newlib-cygwin/winsup/cygwin/cygheap.cc

438 lines
11 KiB
C++

/* cygheap.cc: Cygwin heap manager.
Copyright 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 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 <string.h>
#include <assert.h>
#include <stdlib.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "child_info.h"
#include "heap.h"
#include "sync.h"
#include "sigproc.h"
#include "pinfo.h"
#include <unistd.h>
init_cygheap NO_COPY *cygheap;
void NO_COPY *cygheap_max;
extern "C" char _cygheap_mid[] __attribute__((section(".cygheap")));
extern "C" char _cygheap_end[];
static NO_COPY muto cygheap_protect;
struct cygheap_entry
{
int type;
struct cygheap_entry *next;
char data[0];
};
#define NBUCKETS (sizeof (cygheap->buckets) / sizeof (cygheap->buckets[0]))
#define N0 ((_cmalloc_entry *) NULL)
#define to_cmalloc(s) ((_cmalloc_entry *) (((char *) (s)) - (unsigned) (N0->data)))
#define CFMAP_OPTIONS (SEC_RESERVE | PAGE_READWRITE)
#define MVMAP_OPTIONS (FILE_MAP_WRITE)
extern "C" {
static void __stdcall _cfree (void *) __attribute__((regparm(1)));
static void *__stdcall _csbrk (int);
}
/* Called by fork or spawn to reallocate cygwin heap */
void __stdcall
cygheap_fixup_in_child (bool execed)
{
cygheap_max = child_proc_info->cygheap;
cygheap = (init_cygheap *) cygheap_max;
_csbrk ((char *) child_proc_info->cygheap_max - (char *) cygheap);
child_copy (child_proc_info->parent, false, "cygheap", cygheap, cygheap_max, NULL);
cygheap_init ();
debug_fixup_after_fork_exec ();
if (execed)
{
cygheap->hooks.next = NULL;
cygheap->user_heap.base = NULL; /* We can allocate the heap anywhere */
/* Walk the allocated memory chain looking for orphaned memory from
previous execs */
for (_cmalloc_entry *rvc = cygheap->chain; rvc; rvc = rvc->prev)
{
cygheap_entry *ce = (cygheap_entry *) rvc->data;
if (!rvc->ptr || rvc->b >= NBUCKETS || ce->type <= HEAP_1_START)
continue;
else if (ce->type < HEAP_1_MAX)
ce->type += HEAP_1_MAX; /* Mark for freeing after next exec */
else
_cfree (ce); /* Marked by parent for freeing in child */
}
}
}
int
init_cygheap::manage_console_count (const char *something, int amount, bool avoid_freeing_console)
{
if (console_count == 0 && amount > 0)
init_console_handler (true);
console_count += amount;
debug_printf ("%s: console_count %d, amount %d, %s, avoid_freeing_console %d",
something, console_count, amount, myctty (), avoid_freeing_console);
if (!avoid_freeing_console && amount <= 0 && !console_count && myself->ctty == -1)
{
BOOL res = FreeConsole ();
debug_printf ("freed console, res %d", res);
init_console_handler (false);
}
return console_count;
}
void
init_cygheap::close_ctty ()
{
debug_printf ("closing cygheap->ctty %p", cygheap->ctty);
cygheap->ctty->close ();
cygheap->ctty = NULL;
}
#define nextpage(x) ((char *) (((DWORD) ((char *) x + granmask)) & ~granmask))
#define allocsize(x) ((DWORD) nextpage (x))
#ifdef DEBUGGING
#define somekinda_printf debug_printf
#else
#define somekinda_printf malloc_printf
#endif
static void *__stdcall
_csbrk (int sbs)
{
void *prebrk = cygheap_max;
size_t granmask = getpagesize () - 1;
char *newbase = nextpage (prebrk);
cygheap_max = (char *) cygheap_max + sbs;
if (!sbs || (newbase >= cygheap_max) || (cygheap_max <= _cygheap_end))
/* nothing to do */;
else
{
if (prebrk <= _cygheap_end)
newbase = _cygheap_end;
