* fhandler.h (fhandler_pipe::create_selectable): Remove optional argument, take

an options argument for CreateNamedPipe/CreateFile.  Change handle arguments to
expect pointers.
(fhandler_fifo::fifo_state): Delete.
(fhandler_fifo::dummy_client): Ditto.
(fhandler_fifo::open_nonserver): Ditto.
(fhandler_fifo::wait_state): Ditto.
(fhandler_fifo::raw_write): Ditto.
(fhandler_fifo::read_ready): New field.
(fhandler_fifo::write_ready): Ditto.
(fhandler_fifo::wait): Modify argument.
(fhandler_fifo::fifo_name): Add a new argument.
(fhandler_fifo::fixup_after_fork): New function.
* fhandler_fifo.cc (fhandler_fifo::fhandler_fifo): Remove initialization of
expunged elements.  Initialize new handles to NULL.
(fhandler_fifo::open_nonserver): Delete.
(fnevent): New macro for creating a named event.
(fnpipe): New macro for creating a unique named pipe name.
(create_pipe): New macro for simplification of named pipe creation.
(fhandler_fifo::fifo_name): Use new argument when creating a shared name.
(fhandler_fifo::open): Rewrite.  Use events to synchronize.
(pure_debug_printf): New macro, active only when DEBUGGING.
(fhandler_fifo::wait): Rewrite to wait for new fifo events which are supplied
as a parameter.
(fhandler_fifo::raw_read): Rewrite to use handle mechanism to detect
client-side disconnect.
(fhandler_fifo::raw_write): Delete.
(fhandler_fifo::close): Remove accommodations for expunged fields.  Close event
handles.
(fhandler_fifo::dup): Remove accommodations for expunged fields.  Duplicate
event handles.
(fhandler_fifo::fixup_after_fork): New function.  Perform fixups on event
handles.
(fhandler_fifo::set_close_on_exec): Remove accommodations for expunged fields.
Set inheritance for new handle fields.
* miscfuncs.cc (CreatePipeOverlapped): Accommodate changes in
fhandler_pipe::create_selectable.
* tty.cc (tty::not_allocated): Ditto.
* pipe.cc (fhandler_pipe::create): Ditto.
(fhandler_pipe::create_selectable): Accept an extra open_mode argument.  Pass
arguments by reference and allow opening one end of the pipe at a time.
* sys/strace.h (debug_only_printf): Define new macro which calls debug_printf
only when DEBUGGING is defined.
This commit is contained in:
Christopher Faylor
2011-10-30 04:50:36 +00:00
parent 673a691372
commit cd071d1363
9 changed files with 449 additions and 369 deletions

View File

@ -24,52 +24,27 @@
#include "ntdll.h"
fhandler_fifo::fhandler_fifo ():
fhandler_base_overlapped (), wait_state (fifo_unknown), dummy_client (NULL)
fhandler_base_overlapped (),
read_ready (NULL), write_ready (NULL)
{
max_atomic_write = DEFAULT_PIPEBUFSIZE;
need_fork_fixup (true);
}
HANDLE
fhandler_fifo::open_nonserver (const char *npname, unsigned low_flags,
LPSECURITY_ATTRIBUTES sa_buf)
{
DWORD mode = 0;
if (low_flags == O_RDONLY)
mode = GENERIC_READ;
else if (low_flags == O_WRONLY)
mode = GENERIC_WRITE;
else
mode = GENERIC_READ | GENERIC_WRITE;
while (1)
{
HANDLE h = CreateFile (npname, mode, 0, sa_buf, OPEN_EXISTING,
FILE_FLAG_OVERLAPPED, NULL);
if (h != INVALID_HANDLE_VALUE || GetLastError () != ERROR_PIPE_NOT_CONNECTED)
return h;
if (IsEventSignalled (signal_arrived))
{
set_errno (EINTR);
return NULL;
