newlib/winsup/cygwin/pinfo.cc

803 lines
18 KiB
C++

/* pinfo.cc: process table support
Copyright 1996, 1997, 1998, 2000, 2001, 2002, 2003 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 <stdlib.h>
#include <time.h>
#include <limits.h>
#include <stdarg.h>
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygerrno.h"
#include "sigproc.h"
#include "pinfo.h"
#include "cygwin_version.h"
#include "perprocess.h"
#include "environ.h"
#include <assert.h>
#include <ntdef.h>
#include "ntdll.h"
#include "cygthread.h"
#include "shared_info.h"
#include "cygheap.h"
#include "fhandler.h"
static char NO_COPY pinfo_dummy[sizeof (_pinfo)] = {0};
pinfo NO_COPY myself ((_pinfo *)&pinfo_dummy); // Avoid myself != NULL checks
HANDLE hexec_proc;
void __stdcall
pinfo_fixup_after_fork ()
{
if (hexec_proc)
CloseHandle (hexec_proc);
/* Keeps the cygpid from being reused. No rights required */
if (!DuplicateHandle (hMainProc, hMainProc, hMainProc, &hexec_proc, 0,
TRUE, 0))
{
system_printf ("couldn't save current process handle %p, %E", hMainProc);
hexec_proc = NULL;
}
}
/* Initialize the process table.
This is done once when the dll is first loaded. */
void __stdcall
set_myself (pid_t pid, HANDLE h)
{
DWORD winpid = GetCurrentProcessId ();
if (pid == 1)
pid = cygwin_pid (winpid);
myself.init (pid, PID_IN_USE | PID_MYSELF, h);
myself->dwProcessId = winpid;
myself->process_state |= PID_IN_USE;
myself->start_time = time (NULL); /* Register our starting time. */
(void) GetModuleFileName (NULL, myself->progname, sizeof (myself->progname));
if (!strace.active)
strace.hello ();
InitializeCriticalSection (&myself->lock);
return;
}
/* Initialize the process table entry for the current task.
This is not called for forked tasks, only execed ones. */
void __stdcall
pinfo_init (char **envp, int envc)
{
if (envp)
{
environ_init (envp, envc);
/* spawn has already set up a pid structure for us so we'll use that */
myself->process_state |= PID_CYGPARENT;
}
else
{
/* Invent our own pid. */
set_myself (1);
myself->ppid = 1;
myself->pgid = myself->sid = myself->pid;
myself->ctty = -1;
myself->uid = ILLEGAL_UID;
myself->gid = UNKNOWN_GID;
environ_init (NULL, 0); /* call after myself has been set up */
}
debug_printf ("pid %d, pgid %d", myself->pid, myself->pgid);
}
void
_pinfo::exit (UINT n, bool norecord)
{
if (this)
{
if (!norecord)
process_state = PID_EXITED;
/* FIXME: There is a potential race between an execed process and its
parent here. I hated to add a mutex just for this, though. */
struct rusage r;
fill_rusage (&r, hMainProc);
add_rusage (&rusage_self, &r);
}
cygthread::terminate ();
sigproc_printf ("Calling ExitProcess %d", n);
ExitProcess (n);
}
void
pinfo::init (pid_t n, DWORD flag, HANDLE in_h)
{
if (myself && n == myself->pid)
{
procinfo = myself;
destroy = 0;
h = NULL;
return;
}
void *mapaddr;
if (!(flag & PID_MYSELF))
mapaddr = NULL;
else
{
flag &= ~PID_MYSELF;
HANDLE hdummy;
mapaddr = open_shared (NULL, 0, hdummy, 0, SH_MYSELF);
}
int createit = flag & (PID_IN_USE | PID_EXECED);
DWORD access = FILE_MAP_READ
| (flag & (PID_IN_USE | PID_EXECED | PID_MAP_RW) ? FILE_MAP_WRITE : 0);
