// Copyright 2010 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. #include "runtime.h" #include "malloc.h" #include "os.h" extern byte end[]; static byte *bloc = { end }; enum { Round = 4095 }; void* runtime·SysAlloc(uintptr nbytes) { uintptr bl; // Plan 9 sbrk from /sys/src/libc/9sys/sbrk.c bl = ((uintptr)bloc + Round) & ~Round; if(runtime·brk_((void*)(bl + nbytes)) < 0) return (void*)-1; bloc = (byte*)bl + nbytes; return (void*)bl; } void runtime·SysFree(void *v, uintptr nbytes) { // from tiny/mem.c // Push pointer back if this is a free // of the most recent SysAlloc. nbytes += (nbytes + Round) & ~Round; if(bloc == (byte*)v+nbytes) bloc -= nbytes; } void runtime·SysUnused(void *v, uintptr nbytes) { USED(v, nbytes); } void runtime·SysMap(void *v, uintptr nbytes) { USED(v, nbytes); } void* runtime·SysReserve(void *v, uintptr nbytes) { USED(v); return runtime·SysAlloc(nbytes); }