535 lines
13 KiB
C++
535 lines
13 KiB
C++
/* pipe.cc: pipe for Cygwin.
|
|
|
|
Copyright 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
|
|
2008 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. */
|
|
|
|
/* FIXME: Should this really be fhandler_pipe.cc? */
|
|
|
|
#include "winsup.h"
|
|
#include <stdlib.h>
|
|
#include <sys/socket.h>
|
|
#include "cygerrno.h"
|
|
#include "security.h"
|
|
#include "path.h"
|
|
#include "fhandler.h"
|
|
#include "dtable.h"
|
|
#include "cygheap.h"
|
|
#include "pinfo.h"
|
|
|
|
fhandler_pipe::fhandler_pipe ()
|
|
: fhandler_base (), popen_pid (0)
|
|
{
|
|
get_overlapped ()->hEvent = NULL;
|
|
need_fork_fixup (true);
|
|
}
|
|
|
|
struct pipesync
|
|
{
|
|
bool reader;
|
|
HANDLE ev, non_cygwin_h, ret_handle;
|
|
pipesync(HANDLE, DWORD);
|
|
int operator == (int x) const {return !!ev;}
|
|
static DWORD WINAPI handler (LPVOID *);
|
|
};
|
|
|
|
inline bool
|
|
getov_result (HANDLE h, DWORD& nbytes, LPOVERLAPPED ov)
|
|
{
|
|
if (ov && (GetLastError () != ERROR_IO_PENDING
|
|
|| !GetOverlappedResult (h, ov, &nbytes, true)))
|
|
{
|
|
__seterrno ();
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static DWORD WINAPI
|
|
pipe_handler (LPVOID in_ps)
|
|
{
|
|
pipesync ps = *(pipesync *) in_ps;
|
|
HANDLE h, in, out;
|
|
DWORD err = fhandler_pipe::create_selectable (&sec_none_nih, in, out, 0);
|
|
if (err)
|
|
{
|
|
SetLastError (err);
|
|
system_printf ("couldn't create a shadow pipe for non-cygwin pipe I/O, %E");
|
|
return 0;
|
|
}
|
|
h = ((pipesync *) in_ps)->ret_handle = ps.reader ? in : out;
|
|
SetHandleInformation (h, HANDLE_FLAG_INHERIT, HANDLE_FLAG_INHERIT);
|
|
SetEvent (ps.ev);
|
|
|
|
char buf[4096];
|
|
DWORD read_bytes, write_bytes;
|
|
HANDLE hread, hwrite, hclose;
|
|
OVERLAPPED ov, *rov, *wov;
|
|
memset (&ov, 0, sizeof (ov));
|
|
ov.hEvent = CreateEvent (&sec_none_nih, true, false, NULL);
|
|
if (ps.reader)
|
|
{
|
|
hread = ps.non_cygwin_h;
|
|
hclose = hwrite = out;
|
|
wov = &ov;
|
|
rov = NULL;
|
|
}
|
|
else
|
|
{
|
|
hclose = hread = in;
|
|
hwrite = ps.non_cygwin_h;
|
|
rov = &ov;
|
|
wov = NULL;
|
|
}
|
|
|
|
while (1)
|
|
{
|
|
ResetEvent (ov.hEvent);
|
|
BOOL res = ReadFile (hread, buf, 4096, &read_bytes, rov);
|
|
if (!res && !getov_result (hread, read_bytes, rov))
|
|
break;
|
|
if (!read_bytes)
|
|
break;
|
|
|
|
res = WriteFile (hwrite, buf, read_bytes, &write_bytes, wov);
|
|
if (!res && !getov_result (hwrite, write_bytes, wov))
|
|
break;
|
|
if (write_bytes != read_bytes)
|
|
break;
|
|
}
|
|
|
|
err = GetLastError ();
|
|
CloseHandle (ov.hEvent);
|
|
CloseHandle (hclose);
|
|
CloseHandle (ps.non_cygwin_h);
|
|
SetLastError (err);