for (int i = 0; i < 10; i++)
{
int created;
char mapname[CYG_MAX_PATH]; /* XXX Not a path */
shared_name (mapname, "cygpid", n);
int mapsize;
if (flag & PID_EXECED)
mapsize = PINFO_REDIR_SIZE;
else
mapsize = sizeof (_pinfo);
if (in_h)
{
h = in_h;
created = 0;
}
else if (!createit)
{
h = OpenFileMappingA (access, FALSE, mapname);
created = 0;
}
else
{
char sa_buf[1024];
PSECURITY_ATTRIBUTES sec_attribs =
sec_user_nih (sa_buf, cygheap->user.sid(), well_known_world_sid,
FILE_MAP_READ);
h = CreateFileMapping (INVALID_HANDLE_VALUE, sec_attribs,
PAGE_READWRITE, 0, mapsize, mapname);
created = h && GetLastError () != ERROR_ALREADY_EXISTS;
}
if (!h)
{
if (createit)
__seterrno ();
procinfo = NULL;
return;
}
procinfo = (_pinfo *) MapViewOfFileEx (h, access, 0, 0, 0, mapaddr);
ProtectHandle1 (h, pinfo_shared_handle);
if ((procinfo->process_state & PID_INITIALIZING) && (flag & PID_NOREDIR)
&& cygwin_pid (procinfo->dwProcessId) != procinfo->pid)
{
release ();
set_errno (ENOENT);
return;
}
if (procinfo->process_state & PID_EXECED)
{
assert (!i);
pid_t realpid = procinfo->pid;
debug_printf ("execed process windows pid %d, cygwin pid %d", n, realpid);
if (realpid == n)
api_fatal ("retrieval of execed process info for pid %d failed due to recursion.", n);
n = realpid;
release ();
if (flag & PID_ALLPIDS)
{
set_errno (ENOENT);
break;
}
continue;
}
/* In certain rare, pathological cases, it is possible for the shared
memory region to exist for a while after a process has exited. This
should only be a brief occurrence, so rather than introduce some kind
of locking mechanism, just loop. FIXME: I'm sure I'll regret doing it
this way at some point. */
if (i < 9 && !created && createit && (procinfo->process_state & PID_EXITED))
{
low_priority_sleep (5);
release ();
continue;
}
if (!created)
/* nothing */;
else if (!(flag & PID_EXECED))
procinfo->pid = n;
else
{
procinfo->process_state |= PID_IN_USE | PID_EXECED;
procinfo->pid = myself->pid;
}
break;
}
destroy = 1;
}
void
pinfo::set_acl()
{
char sa_buf[1024];
SECURITY_DESCRIPTOR sd;
sec_acl ((PACL) sa_buf, true, true, cygheap->user.sid (),
well_known_world_sid, FILE_MAP_READ);
if (!InitializeSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION))
debug_printf ("InitializeSecurityDescriptor %E");
else if (!SetSecurityDescriptorDacl (&sd, TRUE, (PACL) sa_buf, FALSE))
debug_printf ("SetSecurityDescriptorDacl %E");
else if (!SetKernelObjectSecurity (h, DACL_SECURITY_INFORMATION, &sd))
debug_printf ("SetKernelObjectSecurity %E");
}
void
_pinfo::set_ctty (tty_min *tc, int flags, fhandler_tty_slave *arch)
{
debug_printf ("checking if /dev/tty%d differs from input", ctty);
if ((ctty < 0 || ctty == tc->ntty) && !(flags & O_NOCTTY))
{
ctty = tc->ntty;
syscall_printf ("attached tty%d sid %d, pid %d, tty->pgid %d, tty->sid %d",
tc->ntty, sid, pid, pgid, tc->getsid ());
pinfo p (tc->getsid ());
if (sid == pid && (!p || p->pid == pid || !proc_exists (p)))
{
paranoid_printf ("resetting tty%d sid. Was %d, now %d. pgid was %d, now %d.",
tc->ntty, tc->getsid (), sid, tc->getpgid (), pgid);
/* We are the session leader */
tc->setsid (sid);
tc->setpgid (pgid);
