493 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			493 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/* shared.cc: shared data area support.
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   Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
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   2006, 2007, 2008, 2009 Red Hat, Inc.
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This file is part of Cygwin.
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This software is a copyrighted work licensed under the terms of the
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Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
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details. */
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#include "winsup.h"
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#include "miscfuncs.h"
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#include <unistd.h>
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#include "cygerrno.h"
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#include "pinfo.h"
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#include "path.h"
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#include "fhandler.h"
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#include "dtable.h"
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#include "cygheap.h"
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#include "heap.h"
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#include "shared_info_magic.h"
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#include "registry.h"
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#include "cygwin_version.h"
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#include "pwdgrp.h"
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#include "spinlock.h"
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#include <alloca.h>
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#include <wchar.h>
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#include <wingdi.h>
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#include <winuser.h>
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shared_info NO_COPY *cygwin_shared;
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user_info NO_COPY *user_shared;
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HANDLE NO_COPY cygwin_shared_h;
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HANDLE NO_COPY cygwin_user_h;
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WCHAR installation_root[PATH_MAX] __attribute__((section (".cygwin_dll_common"), shared));
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UNICODE_STRING installation_key __attribute__((section (".cygwin_dll_common"), shared));
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WCHAR installation_key_buf[18] __attribute__((section (".cygwin_dll_common"), shared));
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static LONG installation_root_inited __attribute__((section (".cygwin_dll_common"), shared));
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#define SPIN_WAIT 10000
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/* Use absolute path of cygwin1.dll to derive the Win32 dir which
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   is our installation_root.  Note that we can't handle Cygwin installation
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   root dirs of more than 4K path length.  I assume that's ok...
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   This function also generates the installation_key value.  It's a 64 bit
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   hash value based on the path of the Cygwin DLL itself.  It's subsequently
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   used when generating shared object names.  Thus, different Cygwin
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   installations generate different object names and so are isolated from
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   each other.
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   Having this information, the installation key together with the
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   installation root path is written to the registry.  The idea is that
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   cygcheck can print the paths into which the Cygwin DLL has been
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   installed for debugging purposes.
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   Last but not least, the new cygwin properties datastrcuture is checked
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   for the "disabled_key" value, which is used to determine whether the
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   installation key is actually added to all object names or not.  This is
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   used as a last resort for debugging purposes, usually.  However, there
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   could be another good reason to re-enable object name collisions between
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   multiple Cygwin DLLs, which we're just not aware of right now.  Cygcheck
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   can be used to change the value in an existing Cygwin DLL binary. */
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void inline
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init_installation_root ()
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{
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  spinlock iri (installation_root_inited);
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  if (!iri)
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    {
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      if (!GetModuleFileNameW (cygwin_hmodule, installation_root, PATH_MAX))
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	api_fatal ("Can't initialize Cygwin installation root dir.\n"
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		   "GetModuleFileNameW(%p, %p, %u), %E",
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		   cygwin_hmodule, installation_root, PATH_MAX);
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      PWCHAR p = installation_root;
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      if (wcsncmp (p, L"\\\\?\\", 4))	/* No long path prefix. */
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	{
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	  if (!wcsncasecmp (p, L"\\\\", 2))	/* UNC */
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	    {
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	      p = wcpcpy (p, L"\\??\\UN");
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	      GetModuleFileNameW (cygwin_hmodule, p, PATH_MAX - 6);
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	      *p = L'C';
