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git://sourceware.org/git/newlib-cygwin.git
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71cd54794f
According to Posix, a FIFO open for reading is at EOF if it is empty and there are no writers open. The only way to test this is to poll the fifo_client_handlers as in raw_read and select.cc:peek_fifo. The current hit_eof instead relies on the value of nconnected, which can be out of date. On the one hand, it doesn't take into account writers that were connected but have since closed. On the other hand, it doesn't take into account writers that are in the process of opening but haven't yet connected. Fix this by introducing a maybe_eof method that tentatively assumes EOF if there are no connected writers after polling. Then check for writers currently opening (via a new 'writer_opening' event), and wait for the fifo_reader_thread to record any new connection that was made while we were polling. To handle the needs of peek_fifo, replace the get_fc_handle method by a get_fc_handler method, and add a fifo_client_handler::get_state method. Remove the is_connected method, which was used only in peek_fifo and is no longer needed. Remove the nconnected data member, which was used only for the flawed hit_eof. Add some comments about events to fhandler.h.
1098 lines
26 KiB
C++
1098 lines
26 KiB
C++
/* fhandler_fifo.cc - See fhandler.h for a description of the fhandler classes.
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This file is part of Cygwin.
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This software is a copyrighted work licensed under the terms of the
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Cygwin license. Please consult the file "CYGWIN_LICENSE" for
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details. */
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#include "winsup.h"
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#include <w32api/winioctl.h>
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#include "miscfuncs.h"
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#include "cygerrno.h"
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#include "security.h"
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#include "path.h"
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#include "fhandler.h"
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#include "dtable.h"
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#include "cygheap.h"
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#include "sigproc.h"
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#include "cygtls.h"
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#include "shared_info.h"
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#include "ntdll.h"
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#include "cygwait.h"
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/*
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Overview:
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Currently a FIFO can be opened once for reading and multiple
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times for writing. Any attempt to open the FIFO a second time
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for reading fails with EACCES (from STATUS_ACCESS_DENIED).
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When a FIFO is opened for reading,
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fhandler_fifo::create_pipe_instance is called to create the first
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instance of a Windows named pipe server (Windows terminology). A
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"listen_client" thread is also started; it waits for pipe clients
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(Windows terminology again) to connect. This happens every time
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a process opens the FIFO for writing.
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The listen_client thread creates new instances of the pipe server
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as needed, so that there is always an instance available for a
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writer to connect to.
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The reader maintains a list of "fifo_client_handlers", one for
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each pipe instance. A fifo_client_handler manages the connection
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between the pipe instance and a writer connected to that pipe
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instance.
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TODO: Allow a FIFO to be opened multiple times for reading.
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Maybe this could be done by using shared memory, so that all
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readers could have access to the same list of writers.
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*/
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/* This is only to be used for writers. When reading,
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STATUS_PIPE_EMPTY simply means there's no data to be read. */
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#define STATUS_PIPE_IS_CLOSED(status) \
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({ NTSTATUS _s = (status); \
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_s == STATUS_PIPE_CLOSING \
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|| _s == STATUS_PIPE_BROKEN \
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|| _s == STATUS_PIPE_EMPTY; })
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#define STATUS_PIPE_NO_INSTANCE_AVAILABLE(status) \
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({ NTSTATUS _s = (status); \
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_s == STATUS_INSTANCE_NOT_AVAILABLE \
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|| _s == STATUS_PIPE_NOT_AVAILABLE \
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|| _s == STATUS_PIPE_BUSY; })
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fhandler_fifo::fhandler_fifo ():
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fhandler_base (),
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read_ready (NULL), write_ready (NULL), writer_opening (NULL),
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listen_client_thr (NULL), lct_termination_evt (NULL), _maybe_eof (false), nhandlers (0),
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reader (false), writer (false), duplexer (false),
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max_atomic_write (DEFAULT_PIPEBUFSIZE)
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{
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pipe_name_buf[0] = L'\0';
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need_fork_fixup (true);
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}
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PUNICODE_STRING
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fhandler_fifo::get_pipe_name ()
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{
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if (!pipe_name_buf[0])
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{
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__small_swprintf (pipe_name_buf, L"%S-fifo.%08x.%016X",
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&cygheap->installation_key, get_dev (), get_ino ());
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RtlInitUnicodeString (&pipe_name, pipe_name_buf);
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}
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return &pipe_name;
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}
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inline PSECURITY_ATTRIBUTES
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sec_user_cloexec (bool cloexec, PSECURITY_ATTRIBUTES sa, PSID sid)