}
else
sid = tc->getsid ();
if (tc->getpgid () == 0)
tc->setpgid (pgid);
if (cygheap->ctty != arch)
{
debug_printf ("cygheap->ctty %p, arch %p", cygheap->ctty, arch);
if (!cygheap->ctty)
syscall_printf ("ctty NULL");
else
{
syscall_printf ("ctty %p, usecount %d", cygheap->ctty,
cygheap->ctty->usecount);
cygheap->ctty->close ();
}
cygheap->ctty = arch;
if (arch)
{
arch->usecount++;
cygheap->open_fhs++;
report_tty_counts (cygheap->ctty, "ctty", "incremented ", "");
}
}
}
}
bool
_pinfo::alive ()
{
HANDLE h = OpenProcess (PROCESS_QUERY_INFORMATION, false, dwProcessId);
if (h)
CloseHandle (h);
return !!h;
}
extern char **__argv;
void
_pinfo::commune_recv ()
{
DWORD nr;
DWORD code;
HANDLE hp;
HANDLE __fromthem = NULL;
HANDLE __tothem = NULL;
hp = OpenProcess (PROCESS_DUP_HANDLE, false, dwProcessId);
if (!hp)
{
sigproc_printf ("couldn't open handle for pid %d(%u)", pid, dwProcessId);
hello_pid = -1;
return;
}
if (!DuplicateHandle (hp, fromthem, hMainProc, &__fromthem, 0, false, DUPLICATE_SAME_ACCESS))
{
sigproc_printf ("couldn't duplicate fromthem, %E");
CloseHandle (hp);
hello_pid = -1;
return;
}
if (!DuplicateHandle (hp, tothem, hMainProc, &__tothem, 0, false, DUPLICATE_SAME_ACCESS))
{
sigproc_printf ("couldn't duplicate tothem, %E");
CloseHandle (__fromthem);
CloseHandle (hp);
hello_pid = -1;
return;
}
CloseHandle (hp);
hello_pid = 0;
if (!ReadFile (__fromthem, &code, sizeof code, &nr, NULL) || nr != sizeof code)
{
/* __seterrno ();*/ // this is run from the signal thread, so don't set errno
goto out;
}
switch (code)
{
case PICOM_CMDLINE:
{
unsigned n = 1;
CloseHandle (__fromthem); __fromthem = NULL;
extern int __argc_safe;
const char *argv[__argc_safe + 1];
for (int i = 0; i < __argc_safe; i++)
{
if (IsBadStringPtr (__argv[i], INT32_MAX))
argv[i] = "";
else
argv[i] = __argv[i];
n += strlen (argv[i]) + 1;
}
argv[__argc_safe] = NULL;
if (!WriteFile (__tothem, &n, sizeof n, &nr, NULL))
{
/*__seterrno ();*/ // this is run from the signal thread, so don't set errno
sigproc_printf ("WriteFile sizeof argv failed, %E");
}
else
for (const char **a = argv; *a; a++)
if (!WriteFile (__tothem, *a, strlen (*a) + 1, &nr, NULL))
{
sigproc_printf ("WriteFile arg %d failed, %E", a - argv);
break;
}
if (!WriteFile (__tothem, "", 1, &nr, NULL))
{
sigproc_printf ("WriteFile null failed, %E");
break;
}
break;
}
case PICOM_FIFO:
{
int formic;
if (!ReadFile (__fromthem, &formic, sizeof formic, &nr, NULL)
|| nr != sizeof formic)
{
/* __seterrno ();*/ // this is run from the signal thread, so don't set errno
goto out;
}
fhandler_fifo *fh = cygheap->fdtab.find_fifo ((ATOM) formic);
HANDLE it[] = {(fh->get_handle ()), (fh->get_output_handle ())};
if (!WriteFile (__tothem, it, sizeof (it), &nr, NULL))
{
/*__seterrno ();*/ // this is run from the signal thread, so don't set errno
sigproc_printf ("WriteFile read handle failed, %E");
}
(void) ReadFile (__fromthem, &nr, sizeof (nr), &nr, NULL);
break;
}
}
out:
if (__fromthem)
CloseHandle (__fromthem);
if (__tothem)
CloseHandle (__tothem);
}
#define PIPEBUFSIZE (16 * sizeof (DWORD))
commune_result
_pinfo::commune_send (DWORD code, ...)
