28 lines
693 B
C
28 lines
693 B
C
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#include <machine/syscall.h>
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#include <sys/types.h>
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#include "internal_syscall.h"
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/* Increase program data space. As malloc and related functions depend
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on this, it is useful to have a working implementation. The following
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is suggested by the newlib docs and suffices for a standalone
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system. */
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void *
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_sbrk(ptrdiff_t incr)
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{
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static unsigned long heap_end;
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if (heap_end == 0)
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{
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long brk = syscall_errno (SYS_brk, 0, 0, 0, 0, 0, 0);
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if (brk == -1)
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return (void *)-1;
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heap_end = brk;
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}
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if (syscall_errno (SYS_brk, heap_end + incr, 0, 0, 0, 0, 0) != heap_end + incr)
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return (void *)-1;
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heap_end += incr;
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return (void *)(heap_end - incr);
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}
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