newlib-cygwin/winsup/cygwin/shared.cc

432 lines
12 KiB
C++

/* shared.cc: shared data area support.
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
2006, 2007, 2008 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include "miscfuncs.h"
#include <unistd.h>
#include "cygerrno.h"
#include "pinfo.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "heap.h"
#include "shared_info_magic.h"
#include "registry.h"
#include "cygwin_version.h"
#include "pwdgrp.h"
#include "ntdll.h"
#include <alloca.h>
#include <wchar.h>
shared_info NO_COPY *cygwin_shared;
user_info NO_COPY *user_shared;
HANDLE NO_COPY cygwin_shared_h;
HANDLE NO_COPY cygwin_user_h;
/* This function returns a handle to the top-level directory in the global
NT namespace used to implement global objects including shared memory. */
extern bool _cygwin_testing;
HANDLE
get_shared_parent_dir ()
{
static HANDLE dir;
UNICODE_STRING uname;
OBJECT_ATTRIBUTES attr;
NTSTATUS status;
if (!dir)
{
WCHAR bnoname[MAX_PATH];
__small_swprintf (bnoname, L"\\BaseNamedObjects\\%s%s",
cygwin_version.shared_id,
_cygwin_testing ? cygwin_version.dll_build_date : "");
RtlInitUnicodeString (&uname, bnoname);
InitializeObjectAttributes (&attr, &uname, OBJ_INHERIT | OBJ_OPENIF,
NULL, everyone_sd (CYG_SHARED_DIR_ACCESS));
status = NtCreateDirectoryObject (&dir, CYG_SHARED_DIR_ACCESS, &attr);
if (!NT_SUCCESS (status))
api_fatal ("NtCreateDirectoryObject(%S): %p", &uname, status);
}
return dir;
}
HANDLE
get_session_parent_dir ()
{
static HANDLE dir;
UNICODE_STRING uname;
OBJECT_ATTRIBUTES attr;
NTSTATUS status;
if (!dir)
{
PROCESS_SESSION_INFORMATION psi;
status = NtQueryInformationProcess (GetCurrentProcess (),
ProcessSessionInformation,
&psi, sizeof psi, NULL);
if (!NT_SUCCESS (status) || psi.SessionId == 0)
dir = get_shared_parent_dir ();
else
{
WCHAR bnoname[MAX_PATH];
__small_swprintf (bnoname,
L"\\Sessions\\BNOLINKS\\%d\\%s%s",
psi.SessionId, cygwin_version.shared_id,
_cygwin_testing ? cygwin_version.dll_build_date : "");
RtlInitUnicodeString (&uname, bnoname);
InitializeObjectAttributes (&attr, &uname, OBJ_INHERIT | OBJ_OPENIF,
NULL, everyone_sd(CYG_SHARED_DIR_ACCESS));
status = NtCreateDirectoryObject (&dir, CYG_SHARED_DIR_ACCESS, &attr);
if (!NT_SUCCESS (status))
api_fatal ("NtCreateDirectoryObject(%S): %p", &uname, status);
}
}
return dir;
}
char * __stdcall
shared_name (char *ret_buf, const char *str, int num)
{
__small_sprintf (ret_buf, "%s.%d", str, num);
return ret_buf;
}
#define page_const (65535)
#define pround(n) (((size_t) (n) + page_const) & ~page_const)
static ptrdiff_t offsets[] =
{
- pround (sizeof (shared_info))
- pround (sizeof (user_info))
- pround (sizeof (console_state))
- pround (sizeof (_pinfo)),
- pround (sizeof (user_info))
- pround (sizeof (console_state))
- pround (sizeof (_pinfo)),
- pround (sizeof (console_state))
- pround (sizeof (_pinfo)),
- pround (sizeof (_pinfo)),
0
};
#define off_addr(x) ((void *)((caddr_t) cygwin_hmodule + offsets[x]))
void * __stdcall
open_shared (const char *name, int n, HANDLE& shared_h, DWORD size,
shared_locations& m, PSECURITY_ATTRIBUTES psa, DWORD access)
{
void *shared;
void *addr;
if (m == SH_JUSTCREATE || m == SH_JUSTOPEN)
addr = NULL;
else
{
addr = off_addr (m);