{
HANDLE fromthem = NULL, tome = NULL;
HANDLE fromme = NULL, tothem = NULL;
DWORD nr;
commune_result res;
va_list args;
va_start (args, code);
res.s = NULL;
res.n = 0;
if (!this || !pid)
{
set_errno (ESRCH);
goto err;
}
if (!CreatePipe (&fromthem, &tome, &sec_all_nih, PIPEBUFSIZE))
{
sigproc_printf ("first CreatePipe failed, %E");
__seterrno ();
goto err;
}
if (!CreatePipe (&fromme, &tothem, &sec_all_nih, PIPEBUFSIZE))
{
sigproc_printf ("first CreatePipe failed, %E");
__seterrno ();
goto err;
}
EnterCriticalSection (&myself->lock);
myself->tothem = tome;
myself->fromthem = fromme;
myself->hello_pid = pid;
if (!WriteFile (tothem, &code, sizeof code, &nr, NULL) || nr != sizeof code)
{
__seterrno ();
goto err;
}
switch (code)
{
case PICOM_FIFO:
{
int formic = va_arg (args, int);
if (!WriteFile (tothem, &formic, sizeof formic, &nr, NULL) || nr != sizeof formic)
{
__seterrno ();
goto err;
}
break;
}
}
if (sig_send (this, __SIGCOMMUNE))
goto err;
/* FIXME: Need something better than an busy loop here */
bool isalive;
for (int i = 0; (isalive = alive ()) && (i < 10000); i++)
if (myself->hello_pid <= 0)
break;
else
low_priority_sleep (0);
CloseHandle (tome);
tome = NULL;
CloseHandle (fromme);
fromme = NULL;
if (!isalive)
{
set_errno (ESRCH);
goto err;
}
if (myself->hello_pid < 0)
{
set_errno (ENOSYS);
goto err;
}
size_t n;
switch (code)
{
case PICOM_CMDLINE:
if (!ReadFile (fromthem, &n, sizeof n, &nr, NULL) || nr != sizeof n)
{
__seterrno ();
goto err;
}
res.s = (char *) malloc (n);
char *p;
for (p = res.s; ReadFile (fromthem, p, n, &nr, NULL); p += nr)
continue;
if ((unsigned) (p - res.s) != n)
{
__seterrno ();
goto err;
}
res.n = n;
break;
case PICOM_FIFO:
{
DWORD x = ReadFile (fromthem, res.handles, sizeof (res.handles), &nr, NULL);
WriteFile (tothem, &x, sizeof (x), &x, NULL);
if (!x)
goto err;
if (nr != sizeof (res.handles))
{
set_errno (EPIPE);
goto err;
}
break;
}
}
CloseHandle (tothem);
CloseHandle (fromthem);
goto out;
err:
if (tome)
CloseHandle (tome);
if (fromthem)
CloseHandle (fromthem);
if (tothem)
CloseHandle (tothem);
if (fromme)
CloseHandle (fromme);
memset (&res, 0, sizeof (res));
out:
myself->hello_pid = 0;
LeaveCriticalSection (&myself->lock);
return res;
}
char *
_pinfo::cmdline (size_t& n)
{
char *s;
if (!this || !pid)
return NULL;
if (pid != myself->pid)
{
commune_result cr = commune_send (PICOM_CMDLINE);
s = cr.s;
n = cr.n;
}
else
{
n = 1;
for (char **a = __argv; *a; a++)
n += strlen (*a) + 1;
char *p;
p = s = (char *) malloc (n);
for (char **a = __argv; *a; a++)
{
strcpy (p, *a);
p = strchr (p, '\0') + 1;
}
*p = '\0';
}
return s;
}
void
pinfo::release ()
{
if (h)
{
#ifdef DEBUGGING
if (((DWORD) procinfo & 0x77000000) == 0x61000000)
try_to_debug ();
#endif
UnmapViewOfFile (procinfo);
procinfo = NULL;
ForceCloseHandle1 (h, pinfo_shared_handle);
h = NULL;
}
}
/* DOCTOOL-START
<sect1 id="func-cygwin-winpid-to-pid">
<title>cygwin_winpid_to_pid</title>
<funcsynopsis>
<funcdef>extern "C" pid_t
<function>cygwin_winpid_to_pid</function>
</funcdef>
<paramdef>int <parameter>winpid</parameter></paramdef>
</funcsynopsis>
<para>Given a windows pid, converts to the corresponding Cygwin
pid, if any. Returns -1 if windows pid does not correspond to
a cygwin pid.</para>
<example>
<title>Example use of cygwin_winpid_to_pid</title>
