[PATCH 4/5] Windows: simplify the pipe(2) implementation
- From
Johannes Sixt <j6t@kdbg.org>
- Date
- Jan 7, 2010, 21:55 UTC
- Message-ID
- <7fc9ba13ae1495001ec8fbb4df9541975652dcea.1262895937.git.j6t@kdbg.org>
- In-Reply-To
- <cover.1262895936.git.j6t@kdbg.org>
Our implementation of pipe() must create non-inheritable handles for the reason that when a child process is started, there is no opportunity to close the unneeded pipe ends in the child (on POSIX this is done between fork() and exec()).
Previously, we used the _pipe() function provided by Microsoft's C runtime (which creates inheritable handles) and then turned the handles into non-inheritable handles using the DuplicateHandle() API.
Simplify the procedure by using the CreatePipe() API, which can create non-inheritable handles right from the beginning.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> --- compat/mingw.c | 37 ++++++++----------------------------- 1 files changed, 8 insertions(+), 29 deletions(-)
diff --git a/compat/mingw.c b/compat/mingw.c index dfb1f05..9f4fab3 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -299,46 +299,25 @@ int gettimeofday(struct timeval *tv, void *tz) int pipe(int filedes[2]) { - int fd; - HANDLE h[2], parent; - - if (_pipe(filedes, 8192, 0) < 0) - return -1; + HANDLE h[2]; - parent = GetCurrentProcess(); - - if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[0]), - parent, &h[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) { - close(filedes[0]); - close(filedes[1]); - return -1; - } - if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[1]), - parent, &h[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) { - close(filedes[0]); - close(filedes[1]); - CloseHandle(h[0]); + /* this creates non-inheritable handles */ + if (!CreatePipe(&h[0], &h[1], NULL, 8192)) { + errno = err_win_to_posix(GetLastError()); return -1; } - fd = _open_osfhandle((int)h[0], O_NOINHERIT); - if (fd < 0) { - close(filedes[0]); - close(filedes[1]); + filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT); + if (filedes[0] < 0) { CloseHandle(h[0]); CloseHandle(h[1]); return -1; } - close(filedes[0]); - filedes[0] = fd; - fd = _open_osfhandle((int)h[1], O_NOINHERIT); - if (fd < 0) { + filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT); + if (filedes[0] < 0) { close(filedes[0]); - close(filedes[1]); CloseHandle(h[1]); return -1; } - close(filedes[1]); - filedes[1] = fd; return 0; }
-- 1.6.6.115.gd1ab3