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{
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return cloexec ? sec_user_nih (sa, sid) : sec_user (sa, sid);
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}
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static HANDLE
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create_event ()
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{
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NTSTATUS status;
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OBJECT_ATTRIBUTES attr;
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HANDLE evt = NULL;
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InitializeObjectAttributes (&attr, NULL, 0, NULL, NULL);
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status = NtCreateEvent (&evt, EVENT_ALL_ACCESS, &attr,
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NotificationEvent, FALSE);
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if (!NT_SUCCESS (status))
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__seterrno_from_nt_status (status);
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return evt;
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}
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static void
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set_pipe_non_blocking (HANDLE ph, bool nonblocking)
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{
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NTSTATUS status;
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IO_STATUS_BLOCK io;
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FILE_PIPE_INFORMATION fpi;
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fpi.ReadMode = FILE_PIPE_MESSAGE_MODE;
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fpi.CompletionMode = nonblocking ? FILE_PIPE_COMPLETE_OPERATION
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: FILE_PIPE_QUEUE_OPERATION;
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status = NtSetInformationFile (ph, &io, &fpi, sizeof fpi,
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FilePipeInformation);
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if (!NT_SUCCESS (status))
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debug_printf ("NtSetInformationFile(FilePipeInformation): %y", status);
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}
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NTSTATUS
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fhandler_fifo::npfs_handle (HANDLE &nph)
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{
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static NO_COPY SRWLOCK npfs_lock;
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static NO_COPY HANDLE npfs_dirh;
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NTSTATUS status = STATUS_SUCCESS;
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OBJECT_ATTRIBUTES attr;
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IO_STATUS_BLOCK io;
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/* Lockless after first call. */
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if (npfs_dirh)
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{
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nph = npfs_dirh;
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return STATUS_SUCCESS;
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}
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AcquireSRWLockExclusive (&npfs_lock);
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if (!npfs_dirh)
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{
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InitializeObjectAttributes (&attr, &ro_u_npfs, 0, NULL, NULL);
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status = NtOpenFile (&npfs_dirh, FILE_READ_ATTRIBUTES | SYNCHRONIZE,
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&attr, &io, FILE_SHARE_READ | FILE_SHARE_WRITE,
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0);
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}
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ReleaseSRWLockExclusive (&npfs_lock);
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if (NT_SUCCESS (status))
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nph = npfs_dirh;
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return status;
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}
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/* Called when a FIFO is first opened for reading and again each time
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a new client handler is needed. Each pipe instance is created in
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blocking mode so that we can easily wait for a connection. After
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it is connected, it is put in nonblocking mode. */
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HANDLE
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fhandler_fifo::create_pipe_instance (bool first)
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{
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NTSTATUS status;
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HANDLE npfsh;
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HANDLE ph = NULL;
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ACCESS_MASK access;
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OBJECT_ATTRIBUTES attr;
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IO_STATUS_BLOCK io;
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ULONG hattr;
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ULONG sharing;
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ULONG nonblocking = FILE_PIPE_QUEUE_OPERATION;
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ULONG max_instances = -1;
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LARGE_INTEGER timeout;
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status = npfs_handle (npfsh);
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if (!NT_SUCCESS (status))
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{
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__seterrno_from_nt_status (status);
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return NULL;
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}
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access = GENERIC_READ | FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES
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| SYNCHRONIZE;
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sharing = FILE_SHARE_READ | FILE_SHARE_WRITE;
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hattr = openflags & O_CLOEXEC ? 0 : OBJ_INHERIT;
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if (first)
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hattr |= OBJ_CASE_INSENSITIVE;
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InitializeObjectAttributes (&attr, get_pipe_name (),
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hattr, npfsh, NULL);
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timeout.QuadPart = -500000;
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status = NtCreateNamedPipeFile (&ph, access, &attr, &io, sharing,
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first ? FILE_CREATE : FILE_OPEN, 0,
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FILE_PIPE_MESSAGE_TYPE
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| FILE_PIPE_REJECT_REMOTE_CLIENTS,
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FILE_PIPE_MESSAGE_MODE,
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nonblocking, max_instances,
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DEFAULT_PIPEBUFSIZE, DEFAULT_PIPEBUFSIZE,
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&timeout);
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if (!NT_SUCCESS (status))
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__seterrno_from_nt_status (status);