}
}
}
#define fnevent(w) fifo_name (npbuf, w "-event")
#define fnpipe() fifo_name (npbuf, "fifo")
#define create_pipe(r, w) \
fhandler_pipe::create_selectable (sa_buf, (r), (w), 0, fnpipe (), open_mode)
char *
fhandler_fifo::fifo_name (char *buf)
fhandler_fifo::fifo_name (char *buf, const char *what)
{
/* Generate a semi-unique name to associate with this fifo. */
__small_sprintf (buf, "\\\\.\\pipe\\__cygfifo__%S_%08x_%016X",
&installation_key, get_dev (), get_ino ());
__small_sprintf (buf, "%s.%08x.%016X", what, get_dev (),
get_ino ());
return buf;
}
#define FIFO_PIPE_MODE (PIPE_TYPE_BYTE | PIPE_READMODE_BYTE)
#define FIFO_BUF_SIZE 4096
#define cnp(m, s) CreateNamedPipe(npname, (m), FIFO_PIPE_MODE, \
PIPE_UNLIMITED_INSTANCES, (s), (s), \
NMPWAIT_WAIT_FOREVER, sa_buf)
inline PSECURITY_ATTRIBUTES
sec_user_cloexec (bool cloexec, PSECURITY_ATTRIBUTES sa, PSID sid)
{
@ -79,207 +54,242 @@ sec_user_cloexec (bool cloexec, PSECURITY_ATTRIBUTES sa, PSID sid)
int
fhandler_fifo::open (int flags, mode_t)
{
int res = 1;
char npname[MAX_PATH];
enum
{
success,
error_errno_set,
error_set_errno
} res;
bool reader, writer;
DWORD open_mode = FILE_FLAG_OVERLAPPED;
fifo_name (npname);
unsigned low_flags = flags & O_ACCMODE;
DWORD mode = 0;
if (low_flags == O_WRONLY)
mode = PIPE_ACCESS_OUTBOUND;
else if (low_flags == O_RDONLY || low_flags == O_RDWR)
mode = PIPE_ACCESS_DUPLEX;
/* Determine what we're doing with this fhandler: reading, writing, both */
switch (flags & O_ACCMODE)
{
case O_RDONLY:
reader = true;
writer = false;
break;
case O_WRONLY:
writer = true;
reader = false;
break;
case O_RDWR:
reader = true;
writer = true;
open_mode |= PIPE_ACCESS_DUPLEX;
break;
default:
set_errno (EINVAL);
res = error_errno_set;
goto out;
}
set_flags (flags);
char char_sa_buf[1024];
LPSECURITY_ATTRIBUTES sa_buf;
sa_buf = sec_user_cloexec (flags & O_CLOEXEC, (PSECURITY_ATTRIBUTES) char_sa_buf,
cygheap->user.sid());
char npbuf[MAX_PATH];
/* Create control events for this named pipe */
if (!(read_ready = CreateEvent (sa_buf, true, false, fnevent ("r"))))
{
debug_printf ("CreatEvent for %s failed, %E", npbuf);
res = error_set_errno;
goto out;
}
if (!(write_ready = CreateEvent (sa_buf, true, false, fnevent ("w"))))
{
debug_printf ("CreatEvent for %s failed, %E", npbuf);
res = error_set_errno;
goto out;
}
/* If we're reading, create the pipe, signal that we're ready and wait for
a writer.
FIXME: Probably need to special case O_RDWR case. */
if (!reader)
/* We are not a reader */;
else if (create_pipe (&get_io_handle (), NULL))
{
debug_printf ("create of reader failed");
res = error_set_errno;
goto out;
}
else if (!SetEvent (read_ready))
{
debug_printf ("SetEvent for read_ready failed, %E");
res = error_set_errno;
goto out;
}
else if (!writer && !wait (write_ready))
{
debug_printf ("wait for write_ready failed, %E");
res = error_errno_set;
goto out;
}
/* If we're writing, it's a little tricky since it is possible that
we're attempting to open the other end of a pipe which is already
connected. In that case, we detect ERROR_PIPE_BUSY, reset the
read_ready event and wait for the reader to allow us to connect
by signalling read_ready.