|
|
return 0;
|
|
}
|
|
|
|
pipesync::pipesync (HANDLE f, DWORD is_reader):
|
|
reader (false), ret_handle (NULL)
|
|
{
|
|
ev = CreateEvent (&sec_none_nih, true, false, NULL);
|
|
if (!ev)
|
|
{
|
|
system_printf ("couldn't create synchronization event for non-cygwin pipe, %E");
|
|
goto out;
|
|
}
|
|
debug_printf ("created thread synchronization event %p", ev);
|
|
non_cygwin_h = f;
|
|
reader = !!is_reader;
|
|
ret_handle = NULL;
|
|
|
|
DWORD tid;
|
|
HANDLE ht = CreateThread (&sec_none_nih, 0, pipe_handler, this, 0, &tid);
|
|
|
|
if (!ht)
|
|
goto out;
|
|
CloseHandle (ht);
|
|
|
|
switch (WaitForSingleObject (ev, INFINITE))
|
|
{
|
|
case WAIT_OBJECT_0:
|
|
break;
|
|
default:
|
|
system_printf ("WFSO failed waiting for synchronization event for non-cygwin pipe, %E");
|
|
break;
|
|
}
|
|
|
|
out:
|
|
if (ev)
|
|
{
|
|
CloseHandle (ev);
|
|
ev = NULL;
|
|
}
|
|
return;
|
|
}
|
|
|
|
void
|
|
fhandler_pipe::init (HANDLE f, DWORD a, mode_t mode)
|
|
{
|
|
// FIXME: Have to clean this up someday
|
|
if (!*get_win32_name () && get_name ())
|
|
{
|
|
char *hold_normalized_name = (char *) alloca (strlen (get_name ()) + 1);
|
|
strcpy (hold_normalized_name, get_name ());
|
|
char *s, *d;
|
|
for (s = hold_normalized_name, d = (char *) get_win32_name (); *s; s++, d++)
|
|
if (*s == '/')
|
|
*d = '\\';
|
|
else
|
|
*d = *s;
|
|
*d = '\0';
|
|
set_name (hold_normalized_name);
|
|
}
|
|
|
|
bool opened_properly = a & FILE_CREATE_PIPE_INSTANCE;
|
|
a &= ~FILE_CREATE_PIPE_INSTANCE;
|
|
if (!opened_properly)
|
|
{
|
|
pipesync ps (f, a & GENERIC_READ);
|
|
f = ps.ret_handle;
|
|
}
|
|
|
|
fhandler_base::init (f, a, mode);
|
|
if (mode & O_NOINHERIT)
|
|
close_on_exec (true);
|
|
setup_overlapped ();
|
|
}
|
|
|
|
extern "C" int sscanf (const char *, const char *, ...);
|
|
|
|
int
|
|
fhandler_pipe::open (int flags, mode_t mode)
|
|
{
|
|
HANDLE proc, pipe_hdl, nio_hdl = NULL;
|
|
fhandler_pipe *fh = NULL;
|
|
size_t size;
|
|
int pid, rwflags = (flags & O_ACCMODE);
|
|
bool inh;
|
|
|
|
sscanf (get_name (), "/proc/%d/fd/pipe:[%d]", &pid, (int *) &pipe_hdl);
|
|
if (pid == myself->pid)
|
|
{
|
|
cygheap_fdenum cfd (true);
|
|
while (cfd.next () >= 0)
|
|
{
|
|
if (cfd->get_handle () != pipe_hdl)
|
|
continue;
|
|
if ((rwflags == O_RDONLY && !(cfd->get_access () & GENERIC_READ))
|
|
|| (rwflags == O_WRONLY && !(cfd->get_access () & GENERIC_WRITE)))
|
|
{
|
|
set_errno (EACCES);
|
|
return 0;
|
|
}
|
|
if (!cfd->dup (this))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
set_errno (ENOENT);
|
|
return 0;
|
|
}
|
|
|
|
pinfo p (pid);
|
|
if (!p)
|
|
{
|
|
set_errno (ESRCH);
|
|
return 0;
|
|
}
|
|