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return ph;
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}
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/* Connect to a pipe instance. */
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NTSTATUS
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fhandler_fifo::open_pipe (HANDLE& ph)
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{
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NTSTATUS status;
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HANDLE npfsh;
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ACCESS_MASK access;
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OBJECT_ATTRIBUTES attr;
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IO_STATUS_BLOCK io;
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ULONG sharing;
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status = npfs_handle (npfsh);
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if (!NT_SUCCESS (status))
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return status;
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access = GENERIC_WRITE | SYNCHRONIZE;
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InitializeObjectAttributes (&attr, get_pipe_name (),
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openflags & O_CLOEXEC ? 0 : OBJ_INHERIT,
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npfsh, NULL);
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sharing = FILE_SHARE_READ | FILE_SHARE_WRITE;
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status = NtOpenFile (&ph, access, &attr, &io, sharing, 0);
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return status;
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}
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int
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fhandler_fifo::add_client_handler ()
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{
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int ret = -1;
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fifo_client_handler fc;
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HANDLE ph = NULL;
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bool first = (nhandlers == 0);
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if (nhandlers == MAX_CLIENTS)
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{
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set_errno (EMFILE);
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goto out;
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}
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ph = create_pipe_instance (first);
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if (!ph)
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goto out;
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else
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{
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ret = 0;
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fc.h = ph;
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fc.state = fc_listening;
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fc_handler[nhandlers++] = fc;
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}
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out:
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return ret;
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}
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void
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fhandler_fifo::delete_client_handler (int i)
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{
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fc_handler[i].close ();
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if (i < --nhandlers)
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memmove (fc_handler + i, fc_handler + i + 1,
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(nhandlers - i) * sizeof (fc_handler[i]));
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}
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/* Just hop to the listen_client_thread method. */
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DWORD WINAPI
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listen_client_func (LPVOID param)
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{
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fhandler_fifo *fh = (fhandler_fifo *) param;
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return fh->listen_client_thread ();
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}
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/* Start a thread that listens for client connections. */
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bool
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fhandler_fifo::listen_client ()
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{
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if (!(lct_termination_evt = create_event ()))
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return false;
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listen_client_thr = CreateThread (NULL, PREFERRED_IO_BLKSIZE,
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listen_client_func, (PVOID) this, 0, NULL);
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if (!listen_client_thr)
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{
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__seterrno ();
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HANDLE evt = InterlockedExchangePointer (&lct_termination_evt, NULL);
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if (evt)
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NtClose (evt);
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return false;
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}
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return true;
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}
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void
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fhandler_fifo::record_connection (fifo_client_handler& fc,
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fifo_client_connect_state s)
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{
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SetEvent (write_ready);
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fc.state = s;
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maybe_eof (false);
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ResetEvent (writer_opening);
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set_pipe_non_blocking (fc.h, true);
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}
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DWORD
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fhandler_fifo::listen_client_thread ()
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{
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HANDLE conn_evt;
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if (!(conn_evt = CreateEvent (NULL, false, false, NULL)))
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api_fatal ("Can't create connection event, %E");
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while (1)
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{
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/* Cleanup the fc_handler list. */
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fifo_client_lock ();
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int i = 0;
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while (i < nhandlers)
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{
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if (fc_handler[i].state < fc_connected)
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delete_client_handler (i);
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else
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i++;
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}
