diff options
Diffstat (limited to 'winsup/cygwin/pipe.cc')
| -rw-r--r-- | winsup/cygwin/pipe.cc | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/winsup/cygwin/pipe.cc b/winsup/cygwin/pipe.cc new file mode 100644 index 00000000000..82313c492f1 --- /dev/null +++ b/winsup/cygwin/pipe.cc @@ -0,0 +1,323 @@ +/* pipe.cc: pipe for Cygwin. + + Copyright 1996, 1998, 1999, 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. */ + +/* FIXME: Should this really be fhandler_pipe.cc? */ + +#include "winsup.h" +#include <unistd.h> +#include <sys/socket.h> +#include "cygerrno.h" +#include "security.h" +#include "path.h" +#include "fhandler.h" +#include "dtable.h" +#include "cygheap.h" +#include "thread.h" +#include "pinfo.h" +#include "cygthread.h" + +static unsigned pipecount; +static const NO_COPY char pipeid_fmt[] = "stupid_pipe.%u.%u"; + +fhandler_pipe::fhandler_pipe () + : fhandler_base (), guard (NULL), broken_pipe (false), writepipe_exists(0), + orig_pid (0), id (0) +{ +} + +_off64_t +fhandler_pipe::lseek (_off64_t offset, int whence) +{ + debug_printf ("(%d, %d)", offset, whence); + set_errno (ESPIPE); + return -1; +} + +void +fhandler_pipe::set_close_on_exec (int val) +{ + fhandler_base::set_close_on_exec (val); + if (guard) + set_inheritance (guard, val); + if (writepipe_exists) + set_inheritance (writepipe_exists, val); +} + +struct pipeargs +{ + fhandler_base *fh; + void *ptr; + size_t *len; +}; + +static DWORD WINAPI +read_pipe (void *arg) +{ + pipeargs *pi = (pipeargs *) arg; + pi->fh->fhandler_base::read (pi->ptr, *pi->len); + return 0; +} + +void __stdcall +fhandler_pipe::read (void *in_ptr, size_t& in_len) +{ + if (broken_pipe) + in_len = 0; + else + { + pipeargs pi = {dynamic_cast<fhandler_base *>(this), in_ptr, &in_len}; + ResetEvent (read_state); + cygthread *th = new cygthread (read_pipe, &pi, "read_pipe"); + if (th->detach (read_state) && !in_len) + in_len = (size_t) -1; /* received a signal */ + } + (void) ReleaseMutex (guard); + return; +} + +int +fhandler_pipe::close () +{ + if (guard) + CloseHandle (guard); + if (writepipe_exists) + CloseHandle (writepipe_exists); +#ifndef NEWVFORK + if (read_state) +#else + // FIXME is this vfork_cleanup test right? Is it responsible for some of + // the strange pipe behavior that has been reported in the cygwin mailing + // list? + if (read_state && !cygheap->fdtab.in_vfork_cleanup ()) +#endif + ForceCloseHandle (read_state); + if (get_handle ()) + { + CloseHandle (get_handle ()); + set_io_handle (NULL); + } + return 0; +} + +bool +fhandler_pipe::hit_eof () +{ + char buf[80]; + HANDLE ev; + if (broken_pipe) + return 1; + if (!orig_pid) + return false; + __small_sprintf (buf, pipeid_fmt, orig_pid, id); + if ((ev = OpenEvent (EVENT_ALL_ACCESS, FALSE, buf))) + CloseHandle (ev); + debug_printf ("%s %p", buf, ev); + return ev == NULL; +} + +void +fhandler_pipe::fixup_after_exec (HANDLE parent) +{ + if (read_state) + { + read_state = CreateEvent (&sec_none_nih, FALSE, FALSE, NULL); + ProtectHandle (read_state); + } +} + +void +fhandler_pipe::fixup_after_fork (HANDLE parent) +{ + fhandler_base::fixup_after_fork (parent); + if (guard) + fork_fixup (parent, guard, "guard"); + if (writepipe_exists) + fork_fixup (parent, writepipe_exists, "guard"); + fixup_after_exec (parent); +} + +int +fhandler_pipe::dup (fhandler_base *child) +{ + int res = -1; + fhandler_pipe *ftp = (fhandler_pipe *) child; + ftp->guard = ftp->writepipe_exists = ftp->read_state = NULL; + + if (get_handle ()) + { + res = fhandler_base::dup (child); + if (res) + goto err; + } + + /* FIXME: This leaks handles in the failing condition */ + if (guard == NULL) + ftp->guard = NULL; + else if (!DuplicateHandle (hMainProc, guard, hMainProc, &ftp->guard, 0, 1, + DUPLICATE_SAME_ACCESS)) + { + debug_printf ("couldn't duplicate guard %p, %E", guard); + goto err; + } + + if (writepipe_exists == NULL) + ftp->writepipe_exists = NULL; + else if (!DuplicateHandle (hMainProc, writepipe_exists, hMainProc, + &ftp->writepipe_exists, 0, 1, + DUPLICATE_SAME_ACCESS)) + { + debug_printf ("couldn't duplicate writepipe_exists %p, %E", writepipe_exists); + goto err; + } + + if (read_state == NULL) + ftp->read_state = NULL; + else if (!DuplicateHandle (hMainProc, read_state, hMainProc, + &ftp->read_state, 0, 1, + DUPLICATE_SAME_ACCESS)) + { + debug_printf ("couldn't duplicate read_state %p, %E", writepipe_exists); + goto err; + } + + res = 0; + goto out; + +err: + if (!ftp->guard) + CloseHandle (ftp->guard); + if (!ftp->writepipe_exists) + CloseHandle (ftp->writepipe_exists); + if (!ftp->read_state) + CloseHandle (ftp->read_state); + goto leave; + +out: + ftp->id = id; + ftp->orig_pid = orig_pid; + VerifyHandle (ftp->guard); + VerifyHandle (ftp->writepipe_exists); + VerifyHandle (ftp->read_state); + +leave: + debug_printf ("res %d", res); + return res; +} + +int +fhandler_pipe::create (fhandler_pipe *fhs[2], unsigned psize, int mode, bool fifo) +{ + HANDLE r, w; + SECURITY_ATTRIBUTES *sa = (mode & O_NOINHERIT) ? &sec_none_nih : &sec_none; + int res = -1; + + if (!CreatePipe (&r, &w, sa, psize)) + __seterrno (); + else + { + fhs[0] = (fhandler_pipe *) build_fh_dev (*piper_dev); + fhs[1] = (fhandler_pipe *) build_fh_dev (*pipew_dev); + + int binmode = mode & O_TEXT ?: O_BINARY; + fhs[0]->init (r, GENERIC_READ, binmode); + fhs[1]->init (w, GENERIC_WRITE, binmode); + if (mode & O_NOINHERIT) + { + fhs[0]->set_close_on_exec_flag (1); + fhs[1]->set_close_on_exec_flag (1); + } + + fhs[0]->read_state = CreateEvent (&sec_none_nih, FALSE, FALSE, NULL); + fhs[0]->set_need_fork_fixup (); + ProtectHandle1 (fhs[0]->read_state, read_state); + + res = 0; + fhs[0]->create_guard (sa); + if (wincap.has_unreliable_pipes ()) + { + char buf[80]; + int count = pipecount++; /* FIXME: Should this be InterlockedIncrement? */ + __small_sprintf (buf, pipeid_fmt, myself->pid, count); + fhs[1]->writepipe_exists = CreateEvent (sa, TRUE, FALSE, buf); + fhs[0]->orig_pid = myself->pid; + fhs[0]->id = count; + } + } + + syscall_printf ("%d = ([%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; +} + +extern "C" int +pipe (int filedes[2]) +{ + extern DWORD binmode; + fhandler_pipe *fhs[2]; + int res = fhandler_pipe::create (fhs, 16384, (!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]->set_r_no_interrupt (1); + fdin = fhs[0]; + fdout = fhs[1]; + filedes[0] = fdin; + filedes[1] = fdout; + } + + return res; +} |