Once the pipe has been set up, we signal write_ready. */
if (writer)
{
int err;
while (1)
if (!wait (read_ready))
{
res = error_errno_set;
goto out;
}
else if ((err = create_pipe (NULL, &get_io_handle ())) == 0)
break;
else if (err == ERROR_PIPE_BUSY)
{
debug_only_printf ("pipe busy");
ResetEvent (read_ready);
}
else
{
debug_printf ("create of writer failed");
res = error_set_errno;
goto out;
}
if (!SetEvent (write_ready))
{
debug_printf ("SetEvent for write_ready failed, %E");
res = error_set_errno;
goto out;
}
}
/* If setup_overlapped() succeeds (and why wouldn't it?) we are all set. */
if (setup_overlapped () == 0)
res = success;
else
{
set_errno (EINVAL);
res = 0;
debug_printf ("setup_overlapped failed, %E");
res = error_set_errno;
}
if (res)
out:
if (res == error_set_errno)
__seterrno ();
if (res != success)
{
char char_sa_buf[1024];
LPSECURITY_ATTRIBUTES sa_buf =
sec_user_cloexec (flags & O_CLOEXEC, (PSECURITY_ATTRIBUTES) char_sa_buf,
cygheap->user.sid());
bool do_seterrno = true;
HANDLE h;
bool nonblocking_write = !!((flags & (O_WRONLY | O_NONBLOCK)) == (O_WRONLY | O_NONBLOCK));
wait_state = fifo_unknown;
if (mode != PIPE_ACCESS_OUTBOUND)
if (read_ready)
{
h = cnp (mode | FILE_FLAG_OVERLAPPED, FIFO_BUF_SIZE);
wait_state = fifo_wait_for_client;
CloseHandle (read_ready);
read_ready = NULL;
}
else
if (write_ready)
{
h = open_nonserver (npname, low_flags, sa_buf);
if (h != INVALID_HANDLE_VALUE)
wait_state = fifo_ok;
else if (nonblocking_write)
{
set_errno (ENXIO);
do_seterrno = false;
}
else if ((h = cnp (PIPE_ACCESS_DUPLEX, 1)) != INVALID_HANDLE_VALUE)
{
if ((dummy_client = open_nonserver (npname, low_flags, sa_buf))
!= INVALID_HANDLE_VALUE)
{
wait_state = fifo_wait_for_server;
ProtectHandle (dummy_client);
}
else
{
DWORD saveerr = GetLastError ();
CloseHandle (h);
h = INVALID_HANDLE_VALUE;
SetLastError (saveerr);
}
}
}
if (h == INVALID_HANDLE_VALUE)
{
if (do_seterrno)
__seterrno ();
res = 0;
}
else if (setup_overlapped ())
{
CloseHandle (h);
__seterrno ();
res = 0;
}
else
{
set_io_handle (h);
set_flags (flags);
res = 1;
CloseHandle (write_ready);
write_ready = NULL;
}
if (get_io_handle ())
CloseHandle (get_io_handle ());
}
debug_printf ("returning %d, errno %d", res, get_errno ());
return res;
debug_printf ("res %d", res);
return res == success;
}
bool
fhandler_fifo::wait (bool iswrite)
fhandler_fifo::wait (HANDLE h)
{
DWORD ninstances;
switch (wait_state)
#ifdef DEBUGGING
const char *what;
if (h == read_ready)
what = "reader";
else if (h == write_ready)
what = "writer";
else
what = "overlapped event";
#endif
HANDLE w4[3] = {h, signal_arrived, pthread::get_cancel_event ()};
/* Set the wait to zero for non-blocking I/O-related events. */
DWORD wait = ((h == read_ready || h == write_ready)
&& get_flags () & O_NONBLOCK) ? 0 : INFINITE;
debug_only_printf ("waiting for %s", what);
/* Wait for the event. Set errno, as appropriate if something goes wrong. */
switch (WaitForMultipleObjects (3, w4, false, wait))
{
case fifo_wait_for_next_client:
DisconnectNamedPipe (get_handle ());
if (!GetNamedPipeHandleState (get_handle (), NULL, &ninstances, NULL, NULL, NULL, 0))
