* Added _kern_create_pipe() syscall, creating a pipe as an entryless

FIFO. Reimplemented pipe() to use it.
* pipefs is no longer mounted. Will remove the superfluous code soon.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24823 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/syscalls.h

@@ -179,6 +179,7 @@ extern status_t		_kern_unlink(int fd, const char *path);
 extern status_t		_kern_rename(int oldDir, const char *oldpath, int newDir,
 						const char *newpath);
 extern status_t		_kern_create_fifo(const char *path, mode_t perms);
+extern status_t		_kern_create_pipe(int *fds);
 extern status_t		_kern_access(const char *path, int mode);
 extern ssize_t		_kern_select(int numfds, struct fd_set *readSet,
 						struct fd_set *writeSet, struct fd_set *errorSet,

headers/private/kernel/vfs.h

@@ -172,6 +172,7 @@ status_t _user_unlink(int fd, const char *path);
 status_t _user_rename(int oldFD, const char *oldpath, int newFD,
 			const char *newpath);
 status_t _user_create_fifo(const char *path, mode_t perms);
+status_t _user_create_pipe(int *fds);
 status_t _user_access(const char *path, int mode);
 ssize_t _user_select(int numfds, fd_set *readSet, fd_set *writeSet, fd_set *errorSet,
 			bigtime_t timeout, const sigset_t *sigMask);

src/system/kernel/fs/vfs.cpp

@@ -8186,6 +8186,60 @@ _user_create_fifo(const char *userPath, mode_t perms)
 }
 
 
+status_t
+_user_create_pipe(int *userFDs)
+{
+	// rootfs should support creating FIFOs, but let's be sure
+	if (!HAS_FS_CALL(sRoot, create_special_node))
+		return B_UNSUPPORTED;
+
+	// create the node	-- the FIFO sub node is set up automatically
+	fs_vnode superVnode;
+	ino_t nodeID;
+	status_t status = FS_CALL(sRoot, create_special_node, NULL, NULL,
+		S_IFIFO | S_IRUSR | S_IWUSR, 0, &superVnode, &nodeID);
+	if (status != B_OK)
+		return status;
+
+	// We've got one reference to the node and need another one.
+	struct vnode* vnode;
+	status = get_vnode(sRoot->mount->id, nodeID, &vnode, true, false);
+	if (status != B_OK) {
+		// that should not happen
+		dprintf("_user_create_pipe(): Failed to lookup vnode (%ld, %lld)\n",
+			sRoot->mount->id, sRoot->id);
+		return status;
+	}
+
+	// Everything looks good so far. Open two FDs for reading respectively
+	// writing.
+	int fds[2];
+	fds[0] = open_vnode(vnode, O_RDONLY, false);
+	fds[1] = open_vnode(vnode, O_WRONLY, false);
+
+	FDCloser closer0(fds[0], false);
+	FDCloser closer1(fds[1], false);
+
+	status = (fds[0] >= 0 ? (fds[1] >= 0 ? B_OK : fds[1]) : fds[0]);
+
+	// copy FDs to userland
+	if (status == B_OK) {
+		if (!IS_USER_ADDRESS(userFDs)
+			|| user_memcpy(userFDs, fds, sizeof(fds)) != B_OK) {
+			status = B_BAD_ADDRESS;
+		}
+	}
+
+	// keep FDs, if everything went fine
+	if (status == B_OK) {
+		closer0.Detach();
+		closer1.Detach();
+	}
+
+	return status;
+}
+
+
 status_t
 _user_access(const char *userPath, int mode)
 {

src/system/kernel/fs/vfs_boot.cpp

@@ -453,12 +453,6 @@ vfs_bootstrap_file_systems(void)
 	if (status < B_OK)
 		panic("error mounting devfs\n");
 
-	// bootstrap the pipefs
-	_kern_create_dir(-1, "/pipe", 0755);
-	status = _kern_mount("/pipe", NULL, "pipefs", 0, NULL, 0);
-	if (status < B_OK)
-		panic("error mounting pipefs\n");
-
 	// create directory for the boot volume
 	_kern_create_dir(-1, "/boot", 0755);
 

src/system/libroot/posix/unistd/pipe.c

@@ -1,34 +1,20 @@
 /* 
- * Copyright 2003-2007, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+ * Copyright 2008, Ingo Weinhold, ingo_weinhold@gmx.de. All rights reserved.
  * Distributed under the terms of the MIT License.
  */
 
-
-#include <OS.h>
-
+#include <errno.h>
 #include <unistd.h>
-#include <fcntl.h>
-#include <stdio.h>
+
+#include <syscalls.h>
 
 
 int
 pipe(int streams[2])
 {
-	bigtime_t timestamp = system_time();
-	char pipeName[64];
-	
-	while (system_time() <= timestamp)	// ensure we get an unused timestamp
-		;
-		
-	sprintf(pipeName, "/pipe/%03lx-%Ld", find_thread(NULL), system_time());
-
-	streams[0] = open(pipeName, O_CREAT | O_RDONLY, 0777);
-	if (streams[0] < 0)
-		return -1;
-
-	streams[1] = open(pipeName, O_WRONLY);
-	if (streams[1] < 0) {
-		close(streams[0]);
+	status_t error = _kern_create_pipe(streams);
+	if (error != B_OK) {
+		errno = error;
 		return -1;
 	}