From 81dea364a5b372ad1625181eff710c095420735c Mon Sep 17 00:00:00 2001
From: Ian Martin <ian@locicontrols.com>
Date: Mon, 27 Oct 2014 20:00:52 -0400
Subject: [PATCH] cpu/cc2538: sbrk() checks if the requested memory is really
available.
---
cpu/cc2538/Makefile.include | 4 ++++
cpu/cc2538/syscalls.c | 31 +++++++++++++++++++++----------
2 files changed, 25 insertions(+), 10 deletions(-)
diff --git a/cpu/cc2538/Makefile.include b/cpu/cc2538/Makefile.include
index e851b58687..c282717bd4 100644
--- a/cpu/cc2538/Makefile.include
+++ b/cpu/cc2538/Makefile.include
@@ -10,6 +10,10 @@ export CORTEX_COMMON = $(RIOTCPU)/cortex-m3_common/
# Define the linker script to use for this CPU:
export LINKERSCRIPT = $(RIOTCPU)/$(CPU)/$(CPU_MODEL)_linkerscript.ld
+# Export the CPU model:
+MODEL = $(shell echo $(CPU_MODEL) | tr 'a-z' 'A-Z')
+export CFLAGS += -DCPU_MODEL_$(MODEL)
+
# Include CPU specific includes:
export INCLUDES += -I$(RIOTCPU)/$(CPU)/include
diff --git a/cpu/cc2538/syscalls.c b/cpu/cc2538/syscalls.c
index d1bb148835..84721323a9 100644
--- a/cpu/cc2538/syscalls.c
+++ b/cpu/cc2538/syscalls.c
@@ -39,6 +39,13 @@
#ifdef MODULE_UART0
#include "board_uart0.h"
#endif
+
+#ifdef CPU_MODEL_CC2538NF11
+#define SRAM_LENGTH (16 * 1024) /**< The CC2538NF11 has 16 Kb of RAM */
+#else
+#define SRAM_LENGTH (32 * 1024) /**< All other existing models of the CC2538 have 32 Kb of RAM */
+#endif
+
/**
* manage the heap
*/
@@ -113,21 +120,25 @@ void _exit(int n)
* @brief Allocate memory from the heap.
*
* The current heap implementation is very rudimentary, it is only able to allocate
- * memory. But it does not
- * - check if the returned address is valid (no check if the memory very exists)
- * - have any means to free memory again
+ * memory. It does not have any means to free memory again.
*
- * TODO: check if the requested memory is really available
- *
- * @return [description]
+ * @return a pointer to the successfully allocated memory
+ * @return -1 on error, and errno is set to ENOMEM
*/
caddr_t _sbrk_r(struct _reent *r, size_t incr)
{
unsigned int state = disableIRQ();
- caddr_t res = heap_top;
- heap_top += incr;
- restoreIRQ(state);
- return res;
+ if ((uintptr_t)heap_top + incr > SRAM_BASE + SRAM_LENGTH) {
+ restoreIRQ(state);
+ r->_errno = ENOMEM;
+ return (caddr_t)-1;
+ }
+ else {
+ caddr_t res = heap_top;
+ heap_top += incr;
+ restoreIRQ(state);
+ return res;
+ }
}
/**
--
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