VirtualFree (addr, 0, MEM_RELEASE);
}
char map_buf[MAX_PATH];
char *mapname = NULL;
if (shared_h)
m = SH_JUSTOPEN;
else
{
if (name)
mapname = shared_name (map_buf, name, n);
if (m == SH_JUSTOPEN)
shared_h = OpenFileMapping (access, FALSE, mapname);
else
{
shared_h = CreateFileMapping (INVALID_HANDLE_VALUE, psa,
PAGE_READWRITE, 0, size, mapname);
if (GetLastError () == ERROR_ALREADY_EXISTS)
m = SH_JUSTOPEN;
}
if (shared_h)
/* ok! */;
else if (m != SH_JUSTOPEN)
api_fatal ("CreateFileMapping %s, %E. Terminating.", mapname);
else
return NULL;
}
shared = (shared_info *)
MapViewOfFileEx (shared_h, access, 0, 0, 0, addr);
if (!shared && addr)
{
shared = (shared_info *) MapViewOfFileEx (shared_h,
FILE_MAP_READ|FILE_MAP_WRITE,
0, 0, 0, NULL);
#ifdef DEBUGGING
system_printf ("relocating shared object %s(%d) from %p to %p", name, n, addr, shared);
#endif
offsets[0] = 0;
}
if (!shared)
api_fatal ("MapViewOfFileEx '%s'(%p), %E. Terminating.", mapname, shared_h);
if (m == SH_CYGWIN_SHARED && offsets[0])
{
ptrdiff_t delta = (caddr_t) shared - (caddr_t) off_addr (0);
offsets[0] = (caddr_t) shared - (caddr_t) cygwin_hmodule;
for (int i = SH_USER_SHARED + 1; i < SH_TOTAL_SIZE; i++)
{
unsigned size = offsets[i + 1] - offsets[i];
offsets[i] += delta;
if (!VirtualAlloc (off_addr (i), size, MEM_RESERVE, PAGE_NOACCESS))
continue; /* oh well */
}
offsets[SH_TOTAL_SIZE] += delta;
}
debug_printf ("name %s, n %d, shared %p (wanted %p), h %p", mapname, n, shared, addr, shared_h);
return shared;
}
/* Second half of user shared initialization: Initialize content. */
void
user_shared_initialize ()
{
DWORD sversion = (DWORD) InterlockedExchange ((LONG *) &user_shared->version, USER_VERSION_MAGIC);
/* Wait for initialization of the Cygwin per-user shared, if necessary */
if (!sversion)
{
cygpsid sid (cygheap->user.sid ());
struct passwd *pw = internal_getpwsid (sid);
/* Correct the user name with what's defined in /etc/passwd before
loading the user fstab file. */
if (pw)
cygheap->user.set_name (pw->pw_name);
user_shared->mountinfo.init (); /* Initialize the mount table. */
user_shared->cb = sizeof (*user_shared);
}
else
{
while (!user_shared->cb)
low_priority_sleep (0); // Should be hit only very very rarely
if (user_shared->version != sversion)
multiple_cygwin_problem ("user shared memory version", user_shared->version, sversion);
else if (user_shared->cb != sizeof (*user_shared))
multiple_cygwin_problem ("user shared memory size", user_shared->cb, sizeof (*user_shared));
}
}
/* First half of user shared initialization: Create shared mem region. */
void
user_shared_create (bool reinit)
{
char name[UNLEN + 1] = ""; /* Large enough for SID */
if (reinit)
{
if (!UnmapViewOfFile (user_shared))
debug_printf("UnmapViewOfFile %E");
if (!ForceCloseHandle (cygwin_user_h))
debug_printf("CloseHandle %E");
cygwin_user_h = NULL;
}
if (!cygwin_user_h)
cygheap->user.get_windows_id (name);
shared_locations sh_user_shared = SH_USER_SHARED;
user_shared = (user_info *) open_shared (name, USER_VERSION,
cygwin_user_h, sizeof (user_info),
sh_user_shared, &sec_none);
debug_printf ("opening user shared for '%s' at %p", name, user_shared);
ProtectHandleINH (cygwin_user_h);
