lxfs: stub for parsing directory tree

fs/lxfs/src/dirtree.c

@@ -0,0 +1,58 @@
+/*
+ * luxOS - a unix-like operating system
+ * Omar Elghoul, 2024
+ * 
+ * lxfs: Driver for the lxfs file system
+ */
+
+#include <lxfs/lxfs.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+/* pathDepth(): helper function to calculate the depth of a path
+ * params: path - full qualified path
+ * returns: maximum depth of the path
+ */
+
+int pathDepth(const char *path) {
+    if(!path || !strlen(path) || strlen(path) == 1) return 0;
+
+    int c = 0;
+    for(int i = 0; i < strlen(path); i++) {
+        if(path[i] == '/') c++;
+    }
+
+    return c;
+}
+
+/* pathComponent(): helper function to return the nth component of a path
+ * params: dest - destination buffer
+ * params: path - full qualified path
+ * params: n - component number
+ * returns: pointer to destination on success, NULL on fail
+ */
+
+char *pathComponent(char *dest, const char *path, int n) {
+    int depth = pathDepth(path);
+    if(n > depth) return NULL;
+
+    int c = 0;
+    int len = 0;
+    for(int i = 0; i < strlen(path); i++) {
+        if(path[i] == '/') c++;
+        if(c > n) {
+            i++;
+            while(path[i] && (path[i] != '/')) {
+                dest[len] = path[i];
+                len++;
+                i++;
+            }
+
+            dest[len] = 0;
+            return dest;
+        }
+    }
+
+    return NULL;
+}

fs/lxfs/src/include/lxfs/lxfs.h

@@ -120,3 +120,12 @@ int lxfsWriteBlock(Mountpoint *, uint64_t, const void *);
 uint64_t lxfsNextBlock(Mountpoint *, uint64_t);
 uint64_t lxfsReadNextBlock(Mountpoint *, uint64_t, void *);
 uint64_t lxfsWriteNextBlock(Mountpoint *, uint64_t, const void *);
+
+Mountpoint *findMP(const char *);
+int pathDepth(const char *);
+char *pathComponent(char *, const char *, int);
+
+void lxfsOpen(OpenCommand *);
+void lxfsStat(StatCommand *);
+void lxfsRead(RWCommand *);
+void lxfsWrite(RWCommand *);