fs, kernel(HeFS): Implement `hefs_get_index_node` for tree traversal.

Signed-off-by: Amlal El Mahrouss <amlal@nekernel.org>

3 files changed, 145 insertions, 2 deletions

diff --git a/dev/kernel/src/FS/Ext2.cc b/dev/kernel/src/FS/Ext2.cc
index 5de8c842..8331f506 100644
--- a/dev/kernel/src/FS/Ext2.cc
+++ b/dev/kernel/src/FS/Ext2.cc
@@ -8,7 +8,6 @@
 
 #include <modules/AHCI/AHCI.h>
 #include <modules/ATA/ATA.h>
-#include <modules/Flash/Flash.h>
 #include <FSKit/Ext2.h>
 #include <KernelKit/KPC.h>
 #include <NewKit/Crc32.h>
diff --git a/dev/kernel/src/FS/HeFS.cc b/dev/kernel/src/FS/HeFS.cc
index 1c82548c..0344309e 100644
--- a/dev/kernel/src/FS/HeFS.cc
+++ b/dev/kernel/src/FS/HeFS.cc
@@ -8,7 +8,6 @@
 
 #include <modules/AHCI/AHCI.h>
 #include <modules/ATA/ATA.h>
-#include <modules/Flash/Flash.h>
 #include <FSKit/HeFS.h>
 #include <KernelKit/KPC.h>
 #include <NewKit/Crc32.h>
@@ -19,4 +18,137 @@
 #include <KernelKit/ProcessScheduler.h>
 #include <KernelKit/User.h>
 
+namespace Kernel
+{
+	namespace Detail
+	{
+		STATIC HeFS_INDEX_NODE* hefs_get_index_node(HeFS_BOOT_NODE* root, DriveTrait* mnt, const Utf16Char* dir_name, const Utf16Char* file_name, UInt8 kind) noexcept
+		{
+			if (root)
+			{
+				HeFS_INDEX_NODE*		   node = new HeFS_INDEX_NODE();
+				HeFS_INDEX_NODE_DIRECTORY* dir	= new HeFS_INDEX_NODE_DIRECTORY();
+
+				if (!node)
+				{
+					kout << "Error: Failed to allocate memory for index node.\r";
+					return nullptr;
+				}
+
+				auto start = root->fStartIND;
+				auto end   = root->fEndIND;
+
+				auto hop_watch = 0;
+
+				while (start != end)
+				{
+					if (hop_watch++ > 100)
+					{
+						kout << "Error: Hop watch exceeded.\r";
+						
+						break;
+					}
+
+					if (start == 0)
+					{
+						++hop_watch;
+						start = root->fStartIND;
+					}
+
+					mnt->fPacket.fPacketLba		= start;
+					mnt->fPacket.fPacketSize	= sizeof(HeFS_INDEX_NODE_DIRECTORY);
+					mnt->fPacket.fPacketContent = dir;
+
+					mnt->fInput(mnt->fPacket);
+
+					if (!mnt->fPacket.fPacketGood)
+					{
+						delete node;
+						delete dir;
+
+						err_global_get() = kErrorFileNotFound;
+
+
+						return nullptr;
+					}
+
+					if (dir->fKind == kHeFSFileKindDirectory)
+					{
+						if (KStringBuilder::Equals(dir_name, dir->fName))
+						{
+							for (SizeT inode_index = 0UL; inode_index < kHeFSBlockCount; ++inode_index)
+							{
+								if (dir->fIndexNodeStart[inode_index] != 0)
+								{
+									mnt->fPacket.fPacketLba		= dir->fIndexNodeStart[inode_index];
+									mnt->fPacket.fPacketSize	= sizeof(HeFS_INDEX_NODE);
+									mnt->fPacket.fPacketContent = node;
+
+									mnt->fInput(mnt->fPacket);
+
+									if (mnt->fPacket.fPacketGood)
+									{
+										if (KStringBuilder::Equals(file_name, node->fName) && node->fKind == kind)
+										{
+											delete dir;
+
+											return node;
+										}
+									}
+									else
+									{
+										break;
+									}
+								}
+								else if (dir->fIndexNodeEnd[inode_index] != 0)
+								{
+									mnt->fPacket.fPacketLba		= dir->fIndexNodeEnd[inode_index];
+									mnt->fPacket.fPacketSize	= sizeof(HeFS_INDEX_NODE);
+									mnt->fPacket.fPacketContent = node;
+
+									mnt->fInput(mnt->fPacket);
+
+									if (mnt->fPacket.fPacketGood)
+									{
+										if (KStringBuilder::Equals(file_name, node->fName) && node->fKind == kind)
+										{
+											delete dir;
+
+											return node;
+										}
+									}
+									else
+									{
+										break;
+									}
+								}
+							}
+						}
+					}
+
+					start = dir->fNext;
+
+					if (start == 0)
+						start = dir->fChild;
+
+					if (start == 0)
+						start = dir->fParent;
+				}
+
+				delete dir;
+				delete node;
+
+				dir	 = nullptr;
+				node = nullptr;
+			}
+
+			kout << "Error: Failed to find index node.\r";
+
+			err_global_get() = kErrorFileNotFound;
+
+			return nullptr;
+		}
+	} // namespace Detail
+} // namespace Kernel
+
 #endif // ifdef __FSKIT_INCLUDES_HeFS__
diff --git a/dev/kernel/src/KString.cc b/dev/kernel/src/KString.cc
index c1a8db65..2f81ad3d 100644
--- a/dev/kernel/src/KString.cc
+++ b/dev/kernel/src/KString.cc
@@ -143,6 +143,18 @@ namespace Kernel
 		return true;
 	}
 
+	/// @note This is unsafe!!!
+	bool KStringBuilder::Equals(const Utf16Char* lhs, const Utf16Char* rhs)
+	{
+		for (Size index = 0; index[rhs] != 0; ++index)
+		{
+			if (rhs[index] != lhs[index])
+				return false;
+		}
+
+		return true;
+	}
+
 	bool KStringBuilder::Equals(const WideChar* lhs, const WideChar* rhs)
 	{
 		for (Size index = 0; rhs[index] != 0; ++index)