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fifo_client_unlock ();
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/* Create a new client handler. */
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if (add_client_handler () < 0)
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api_fatal ("Can't add a client handler, %E");
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/* Allow a writer to open. */
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SetEvent (read_ready);
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/* Listen for a writer to connect to the new client handler. */
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fifo_client_handler& fc = fc_handler[nhandlers - 1];
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NTSTATUS status;
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IO_STATUS_BLOCK io;
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bool cancel = false;
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status = NtFsControlFile (fc.h, conn_evt, NULL, NULL, &io,
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FSCTL_PIPE_LISTEN, NULL, 0, NULL, 0);
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if (status == STATUS_PENDING)
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{
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HANDLE w[2] = { conn_evt, lct_termination_evt };
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DWORD waitret = WaitForMultipleObjects (2, w, false, INFINITE);
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switch (waitret)
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{
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case WAIT_OBJECT_0:
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status = io.Status;
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break;
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case WAIT_OBJECT_0 + 1:
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status = STATUS_THREAD_IS_TERMINATING;
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cancel = true;
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break;
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default:
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api_fatal ("WFMO failed, %E");
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}
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}
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HANDLE ph = NULL;
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NTSTATUS status1;
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fifo_client_lock ();
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switch (status)
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{
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case STATUS_SUCCESS:
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case STATUS_PIPE_CONNECTED:
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record_connection (fc);
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break;
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case STATUS_PIPE_CLOSING:
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record_connection (fc, fc_closing);
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break;
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case STATUS_THREAD_IS_TERMINATING:
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/* Try to connect a bogus client. Otherwise fc is still
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listening, and the next connection might not get recorded. */
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status1 = open_pipe (ph);
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WaitForSingleObject (conn_evt, INFINITE);
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if (NT_SUCCESS (status1))
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/* Bogus cilent connected. */
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delete_client_handler (nhandlers - 1);
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else
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/* Did a real client connect? */
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switch (io.Status)
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{
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case STATUS_SUCCESS:
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case STATUS_PIPE_CONNECTED:
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record_connection (fc);
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break;
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case STATUS_PIPE_CLOSING:
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record_connection (fc, fc_closing);
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break;
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default:
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debug_printf ("NtFsControlFile status %y after failing to connect bogus client or real client", io.Status);
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fc.state = fc_unknown;
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break;
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}
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break;
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default:
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break;
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}
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fifo_client_unlock ();
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if (ph)
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NtClose (ph);
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if (cancel)
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goto out;
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}
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out:
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if (conn_evt)
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NtClose (conn_evt);
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ResetEvent (read_ready);
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return 0;
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}
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int
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fhandler_fifo::open (int flags, mode_t)
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{
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enum
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{
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success,
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error_errno_set,
|
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error_set_errno
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} res;
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|
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if (flags & O_PATH)
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return open_fs (flags);
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|
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/* Determine what we're doing with this fhandler: reading, writing, both */
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switch (flags & O_ACCMODE)
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{
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case O_RDONLY:
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reader = true;
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break;
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case O_WRONLY:
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writer = true;
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break;
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case O_RDWR:
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reader = true;
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duplexer = true;
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break;
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default:
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set_errno (EINVAL);