if (!(proc = OpenProcess (PROCESS_DUP_HANDLE, false, p->dwProcessId)))
|
|
{
|
|
__seterrno ();
|
|
return 0;
|
|
}
|
|
if (!(fh = p->pipe_fhandler (pipe_hdl, size)) || !size)
|
|
{
|
|
set_errno (ENOENT);
|
|
goto out;
|
|
}
|
|
/* Too bad, but Windows only allows the same access mode when dup'ing
|
|
the pipe. */
|
|
if ((rwflags == O_RDONLY && !(fh->get_access () & GENERIC_READ))
|
|
|| (rwflags == O_WRONLY && !(fh->get_access () & GENERIC_WRITE)))
|
|
{
|
|
set_errno (EACCES);
|
|
goto out;
|
|
}
|
|
inh = !(flags & O_NOINHERIT);
|
|
if (!DuplicateHandle (proc, pipe_hdl, hMainProc, &nio_hdl,
|
|
0, inh, DUPLICATE_SAME_ACCESS))
|
|
{
|
|
__seterrno ();
|
|
goto out;
|
|
}
|
|
init (nio_hdl, fh->get_access (), mode & O_TEXT ?: O_BINARY);
|
|
if (flags & O_NOINHERIT)
|
|
close_on_exec (true);
|
|
uninterruptible_io (fh->uninterruptible_io ());
|
|
cfree (fh);
|
|
CloseHandle (proc);
|
|
return 1;
|
|
out:
|
|
if (nio_hdl)
|
|
CloseHandle (nio_hdl);
|
|
if (fh)
|
|
free (fh);
|
|
if (proc)
|
|
CloseHandle (proc);
|
|
return 0;
|
|
}
|
|
|
|
_off64_t
|
|
fhandler_pipe::lseek (_off64_t offset, int whence)
|
|
{
|
|
debug_printf ("(%d, %d)", offset, whence);
|
|
set_errno (ESPIPE);
|
|
return -1;
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::fadvise (_off64_t offset, _off64_t length, int advice)
|
|
{
|
|
set_errno (ESPIPE);
|
|
return -1;
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::ftruncate (_off64_t length, bool allow_truncate)
|
|
{
|
|
set_errno (allow_truncate ? EINVAL : ESPIPE);
|
|
return -1;
|
|
}
|
|
|
|
char *
|
|
fhandler_pipe::get_proc_fd_name (char *buf)
|
|
{
|
|
__small_sprintf (buf, "pipe:[%d]", get_handle ());
|
|
return buf;
|
|
}
|
|
|
|
void __stdcall
|
|
fhandler_pipe::read (void *in_ptr, size_t& in_len)
|
|
{
|
|
return read_overlapped (in_ptr, in_len);
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::write (const void *ptr, size_t len)
|
|
{
|
|
return write_overlapped (ptr, len);
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::dup (fhandler_base *child)
|
|
{
|
|
fhandler_pipe *ftp = (fhandler_pipe *) child;
|
|
ftp->set_popen_pid (0);
|
|
|
|
int res;
|
|
if (get_handle () && fhandler_base::dup (child))
|
|
res = -1;
|
|
else
|
|
res = 0;
|
|
|
|
debug_printf ("res %d", res);
|
|
return res;
|
|
}
|
|
|
|
#define PIPE_INTRO "\\\\.\\pipe\\cygwin-"
|
|
|
|
/* Create a pipe, and return handles to the read and write ends,
|
|
just like CreatePipe, but ensure that the write end permits
|
|
FILE_READ_ATTRIBUTES access, on later versions of win32 where
|
|
this is supported. This access is needed by NtQueryInformationFile,
|
|
which is used to implement select and nonblocking writes.
