Restructured and rewritten entire codebase

storage/ref_node.cpp

@@ -0,0 +1,158 @@
+/*
+	This file is part of Fennix Kernel.
+
+	Fennix Kernel is free software: you can redistribute it and/or
+	modify it under the terms of the GNU General Public License as
+	published by the Free Software Foundation, either version 3 of
+	the License, or (at your option) any later version.
+
+	Fennix Kernel is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <filesystem.hpp>
+
+#ifdef DEBUG
+const char *SeekStrings[] =
+	{"SEEK_SET",
+	 "SEEK_CUR",
+	 "SEEK_END"};
+#endif
+
+namespace vfs
+{
+	size_t RefNode::read(uint8_t *Buffer, size_t Size)
+	{
+		if (this->SymlinkTo)
+			return this->SymlinkTo->read(Buffer, Size);
+
+		return this->node->read(Buffer, Size, this->FileOffset.load());
+	}
+
+	size_t RefNode::write(uint8_t *Buffer, size_t Size)
+	{
+		if (this->SymlinkTo)
+			return this->SymlinkTo->write(Buffer, Size);
+
+		return this->node->write(Buffer, Size, this->FileOffset.load());
+	}
+
+	off_t RefNode::seek(off_t Offset, int Whence)
+	{
+		if (this->SymlinkTo)
+			return this->SymlinkTo->seek(Offset, Whence);
+
+		// debug("Current offset is %d", this->Offset.load());
+		switch (Whence)
+		{
+		case SEEK_SET:
+		{
+			if (Offset > this->FileSize)
+				return -EINVAL;
+
+			if (Offset < 0)
+			{
+				fixme("Negative offset %d is not implemented", Offset);
+				Offset = 0;
+			}
+
+			if (Offset > this->FileSize)
+			{
+				fixme("Offset %d is bigger than file size %d",
+					  Offset, this->FileSize);
+				Offset = this->FileSize;
+			}
+
+			this->FileOffset.store(Offset);
+			break;
+		}
+		case SEEK_CUR:
+		{
+			off_t NewOffset = off_t(this->FileOffset.load()) + Offset;
+			if (NewOffset > this->FileSize ||
+				NewOffset < 0)
+			{
+				return -EINVAL;
+			}
+
+			this->FileOffset.store(NewOffset);
+			break;
+		}
+		case SEEK_END:
+		{
+			off_t NewOffset = this->FileSize + Offset;
+			if (NewOffset > this->FileSize ||
+				NewOffset < 0)
+			{
+				return -EINVAL;
+			}
+
+			this->FileOffset.store(NewOffset);
+			break;
+		}
+		default:
+		{
+			error("Invalid whence!");
+			return -EINVAL;
+		}
+		}
+
+		off_t RetOffset = off_t(this->FileOffset.load());
+		// debug("( %d %ld %s[%d] ) -> %d",
+		// 	  Offset, this->Offset.load(),
+		// 	  SeekStrings[Whence], Whence,
+		// 	  RetOffset);
+		return RetOffset;
+	}
+
+	int RefNode::ioctl(unsigned long Request, void *Argp)
+	{
+		if (this->SymlinkTo)
+			return this->SymlinkTo->ioctl(Request, Argp);
+
+		return this->node->ioctl(Request, Argp);
+	}
+
+	RefNode::RefNode(Node *node)
+	{
+		this->node = node;
+		this->FileSize = node->Size;
+		if (this->node->Type == SYMLINK)
+		{
+			if (!this->node->SymlinkTarget)
+			{
+				this->node->SymlinkTarget =
+					node->vFS->GetNodeFromPath(this->node->Symlink);
+			}
+
+			if (!this->node->SymlinkTarget)
+			{
+				error("Symlink target %s not found!",
+					  this->node->Symlink);
+				return;
+			}
+
+			/* not standard but useful in kernel-space */
+			this->node->Size = this->node->SymlinkTarget->Size;
+			this->SymlinkTo = this->node->SymlinkTarget->CreateReference();
+		}
+
+		debug("Created reference node for %s [%#lx]",
+			  this->node->FullPath, (uintptr_t)this);
+	}
+
+	RefNode::~RefNode()
+	{
+		if (this->SymlinkTo)
+			this->node->SymlinkTarget->RemoveReference(this);
+		this->node->RemoveReference(this);
+
+		debug("Destroyed reference node for %s [%#lx]",
+			  this->node->FullPath, (uintptr_t)this);
+	}
+}