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	    }
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	  else
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	    {
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	      p = wcpcpy (p, L"\\??\\");
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	      GetModuleFileNameW (cygwin_hmodule, p, PATH_MAX - 4);
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	    }
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	}
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      installation_root[1] = L'?';
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      RtlInitEmptyUnicodeString (&installation_key, installation_key_buf,
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				 sizeof installation_key_buf);
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      RtlInt64ToHexUnicodeString (hash_path_name (0, installation_root),
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				  &installation_key, FALSE);
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      PWCHAR w = wcsrchr (installation_root, L'\\');
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      if (w)
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	{
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	  *w = L'\0';
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	  w = wcsrchr (installation_root, L'\\');
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	}
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      if (!w)
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	api_fatal ("Can't initialize Cygwin installation root dir.\n"
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		   "Invalid DLL path");
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      *w = L'\0';
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      for (int i = 1; i >= 0; --i)
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	{
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	  reg_key r (i, KEY_WRITE, CYGWIN_INFO_INSTALLATIONS_NAME, NULL);
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	  if (r.set_string (installation_key_buf, installation_root)
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	      == ERROR_SUCCESS)
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	    break;
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	}
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      if (cygwin_props.disable_key)
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	{
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	  installation_key.Length = 0;
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	  installation_key.Buffer[0] = L'\0';
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	}
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    }
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}
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/* This function returns a handle to the top-level directory in the global
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   NT namespace used to implement global objects including shared memory. */
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HANDLE
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get_shared_parent_dir ()
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{
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  static HANDLE dir;
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  UNICODE_STRING uname;
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  OBJECT_ATTRIBUTES attr;
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  NTSTATUS status;
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  if (!dir)
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    {
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      WCHAR bnoname[MAX_PATH];
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      __small_swprintf (bnoname, L"\\BaseNamedObjects\\%s%s-%S",
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			cygwin_version.shared_id,
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			_cygwin_testing ? cygwin_version.dll_build_date : "",
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			&installation_key);
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      RtlInitUnicodeString (&uname, bnoname);
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      InitializeObjectAttributes (&attr, &uname, OBJ_INHERIT | OBJ_OPENIF,
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				  NULL, everyone_sd (CYG_SHARED_DIR_ACCESS));
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      status = NtCreateDirectoryObject (&dir, CYG_SHARED_DIR_ACCESS, &attr);
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      if (!NT_SUCCESS (status))
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	api_fatal ("NtCreateDirectoryObject(%S): %p", &uname, status);
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    }
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  return dir;
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}
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HANDLE
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get_session_parent_dir ()
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{
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  static HANDLE dir;
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  UNICODE_STRING uname;
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  OBJECT_ATTRIBUTES attr;
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  NTSTATUS status;
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  if (!dir)
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    {
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      PROCESS_SESSION_INFORMATION psi;
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      status = NtQueryInformationProcess (NtCurrentProcess (),
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					  ProcessSessionInformation,
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					  &psi, sizeof psi, NULL);
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      if (!NT_SUCCESS (status) || psi.SessionId == 0)
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	dir = get_shared_parent_dir ();
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      else
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	{
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	  WCHAR bnoname[MAX_PATH];
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	  __small_swprintf (bnoname,
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			    L"\\Sessions\\BNOLINKS\\%d\\%s%s-%S",
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			    psi.SessionId, cygwin_version.shared_id,
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			    _cygwin_testing ? cygwin_version.dll_build_date : "",
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			    &installation_key);