|
|
Note that the return value is either 0 or GetLastError,
|
|
unlike CreatePipe, which returns a bool for success or failure. */
|
|
int
|
|
fhandler_pipe::create_selectable (LPSECURITY_ATTRIBUTES sa_ptr, HANDLE& r,
|
|
HANDLE& w, DWORD psize, const char *name)
|
|
{
|
|
/* Default to error. */
|
|
r = w = INVALID_HANDLE_VALUE;
|
|
|
|
/* Ensure that there is enough pipe buffer space for atomic writes. */
|
|
if (psize < PIPE_BUF)
|
|
psize = PIPE_BUF;
|
|
|
|
char pipename[MAX_PATH] = PIPE_INTRO;
|
|
/* FIXME: Eventually make ttys work with overlapped I/O. */
|
|
DWORD overlapped = name ? 0 : FILE_FLAG_OVERLAPPED;
|
|
|
|
/* Retry CreateNamedPipe as long as the pipe name is in use.
|
|
Retrying will probably never be necessary, but we want
|
|
to be as robust as possible. */
|
|
DWORD err;
|
|
do
|
|
{
|
|
static volatile ULONG pipe_unique_id;
|
|
if (!name)
|
|
__small_sprintf (pipename + strlen(PIPE_INTRO), "%p-%p", myself->pid,
|
|
InterlockedIncrement ((LONG *) &pipe_unique_id));
|
|
else
|
|
strcpy (pipename + strlen(PIPE_INTRO), name);
|
|
|
|
debug_printf ("CreateNamedPipe: name %s, size %lu", pipename, psize);
|
|
|
|
err = 0;
|
|
/* Use CreateNamedPipe instead of CreatePipe, because the latter
|
|
returns a write handle that does not permit FILE_READ_ATTRIBUTES
|
|
access, on versions of win32 earlier than WinXP SP2.
|
|
CreatePipe also stupidly creates a full duplex pipe, which is
|
|
a waste, since only a single direction is actually used.
|
|
It's important to only allow a single instance, to ensure that
|
|
the pipe was not created earlier by some other process, even if
|
|
the pid has been reused. We avoid FILE_FLAG_FIRST_PIPE_INSTANCE
|
|
because that is only available for Win2k SP2 and WinXP. */
|
|
r = CreateNamedPipe (pipename, PIPE_ACCESS_INBOUND | overlapped,
|
|
PIPE_TYPE_BYTE | PIPE_READMODE_BYTE, 1, psize,
|
|
psize, NMPWAIT_USE_DEFAULT_WAIT, sa_ptr);
|
|
|
|
/* Win 95 seems to return NULL instead of INVALID_HANDLE_VALUE */
|
|
if (r && r != INVALID_HANDLE_VALUE)
|
|
{
|
|
debug_printf ("pipe read handle %p", r);
|
|
break;
|
|
}
|
|
|
|
err = GetLastError ();
|
|
switch (err)
|
|
{
|
|
case ERROR_PIPE_BUSY:
|
|
/* The pipe is already open with compatible parameters.
|
|
Pick a new name and retry. */
|
|
debug_printf ("pipe busy, retrying");
|
|
break;
|
|
case ERROR_ACCESS_DENIED:
|
|
/* The pipe is already open with incompatible parameters.
|
|
Pick a new name and retry. */
|
|
debug_printf ("pipe access denied, retrying");
|
|
break;
|
|
default:
|
|
{
|
|
err = GetLastError ();
|
|
debug_printf ("CreatePipe failed, %E");
|
|
return err;
|
|
}
|
|
}
|
|
}
|
|
while (!name);
|
|
|
|
if (err)
|
|
return err;
|
|
|
|
debug_printf ("CreateFile: name %s", pipename);
|
|
|
|
/* Open the named pipe for writing.
