/usr/lib/gcc/x86_64-linux-gnu/5/include/d/gc/os.d is in libphobos-5-dev 5.5.0-12ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 | /**
* Contains OS-level routines needed by the garbage collector.
*
* Copyright: Copyright Digital Mars 2005 - 2013.
* License: $(WEB www.boost.org/LICENSE_1_0.txt, Boost License 1.0).
* Authors: Walter Bright, David Friedman, Sean Kelly, Leandro Lucarella
*/
/* Copyright Digital Mars 2005 - 2013.
* Distributed under the Boost Software License, Version 1.0.
* (See accompanying file LICENSE or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*/
module gc.os;
version (Windows)
{
import core.sys.windows.windows;
alias int pthread_t;
pthread_t pthread_self() nothrow
{
return cast(pthread_t) GetCurrentThreadId();
}
//version = GC_Use_Alloc_Win32;
}
else version (Posix)
{
import core.sys.posix.sys.mman;
version (FreeBSD) import core.sys.freebsd.sys.mman : MAP_ANON;
version (CRuntime_Glibc) import core.sys.linux.sys.mman : MAP_ANON;
version (OSX) import core.sys.osx.sys.mman : MAP_ANON;
import core.stdc.stdlib;
//version = GC_Use_Alloc_MMap;
}
else
{
import core.stdc.stdlib;
//version = GC_Use_Alloc_Malloc;
}
/+
static if(is(typeof(VirtualAlloc)))
version = GC_Use_Alloc_Win32;
else static if (is(typeof(mmap)))
version = GC_Use_Alloc_MMap;
else static if (is(typeof(valloc)))
version = GC_Use_Alloc_Valloc;
else static if (is(typeof(malloc)))
version = GC_Use_Alloc_Malloc;
else static assert(false, "No supported allocation methods available.");
+/
static if (is(typeof(VirtualAlloc))) // version (GC_Use_Alloc_Win32)
{
/**
* Map memory.
*/
void *os_mem_map(size_t nbytes) nothrow
{
return VirtualAlloc(null, nbytes, MEM_RESERVE | MEM_COMMIT,
PAGE_READWRITE);
}
/**
* Unmap memory allocated with os_mem_map().
* Returns:
* 0 success
* !=0 failure
*/
int os_mem_unmap(void *base, size_t nbytes) nothrow
{
return cast(int)(VirtualFree(base, 0, MEM_RELEASE) == 0);
}
}
else static if (is(typeof(mmap))) // else version (GC_Use_Alloc_MMap)
{
void *os_mem_map(size_t nbytes) nothrow
{ void *p;
p = mmap(null, nbytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
return (p == MAP_FAILED) ? null : p;
}
int os_mem_unmap(void *base, size_t nbytes) nothrow
{
return munmap(base, nbytes);
}
}
else static if (is(typeof(valloc))) // else version (GC_Use_Alloc_Valloc)
{
void *os_mem_map(size_t nbytes) nothrow
{
return valloc(nbytes);
}
int os_mem_unmap(void *base, size_t nbytes) nothrow
{
free(base);
return 0;
}
}
else static if (is(typeof(malloc))) // else version (GC_Use_Alloc_Malloc)
{
// NOTE: This assumes malloc granularity is at least (void*).sizeof. If
// (req_size + PAGESIZE) is allocated, and the pointer is rounded up
// to PAGESIZE alignment, there will be space for a void* at the end
// after PAGESIZE bytes used by the GC.
import gc.gc;
const size_t PAGE_MASK = PAGESIZE - 1;
void *os_mem_map(size_t nbytes) nothrow
{ byte *p, q;
p = cast(byte *) malloc(nbytes + PAGESIZE);
q = p + ((PAGESIZE - ((cast(size_t) p & PAGE_MASK))) & PAGE_MASK);
* cast(void**)(q + nbytes) = p;
return q;
}
int os_mem_unmap(void *base, size_t nbytes) nothrow
{
free( *cast(void**)( cast(byte*) base + nbytes ) );
return 0;
}
}
else
{
static assert(false, "No supported allocation methods available.");
}
/**
Check for any kind of memory pressure.
Params:
mapped = the amount of memory mapped by the GC in bytes
Returns:
true if memory is scarce
*/
// TOOD: get virtual mem sizes and current usage from OS
// TODO: compare current RSS and avail. physical memory
version (Windows)
{
bool isLowOnMem(size_t mapped) nothrow @nogc
{
version (D_LP64)
return false;
else
{
import core.sys.windows.windows;
MEMORYSTATUS stat;
GlobalMemoryStatus(&stat);
// Less than 5 % of virtual address space available
return stat.dwAvailVirtual < stat.dwTotalVirtual / 20;
}
}
}
else version (OSX)
{
bool isLowOnMem(size_t mapped) nothrow @nogc
{
enum GB = 2 ^^ 30;
version (D_LP64)
return false;
else
{
// 80 % of available 4GB is used for GC (excluding malloc and mmap)
enum size_t limit = 4UL * GB * 8 / 10;
return mapped > limit;
}
}
}
else
{
bool isLowOnMem(size_t mapped) nothrow @nogc
{
enum GB = 2 ^^ 30;
version (D_LP64)
return false;
else
{
// be conservative and assume 3GB
enum size_t limit = 3UL * GB * 8 / 10;
return mapped > limit;
}
}
}
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