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res = error_errno_set;
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goto out;
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}
|
|
|
|
debug_only_printf ("reader %d, writer %d, duplexer %d", reader, writer, duplexer);
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set_flags (flags);
|
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if (reader && !duplexer)
|
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nohandle (true);
|
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|
|
/* Create control events for this named pipe */
|
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char char_sa_buf[1024];
|
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LPSECURITY_ATTRIBUTES sa_buf;
|
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sa_buf = sec_user_cloexec (flags & O_CLOEXEC, (PSECURITY_ATTRIBUTES) char_sa_buf,
|
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cygheap->user.sid());
|
|
|
|
char npbuf[MAX_PATH];
|
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__small_sprintf (npbuf, "r-event.%08x.%016X", get_dev (), get_ino ());
|
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if (!(read_ready = CreateEvent (sa_buf, false, false, npbuf)))
|
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{
|
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debug_printf ("CreateEvent for %s failed, %E", npbuf);
|
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res = error_set_errno;
|
|
goto out;
|
|
}
|
|
npbuf[0] = 'w';
|
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if (!(write_ready = CreateEvent (sa_buf, true, false, npbuf)))
|
|
{
|
|
debug_printf ("CreateEvent for %s failed, %E", npbuf);
|
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res = error_set_errno;
|
|
goto out;
|
|
}
|
|
npbuf[0] = 'o';
|
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if (!(writer_opening = CreateEvent (sa_buf, true, false, npbuf)))
|
|
{
|
|
debug_printf ("CreateEvent for %s failed, %E", npbuf);
|
|
res = error_set_errno;
|
|
goto out;
|
|
}
|
|
|
|
/* If we're a duplexer, create the pipe and the first client handler. */
|
|
if (duplexer)
|
|
{
|
|
HANDLE ph = NULL;
|
|
|
|
if (add_client_handler () < 0)
|
|
{
|
|
res = error_errno_set;
|
|
goto out;
|
|
}
|
|
NTSTATUS status = open_pipe (ph);
|
|
if (NT_SUCCESS (status))
|
|
{
|
|
record_connection (fc_handler[0]);
|
|
set_handle (ph);
|
|
set_pipe_non_blocking (ph, flags & O_NONBLOCK);
|
|
}
|
|
else
|
|
{
|
|
__seterrno_from_nt_status (status);
|
|
res = error_errno_set;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* If we're reading, start the listen_client thread (which should
|
|
signal read_ready), and wait for a writer. */
|
|
if (reader)
|
|
{
|
|
if (!listen_client ())
|
|
{
|
|
debug_printf ("create of listen_client thread failed");
|
|
res = error_errno_set;
|
|
goto out;
|
|
}
|
|
else if (!duplexer && !wait (write_ready))
|
|
{
|
|
res = error_errno_set;
|
|
goto out;
|
|
}
|
|
else
|
|
{
|
|
init_fixup_before ();
|
|
res = success;
|
|
}
|
|
}
|
|
|
|
/* If we're writing, wait for read_ready and then connect to the
|
|
pipe. This should always succeed quickly if the reader's
|
|
listen_client thread is running. Then signal write_ready. */
|
|
if (writer)
|
|
{
|
|
SetEvent (writer_opening);
|
|
while (1)
|
|
{
|
|
if (!wait (read_ready))
|
|
{
|
|
ResetEvent (writer_opening);
|
|
res = error_errno_set;
|
|
goto out;
|
|
}
|
|
NTSTATUS status = open_pipe (get_handle ());
|
|
if (NT_SUCCESS (status))
|
|
{
|
|
set_pipe_non_blocking (get_handle (), flags & O_NONBLOCK);
|
|
SetEvent (write_ready);
|
|
res = success;
|
|
goto out;
|
|
}
|
|
else if (STATUS_PIPE_NO_INSTANCE_AVAILABLE (status))
|
|
Sleep (1);
|
|
else
|
|
{
|
|
debug_printf ("create of writer failed");
|
|
__seterrno_from_nt_status (status);
|
|
res = error_errno_set;
|
|
ResetEvent (writer_opening);
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
out:
|
|
if (res == error_set_errno)
|
|
__seterrno ();
|
|
if (res != success)
|
|
{
|
|
if (read_ready)
|
|
{
|
|
NtClose (read_ready);
|
|
read_ready = NULL;
|
|
}
|
|
if (write_ready)
|
|
{
|
|
NtClose (write_ready);
|
|
write_ready = NULL;
|
|
}
|
|
if (writer_opening)
|
|
{
|
|
NtClose (writer_opening);
|
|
writer_opening = NULL;
|
|
}
|
|
if (get_handle ())
|
|
NtClose (get_handle ());
|
|
if (listen_client_thr)
|
|
stop_listen_client ();
|
|
}
|
|
debug_printf ("res %d", res);
|
|
return res == success;
|
|
}
|
|
|
|
off_t
|
|
fhandler_fifo::lseek (off_t offset, int whence)
|
|
{
|
|
debug_printf ("(%D, %d)", offset, whence);
|
|
set_errno (ESPIPE);
|
|
return -1;
|
|
}
|
|
|
|
bool
|
|
fhandler_fifo::wait (HANDLE h)
|
|
{
|
|
#ifdef DEBUGGING
|
|
const char *what;
|
|
if (h == read_ready)
|
|
what = "reader";
|
|
else
|
|
what = "writer";
|
|
#endif
|
|
/* 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 (cygwait (h, wait))
|
|
{
|
|
case WAIT_OBJECT_0:
|
|
debug_only_printf ("successfully waited for %s", what);
|
|
return true;
|
|
case WAIT_SIGNALED:
|
|
debug_only_printf ("interrupted by signal while waiting for %s", what);
|
|
set_errno (EINTR);
|
|
return false;
|
|
case WAIT_CANCELED:
|
|
debug_only_printf ("cancellable interruption while waiting for %s", what);
|
|
pthread::static_cancel_self (); /* never returns */
|
|
break;
|
|
case WAIT_TIMEOUT:
|
|
if (h == write_ready)
|
|
{
|
|
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;
|
|
}
|
|
break;
|
|
default:
|
|
debug_only_printf ("unknown error while waiting for %s", what);
|
|
__seterrno ();
|
|
return false;
|
|
}
|
|
}
|
|
|
|
ssize_t __reg3
|
|
fhandler_fifo::raw_write (const void *ptr, size_t len)
|
|
{
|
|
ssize_t ret = -1;
|
|
size_t nbytes = 0;
|
|
ULONG chunk;
|
|
NTSTATUS status = STATUS_SUCCESS;
|
|
IO_STATUS_BLOCK io;
|
|
HANDLE evt = NULL;
|
|
|
|
if (!len)
|
|
return 0;
|
|
|
|
if (len <= max_atomic_write)
|
|
chunk = len;
|
|
else if (is_nonblocking ())
|
|
chunk = len = max_atomic_write;
|
|
else
|
|
chunk = max_atomic_write;
|
|
|
|
/* Create a wait event if the FIFO is in blocking mode. */
|
|
if (!is_nonblocking () && !(evt = CreateEvent (NULL, false, false, NULL)))
|
|
{
|
|
__seterrno ();
|
|
return -1;
|
|
}
|
|
|
|
/* Write in chunks, accumulating a total. If there's an error, just
|
|
return the accumulated total unless the first write fails, in
|
|
which case return -1. */
|
|
while (nbytes < len)
|
|
{
|
|
ULONG_PTR nbytes_now = 0;
|
|
size_t left = len - nbytes;
|
|
ULONG len1;
|
|
DWORD waitret = WAIT_OBJECT_0;
|
|
|
|
if (left > chunk)
|
|
len1 = chunk;
|
|
else
|
|
len1 = (ULONG) left;
|
|
nbytes_now = 0;
|
|
status = NtWriteFile (get_handle (), evt, NULL, NULL, &io,
|
|
(PVOID) ptr, len1, NULL, NULL);
|
|
if (evt && status == STATUS_PENDING)
|
|
{
|
|
waitret = cygwait (evt);
|
|
if (waitret == WAIT_OBJECT_0)
|
|
status = io.Status;
|
|
}
|
|
if (waitret == WAIT_CANCELED)
|
|
status = STATUS_THREAD_CANCELED;
|
|
else if (waitret == WAIT_SIGNALED)
|
|
status = STATUS_THREAD_SIGNALED;
|
|
else if (isclosed ()) /* A signal handler might have closed the fd. */
|
|
{
|
|
if (waitret == WAIT_OBJECT_0)
|
|
set_errno (EBADF);
|
|
else
|
|
__seterrno ();
|
|
}
|
|
else if (NT_SUCCESS (status))
|
|
{
|
|
nbytes_now = io.Information;
|
|
/* NtWriteFile returns success with # of bytes written == 0
|
|
if writing on a non-blocking pipe fails because the pipe
|
|
buffer doesn't have sufficient space. */
|
|
if (nbytes_now == 0)
|
|
set_errno (EAGAIN);
|
|
ptr = ((char *) ptr) + chunk;
|
|
nbytes += nbytes_now;
|
|
}
|
|
else if (STATUS_PIPE_IS_CLOSED (status))
|
|
{
|
|
set_errno (EPIPE);
|
|
raise (SIGPIPE);
|
|
}
|
|
else
|
|
__seterrno_from_nt_status (status);
|
|
if (nbytes_now == 0)
|
|
len = 0; /* Terminate loop. */
|
|
if (nbytes > 0)
|
|
ret = nbytes;
|
|
}
|
|
if (evt)
|
|
NtClose (evt);
|
|
if (status == STATUS_THREAD_SIGNALED && ret < 0)
|
|
set_errno (EINTR);
|
|
else if (status == STATUS_THREAD_CANCELED)
|
|
pthread::static_cancel_self ();
|
|
return ret;
|
|
}
|
|
|
|
/* A reader is at EOF if the pipe is empty and no writers are open.
