1 files changed, 79 insertions, 0 deletions
diff --git a/stm32f091/esp/Src/sysmem.c b/stm32f091/esp/Src/sysmem.c
new file mode 100644
index 0000000..54081ac
--- /dev/null
+++ b/stm32f091/esp/Src/sysmem.c
@@ -0,0 +1,79 @@
+/**
+ ******************************************************************************
+ * @file      sysmem.c
+ * @author    Generated by STM32CubeIDE
+ * @brief     STM32CubeIDE System Memory calls file
+ *
+ *            For more information about which C functions
+ *            need which of these lowlevel functions
+ *            please consult the newlib libc manual
+ ******************************************************************************
+ * @attention
+ *
+ * Copyright (c) 2022 STMicroelectronics.
+ * All rights reserved.
+ *
+ * This software is licensed under terms that can be found in the LICENSE file
+ * in the root directory of this software component.
+ * If no LICENSE file comes with this software, it is provided AS-IS.
+ *
+ ******************************************************************************
+ */
+
+/* Includes */
+#include <errno.h>
+#include <stdint.h>
+
+/**
+ * Pointer to the current high watermark of the heap usage
+ */
+static uint8_t *__sbrk_heap_end = NULL;
+
+/**
+ * @brief _sbrk() allocates memory to the newlib heap and is used by malloc
+ *        and others from the C library
+ *
+ * @verbatim
+ * ############################################################################
+ * #  .data  #  .bss  #       newlib heap       #          MSP stack          #
+ * #         #        #                         # Reserved by _Min_Stack_Size #
+ * ############################################################################
+ * ^-- RAM start      ^-- _end                             _estack, RAM end --^
+ * @endverbatim
+ *
+ * This implementation starts allocating at the '_end' linker symbol
+ * The '_Min_Stack_Size' linker symbol reserves a memory for the MSP stack
+ * The implementation considers '_estack' linker symbol to be RAM end
+ * NOTE: If the MSP stack, at any point during execution, grows larger than the
+ * reserved size, please increase the '_Min_Stack_Size'.
+ *
+ * @param incr Memory size
+ * @return Pointer to allocated memory
+ */
+void *_sbrk(ptrdiff_t incr)
+{
+  extern uint8_t _end; /* Symbol defined in the linker script */
+  extern uint8_t _estack; /* Symbol defined in the linker script */
+  extern uint32_t _Min_Stack_Size; /* Symbol defined in the linker script */
+  const uint32_t stack_limit = (uint32_t)&_estack - (uint32_t)&_Min_Stack_Size;
+  const uint8_t *max_heap = (uint8_t *)stack_limit;
+  uint8_t *prev_heap_end;
+
+  /* Initialize heap end at first call */
+  if (NULL == __sbrk_heap_end)
+  {
+    __sbrk_heap_end = &_end;
+  }
+
+  /* Protect heap from growing into the reserved MSP stack */
+  if (__sbrk_heap_end + incr > max_heap)
+  {
+    errno = ENOMEM;
+    return (void *)-1;
+  }
+
+  prev_heap_end = __sbrk_heap_end;
+  __sbrk_heap_end += incr;
+
+  return (void *)prev_heap_end;
+}