29 lines
716 B
C
29 lines
716 B
C
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#include <errno.h>
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#include <stdint.h>
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static uint8_t *__sbrk_heap_end = NULL;
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void *_sbrk(ptrdiff_t incr)
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{
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extern uint8_t _end; /* Symbol defined in the linker script */
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extern uint8_t _estack; /* Symbol defined in the linker script */
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extern uint32_t _Min_Stack_Size; /* Symbol defined in the linker script */
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const uint32_t stack_limit = (uint32_t)&_estack - (uint32_t)&_Min_Stack_Size;
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const uint8_t *max_heap = (uint8_t *)stack_limit;
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uint8_t *prev_heap_end;
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if (NULL == __sbrk_heap_end) {
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__sbrk_heap_end = &_end;
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}
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if (__sbrk_heap_end + incr > max_heap) {
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errno = ENOMEM;
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return (void *)-1;
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}
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prev_heap_end = __sbrk_heap_end;
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__sbrk_heap_end += incr;
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return (void *)prev_heap_end;
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}
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