Changeset f9c3ef44 in mainline for uspace/lib/c/generic/malloc.c

Timestamp:

2012-07-28T09:01:24Z (12 years ago)

Author:

Frantisek Princ <frantisek.princ@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

8847142

Parents:

7df0c2ff (diff), b2ba418 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge with mainline

File:

• uspace/lib/c/generic/malloc.c (modified) (8 diffs)

uspace/lib/c/generic/malloc.c

@@ -110 +110 @@
 
 #define AREA_LAST_BLOCK_HEAD(area) \
-        ((uintptr_t) BLOCK_HEAD(((heap_block_foot_t *)AREA_LAST_BLOCK_FOOT(area))))
+        ((uintptr_t) BLOCK_HEAD(((heap_block_foot_t *) AREA_LAST_BLOCK_FOOT(area))))
 
 /** Get header in heap block.
@@ -349 +349 @@
                 return false;
         
-        heap_block_head_t *last_head = (heap_block_head_t *) AREA_LAST_BLOCK_HEAD(area);
+        heap_block_head_t *last_head =
+            (heap_block_head_t *) AREA_LAST_BLOCK_HEAD(area);
         
         if (last_head->free) {
@@ -651 +652 @@
 
 /** Try to enlarge any of the heap areas.
- *  If successful, allocate block of the given size in the area.
- *
+ *
+ * If successful, allocate block of the given size in the area.
  * Should be called only inside the critical section.
  *
- * @param size Gross size of item to allocate (bytes).
+ * @param size  Gross size of item to allocate (bytes).
  * @param align Memory address alignment.
+ *
+ * @return Allocated block.
+ * @return NULL on failure.
  *
  */
@@ -663 +667 @@
         if (size == 0)
                 return NULL;
-                
+        
         /* First try to enlarge some existing area */
         for (heap_area_t *area = first_heap_area; area != NULL;
             area = area->next) {
-            
+                
                 if (area_grow(area, size + align)) {
-                        heap_block_head_t *first = (heap_block_head_t *) AREA_LAST_BLOCK_HEAD(area);
-                        
-                        void *addr = malloc_area(area, first, NULL, size, align);
+                        heap_block_head_t *first =
+                            (heap_block_head_t *) AREA_LAST_BLOCK_HEAD(area);
+                        
+                        void *addr =
+                            malloc_area(area, first, NULL, size, align);
                         malloc_assert(addr != NULL);
                         return addr;
@@ -679 +685 @@
         /* Eventually try to create a new area */
         if (area_create(AREA_OVERHEAD(size + align))) {
-                heap_block_head_t *first = (heap_block_head_t *) AREA_FIRST_BLOCK_HEAD(last_heap_area);
-                
-                void *addr = malloc_area(last_heap_area, first, NULL, size, align);
+                heap_block_head_t *first =
+                    (heap_block_head_t *) AREA_FIRST_BLOCK_HEAD(last_heap_area);
+                
+                void *addr =
+                    malloc_area(last_heap_area, first, NULL, size, align);
                 malloc_assert(addr != NULL);
                 return addr;
@@ -707 +715 @@
         
         size_t falign = lcm(align, BASE_ALIGN);
-
+        
         /* Check for integer overflow. */
         if (falign < align)
                 return NULL;
-
-        size_t gross_size = GROSS_SIZE(size);
-        
-        heap_block_head_t *split;
+        
+        /*
+         * The size of the allocated block needs to be naturally
+         * aligned, because the footer structure also needs to reside
+         * on a naturally aligned address in order to avoid unaligned
+         * memory accesses.
+         */
+        size_t gross_size = GROSS_SIZE(ALIGN_UP(size, BASE_ALIGN));
         
         /* Try the next fit approach */
-        split = next_fit;
+        heap_block_head_t *split = next_fit;
         
         if (split != NULL) {
@@ -754 +766 @@
 void *calloc(const size_t nmemb, const size_t size)
 {
+        // FIXME: Check for overflow
+        
         void *block = malloc(nmemb * size);
         if (block == NULL)
@@ -893 +907 @@
         if (addr == NULL)
                 return;
-
+        
         futex_down(&malloc_futex);