2011-05-18 Till Straumann <strauman@slac.stanford.edu>

	PR1797/bsps: Applied cleaned-up version of Kate's patch.
	CONFIGURE_MALLOC_BSP_SUPPORTS_SBRK is now a 'bspopts.h'
	setting and as such configurable.

1 files changed, 21 insertions, 27 deletions

diff --git a/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c b/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c
index 5d352132bd..dc6b49c6ef 100644
--- a/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c
+++ b/c/src/lib/libbsp/powerpc/shared/startup/sbrk.c
@@ -70,8 +70,8 @@
 #include <sys/types.h>
 #include <unistd.h>
 
-static uint32_t         remaining_start=0;
-static uint32_t         remaining_size=0;
+static void *           remaining_start=(void*)-1LL;
+static uintptr_t        remaining_size=0;
 
 /* App. may provide a value by defining the BSP_sbrk_policy
  * variable.
@@ -81,16 +81,17 @@ static uint32_t         remaining_size=0;
  *    0  -> limit memory effectively to 32M.
  *
  */
-extern uint32_t         BSP_sbrk_policy __attribute__((weak));
+extern uintptr_t        BSP_sbrk_policy __attribute__((weak));
 
-#define LIMIT_32M  0x02000000
+#define LIMIT_32M  ((void*)0x02000000)
 
-uintptr_t _bsp_sbrk_init(
-  uintptr_t         heap_start,
+uintptr_t bsp_sbrk_init(
+  void              *heap_start,
   uintptr_t         *heap_size_p
 )
 {
   uintptr_t         rval=0;
+  uintptr_t         policy;
 
   remaining_start =  heap_start;
   remaining_size  = *heap_size_p;
@@ -104,29 +105,22 @@ uintptr_t _bsp_sbrk_init(
     remaining_size  = rval;
   }
 
-  if ( 0 != &BSP_sbrk_policy ) {
-    switch ( BSP_sbrk_policy ) {
-      case (uint32_t)(-1):
-	*heap_size_p    += rval;
-	remaining_start  = heap_start + *heap_size_p;
-	remaining_size   = 0;
-	/* return a nonzero sbrk_amount because the libsupport code
-	 * at some point divides by this number prior to trying an
-	 * sbrk() which will fail.
-	 */
-	rval = 1;
-	break;
+  policy = (0 == &BSP_sbrk_policy ? (uintptr_t)(-1) : BSP_sbrk_policy);
+  switch ( policy ) {
+      case (uintptr_t)(-1):
+        *heap_size_p    += rval;
+        remaining_start  = heap_start + *heap_size_p;
+        remaining_size   = 0;
+      break;
 
       case 0:
-	remaining_size = 0;
-	/* see above for why we return 1 */
-	rval = 1;
-	break;
+        remaining_size = 0;
+      break;
 
       default:
-	if ( rval > BSP_sbrk_policy )
-	    rval = BSP_sbrk_policy;
-	break;
+        if ( rval > policy )
+          rval = policy;
+      break;
     }
   }
 
@@ -143,9 +137,9 @@ void *bsp_sbrk(ptrdiff_t incr)
   void *rval=(void*)-1;
 
   /* FIXME: BEWARE if size >2G */
-  if (incr <= remaining_size) {
+  if ( remaining_start != (void*)-1LL && incr <= remaining_size) {
     remaining_size-=incr;
-    rval = (void*)remaining_start;
+    rval = remaining_start;
     remaining_start += incr;
   } else {
     errno = ENOMEM;