<programlisting>
extern "C" cygwin_winpid_to_pid (int winpid);
pid_t mypid;
mypid = cygwin_winpid_to_pid (windows_pid);
</programlisting>
</example>
</sect1>
DOCTOOL-END */
extern "C" pid_t
cygwin_winpid_to_pid (int winpid)
{
pinfo p (cygwin_pid (winpid));
if (p)
return p->pid;
set_errno (ESRCH);
return (pid_t) -1;
}
#include <tlhelp32.h>
#define slop_pidlist 200
#define size_pidlist(i) (sizeof (pidlist[0]) * ((i) + 1))
#define size_pinfolist(i) (sizeof (pinfolist[0]) * ((i) + 1))
inline void
winpids::add (DWORD& nelem, bool winpid, DWORD pid)
{
pid_t cygpid = cygwin_pid (pid);
if (nelem >= npidlist)
{
npidlist += slop_pidlist;
pidlist = (DWORD *) realloc (pidlist, size_pidlist (npidlist + 1));
pinfolist = (pinfo *) realloc (pinfolist, size_pinfolist (npidlist + 1));
}
pinfolist[nelem].init (cygpid, PID_NOREDIR | (winpid ? PID_ALLPIDS : 0)
| pinfo_access);
if (winpid)
goto out;
if (!pinfolist[nelem])
{
if (!pinfo_access)
return;
pinfolist[nelem].init (cygpid, PID_NOREDIR | (winpid ? PID_ALLPIDS : 0));
if (!pinfolist[nelem])
return;
}
/* Scan list of previously recorded pids to make sure that this pid hasn't
shown up before. This can happen when a process execs. */
for (unsigned i = 0; i < nelem; i++)
if (pinfolist[i]->pid == pinfolist[nelem]->pid)
{
if ((_pinfo *) pinfolist[nelem] != (_pinfo *) myself)
pinfolist[nelem].release ();
return;
}
out:
pidlist[nelem++] = pid;
}
DWORD
winpids::enumNT (bool winpid)
{
static DWORD szprocs;
static SYSTEM_PROCESSES *procs;
DWORD nelem = 0;
if (!szprocs)
procs = (SYSTEM_PROCESSES *) malloc (sizeof (*procs) + (szprocs = 200 * sizeof (*procs)));
NTSTATUS res;
for (;;)
{
res = NtQuerySystemInformation (SystemProcessesAndThreadsInformation,
procs, szprocs, NULL);
if (res == 0)
break;
if (res == STATUS_INFO_LENGTH_MISMATCH)
procs = (SYSTEM_PROCESSES *) realloc (procs, szprocs += 200 * sizeof (*procs));
else
{
system_printf ("error %p reading system process information", res);
return 0;
}
}
SYSTEM_PROCESSES *px = procs;
for (;;)
{
if (px->ProcessId)
add (nelem, winpid, px->ProcessId);
if (!px->NextEntryDelta)
break;
px = (SYSTEM_PROCESSES *) ((char *) px + px->NextEntryDelta);
}
return nelem;
}
DWORD
winpids::enum9x (bool winpid)
{
DWORD nelem = 0;
HANDLE h = CreateToolhelp32Snapshot (TH32CS_SNAPPROCESS, 0);
if (!h)
{
system_printf ("Couldn't create process snapshot, %E");
return 0;
}
PROCESSENTRY32 proc;
proc.dwSize = sizeof (proc);
if (Process32First (h, &proc))
do
{
if (proc.th32ProcessID)
add (nelem, winpid, proc.th32ProcessID);
}
while (Process32Next (h, &proc));
CloseHandle (h);
return nelem;
}
NO_COPY CRITICAL_SECTION winpids::cs;
void
winpids::set (bool winpid)
{
EnterCriticalSection (&cs);
npids = (this->*enum_processes) (winpid);
if (pidlist)
pidlist[npids] = 0;
LeaveCriticalSection (&cs);
}
void
winpids::init ()
{
InitializeCriticalSection (&cs);
}
DWORD
winpids::enum_init (bool winpid)
{
if (wincap.is_winnt ())
enum_processes = &winpids::enumNT;
else
enum_processes = &winpids::enum9x;
return (this->*enum_processes) (winpid);
}
void
winpids::release ()
{
for (unsigned i = 0; i < npids; i++)
if (pinfolist[i] && (_pinfo *) pinfolist[i] != (_pinfo *) myself)
pinfolist[i].release ();
}
winpids::~winpids ()
{
if (npidlist)
{
release ();
free (pidlist);
free (pinfolist);
}
}