debug_printf ("user shared version %x", user_shared->version);
if (reinit)
user_shared_initialize ();
}
void __stdcall
shared_destroy ()
{
ForceCloseHandle (cygwin_shared_h);
UnmapViewOfFile (cygwin_shared);
ForceCloseHandle (cygwin_user_h);
UnmapViewOfFile (user_shared);
}
/* Use absolute path of cygwin1.dll to derive the Win32 dir which
is our installation root. Note that we can't handle Cygwin installation
root dirs of more than 4K path length. I assume that's ok... */
void
shared_info::init_installation_root ()
{
if (!GetModuleFileNameW (cygwin_hmodule, installation_root, PATH_MAX))
api_fatal ("Can't initialize Cygwin installation root dir.\n"
"GetModuleFileNameW(%p, %p, %u), %E",
cygwin_hmodule, installation_root, PATH_MAX);
PWCHAR p = installation_root;
if (wcsncmp (p, L"\\\\?\\", 4)) /* No long path prefix. */
{
if (!wcsncasecmp (p, L"\\\\", 2)) /* UNC */
{
p = wcpcpy (p, L"\\??\\UN");
GetModuleFileNameW (cygwin_hmodule, p, PATH_MAX - 6);
*p = L'C';
}
else
{
p = wcpcpy (p, L"\\??\\");
GetModuleFileNameW (cygwin_hmodule, p, PATH_MAX - 4);
}
}
installation_root[1] = L'?';
PWCHAR w = wcsrchr (installation_root, L'\\');
if (w)
{
*w = L'\0';
w = wcsrchr (installation_root, L'\\');
}
if (!w)
api_fatal ("Can't initialize Cygwin installation root dir.\n"
"Invalid DLL path");
*w = L'\0';
}
/* Initialize obcaseinsensitive. Default to case insensitive on pre-XP. */
void
shared_info::init_obcaseinsensitive ()
{
HKEY key;
DWORD size = sizeof (DWORD);
obcaseinsensitive = 1;
if (RegOpenKeyEx (HKEY_LOCAL_MACHINE,
"SYSTEM\\CurrentControlSet\\Control\\Session Manager\\kernel",
0, KEY_READ, &key) == ERROR_SUCCESS)
{
RegQueryValueEx (key, "obcaseinsensitive", NULL, NULL,
(LPBYTE) &obcaseinsensitive, &size);
RegCloseKey (key);
}
debug_printf ("obcaseinsensitive set to %d", obcaseinsensitive);
}
void
shared_info::initialize ()
{
DWORD sversion = (DWORD) InterlockedExchange ((LONG *) &version, SHARED_VERSION_MAGIC);
if (sversion)
{
if (sversion != SHARED_VERSION_MAGIC)
{
InterlockedExchange ((LONG *) &version, sversion);
multiple_cygwin_problem ("system shared memory version", sversion, SHARED_VERSION_MAGIC);
}
while (!cb)
low_priority_sleep (0); // Should be hit only very very rarely
}
heap_init ();
get_session_parent_dir (); /* Create session dir if first process. */
if (!sversion)
{
init_installation_root ();/* Initialize installation root dir. */
init_obcaseinsensitive ();/* Initialize obcaseinsensitive. */
tty.init (); /* Initialize tty table. */
mt.initialize (); /* Initialize shared tape information. */
cb = sizeof (*this); /* Do last, after all shared memory initialization */
}
if (cb != SHARED_INFO_CB)
system_printf ("size of shared memory region changed from %u to %u",
SHARED_INFO_CB, cb);
}
void __stdcall
memory_init ()
{
getpagesize ();
/* Initialize the Cygwin heap, if necessary */
if (!cygheap)
{
cygheap_init ();
cygheap->user.init ();
}
/* Initialize general shared memory */
shared_locations sh_cygwin_shared;
cygwin_shared = (shared_info *) open_shared ("shared",
CYGWIN_VERSION_SHARED_DATA,
cygwin_shared_h,
sizeof (*cygwin_shared),
sh_cygwin_shared = SH_CYGWIN_SHARED);
cygwin_shared->initialize ();
user_shared_create (false);
}
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;
}