DWORD adjsbs = allocsize ((char *) cygheap_max - newbase);
if (!VirtualAlloc (newbase, adjsbs, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE))
{
MEMORY_BASIC_INFORMATION m;
if (!VirtualQuery (newbase, &m, sizeof m))
system_printf ("couldn't get memory info, %E");
somekinda_printf ("Couldn't reserve/commit %d bytes of space for cygwin's heap, %E",
adjsbs);
somekinda_printf ("AllocationBase %p, BaseAddress %p, RegionSize %p, State %p\n",
m.AllocationBase, m.BaseAddress, m.RegionSize, m.State);
__seterrno ();
cygheap_max = (char *) cygheap_max - sbs;
return NULL;
}
}
return prebrk;
}
extern "C" void __stdcall
cygheap_init ()
{
cygheap_protect.init ("cygheap_protect");
if (!cygheap)
{
cygheap = (init_cygheap *) memset (_cygheap_start, 0, _cygheap_mid - _cygheap_start);
cygheap_max = cygheap;
_csbrk (sizeof (*cygheap));
}
if (!cygheap->fdtab)
cygheap->fdtab.init ();
if (!cygheap->sigs)
sigalloc ();
/* TODO: This is plain wrong. There's a difference between global shared
memory and every other global object. It's still allowed to
create any global object from a process not having the
SE_CREATE_GLOBAL_NAME privilege. It's only disallowed to create
global shared memory objects when not running in session 0 or
when not having the privilege.
The end result should look like this:
- All objects shared between multiple processes except shared
memory should always be created as global objects.
- Shared memory only needed locally should stick to being session
local.
- Every process should always try to create resp. open shared
memory as global.
- Only if that fails it should try to create the shared memory
as local shared memory, or ...
- ... the MS suggested workaround is to create a file backed shared
memory if a process has not the privilege to create global shared
memory.
However, this has to be planned carefully, especially given that
every single process creates its own (resp. the child's) shared
memory area with the process specific information. */
if (!cygheap->shared_prefix)
cygheap->shared_prefix = cstrdup (
wincap.has_terminal_services ()
&& (set_privilege (hProcToken, SE_CREATE_GLOBAL_PRIV, true) >= 0
|| GetLastError () == ERROR_NO_SUCH_PRIVILEGE)
? "Global\\" : "");
}
/* Copyright (C) 1997, 2000 DJ Delorie */
static void *_cmalloc (unsigned size) __attribute ((regparm(1)));
static void *__stdcall _crealloc (void *ptr, unsigned size) __attribute ((regparm(2)));
static void *__stdcall
_cmalloc (unsigned size)
{
_cmalloc_entry *rvc;
unsigned b, sz;
/* Calculate "bit bucket" and size as a power of two. */
for (b = 3, sz = 8; sz && sz < size; b++, sz <<= 1)
continue;
cygheap_protect.acquire ();
if (cygheap->buckets[b])
{
rvc = (_cmalloc_entry *) cygheap->buckets[b];
cygheap->buckets[b] = rvc->ptr;
rvc->b = b;
}
else
{
rvc = (_cmalloc_entry *) _csbrk (sz + sizeof (_cmalloc_entry));
if (!rvc)
{
cygheap_protect.release ();
return NULL;
}
rvc->b = b;
rvc->prev = cygheap->chain;
cygheap->chain = rvc;
}
cygheap_protect.release ();
return rvc->data;
}
static void __stdcall
_cfree (void *ptr)
{
cygheap_protect.acquire ();
_cmalloc_entry *rvc = to_cmalloc (ptr);
DWORD b = rvc->b;
rvc->ptr = cygheap->buckets[b];
cygheap->buckets[b] = (char *) rvc;
cygheap_protect.release ();
}
static void *__stdcall
_crealloc (void *ptr, unsigned size)
{
void *newptr;
if (ptr == NULL)
newptr = _cmalloc (size);
else
{
unsigned oldsize = 1 << to_cmalloc (ptr)->b;