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	  RtlInitUnicodeString (&uname, bnoname);
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	  InitializeObjectAttributes (&attr, &uname, OBJ_INHERIT | OBJ_OPENIF,
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				      NULL, everyone_sd(CYG_SHARED_DIR_ACCESS));
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	  status = NtCreateDirectoryObject (&dir, CYG_SHARED_DIR_ACCESS, &attr);
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	  if (!NT_SUCCESS (status))
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	    api_fatal ("NtCreateDirectoryObject(%S): %p", &uname, status);
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	}
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    }
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  return dir;
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}
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char * __stdcall
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shared_name (char *ret_buf, const char *str, int num)
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{
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  __small_sprintf (ret_buf, "%s.%d", str, num);
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  return ret_buf;
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}
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WCHAR * __stdcall
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shared_name (WCHAR *ret_buf, const WCHAR *str, int num)
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{
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  __small_swprintf (ret_buf, L"%W.%d", str, num);
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  return ret_buf;
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}
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#define page_const (65535)
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#define pround(n) (((size_t) (n) + page_const) & ~page_const)
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static ptrdiff_t offsets[] =
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{
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  - pround (sizeof (shared_info))
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  - pround (sizeof (user_info))
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  - pround (sizeof (console_state))
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  - pround (sizeof (_pinfo)),
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  - pround (sizeof (user_info))
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  - pround (sizeof (console_state))
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  - pround (sizeof (_pinfo)),
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  - pround (sizeof (console_state))
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  - pround (sizeof (_pinfo)),
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  - pround (sizeof (_pinfo)),
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  0
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};
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#define off_addr(x)	((void *)((caddr_t) cygwin_hmodule + offsets[x]))
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void * __stdcall
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open_shared (const WCHAR *name, int n, HANDLE& shared_h, DWORD size,
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	     shared_locations m, PSECURITY_ATTRIBUTES psa, DWORD access)
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{
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  return open_shared (name, n, shared_h, size, &m, psa, access);
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}
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void * __stdcall
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open_shared (const WCHAR *name, int n, HANDLE& shared_h, DWORD size,
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	     shared_locations *m, PSECURITY_ATTRIBUTES psa, DWORD access)
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{
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  void *shared;
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  void *addr;
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  if (*m == SH_JUSTCREATE || *m == SH_JUSTOPEN)
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    addr = NULL;
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  else
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    {
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      addr = off_addr (*m);
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      VirtualFree (addr, 0, MEM_RELEASE);
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    }
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  WCHAR map_buf[MAX_PATH];
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  WCHAR *mapname = NULL;
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  if (shared_h)
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    *m = SH_JUSTOPEN;
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  else
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    {
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      if (name)
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	mapname = shared_name (map_buf, name, n);
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      if (*m == SH_JUSTOPEN)
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	shared_h = OpenFileMappingW (access, FALSE, mapname);
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      else
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	{
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	  shared_h = CreateFileMappingW (INVALID_HANDLE_VALUE, psa,
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					PAGE_READWRITE, 0, size, mapname);
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	  if (GetLastError () == ERROR_ALREADY_EXISTS)
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	    *m = SH_JUSTOPEN;
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	}
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      if (shared_h)
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	/* ok! */;
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      else if (*m != SH_JUSTOPEN)
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	api_fatal ("CreateFileMapping %W, %E.  Terminating.", mapname);
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      else
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	return NULL;
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    }
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  shared = (shared_info *)
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    MapViewOfFileEx (shared_h, access, 0, 0, 0, addr);
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  if (!shared && addr)
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    {