|
|
Be sure to permit FILE_READ_ATTRIBUTES access. */
|
|
w = CreateFile (pipename, GENERIC_WRITE | FILE_READ_ATTRIBUTES, 0, sa_ptr,
|
|
OPEN_EXISTING, overlapped, 0);
|
|
|
|
if (!w || w == INVALID_HANDLE_VALUE)
|
|
{
|
|
/* Failure. */
|
|
DWORD err = GetLastError ();
|
|
debug_printf ("CreateFile failed, %E");
|
|
CloseHandle (r);
|
|
return err;
|
|
}
|
|
|
|
debug_printf ("pipe write handle %p", w);
|
|
|
|
/* Success. */
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::create (fhandler_pipe *fhs[2], unsigned psize, int mode)
|
|
{
|
|
HANDLE r, w;
|
|
SECURITY_ATTRIBUTES *sa = (mode & O_NOINHERIT) ? &sec_none_nih : &sec_none;
|
|
int res;
|
|
|
|
int ret = create_selectable (sa, r, w, psize);
|
|
if (ret)
|
|
{
|
|
__seterrno_from_win_error (ret);
|
|
res = -1;
|
|
}
|
|
else
|
|
{
|
|
fhs[0] = (fhandler_pipe *) build_fh_dev (*piper_dev);
|
|
fhs[1] = (fhandler_pipe *) build_fh_dev (*pipew_dev);
|
|
|
|
mode |= mode & O_TEXT ?: O_BINARY;
|
|
fhs[0]->init (r, FILE_CREATE_PIPE_INSTANCE | GENERIC_READ, mode);
|
|
fhs[1]->init (w, FILE_CREATE_PIPE_INSTANCE | GENERIC_WRITE, mode);
|
|
res = 0;
|
|
}
|
|
|
|
syscall_printf ("%d = pipe ([%p, %p], %d, %p)", res, fhs[0], fhs[1], psize, mode);
|
|
return res;
|
|
}
|
|
|
|
int
|
|
fhandler_pipe::ioctl (unsigned int cmd, void *p)
|
|
{
|
|
int n;
|
|
|
|
switch (cmd)
|
|
{
|
|
case FIONREAD:
|
|
if (get_device () == FH_PIPEW)
|
|
{
|
|
set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
if (!PeekNamedPipe (get_handle (), NULL, 0, NULL, (DWORD *) &n, NULL))
|
|
{
|
|
__seterrno ();
|
|
return -1;
|
|
}
|
|
break;
|
|
default:
|
|
return fhandler_base::ioctl (cmd, p);
|
|
break;
|
|
}
|
|
*(int *) p = n;
|
|
return 0;
|
|
}
|
|
|
|
int __stdcall
|
|
fhandler_pipe::fstatvfs (struct statvfs *sfs)
|
|
{
|
|
set_errno (EBADF);
|
|
return -1;
|
|
}
|
|
|
|
#define DEFAULT_PIPEBUFSIZE (16 * PIPE_BUF)
|
|
|
|
extern "C" int
|
|
pipe (int filedes[2])
|
|
{
|
|
extern DWORD binmode;
|
|
fhandler_pipe *fhs[2];
|
|
int res = fhandler_pipe::create (fhs, DEFAULT_PIPEBUFSIZE,
|
|
(!binmode || binmode == O_BINARY)
|
|
? O_BINARY : O_TEXT);
|
|
if (res == 0)
|
|
{
|
|
cygheap_fdnew fdin;
|
|
cygheap_fdnew fdout (fdin, false);
|
|
fdin = fhs[0];
|
|
fdout = fhs[1];
|
|
filedes[0] = fdin;
|
|
filedes[1] = fdout;
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
extern "C" int
|
|
_pipe (int filedes[2], unsigned int psize, int mode)
|
|
{
|
|
fhandler_pipe *fhs[2];
|
|
int res = fhandler_pipe::create (fhs, psize, mode);
|
|
/* This type of pipe is not interruptible so set the appropriate flag. */
|
|
if (!res)
|
|
{
|
|
cygheap_fdnew fdin;
|
|
cygheap_fdnew fdout (fdin, false);
|
|
fhs[0]->uninterruptible_io (true);
|
|
fdin = fhs[0];
|
|
fdout = fhs[1];
|
|
filedes[0] = fdin;
|
|
filedes[1] = fdout;
|
|
}
|
|
|
|
return res;
|
|
}
|