if (size <= oldsize)
return ptr;
newptr = _cmalloc (size);
memcpy (newptr, ptr, oldsize);
_cfree (ptr);
}
return newptr;
}
/* End Copyright (C) 1997 DJ Delorie */
#define sizeof_cygheap(n) ((n) + sizeof (cygheap_entry))
#define N ((cygheap_entry *) NULL)
#define tocygheap(s) ((cygheap_entry *) (((char *) (s)) - (int) (N->data)))
inline static void *
creturn (cygheap_types x, cygheap_entry * c, unsigned len)
{
if (!c)
{
set_errno (ENOMEM);
return NULL;
}
c->type = x;
char *cend = ((char *) c + sizeof (*c) + len);
if (cygheap_max < cend)
cygheap_max = cend;
MALLOC_CHECK;
return (void *) c->data;
}
extern "C" void *__stdcall
cmalloc (cygheap_types x, DWORD n)
{
cygheap_entry *c;
MALLOC_CHECK;
c = (cygheap_entry *) _cmalloc (sizeof_cygheap (n));
if (!c)
{
#ifdef DEBUGGING
system_printf ("cmalloc returned NULL");
try_to_debug ();
#endif
}
return creturn (x, c, n);
}
extern "C" void *__stdcall
crealloc (void *s, DWORD n)
{
MALLOC_CHECK;
if (s == NULL)
return cmalloc (HEAP_STR, n); // kludge
assert (!inheap (s));
cygheap_entry *c = tocygheap (s);
cygheap_types t = (cygheap_types) c->type;
c = (cygheap_entry *) _crealloc (c, sizeof_cygheap (n));
#ifdef DEBUGGING
if (!c)
system_printf ("crealloc returned NULL");
#endif
return creturn (t, c, n);
}
extern "C" void __stdcall
cfree (void *s)
{
assert (!inheap (s));
_cfree (tocygheap (s));
MALLOC_CHECK;
}
extern "C" void __stdcall
cfree_and_set (char *&s, char *what)
{
if (s && s != almost_null)
cfree (s);
s = what;
}
extern "C" void *__stdcall
ccalloc (cygheap_types x, DWORD n, DWORD size)
{
cygheap_entry *c;
MALLOC_CHECK;
n *= size;
c = (cygheap_entry *) _cmalloc (sizeof_cygheap (n));
if (c)
memset (c->data, 0, n);
#ifdef DEBUGGING
if (!c)
system_printf ("ccalloc returned NULL");
#endif
return creturn (x, c, n);
}
extern "C" char *__stdcall
cstrdup (const char *s)
{
MALLOC_CHECK;
char *p = (char *) cmalloc (HEAP_STR, strlen (s) + 1);
if (!p)
return NULL;
strcpy (p, s);
MALLOC_CHECK;
return p;
}
extern "C" char *__stdcall
cstrdup1 (const char *s)
{
MALLOC_CHECK;
char *p = (char *) cmalloc (HEAP_1_STR, strlen (s) + 1);
if (!p)
return NULL;
strcpy (p, s);
MALLOC_CHECK;
return p;
}
void
cygheap_root::set (const char *posix, const char *native)
{
if (*posix == '/' && posix[1] == '\0')
{
if (m)
{
cfree (m);
m = NULL;
}
return;
}
if (!m)
m = (struct cygheap_root_mount_info *) ccalloc (HEAP_MOUNT, 1, sizeof (*m));
strcpy (m->posix_path, posix);
m->posix_pathlen = strlen (posix);
if (m->posix_pathlen >= 1 && m->posix_path[m->posix_pathlen - 1] == '/')
m->posix_path[--m->posix_pathlen] = '\0';
strcpy (m->native_path, native);
m->native_pathlen = strlen (native);
if (m->native_pathlen >= 1 && m->native_path[m->native_pathlen - 1] == '\\')
m->native_path[--m->native_pathlen] = '\0';
}
cygheap_user::~cygheap_user ()
{
#if 0
if (pname)
cfree (pname);
if (plogsrv)
cfree (plogsrv - 2);
if (pdomain)
cfree (pdomain);
if (psid)
cfree (psid);
#endif
}
void
cygheap_user::set_name (const char *new_name)
{
bool allocated = !!pname;
if (allocated)
{
if (strcasematch (new_name, pname))
return;
cfree (pname);
}
pname = cstrdup (new_name ? new_name : "");
if (!allocated)
return; /* Initializing. Don't bother with other stuff. */
cfree_and_set (homedrive);
cfree_and_set (homepath);
cfree_and_set (plogsrv);
cfree_and_set (pdomain);
cfree_and_set (pwinname);
}