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      shared = (shared_info *) MapViewOfFileEx (shared_h,
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				       FILE_MAP_READ|FILE_MAP_WRITE,
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				       0, 0, 0, NULL);
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#ifdef DEBUGGING
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      system_printf ("relocating shared object %W(%d) from %p to %p", name, n, addr, shared);
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#endif
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      offsets[0] = 0;
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    }
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  if (!shared)
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    api_fatal ("MapViewOfFileEx '%W'(%p), %E.  Terminating.", mapname, shared_h);
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  if (*m == SH_CYGWIN_SHARED && offsets[0])
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    {
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      ptrdiff_t delta = (caddr_t) shared - (caddr_t) off_addr (0);
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      offsets[0] = (caddr_t) shared - (caddr_t) cygwin_hmodule;
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      for (int i = SH_USER_SHARED + 1; i < SH_TOTAL_SIZE; i++)
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	{
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	  unsigned size = offsets[i + 1] - offsets[i];
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	  offsets[i] += delta;
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	  if (!VirtualAlloc (off_addr (i), size, MEM_RESERVE, PAGE_NOACCESS))
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	    continue;  /* oh well */
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	}
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      offsets[SH_TOTAL_SIZE] += delta;
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    }
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  debug_printf ("name %W, n %d, shared %p (wanted %p), h %p", mapname, n, shared, addr, shared_h);
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  return shared;
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}
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/* Second half of user shared initialization: Initialize content. */
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void
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user_info::initialize ()
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{
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  /* Wait for initialization of the Cygwin per-user shared, if necessary */
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  spinlock sversion (version, CURR_USER_MAGIC);
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  if (!sversion)
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    {
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      cb =  sizeof (*user_shared);
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      cygpsid sid (cygheap->user.sid ());
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      struct passwd *pw = internal_getpwsid (sid);
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      /* Correct the user name with what's defined in /etc/passwd before
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	 loading the user fstab file. */
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      if (pw)
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	cygheap->user.set_name (pw->pw_name);
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      mountinfo.init ();	/* Initialize the mount table.  */
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    }
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  else if (sversion != CURR_USER_MAGIC)
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    sversion.multiple_cygwin_problem ("user shared memory version", version,
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				      sversion);
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  else if (user_shared->cb != sizeof (*user_shared))
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    sversion.multiple_cygwin_problem ("user shared memory size", cb,
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				      sizeof (*user_shared));
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}
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/* First half of user shared initialization: Create shared mem region. */
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void
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user_info::create (bool reinit)
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{
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  WCHAR name[UNLEN + 1] = L""; /* Large enough for SID */
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  if (reinit)
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    {
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      if (!UnmapViewOfFile (user_shared))
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	debug_printf("UnmapViewOfFile %E");
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      if (!ForceCloseHandle (cygwin_user_h))
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	debug_printf("CloseHandle %E");
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      cygwin_user_h = NULL;
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    }
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  if (!cygwin_user_h)
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    cygheap->user.get_windows_id (name);
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  user_shared = (user_info *) open_shared (name, USER_VERSION,
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					   cygwin_user_h, sizeof (user_info),
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					   SH_USER_SHARED, &sec_none);
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  debug_printf ("opening user shared for '%W' at %p", name, user_shared);
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  ProtectHandleINH (cygwin_user_h);
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  debug_printf ("user shared version %x", user_shared->version);
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  if (reinit)
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    user_shared->initialize ();
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}
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void __stdcall
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shared_destroy ()
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{
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  ForceCloseHandle (cygwin_shared_h);
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  UnmapViewOfFile (cygwin_shared);
