1 files changed, 25 insertions, 10 deletions
diff --git a/core/lwip/src/include/lwip/mem.h b/core/lwip/src/include/lwip/mem.h
index aeac0a81..4dbf2f64 100644
--- a/core/lwip/src/include/lwip/mem.h
+++ b/core/lwip/src/include/lwip/mem.h
@@ -58,44 +58,59 @@ typedef size_t mem_size_t;
 #ifndef mem_calloc
 #define mem_calloc calloc
 #endif
-#ifndef mem_realloc
-static inline void *mem_realloc(void *mem, mem_size_t size)
-{
-  LWIP_UNUSED_ARG(size);
-  return mem;
-}
+/* Since there is no C library allocation function to shrink memory without
+   moving it, define this to nothing. */
+#ifndef mem_trim
+#define mem_trim(mem, size) (mem)
 #endif
 #else /* MEM_LIBC_MALLOC */
 
 /* MEM_SIZE would have to be aligned, but using 64000 here instead of
  * 65535 leaves some room for alignment...
  */
-#if MEM_SIZE > 64000l
+#if MEM_SIZE > 64000L
 typedef u32_t mem_size_t;
+#define MEM_SIZE_F U32_F
 #else
 typedef u16_t mem_size_t;
+#define MEM_SIZE_F U16_F
 #endif /* MEM_SIZE > 64000 */
 
 #if MEM_USE_POOLS
 /** lwip_mem_init is not used when using pools instead of a heap */
 #define lwip_mem_init()
-/** mem_realloc is not used when using pools instead of a heap:
+/** mem_trim is not used when using pools instead of a heap:
     we can't free part of a pool element and don't want to copy the rest */
-#define mem_realloc(mem, size) (mem)
+#define mem_trim(mem, size) (mem)
 #else /* MEM_USE_POOLS */
 /* lwIP alternative malloc */
 void  lwip_mem_init(void);
-void *mem_realloc(void *mem, mem_size_t size);
+void *mem_trim(void *mem, mem_size_t size);
 #endif /* MEM_USE_POOLS */
 void *mem_malloc(mem_size_t size);
 void *mem_calloc(mem_size_t count, mem_size_t size);
 void  mem_free(void *mem);
 #endif /* MEM_LIBC_MALLOC */
 
+/** Calculate memory size for an aligned buffer - returns the next highest
+ * multiple of MEM_ALIGNMENT (e.g. LWIP_MEM_ALIGN_SIZE(3) and
+ * LWIP_MEM_ALIGN_SIZE(4) will both yield 4 for MEM_ALIGNMENT == 4).
+ */
 #ifndef LWIP_MEM_ALIGN_SIZE
 #define LWIP_MEM_ALIGN_SIZE(size) (((size) + MEM_ALIGNMENT - 1) & ~(MEM_ALIGNMENT-1))
 #endif
 
+/** Calculate safe memory size for an aligned buffer when using an unaligned
+ * type as storage. This includes a safety-margin on (MEM_ALIGNMENT - 1) at the
+ * start (e.g. if buffer is u8_t[] and actual data will be u32_t*)
+ */
+#ifndef LWIP_MEM_ALIGN_BUFFER
+#define LWIP_MEM_ALIGN_BUFFER(size) (((size) + MEM_ALIGNMENT - 1))
+#endif
+
+/** Align a memory pointer to the alignment defined by MEM_ALIGNMENT
+ * so that ADDR % MEM_ALIGNMENT == 0
+ */
 #ifndef LWIP_MEM_ALIGN
 #define LWIP_MEM_ALIGN(addr) ((void *)(((mem_ptr_t)(addr) + MEM_ALIGNMENT - 1) & ~(mem_ptr_t)(MEM_ALIGNMENT-1)))
 #endif