**
      * The reference count struct keeping track
      * of how many references are pointing to the value.
diff --git a/src/refcount.c b/src/refcount.c
index d926161..93a2963 100644
--- a/src/refcount.c
+++ b/src/refcount.c
@@ -5,6 +5,7 @@
 libab_result libab_ref_new(libab_ref* ref, void* data,
                            void (*free_func)(void* data)) {
     libab_result result = LIBAB_SUCCESS;
+    ref->null = 0;
     ref->strong = 1;
     ref->data = data;
     if ((ref->count = malloc(sizeof(*(ref->count))))) {
@@ -16,13 +17,8 @@ libab_result libab_ref_new(libab_ref* ref, void* data,
     return result;
 }
 
-static libab_ref_count null_count = {NULL, 0, 1};
-
 void libab_ref_null(libab_ref* ref) {
-    ref->strong = 0;
-    ref->data = NULL;
-    ref->count = &null_count;
-    null_count.weak++;
+    ref->null = 1;
 }
 
 void _libab_ref_changed(libab_ref* ref) {
@@ -38,7 +34,7 @@ void _libab_ref_changed(libab_ref* ref) {
 }
 
 void libab_ref_weaken(libab_ref* ref) {
-    if (ref->strong) {
+    if (!ref->null && ref->strong) {
         ref->count->strong--;
         ref->strong = 0;
         _libab_ref_changed(ref);
@@ -46,14 +42,18 @@ void libab_ref_weaken(libab_ref* ref) {
 }
 
 void libab_ref_free(libab_ref* ref) {
-    ref->count->strong -= ref->strong;
-    ref->count->weak--;
-    _libab_ref_changed(ref);
+    if(!ref->null) {
+        ref->count->strong -= ref->strong;
+        ref->count->weak--;
+        _libab_ref_changed(ref);
+    }
 }
 
 void libab_ref_copy(const libab_ref* ref, libab_ref* into) {
-    ref->count->strong++;
-    ref->count->weak++;
+    if(!ref->null) {
+        ref->count->strong++;
+        ref->count->weak++;
+    }
     memcpy(into, ref, sizeof(*ref));
 }
 
@@ -61,7 +61,7 @@ void libab_ref_data_free(void* data) { free(data); }
 
 void* libab_ref_get(const libab_ref* ref) {
     void* to_return = NULL;
-    if (ref->count->strong > 0) {
+    if (!ref->null && ref->count->strong > 0) {
         to_return = ref->data;
     }
     return to_return;