|
|
hit_eof is called by raw_read and select.cc:peek_fifo if it appears
|
|
that we are at EOF after polling the fc_handlers. We recheck this
|
|
in case a writer opened while we were polling. */
|
|
bool
|
|
fhandler_fifo::hit_eof ()
|
|
{
|
|
bool ret = maybe_eof () && !IsEventSignalled (writer_opening);
|
|
if (ret)
|
|
{
|
|
yield ();
|
|
/* Wait for the reader thread to finish recording any connection. */
|
|
fifo_client_lock ();
|
|
fifo_client_unlock ();
|
|
ret = maybe_eof ();
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* Is the lct running? */
|
|
int
|
|
fhandler_fifo::check_listen_client_thread ()
|
|
{
|
|
int ret = 0;
|
|
|
|
if (listen_client_thr)
|
|
{
|
|
DWORD waitret = WaitForSingleObject (listen_client_thr, 0);
|
|
switch (waitret)
|
|
{
|
|
case WAIT_OBJECT_0:
|
|
NtClose (listen_client_thr);
|
|
break;
|
|
case WAIT_TIMEOUT:
|
|
ret = 1;
|
|
break;
|
|
default:
|
|
debug_printf ("WaitForSingleObject failed, %E");
|
|
ret = -1;
|
|
__seterrno ();
|
|
NtClose (listen_client_thr);
|
|
break;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
void __reg3
|
|
fhandler_fifo::raw_read (void *in_ptr, size_t& len)
|
|
{
|
|
/* Make sure the lct is running. */
|
|
int res = check_listen_client_thread ();
|
|
debug_printf ("lct status %d", res);
|
|
if (res < 0 || (res == 0 && !listen_client ()))
|
|
goto errout;
|
|
|
|
if (!len)
|
|
return;
|
|
|
|
while (1)
|
|
{
|
|
/* Poll the connected clients for input. */
|
|
int nconnected = 0;
|
|
fifo_client_lock ();
|
|
for (int i = 0; i < nhandlers; i++)
|
|
if (fc_handler[i].state >= fc_connected)
|
|
{
|
|
NTSTATUS status;
|
|
IO_STATUS_BLOCK io;
|
|
size_t nbytes = 0;
|
|
|
|
nconnected++;
|
|
status = NtReadFile (fc_handler[i].h, NULL, NULL, NULL,
|
|
&io, in_ptr, len, NULL, NULL);
|
|
switch (status)
|
|
{
|
|
case STATUS_SUCCESS:
|
|
case STATUS_BUFFER_OVERFLOW:
|
|
/* io.Information is supposedly valid. */
|
|
nbytes = io.Information;
|
|
if (nbytes > 0)
|
|
{
|
|
len = nbytes;
|
|
fifo_client_unlock ();
|
|
return;
|
|
}
|
|
break;
|
|
case STATUS_PIPE_EMPTY:
|
|
break;
|
|
case STATUS_PIPE_BROKEN:
|
|
fc_handler[i].state = fc_disconnected;
|
|
nconnected--;
|
|
break;
|
|
default:
|
|
debug_printf ("NtReadFile status %y", status);
|
|
fc_handler[i].state = fc_error;
|
|
nconnected--;
|
|
break;
|
|
}
|
|
}
|
|
maybe_eof (!nconnected && !IsEventSignalled (writer_opening));
|
|
fifo_client_unlock ();
|
|
if (maybe_eof () && hit_eof ())
|
|
{
|
|
len = 0;
|
|
return;
|
|
}
|
|
if (is_nonblocking ())
|
|
{
|
|
set_errno (EAGAIN);
|
|
goto errout;
|
|
}
|
|
else
|
|
{
|
|
/* Allow interruption. */
|
|
DWORD waitret = cygwait (NULL, cw_nowait, cw_cancel | cw_sig_eintr);
|
|
if (waitret == WAIT_CANCELED)
|
|
pthread::static_cancel_self ();
|
|
else if (waitret == WAIT_SIGNALED)
|
|
{
|
|
if (_my_tls.call_signal_handler ())
|
|
continue;
|
|
else
|
|
{
|
|
set_errno (EINTR);
|
|
goto errout;
|
|
}
|
|
}
|
|
}
|
|
