newlib/winsup/cygwin/pinfo.cc

411 lines
9.0 KiB
C++

/* pinfo.cc: process table support
Copyright 1996, 1997, 1998, 2000, 2001, 2002 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 <errno.h>
#include <limits.h>
#include "security.h"
#include "fhandler.h"
#include "path.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"
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);
if (!DuplicateHandle (hMainProc, hMainProc, hMainProc, &hexec_proc, 0,
TRUE, DUPLICATE_SAME_ACCESS))
{
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, 1, 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));
strace.hello ();
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;
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);
}
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;
}
int createit = flag & (PID_IN_USE | PID_EXECED);
for (int i = 0; i < 10; i++)
{
int created;
char mapname[MAX_PATH];
__small_sprintf (mapname, "cygpid.%x", 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 (FILE_MAP_READ | FILE_MAP_WRITE, FALSE, mapname);
created = 0;
}
else
{
h = CreateFileMapping (INVALID_HANDLE_VALUE, &sec_all_nih,
PAGE_READWRITE, 0, mapsize, mapname);
created = h && GetLastError () != ERROR_ALREADY_EXISTS;
}
if (!h)
{
if (createit)
__seterrno ();
procinfo = NULL;
return;
}
procinfo = (_pinfo *) MapViewOfFile (h, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, 0);
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))
{
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::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));
if (winpid)
/* nothing to do */;
else if (!pinfolist[nelem])
return;
else
/* 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;
}
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;
}
void
winpids::init (bool winpid)
{
npids = (this->*enum_processes) (winpid);
if (pidlist)
pidlist[npids] = 0;
}
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);
}
}