tuez-moi

malloc/src/helpers/helpers.c

@@ -45,7 +45,7 @@ void *find_free_block(struct bucket *buck)
         for (unsigned j = 0; j < 8; j <<= 1)
         {
             if (map_byte & bit) // Test if free
-                return buck->page + (buck->block_size * (i * 8 + j));
+                return get_data_begin(buck) + (buck->block_size * (i * 8 + j));
 
             bit <<= 1;
         }
@@ -67,14 +67,15 @@ struct bucket *create_bucket(size_t min_alloc_size)
 
     // Init bucket
     struct bucket *header = page;
-    header->page = page + sizeof(struct bucket);
     header->block_size = alloc_size;
     memset(header->free_list, 0, FREE_LIST_SIZE);
 
     return header;
 }
 
-struct bucket *get_free_bucket(struct bucket *head, size_t size)
+// Gets a bucket with at least a block_size of size
+// Returns NULL if nothing was found
+struct bucket *get_bucket(struct bucket *head, size_t size)
 {
     while (head != NULL)
     {
@@ -84,3 +85,32 @@ struct bucket *get_free_bucket(struct bucket *head, size_t size)
 
     return NULL;
 }
+
+void *get_data_begin(struct bucket *biquette)
+{
+    // TODO alignment
+    return biquette + sizeof(struct bucket);
+}
+
+void *get_page_begin(void *ptr)
+{
+    size_t quelenfer = ((size_t)ptr) & ~(PAGE_SIZE - 1);
+    char *pointeur_alacon = NULL;
+    return pointeur_alacon + quelenfer;
+}
+
+void bucket_append(struct bucket **head, struct bucket *elt)
+{
+    struct bucket *list_elt = *head;
+    if (list_elt == NULL)
+    {
+        *head = elt;
+        return;
+    }
+
+    while (list_elt->next != NULL)
+    {
+        list_elt = list_elt->next;
+    }
+    list_elt->next = elt;
+}

malloc/src/helpers/helpers.h

@@ -15,16 +15,17 @@ struct bucket
     unsigned block_size;
     unsigned char free_list[FREE_LIST_SIZE]; // 4096 / MIN_BLOCK_SIZE /
                                              // sizeof(unsigned char)    
-    char *page;
-    
     struct bucket *next;
 
     size_t checksum;
 };
 
-size_t get_next_2power(size_t n);
+size_t s2p(size_t n);
 void *find_free_block(struct bucket *buck);
 struct bucket *create_bucket(size_t min_alloc_size);
-struct bucket *get_free_bucket(struct bucket *head, size_t size);
+struct bucket *get_bucket(struct bucket *head, size_t size);
+void *get_data_begin(struct bucket *biquette);
+void *get_page_begin(void *ptr);
+void bucket_append(struct bucket **head, struct bucket *elt);
 
 #endif // ! HELPERS_H

malloc/src/malloc.c

@@ -9,16 +9,32 @@ __attribute__((visibility("default"))) void *malloc(size_t size)
     if (size == 0)
         return NULL;
 
-    struct bucket *buck = get_free_bucket(head, size);
-    if (buck == NULL)
+    // Find adequate bucket
+    struct bucket *buck = get_bucket(head, size);
+    while (buck != NULL)
     {
-        buck = create_bucket(size);
-        return ...;
+        // Find adequate block
+        void *block = find_free_block(buck);
+        if (block != NULL)
+            return block;
+        else
+        {
+            // No free space -> loop
+            buck = get_bucket(buck->next, size);
+            continue;
         }
     }
 
+    buck = create_bucket(size);
+    bucket_append(&head, buck);
+    return get_data_begin(buck);
+}
+
 __attribute__((visibility("default"))) void free(void *ptr)
-{}
+{
+    if (ptr == NULL)
+        return;
+}
 
 __attribute__((visibility("default"))) void *realloc(void *ptr, size_t size)
 {