newlib/winsup/cygwin/shared.cc

294 lines
7.9 KiB
C++

/* shared.cc: shared data area support.
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
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 <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <grp.h>
#include <pwd.h>
#include "cygerrno.h"
#include "pinfo.h"
#include "security.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 "child_info.h"
#include "mtinfo.h"
shared_info NO_COPY *cygwin_shared;
user_info NO_COPY *user_shared;
HANDLE NO_COPY cygwin_user_h;
char * __stdcall
shared_name (char *ret_buf, const char *str, int num)
{
extern bool _cygwin_testing;
__small_sprintf (ret_buf, "%s%s.%s.%d", cygheap->shared_prefix,
cygwin_version.shared_id, str, num);
if (_cygwin_testing)
strcat (ret_buf, cygwin_version.dll_build_date);
return ret_buf;
}
#define page_const (65535)
#define pround(n) (((size_t) (n) + page_const) & ~page_const)
static char *offsets[] =
{
(char *) cygwin_shared_address,
(char *) cygwin_shared_address
+ pround (sizeof (shared_info)),
(char *) cygwin_shared_address
+ pround (sizeof (shared_info))
+ pround (sizeof (user_info)),
(char *) cygwin_shared_address
+ pround (sizeof (shared_info))
+ pround (sizeof (user_info))
+ pround (sizeof (console_state)),
(char *) cygwin_shared_address
+ pround (sizeof (shared_info))
+ pround (sizeof (user_info))
+ pround (sizeof (console_state))
+ pround (sizeof (_pinfo)),
(char *) cygwin_shared_address
+ pround (sizeof (shared_info))
+ pround (sizeof (user_info))
+ pround (sizeof (console_state))
+ pround (sizeof (_pinfo))
+ pround (sizeof (mtinfo))
};
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)
|| !wincap.needs_memory_protection () && offsets[0])
addr = NULL;
else
{
addr = offsets[m];
(void) VirtualFree (addr, 0, MEM_RELEASE);
}
if (shared_h)
m = SH_JUSTOPEN;
else
{
char *mapname;
char map_buf[CYG_MAX_PATH];
if (!name)
mapname = NULL;
else
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)
{
/* Probably win95, so try without specifying the address. */
shared = (shared_info *) MapViewOfFileEx (shared_h,
FILE_MAP_READ|FILE_MAP_WRITE,
0, 0, 0, NULL);
#ifdef DEBUGGING
if (wincap.is_winnt ())
system_printf ("relocating shared object %s(%d) from %p to %p on Windows NT", name, n, addr, shared);
#endif
offsets[0] = NULL;
}
if (!shared)
api_fatal ("MapViewOfFileEx '%s'(%p), %E. Terminating.", name, shared_h);
if (m == SH_CYGWIN_SHARED && offsets[0] && wincap.needs_memory_protection ())
{
unsigned delta = (char *) shared - offsets[0];
offsets[0] = (char *) shared;
for (int i = SH_CYGWIN_SHARED + 1; i < SH_TOTAL_SIZE; i++)
{
unsigned size = offsets[i + 1] - offsets[i];
offsets[i] += delta;
if (!VirtualAlloc (offsets[i], size, MEM_RESERVE, PAGE_NOACCESS))
continue; /* oh well */
}
offsets[SH_TOTAL_SIZE] += delta;
#if 0
if (!child_proc_info && wincap.needs_memory_protection ())
for (DWORD s = 0x950000; s <= 0xa40000; s += 0x1000)
VirtualAlloc ((void *) s, 4, MEM_RESERVE, PAGE_NOACCESS);
#endif
}
debug_printf ("name %s, shared %p (wanted %p), h %p", name, shared, addr, shared_h);
return shared;
}
void
user_shared_initialize (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);
DWORD sversion = (DWORD) InterlockedExchange ((LONG *) &user_shared->version, USER_VERSION_MAGIC);
/* Initialize the Cygwin per-user shared, if necessary */
if (!sversion)
{
debug_printf ("initializing user shared");
user_shared->mountinfo.init (); /* Initialize the mount table. */
user_shared->delqueue.init (); /* Initialize the queue of deleted files. */
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));
}
}
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 ();
if (!sversion)
{
tty.init (); /* Initialize tty table. */
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 = SH_CYGWIN_SHARED;
cygwin_shared = (shared_info *) open_shared ("shared",
CYGWIN_VERSION_SHARED_DATA,
cygheap->shared_h,
sizeof (*cygwin_shared),
sh_cygwin_shared);
cygwin_shared->initialize ();
ProtectHandleINH (cygheap->shared_h);
user_shared_initialize (false);
mtinfo_init ();
}
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;
debug_printf ("fixed heap size is %u", heap_chunk);
}
return heap_chunk;
}