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  ForceCloseHandle (cygwin_user_h);
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  UnmapViewOfFile (user_shared);
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}
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/* Initialize obcaseinsensitive.  Default to case insensitive on pre-XP. */
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void
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shared_info::init_obcaseinsensitive ()
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{
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  HKEY key;
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  DWORD size = sizeof (DWORD);
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  obcaseinsensitive = 1;
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  if (RegOpenKeyEx (HKEY_LOCAL_MACHINE,
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		  "SYSTEM\\CurrentControlSet\\Control\\Session Manager\\kernel",
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		  0, KEY_READ, &key) == ERROR_SUCCESS)
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    {
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      RegQueryValueEx (key, "obcaseinsensitive", NULL, NULL,
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		       (LPBYTE) &obcaseinsensitive, &size);
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      RegCloseKey (key);
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    }
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  debug_printf ("obcaseinsensitive set to %d", obcaseinsensitive);
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}
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void inline
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shared_info::create ()
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{
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  cygwin_shared = (shared_info *) open_shared (L"shared",
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					       CYGWIN_VERSION_SHARED_DATA,
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					       cygwin_shared_h,
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					       sizeof (*cygwin_shared),
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					       SH_CYGWIN_SHARED);
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  cygwin_shared->initialize ();
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}
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void
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shared_info::initialize ()
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{
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  spinlock sversion (version, CURR_SHARED_MAGIC);
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  if (!sversion)
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    {
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      cb = sizeof (*this);
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      get_session_parent_dir ();	/* Create session dir if first process. */
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      init_obcaseinsensitive ();	/* Initialize obcaseinsensitive */
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      tty.init ();			/* Initialize tty table  */
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      mt.initialize ();			/* Initialize shared tape information */
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      /* Defer debug output printing the installation root and installation key
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	 up to this point.  Debug output except for system_printf requires
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	 the global shared memory to exist. */
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      debug_printf ("Installation root: <%W> key: <%S>",
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		    installation_root, &installation_key);
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    }
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  else if (sversion != (LONG) CURR_SHARED_MAGIC)
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    sversion.multiple_cygwin_problem ("system shared memory version",
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				      sversion, CURR_SHARED_MAGIC);
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  else if (cb != sizeof (*this))
 | 
						|
    system_printf ("size of shared memory region changed from %u to %u",
 | 
						|
		   sizeof (*this), cb);
 | 
						|
  heap_init ();
 | 
						|
}
 | 
						|
 | 
						|
void
 | 
						|
memory_init (bool init_cygheap)
 | 
						|
{
 | 
						|
  getpagesize ();
 | 
						|
 | 
						|
  /* Initialize the Cygwin heap, if necessary */
 | 
						|
  if (init_cygheap)
 | 
						|
    {
 | 
						|
      cygheap_init ();
 | 
						|
      cygheap->user.init ();
 | 
						|
    }
 | 
						|
 | 
						|
  init_installation_root ();	/* Initialize installation root dir */
 | 
						|
  shared_info::create ();	/* Initialize global shared memory */
 | 
						|
  user_info::create (false);	/* Initialize per-user shared memory */
 | 
						|
}
 | 
						|
 | 
						|
unsigned
 | 
						|
shared_info::heap_slop_size ()
 | 
						|
{
 | 
						|
  if (!heap_slop_inited)
 | 
						|
    {
 | 
						|
      /* Fetch from registry, first user then local machine.  */
 | 
						|
      for (int i = 0; i < 2; i++)
 | 
						|
	{
 | 
						|
	  reg_key reg (i, KEY_READ, NULL);
 | 
						|
 | 
						|
	  if ((heap_slop = reg.get_int ("heap_slop_in_mb", 0)))
 | 
						|
	    break;
 | 
						|
	  heap_slop = wincap.heapslop ();
 | 
						|
	}
 | 
						|
      heap_slop <<= 20;
 | 
						|
      heap_slop_inited = true;
 | 
						|
    }
 | 
						|
 | 
						|
  return heap_slop;
 | 
						|
}
 | 
						|
 | 
						|
unsigned
 | 
						|
shared_info::heap_chunk_size ()
 | 
						|
{
 | 
						|
  if (!heap_chunk)
 | 
						|
    {
 | 
						|
      /* Fetch from registry, first user then local machine.  */
 | 
						|
      for (int i = 0; i < 2; i++)
 | 
						|
	{
 | 
						|
	  reg_key reg (i, KEY_READ, NULL);
 | 
						|
 | 
						|
	  /* Note that reserving a huge amount of heap space does not result in
 | 
						|
	     the use of swap since we are not committing it. */
 | 
						|
	  /* FIXME: We should not be restricted to a fixed size heap no matter
 | 
						|
	     what the fixed size is. */
 | 
						|
 | 
						|
	  if ((heap_chunk = reg.get_int ("heap_chunk_in_mb", 0)))
 | 
						|
	    break;
 | 
						|
	  heap_chunk = 384; /* Default */
 | 
						|
	}
 | 
						|
 | 
						|
      if (heap_chunk < 4)
 | 
						|
	heap_chunk = 4 * 1024 * 1024;
 | 
						|
      else
 | 
						|
	heap_chunk <<= 20;
 | 
						|
      if (!heap_chunk)
 | 
						|
	heap_chunk = 384 * 1024 * 1024;
 | 
						|
    }
 | 
						|
 | 
						|
  return heap_chunk;
 | 
						|
}
 |