1 files changed, 11 insertions, 5 deletions

diff --git a/04_exercise/slotmap.c b/04_exercise/slotmap.c
index 57c4ef5..3c5a240 100644
--- a/04_exercise/slotmap.c
+++ b/04_exercise/slotmap.c
@@ -8,35 +8,41 @@ smHeader smInit(smEntry * slab, size_t size) {
     for (int i = 0; i < size; ++i) {
         slab[i].value = (intptr_t)NULL;
     }
-    return (smHeader){.slab = slab, .size=size};
+    return (smHeader){.slab = slab, .size=size, .count = 0};
 }
-int smInsert(smHeader const * header, void * value) {
+int smInsert(smHeader * header, void * value) {
     for (size_t i = 0; i< header->size; ++i ) {
         intptr_t ptr = atomic_load(&header->slab[i].value);
         if((void *)ptr == NULL) {
             intptr_t expected = (intptr_t) NULL;
             if(atomic_compare_exchange_strong(&header->slab[i].value, &expected, (intptr_t) value)){
+                atomic_fetch_add(&header->count, 1);
                 return 0;
             }
         }
     }
     return -1;
 }
-void smDelete(smEntry * node) {
+void smDelete(smHeader * header, smEntry * node) {
     intptr_t oldval = atomic_exchange(&node->value, (intptr_t)(NULL));
     if((void *) oldval == NULL) {
         fprintf(stderr, "A Node has been double deleted");
     }
+    atomic_fetch_sub(&header->count, 1);
 }
-void smDeleteValue(smHeader const * header, void * value){
+void smDeleteValue(smHeader * header, void * value){
     for (size_t i = 0; i< header->size; ++i ) {
         intptr_t ptr = atomic_load(&header->slab[i].value);
         if((void *)ptr == value) {
-            smDelete(&header->slab[i]);
+            smDelete(header, &header->slab[i]);
         }
     }
 }
 smEntry *smFindEntry(smHeader const * header, SearchFunction func){
+    int count = atomic_load(&header->count);
+    if (count == 0) {
+        return NULL;
+    }
     for (size_t i = 0; i< header->size; ++i ) {
         void * value = (void *) atomic_load(&header->slab[i].value);