Boot loader BFS now has symbolic link support.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@7516 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kernel/boot/loader/file_systems/bfs/Directory.cpp

@@ -1,16 +1,23 @@
 /*
-** Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
+** Copyright 2003-2004, Axel Dörfler, [email protected]. All rights reserved.
 ** Distributed under the terms of the OpenBeOS License.
 */
 
 
 #include "Directory.h"
 #include "File.h"
+#include "Link.h"
 
 #include <StorageDefs.h>
+#include <KernelExport.h>
 #include <util/kernel_cpp.h>
 
 #include <string.h>
+#include <unistd.h>
+
+
+// temp. private VFS API
+extern Node *get_node_from(int fd);
 
 
 namespace BFS {
@@ -82,9 +89,25 @@ Directory::Lookup(const char *name, bool traverseLinks)
 		return NULL;
 
 	Node *node = Stream::NodeFactory(fStream.GetVolume(), id);
-	if (node->Type() == S_IFLNK) {
-		// ToDo: support links!
+
+	if (S_ISLNK(node->Type())) {
+		// the node is a symbolic link, so we have to resolve the path
+		char linkPath[B_PATH_NAME_LENGTH];
+		((Link *)node)->ReadLink(linkPath, sizeof(linkPath));
+
 		delete node;
+			// we don't need this one anymore
+
+		int fd = open_from(this, linkPath, O_RDONLY);
+		if (fd >= 0) {
+			node = get_node_from(fd);
+			if (node != NULL)
+				node->Acquire();
+
+			close(fd);
+			return node;
+		}
+
 		return NULL;
 	}
 

src/kernel/boot/loader/file_systems/bfs/File.h

@@ -1,5 +1,5 @@
 /*
-** Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
+** Copyright 2003-2004, Axel Dörfler, [email protected]. All rights reserved.
 ** Distributed under the terms of the OpenBeOS License.
 */
 #ifndef FILE_H
@@ -30,7 +30,7 @@ class File : public Node {
 		virtual int32 Type() const;
 		virtual off_t Size() const;
 
-	private:
+	protected:
 		Stream		fStream;
 };
 

src/kernel/boot/loader/file_systems/bfs/Jamfile

@@ -10,6 +10,7 @@ KernelStaticLibrary boot_bfs :
 	bfs.cpp
 	Directory.cpp
 	File.cpp
+	Link.cpp
 	Stream.cpp
 	BPlusTree.cpp
 	;

src/kernel/boot/loader/file_systems/bfs/Link.cpp

@@ -0,0 +1,66 @@
+/*
+** Copyright 2004, Axel Dörfler, [email protected]. All rights reserved.
+** Distributed under the terms of the OpenBeOS License.
+*/
+
+
+#include "Link.h"
+
+#include <util/kernel_cpp.h>
+
+
+namespace BFS {
+
+Link::Link(Volume &volume, block_run run)
+	: File(volume, run)
+{
+}
+
+
+Link::Link(Volume &volume, off_t id)
+	: File(volume, id)
+{
+}
+
+
+Link::Link(const Stream &stream)
+	: File(stream)
+{
+}
+
+
+status_t
+Link::InitCheck()
+{
+	return fStream.InitCheck();
+}
+
+
+status_t
+Link::ReadLink(char *buffer, size_t bufferSize)
+{
+	return fStream.ReadLink(buffer, bufferSize);
+}
+
+
+ssize_t
+Link::ReadAt(void *cookie, off_t pos, void *buffer, size_t bufferSize)
+{
+	return B_NOT_ALLOWED;
+}
+
+
+ssize_t
+Link::WriteAt(void *cookie, off_t pos, const void *buffer, size_t bufferSize)
+{
+	return B_NOT_ALLOWED;
+}
+
+
+int32
+Link::Type() const
+{
+	return S_IFLNK;
+}
+
+}	// namespace BFS

src/kernel/boot/loader/file_systems/bfs/Link.h

@@ -0,0 +1,33 @@
+/*
+** Copyright 2004, Axel Dörfler, [email protected]. All rights reserved.
+** Distributed under the terms of the OpenBeOS License.
+*/
+#ifndef LINK_H
+#define LINK_H
+
+
+#include <boot/vfs.h>
+
+#include "File.h"
+
+
+namespace BFS {
+
+class Link : public File {
+	public:
+		Link(Volume &volume, block_run run);
+		Link(Volume &volume, off_t id);
+		Link(const Stream &stream);
+
+		status_t InitCheck();
+		status_t ReadLink(char *buffer, size_t bufferSize);
+
+		virtual ssize_t ReadAt(void *cookie, off_t pos, void *buffer, size_t bufferSize);
+		virtual ssize_t WriteAt(void *cookie, off_t pos, const void *buffer, size_t bufferSize);
+
+		virtual int32 Type() const;
+};
+
+}	// namespace BFS
+
+#endif	/* FILE_H */

src/kernel/boot/loader/file_systems/bfs/Stream.cpp

@@ -1,6 +1,6 @@
 /* Stream - inode stream access functions
 **
-** Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
+** Copyright 2003-2004, Axel Dörfler, [email protected]. All rights reserved.
 ** Distributed under the terms of the OpenBeOS License.
 */
 
@@ -8,6 +8,7 @@
 #include "Stream.h"
 #include "Directory.h"
 #include "File.h"
+#include "Link.h"
 
 #include <util/kernel_cpp.h>
 
@@ -169,6 +170,21 @@ Stream::GetName(char *name, size_t size) const
 }
 
 
+status_t 
+Stream::ReadLink(char *buffer, size_t bufferSize)
+{
+	// link in the stream
+
+	if (Flags() & INODE_LONG_SYMLINK)
+		return ReadAt(0, (uint8 *)buffer, &bufferSize);
+
+	// link in the inode
+
+	strlcpy(buffer, short_symlink, bufferSize);
+	return B_OK;
+}
+
+
 status_t
 Stream::FindBlockRun(off_t pos, block_run &run, off_t &offset)
 {
@@ -389,6 +405,9 @@ Stream::NodeFactory(Volume &volume, off_t id)
 	if (stream.IsContainer())
 		return new Directory(stream);
 
+	if (stream.IsSymlink())
+		return new Link(stream);
+
 	return new File(stream);
 }
 

src/kernel/boot/loader/file_systems/bfs/Stream.h

@@ -1,6 +1,6 @@
 /* Stream - inode stream access functions
 **
-** Copyright 2003, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+** Copyright 2003-2004, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
 ** Distributed under the terms of the OpenBeOS License.
 */
 #ifndef STREAM_H
@@ -31,7 +31,10 @@ class Stream : public bfs_inode {
 		status_t GetName(char *name, size_t size) const;
 		off_t Size() const { return data.Size(); }
 		off_t ID() const { return fVolume.ToVnode(inode_num); }
+		status_t ReadLink(char *buffer, size_t bufferSize);
+
 		bool IsContainer() const { return Mode() & (S_IFDIR | S_INDEX_DIR | S_ATTR_DIR); }
+		bool IsSymlink() const { return S_ISLNK(Mode()); }
 
 		static Node *NodeFactory(Volume &volume, off_t id);