case WAIT_OBJECT_0:
debug_only_printf ("successfully waited for %s", what);
return true;
case WAIT_TIMEOUT:
if (h == write_ready)
{
__seterrno ();
wait_state = fifo_error;
debug_only_printf ("wait timed out waiting for write but will still open reader since non-blocking mode");
return true;
}
else
{
set_errno (ENXIO);
return false;
}
if (ninstances <= 1)
{
wait_state = fifo_eof;
return false;
}
case fifo_wait_for_client:
{
DWORD dummy_bytes;
while (1)
{
int res = ConnectNamedPipe (get_handle (), get_overlapped ());
if (GetLastError () != ERROR_NO_DATA && GetLastError () != ERROR_PIPE_CONNECTED)
{
res = wait_overlapped (res, iswrite, &dummy_bytes, false);
if (!res)
{
if (get_errno () != EINTR)
wait_state = fifo_error;
else if (!_my_tls.call_signal_handler ())
wait_state = fifo_eintr;
else
continue;
return false;
}
}
wait_state = fifo_ok;
break;
}
}
break;
case fifo_wait_for_server:
char npname[MAX_PATH];
fifo_name (npname);
char char_sa_buf[1024];
LPSECURITY_ATTRIBUTES sa_buf;
sa_buf = sec_user_cloexec (close_on_exec (),
(PSECURITY_ATTRIBUTES) char_sa_buf,
cygheap->user.sid());
while (1)
{
if (WaitNamedPipe (npname, 10))
/* connected, maybe */;
else if (GetLastError () != ERROR_SEM_TIMEOUT)
{
__seterrno ();
return false;
}
else if (!IsEventSignalled (signal_arrived))
continue;
else if (_my_tls.call_signal_handler ())
continue;
else
{
set_errno (EINTR);
return false;
}
HANDLE h = open_nonserver (npname, get_flags () & O_ACCMODE, sa_buf);
if (h != INVALID_HANDLE_VALUE)
{
ForceCloseHandle (get_handle ());
ForceCloseHandle (dummy_client);
dummy_client = NULL;
wait_state = fifo_ok;
set_io_handle (h);
break;
}
if (GetLastError () == ERROR_PIPE_LISTENING)
continue;
else
{
__seterrno ();
return false;
}
}
case WAIT_OBJECT_0 + 1:
debug_only_printf ("interrupted by signal while waiting for %s", what);
set_errno (EINTR);
return false;
case WAIT_OBJECT_0 + 2:
debug_only_printf ("cancellable interruption while waiting for %s", what);
pthread::static_cancel_self (); /* never returns */
break;
default:
break;
}
return true;
debug_only_printf ("unknown error while waiting for %s", what);
__seterrno ();
return false;
}
}
void __stdcall
fhandler_fifo::raw_read (void *in_ptr, size_t& len)
{
while (wait_state != fifo_eof && wait_state != fifo_error && wait_state != fifo_eintr)
if (!wait (false))
len = (wait_state == fifo_error || wait_state == fifo_eintr) ? (size_t) -1 : 0;
else
{
size_t prev_len = len;
fhandler_base_overlapped::raw_read (in_ptr, len);
if (len)
break;
wait_state = fifo_wait_for_next_client;
len = prev_len;
}
if (wait_state == fifo_eintr)
wait_state = fifo_wait_for_client;
debug_printf ("returning %d, mode %d, %E\n", len, get_errno ());
}
size_t orig_len = len;
for (int i = 0; i < 2; i++)
{
fhandler_base_overlapped::raw_read (in_ptr, len);
if (len || i || WaitForSingleObject (read_ready, 0) == WAIT_OBJECT_0)
break;
/* If we got here, then fhandler_base_overlapped::raw_read returned 0,
indicating "EOF" and something has set read_ready to zero. That means
we should have a client waiting to connect.