/* We might have been closed by a signal handler or another thread. */
|
|
if (isclosed ())
|
|
{
|
|
set_errno (EBADF);
|
|
goto errout;
|
|
}
|
|
/* Don't hog the CPU. */
|
|
Sleep (1);
|
|
}
|
|
errout:
|
|
len = (size_t) -1;
|
|
}
|
|
|
|
int __reg2
|
|
fhandler_fifo::fstatvfs (struct statvfs *sfs)
|
|
{
|
|
if (get_flags () & O_PATH)
|
|
/* We already have a handle. */
|
|
{
|
|
HANDLE h = get_handle ();
|
|
if (h)
|
|
return fstatvfs_by_handle (h, sfs);
|
|
}
|
|
|
|
fhandler_disk_file fh (pc);
|
|
fh.get_device () = FH_FS;
|
|
return fh.fstatvfs (sfs);
|
|
}
|
|
|
|
int
|
|
fifo_client_handler::pipe_state ()
|
|
{
|
|
IO_STATUS_BLOCK io;
|
|
FILE_PIPE_LOCAL_INFORMATION fpli;
|
|
NTSTATUS status;
|
|
|
|
status = NtQueryInformationFile (h, &io, &fpli,
|
|
sizeof (fpli), FilePipeLocalInformation);
|
|
if (!NT_SUCCESS (status))
|
|
{
|
|
debug_printf ("NtQueryInformationFile status %y", status);
|
|
__seterrno_from_nt_status (status);
|
|
return -1;
|
|
}
|
|
else if (fpli.ReadDataAvailable > 0)
|
|
return FILE_PIPE_INPUT_AVAILABLE_STATE;
|
|
else
|
|
return fpli.NamedPipeState;
|
|
}
|
|
|
|
void
|
|
fhandler_fifo::stop_listen_client ()
|
|
{
|
|
HANDLE thr, evt;
|
|
|
|
thr = InterlockedExchangePointer (&listen_client_thr, NULL);
|
|
if (thr)
|
|
{
|
|
if (lct_termination_evt)
|
|
SetEvent (lct_termination_evt);
|
|
WaitForSingleObject (thr, INFINITE);
|
|
NtClose (thr);
|
|
}
|
|
evt = InterlockedExchangePointer (&lct_termination_evt, NULL);
|
|
if (evt)
|
|
NtClose (evt);
|
|
}
|
|
|
|
int
|
|
fhandler_fifo::close ()
|
|
{
|
|
/* Avoid deadlock with lct in case this is called from a signal
|
|
handler or another thread. */
|
|
fifo_client_unlock ();
|
|
stop_listen_client ();
|
|
if (read_ready)
|
|
NtClose (read_ready);
|
|
if (write_ready)
|
|
NtClose (write_ready);
|
|
if (writer_opening)
|
|
NtClose (writer_opening);
|
|
fifo_client_lock ();
|
|
for (int i = 0; i < nhandlers; i++)
|
|
fc_handler[i].close ();
|
|
fifo_client_unlock ();
|
|
return fhandler_base::close ();
|
|
}
|
|
|
|
/* If we have a write handle (i.e., we're a duplexer or a writer),
|
|
keep the nonblocking state of the windows pipe in sync with our
|
|
nonblocking state. */
|
|
int
|
|
fhandler_fifo::fcntl (int cmd, intptr_t arg)
|
|
{
|
|
if (cmd != F_SETFL || nohandle () || (get_flags () & O_PATH))
|
|
return fhandler_base::fcntl (cmd, arg);
|
|
|
|
const bool was_nonblocking = is_nonblocking ();
|
|
int res = fhandler_base::fcntl (cmd, arg);
|
|
const bool now_nonblocking = is_nonblocking ();
|
|
if (now_nonblocking != was_nonblocking)
|
|
set_pipe_non_blocking (get_handle (), now_nonblocking);
|
|
return res;
|
|
}
|
|
|
|
int
|
|
fhandler_fifo::dup (fhandler_base *child, int flags)
|
|
{
|
|
int i = 0;
|
|
fhandler_fifo *fhf = NULL;
|
|
|
|
if (get_flags () & O_PATH)
|
|
return fhandler_base::dup (child, flags);
|
|
|
|
if (fhandler_base::dup (child, flags))
|
|
goto err;
|
|
|
|
fhf = (fhandler_fifo *) child;
|
|
if (!DuplicateHandle (GetCurrentProcess (), read_ready,
