Fix sarena comments

include/ucore/sarena.h

@@ -10,14 +10,14 @@ extern "C" {
 /** @file
  * Static arena allocator.
  *
- *  An UCSArena allocates memory from pre-existing array
+ *  An UCSArena allocates memory from a provided buffer.
  *
- * The backing array should be suitable aligned to the types
+ * The backing buffer should be suitable aligned to the types
  * that will be allocated from it. Use .e.g
  * @code
  * _Alignas(16) char mem[1024];
  * @endcode
- * as the backing array.
+ * as the backing buffer.
  *
  * Once allocated, a piece of memory obtained from the
  * allocator cannot be free'd individually, only the entire SArena can
@@ -31,29 +31,30 @@ struct UCSArena {
 };
 
 /** Initialize a UCSArena with predefined backing array.
+ *
  * @data must be an array type
  * Use as
  * @code
  * _Alignas(16) char v[128];
- * SArana a = UC_BV_STATIC_INIT(v);
+ * UCSArena a = UC_BV_STATIC_INITIALIZER(v);
  * @endcode
  */
-#define UC_SAR_STATIC_INIT(data)\
+#define UC_SAR_STATIC_INITIALIZER(data)\
-    UC_SAR_INIT((data), sizeof(data))
+    UC_SAR_INITIALIZER((data), sizeof(data))
 
-/** Initialize a UCSArena with predefined memory
+/** Initializer for UCSArena with predefined memory
  * Use as
  * @code
  * char v[128];
- * SArana a = UC_BV_STATIC_INIT(v, sizeof v);
+ * UCSArena a = UC_BV_STATIC_INITIALIZER(v, sizeof v);
  * @endcode
  * or
  * @code
  * char *m = malloc(128);
- * SArana a = UC_BV_INIT(m, 128);
+ * UCSArena a = UC_BV_INIT(m, 128);
  * @endcode
  */
-#define UC_SAR_INIT(data, sz)\
+#define UC_SAR_INITIALIZER(data, sz)\
     {\
     (data),\
     (data),\
@@ -61,7 +62,7 @@ struct UCSArena {
     }
 
 /** Initialize a UCSArena with an array as the backing memory to allocate from.
- * The macro can be used at local scope to allocate memory automatic (stack) storage,
+ * The macro can be used at local scope to allocate memory automatic on the stack,
  * or at global scope where the backing array will have static storage duration
  *
  * Use as:
@@ -73,7 +74,7 @@ struct UCSArena {
  * }
  * @endcode
  *
- * @note, the backing store has alignment of 16. Use manual init if a different alignment
+ * @note, the backing buffer has alignment of 16. Use manual init if a different alignment
  * is needed.
  * @param var_name Variable name for the allocator
  * @param size_  byte size of the backing array
@@ -82,7 +83,7 @@ struct UCSArena {
     struct {\
         _Alignas(16) char memory[size_]; \
     } var_name ## _memory;\
-    UCSArena var_name = UC_SAR_STATIC_INIT(var_name ## _memory.memory)
+    UCSArena var_name = UC_SAR_STATIC_INITIALIZER(var_name ## _memory.memory)
 
 /** Allocate space for @type_ , returned memory is aligned to requirements
  * of @type.
@@ -91,19 +92,27 @@ struct UCSArena {
  * @code
  * UC_SAR_ALLOC_DEF(my_allocator, 1024)
  * struct foo *foo = UC_SAR_ALLOC_ALIGNED(&my_allocator, struct foo);
- * // Array types can be used too, room for null terminated string of lengh 10:
+ * // Array types can be used too:
- * char *str = UC_SAR_ALLOC_ALIGNED(&my_allocator, char[11]);
+ * struct Foo *str = UC_SAR_ALLOC_ALIGNED(&my_allocator, struct Foo[32]);
  * @endcode
  */
 #define UC_SAR_ALLOC_ALIGNED(allocator, type_) \
     uc_sar_alloc_aligned((allocator), sizeof (type_), _Alignof(type_))
 
+//Initialize an UCSArena to allocate from @mem which is @sz bytes
+static  inline void uc_sar_init(UCSArena *a, void *mem, size_t sz)
+{
+    a->start = a->curr = mem;
+    a->end = a->start + sz;
+}
+
 // Allocate @sz bytes from the UCSArena. Returns NULL if not enough space
 void *uc_sar_alloc(UCSArena *a, size_t sz);
 
 // Allocate @sz bytes from the UCSArena, returned pointer is aligned to @align
 // Returns NULL if not enough space
-void *uc_sar_alloc_aligned(UCSArena *a, size_t sz, unsigned int align);
+void *uc_sar_alloc_aligned(UCSArena *a, size_t sz, unsigned int align) [[gnu::alloc_align(2)]];
+
 
 static inline void uc_sar_reset(UCSArena *a)
 {

src/sarena.c

@@ -18,7 +18,7 @@ void *uc_sar_alloc_aligned(UCSArena *a, size_t sz, unsigned int align)
 
     uintptr_t curr = (uintptr_t)a->curr;
     uintptr_t aligned = (curr + (align - (uintptr_t)1)) & ~(align - (uintptr_t)1);
-    char *start = (char *)aligned;
+    unsigned char *start = (unsigned char *)aligned;
 
      if (start + sz > a->end) {
         return NULL;