FIXME: If the client CTRL-C's the open during this time then this
could hang indefinitely. Maybe implement a timeout? */
if (!DisconnectNamedPipe (get_io_handle ()))
{
debug_printf ("DisconnecttNamedPipe failed, %E");
goto errno_out;
}
else if (!ConnectNamedPipe (get_io_handle (), get_overlapped ())
&& GetLastError () != ERROR_IO_PENDING)
{
debug_printf ("ConnectNamedPipe failed, %E");
goto errno_out;
}
else if (!SetEvent (read_ready))
{
debug_printf ("SetEvent (read_ready) failed, %E");
goto errno_out;
}
else if (!wait (get_overlapped_buffer ()->hEvent))
goto errout; /* If wait() fails, errno is set so no need to set it */
len = orig_len; /* Reset since raw_read above set it to zero. */
}
return;
ssize_t __stdcall
fhandler_fifo::raw_write (const void *ptr, size_t len)
{
return wait (true) ? fhandler_base_overlapped::raw_write (ptr, len) : -1;
errno_out:
__seterrno ();
errout:
len = -1;
}
int __stdcall
@ -293,41 +303,52 @@ fhandler_fifo::fstatvfs (struct statvfs *sfs)
int
fhandler_fifo::close ()
{
wait_state = fifo_eof;
if (dummy_client)
{
ForceCloseHandle (dummy_client);
dummy_client = NULL;
}
CloseHandle (read_ready);
CloseHandle (write_ready);
return fhandler_base::close ();
}
int
fhandler_fifo::dup (fhandler_base *child, int flags)
{
int res = fhandler_base_overlapped::dup (child, flags);
fhandler_fifo *fifo_child = (fhandler_fifo *) child;
if (res == 0 && dummy_client)
if (fhandler_base_overlapped::dup (child, flags))
{
bool dres = DuplicateHandle (GetCurrentProcess (), dummy_client,
GetCurrentProcess (),
&fifo_child->dummy_client, 0,
TRUE, DUPLICATE_SAME_ACCESS);
if (!dres)
{
fifo_child->dummy_client = NULL;
child->close ();
__seterrno ();
res = -1;
}
__seterrno ();
return -1;
}
return res;
fhandler_fifo *fhf = (fhandler_fifo *) child;
if (!DuplicateHandle (GetCurrentProcess (), read_ready,
GetCurrentProcess (), &fhf->read_ready,
0, true, DUPLICATE_SAME_ACCESS))
{
fhf->close ();
__seterrno ();
return -1;
}
if (!DuplicateHandle (GetCurrentProcess (), write_ready,
GetCurrentProcess (), &fhf->write_ready,
0, true, DUPLICATE_SAME_ACCESS))
{
CloseHandle (fhf->read_ready);
fhf->close ();
__seterrno ();
return -1;
}
return 0;
}
void
fhandler_fifo::fixup_after_fork (HANDLE parent)
{
fhandler_base_overlapped::fixup_after_fork (parent);
fork_fixup (parent, read_ready, "read_ready");
fork_fixup (parent, write_ready, "write_ready");
}
void
fhandler_fifo::set_close_on_exec (bool val)
{
fhandler_base::set_close_on_exec (val);
if (dummy_client)
set_no_inheritance (dummy_client, val);
set_no_inheritance (read_ready, val);
set_no_inheritance (write_ready, val);
}