|
|
GetCurrentProcess (), &fhf->read_ready,
|
|
0, !(flags & O_CLOEXEC), DUPLICATE_SAME_ACCESS))
|
|
{
|
|
__seterrno ();
|
|
goto err;
|
|
}
|
|
if (!DuplicateHandle (GetCurrentProcess (), write_ready,
|
|
GetCurrentProcess (), &fhf->write_ready,
|
|
0, !(flags & O_CLOEXEC), DUPLICATE_SAME_ACCESS))
|
|
{
|
|
__seterrno ();
|
|
goto err_close_read_ready;
|
|
}
|
|
if (!DuplicateHandle (GetCurrentProcess (), writer_opening,
|
|
GetCurrentProcess (), &fhf->writer_opening,
|
|
0, !(flags & O_CLOEXEC), DUPLICATE_SAME_ACCESS))
|
|
{
|
|
__seterrno ();
|
|
goto err_close_write_ready;
|
|
}
|
|
if (reader)
|
|
{
|
|
/* Make sure the child starts unlocked. */
|
|
fhf->fifo_client_unlock ();
|
|
|
|
fifo_client_lock ();
|
|
for (i = 0; i < nhandlers; i++)
|
|
{
|
|
if (!DuplicateHandle (GetCurrentProcess (), fc_handler[i].h,
|
|
GetCurrentProcess (), &fhf->fc_handler[i].h,
|
|
0, !(flags & O_CLOEXEC), DUPLICATE_SAME_ACCESS))
|
|
{
|
|
__seterrno ();
|
|
break;
|
|
}
|
|
}
|
|
if (i < nhandlers)
|
|
{
|
|
fifo_client_unlock ();
|
|
goto err_close_handlers;
|
|
}
|
|
fifo_client_unlock ();
|
|
if (!fhf->listen_client ())
|
|
goto err_close_handlers;
|
|
fhf->init_fixup_before ();
|
|
}
|
|
return 0;
|
|
err_close_handlers:
|
|
for (int j = 0; j < i; j++)
|
|
fhf->fc_handler[j].close ();
|
|
/* err_close_writer_opening: */
|
|
NtClose (fhf->writer_opening);
|
|
err_close_write_ready:
|
|
NtClose (fhf->write_ready);
|
|
err_close_read_ready:
|
|
NtClose (fhf->read_ready);
|
|
err:
|
|
return -1;
|
|
}
|
|
|
|
void
|
|
fhandler_fifo::init_fixup_before ()
|
|
{
|
|
cygheap->fdtab.inc_need_fixup_before ();
|
|
}
|
|
|
|
void
|
|
fhandler_fifo::fixup_after_fork (HANDLE parent)
|
|
{
|
|
fhandler_base::fixup_after_fork (parent);
|
|
fork_fixup (parent, read_ready, "read_ready");
|
|
fork_fixup (parent, write_ready, "write_ready");
|
|
fork_fixup (parent, writer_opening, "writer_opening");
|
|
if (reader)
|
|
{
|
|
/* Make sure the child starts unlocked. */
|
|
fifo_client_unlock ();
|
|
|
|
fifo_client_lock ();
|
|
for (int i = 0; i < nhandlers; i++)
|
|
fork_fixup (parent, fc_handler[i].h, "fc_handler[].h");
|
|
fifo_client_unlock ();
|
|
if (!listen_client ())
|
|
debug_printf ("failed to start lct, %E");
|
|
}
|
|
}
|
|
|
|
void
|
|
fhandler_fifo::fixup_after_exec ()
|
|
{
|
|
fhandler_base::fixup_after_exec ();
|
|
if (reader && !close_on_exec ())
|
|
{
|
|
/* Make sure the child starts unlocked. */
|
|
fifo_client_unlock ();
|
|
|
|
if (!listen_client ())
|
|
debug_printf ("failed to start lct, %E");
|
|
}
|
|
}
|
|
|
|
void
|
|
fhandler_fifo::set_close_on_exec (bool val)
|
|
{
|
|
fhandler_base::set_close_on_exec (val);
|
|
set_no_inheritance (read_ready, val);
|
|
set_no_inheritance (write_ready, val);
|
|
set_no_inheritance (writer_opening, val);
|
|
fifo_client_lock ();
|
|
for (int i = 0; i < nhandlers; i++)
|
|
set_no_inheritance (fc_handler[i].h, val);
|
|
fifo_client_unlock ();
|
|
}
|