file_systems/fs_ops_support: Add open_mode_to_access.

This is duplicated across multiple filesystems, and could probably be
used in more still.

Adjusted only BFS, EXT2, and NTFS in this commit, as they are the ones
which make use of fs_ops_support.h already and thus need to be modified
to avoid duplicate-definition errors.

Also tweak next_dirent to support being built under fs_shell.
(Possibly we should define ASSERT there, though?)

headers/private/file_systems/fs_ops_support.h

@@ -14,6 +14,22 @@
 #endif
 
 
+/*!	Converts a given open mode (e.g. O_RDONLY) into access modes (e.g. R_OK).
+ */
+static inline int
+open_mode_to_access(int openMode)
+{
+	openMode &= O_RWMASK;
+	if (openMode == O_RDONLY)
+		return R_OK;
+	if (openMode == O_WRONLY)
+		return W_OK;
+	if (openMode == O_RDWR)
+		return R_OK | W_OK;
+	return 0;
+}
+
+
 /*! Computes and assigns `dirent->d_reclen`, adjusts `bufferRemaining` accordingly,
  * and either advances to the next buffer, or returns NULL if no space remains.
  */
@@ -21,7 +37,9 @@ static inline struct dirent*
 next_dirent(struct dirent* dirent, size_t nameLength, size_t& bufferRemaining)
 {
 	const size_t reclen = offsetof(struct dirent, d_name) + nameLength + 1;
+#ifdef ASSERT
 	ASSERT(reclen <= bufferRemaining);
+#endif
 	dirent->d_reclen = reclen;
 
 	const size_t roundedReclen = ROUNDUP(reclen, alignof(struct dirent));

src/add-ons/kernel/file_systems/bfs/Utility.h

@@ -8,6 +8,8 @@
 
 #include "system_dependencies.h"
 
+#include <file_systems/fs_ops_support.h>
+
 #include "bfs.h"
 
 
@@ -131,20 +133,4 @@ is_directory(int mode)
 }
 
 
-/*!	Converts the open mode, the open flags given to bfs_open(), into
-	access modes, e.g. since O_RDONLY requires read access to the
-	file, it will be converted to R_OK.
-*/
-inline int
-open_mode_to_access(int openMode)
-{
-	openMode &= O_RWMASK;
-	if (openMode == O_RDONLY)
-		return R_OK;
-	if (openMode == O_WRONLY)
-		return W_OK;
-
-	return R_OK | W_OK;
-}
-
 #endif	// UTILITY_H

src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp

@@ -19,8 +19,6 @@
 #include "bfs_control.h"
 #include "bfs_disk_system.h"
 
-#include <file_systems/fs_ops_support.h>
-
 // TODO: temporary solution as long as there is no public I/O requests API
 #ifndef FS_SHELL
 #	include <io_requests.h>

src/add-ons/kernel/file_systems/ext2/Utility.h

@@ -7,6 +7,9 @@
 
 #include "ext2.h"
 
+#include <file_systems/fs_ops_support.h>
+
+
 enum inode_type {
 	S_DIRECTORY		= S_IFDIR,
 	S_FILE			= S_IFREG,
@@ -20,20 +23,4 @@ enum inode_type {
 };
 
 
-/*!	Converts the open mode, the open flags given to bfs_open(), into
-	access modes, e.g. since O_RDONLY requires read access to the
-	file, it will be converted to R_OK.
-*/
-inline int
-open_mode_to_access(int openMode)
-{
-	openMode &= O_RWMASK;
-	if (openMode == O_RDONLY)
-		return R_OK;
-	if (openMode == O_WRONLY)
-		return W_OK;
-
-	return R_OK | W_OK;
-}
-
 #endif	// UTILITY_H

src/add-ons/kernel/file_systems/ext2/kernel_interface.cpp

@@ -12,7 +12,6 @@
 #include <string.h>
 
 #include <AutoDeleter.h>
-#include <file_systems/fs_ops_support.h>
 #include <fs_cache.h>
 #include <fs_info.h>
 #include <io_requests.h>

src/add-ons/kernel/file_systems/ntfs/kernel_interface.cpp

@@ -713,19 +713,6 @@ fs_write_stat(fs_volume* _volume, fs_vnode* _node, const struct stat* stat, uint
 }
 
 
-static inline int
-open_mode_to_access(int openMode)
-{
-	if ((openMode & O_RWMASK) == O_RDONLY)
-		return R_OK;
-	if ((openMode & O_RWMASK) == O_WRONLY)
-		return W_OK;
-	if ((openMode & O_RWMASK) == O_RDWR)
-		return R_OK | W_OK;
-	return 0;
-}
-
-
 static status_t
 fs_generic_create(fs_volume* _volume, vnode* directory, const char* name, int mode,
 	ino_t* _inode)