Implement sys$chdir() and teach sh+ls to cd around and browse different dirs.

VirtualFileSystem/FileHandle.cpp

@@ -128,6 +128,11 @@ ByteBuffer FileHandle::readEntireFile()
     return m_vnode->fileSystem()->readEntireInode(m_vnode->inode);
 }
 
+bool FileHandle::isDirectory() const
+{
+    return m_vnode->metadata().isDirectory();
+}
+
 ssize_t FileHandle::get_dir_entries(byte* buffer, size_t size)
 {
     Locker locker(VirtualFileSystem::lock());

VirtualFileSystem/FileHandle.h

@@ -20,6 +20,10 @@ public:
 
     String absolutePath() const;
 
+    bool isDirectory() const;
+
+    VirtualFileSystem::Node* vnode() { return m_vnode.ptr(); }
+
 #ifdef SERENITY
     int fd() const { return m_fd; }
     void setFD(int fd) { m_fd = fd; }

VirtualFileSystem/VirtualFileSystem.cpp

@@ -168,9 +168,9 @@ void VirtualFileSystem::freeNode(Node* node)
     m_nodeFreeList.append(move(node));
 }
 
-bool VirtualFileSystem::isDirectory(const String& path)
+bool VirtualFileSystem::isDirectory(const String& path, Node* base)
 {
-    auto inode = resolvePath(path);
+    auto inode = resolvePath(path, base);
     if (!inode.isValid())
         return false;
 
@@ -355,11 +355,11 @@ bool VirtualFileSystem::touch(const String& path)
     return inode.fileSystem()->setModificationTime(inode, ktime(nullptr));
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::open(const String& path)
+OwnPtr<FileHandle> VirtualFileSystem::open(const String& path, Node* base)
 {
     Locker locker(VirtualFileSystem::lock());
 
-    auto inode = resolvePath(path);
+    auto inode = resolvePath(path, base);
     if (!inode.isValid())
         return nullptr;
     auto vnode = getOrCreateNode(inode);
@@ -368,7 +368,7 @@ OwnPtr<FileHandle> VirtualFileSystem::open(const String& path)
     return make<FileHandle>(move(vnode));
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::create(const String& path)
+OwnPtr<FileHandle> VirtualFileSystem::create(const String& path, Node* base)
 {
     Locker locker(VirtualFileSystem::lock());
 
@@ -378,7 +378,7 @@ OwnPtr<FileHandle> VirtualFileSystem::create(const String& path)
     return nullptr;
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::mkdir(const String& path)
+OwnPtr<FileHandle> VirtualFileSystem::mkdir(const String& path, Node* base)
 {
     Locker locker(VirtualFileSystem::lock());
 
@@ -398,10 +398,18 @@ InodeIdentifier VirtualFileSystem::resolveSymbolicLink(const String& basePath, I
     return resolvePath(buf);
 }
 
-InodeIdentifier VirtualFileSystem::resolvePath(const String& path)
+InodeIdentifier VirtualFileSystem::resolvePath(const String& path, Node* base)
 {
+    if (path.isEmpty())
+        return { };
+
     auto parts = path.split('/');
-    InodeIdentifier inode = m_rootNode->inode;
+    InodeIdentifier inode;
+
+    if (path[0] == '/')
+        inode = m_rootNode->inode;
+    else
+        inode = base ? base->inode : m_rootNode->inode;
 
     for (unsigned i = 0; i < parts.size(); ++i) {
         auto& part = parts[i];

VirtualFileSystem/VirtualFileSystem.h

@@ -51,7 +51,7 @@ public:
     VirtualFileSystem();
     ~VirtualFileSystem();
 
-    bool isDirectory(const String& path);
+    bool isDirectory(const String& path, Node* base = nullptr);
     void listDirectory(const String& path);
     void listDirectoryRecursively(const String& path);
 
@@ -64,9 +64,9 @@ public:
     bool mountRoot(RetainPtr<FileSystem>&&);
     bool mount(RetainPtr<FileSystem>&&, const String& path);
 
-    OwnPtr<FileHandle> open(const String& path);
-    OwnPtr<FileHandle> create(const String& path);
-    OwnPtr<FileHandle> mkdir(const String& path);
+    OwnPtr<FileHandle> open(const String& path, Node* base = nullptr);
+    OwnPtr<FileHandle> create(const String& path, Node* base = nullptr);
+    OwnPtr<FileHandle> mkdir(const String& path, Node* base = nullptr);
 
     bool isRoot(InodeIdentifier) const;
 
@@ -79,7 +79,7 @@ private:
 
     void enumerateDirectoryInode(InodeIdentifier, Function<bool(const FileSystem::DirectoryEntry&)>);
     String absolutePath(InodeIdentifier);
-    InodeIdentifier resolvePath(const String& path);
+    InodeIdentifier resolvePath(const String& path, Node* base = nullptr);
     InodeIdentifier resolveSymbolicLink(const String& basePath, InodeIdentifier symlinkInode);
 
     RetainPtr<Node> allocateNode();