support . and .. search in find_entry, add init_entry for fake root

include/direntry.h

@@ -33,6 +33,8 @@ typedef struct treeNode {
     FileNode *self_info; //self fileNode infromation
 } TreeNode;
 
+/*for root*/
+TreeNode *fischl_init_entry(int new_inode_number, const char *fileName, INode *new_inode);
 /*root directory have its own initialization, so parent wont be NULL*/
 int fischl_add_entry(TreeNode *parent, int new_inode_number, const char *fileName, INode *new_inode);
 /*if want to use dir mode use the subdirectory treeNode pointer */

lib/direntry.cpp

@@ -127,6 +127,20 @@ void freeTree(TreeNode *node) {
 /*********************************Direntry operation******************************************
 
 ********************************************************************************************/
+//for fake root (mount point)
+TreeNode *fischl_init_entry(int new_inode_number, const char *fileName, INode *new_inode) {
+    TreeNode *newDir = (TreeNode *)malloc(sizeof(TreeNode));
+    newDir->dirName = strdup(fileName);
+    newDir->contents = createHashTable(20);//hashSize define 20
+    newDir->parent = newDir;
+    FileNode *newFile = (FileNode *)malloc(sizeof(FileNode));
+    newFile->name = strdup(fileName);
+    newFile->inode_number = new_inode_number;
+    newFile->permissions = new_inode->permissions;
+    newDir->self_info = newFile;
+    return newDir;
+}
+
 int fischl_add_entry(TreeNode *parent, int new_inode_number, const char *fileName, INode *new_inode){
     char *Name = strdup(fileName);
     TreeNode *newDir = NULL;
@@ -156,6 +170,17 @@ FileNode *fischl_find_entry(TreeNode *root, const char *path){
     FileNode *file = NULL;
 
     while (segment != NULL && current != NULL) {
+        if (strcmp(segment, "..") == 0) {
+            // Move up to the parent directory
+            current = current->parent;
+            if (current == NULL) {
+                // If there's no parent, we've reached the top of the tree, but root itself is same
+                break;
+            }
+        } else if (strcmp(segment, ".") == 0) {
+            // Stay in the current directory (no action needed)
+        } 
+        else{
             file = lookupHash(current->contents, segment);
             if (file != NULL && file->subdirectory == NULL) {
                 free(pathCopy);
@@ -163,10 +188,16 @@ FileNode *fischl_find_entry(TreeNode *root, const char *path){
                 //return current; return filenode
             }
             current = file ? file->subdirectory : NULL;
+        }
         segment = strtok(NULL, "/");
     }
 
     free(pathCopy);
-    return file; // NULL if not found
+
-    //return current; return filenode
+    if (current != NULL && file == NULL) {
+        // If we've stopped at a directory and not a file, return the directory's self info
+        return current->self_info;
+    }
+
+    return file; // NULL if not found
 }

test/dir_API.cpp

@@ -12,19 +12,25 @@
 #include "direntry.h"
 
 int main() {
-    TreeNode *root = createDirectory("/", NULL, 20);
+    //Init fake root directory
+    INode inode_root;
+    u_int64_t file_permissions = 0;
+    inode_root.permissions = file_permissions | S_IFDIR;
+    TreeNode *root = fischl_init_entry(0, "/", &inode_root);//0 is inode number assigned by inode_allocate()
+    //add file or dir under fake root
     INode inode_file1;
     fischl_add_entry(root, 2, "file1",&inode_file1);
     //I will put this function in create_new_inode function, there will inode number(2) when inode_allocate
     INode inode_dir1;
     //permission is necessary there to create treeNode or not
-    u_int64_t ddd_permissions = 0;
+    file_permissions = 0;
-    inode_dir1.permissions = ddd_permissions | S_IFDIR;
+    inode_dir1.permissions = file_permissions | S_IFDIR;
     fischl_add_entry(root, 3, "dir1",&inode_dir1);
     //find dir file (from root directory view, root contains dir1/ subdirectory)
     FileNode *get_dir1 = fischl_find_entry(root,"/dir1/");
     if(get_dir1 == NULL){
         printf("No dir1 under %s\n",root->dirName);
+        freeTree(root);
         return -1;
     }else{
         fprintf(stderr,"[%s ,%d]",__func__,__LINE__);
@@ -54,6 +60,7 @@ int main() {
     get_file2 = fischl_find_entry(root,"/dir1/file2");
     if(get_file2 == NULL){
         printf("No dir1 under dir1\n");
+        freeTree(root);
         return -1;
     }else{
         fprintf(stderr,"[%s ,%d]",__func__,__LINE__);
@@ -63,6 +70,7 @@ int main() {
     get_file2 = fischl_find_entry(get_dir1->subdirectory,"/file2");
     if(get_file2 == NULL){
         printf("No dir1 under %s\n",get_dir1->subdirectory->dirName);
+        freeTree(root);
         return -1;
     }else{
         fprintf(stderr,"[%s ,%d]",__func__,__LINE__);
@@ -80,10 +88,21 @@ int main() {
     get_file3 = fischl_find_entry(get_dir1_tree,"/file3");
     if(get_file3 == NULL){
         printf("No dir1 under %s\n",get_dir1_tree->dirName);
+        freeTree(root);
         return -1;
     }else{
         printf(" %s under %s\n",get_file3->name,get_dir1_tree->dirName);
     }
+    FileNode *get_file1 = NULL;//under root
+    //use .. to find
+    get_file1 = fischl_find_entry(get_dir1_tree,"../file1");
+    if(get_file1 == NULL){
+        printf("No file1\n");
+        freeTree(root);
+        return -1;
+    }else{
+        printf(" %s under root(..)\n",get_file1->name);
+    }
     // Cleanup
     freeTree(root);