dfs refactor and clean up

dfs.c

 #include "dfs.h"
 
-void stack_enqueue(struct node *n, struct list_head *stack)
+void enqueue(struct directory *dr, struct list_head *stack)
 {
 	if (list_empty(stack))
 		INIT_LIST_HEAD(stack);
-	list_add(&n->list, stack);
+	list_add(&dr->list, stack);
 }
 
-struct node *stack_dequeue(struct list_head *stack)
+struct directory *dequeue(struct list_head *stack)
 {
-	struct node *n;
+	struct directory *dr;
 
 	if (list_empty(stack))
 		return NULL;
-	n = list_first_entry(stack, struct node, list);
-	list_del(&n->list);
+	dr = list_first_entry(stack, struct directory, list);
+	list_del(&dr->list);
 
-	return n;
+	return dr;
 }
 
-void add_visited(struct node *n, struct list_head *visited)
+bool search(char *path, struct list_head *visited)
 {
-	if (list_empty(visited))
-		INIT_LIST_HEAD(visited);
-	list_add(&n->list, visited);
-}
-
-bool is_visited(char *path, struct list_head *visited) // just visited
-{
-	struct node *tmp;
+	struct directory *dr;
 
-	list_for_each_entry(tmp, visited, list) {
-		if (strncmp(tmp->path, path, 1024) == 0)
+	list_for_each_entry(dr, visited, list) {
+		if (strncmp(dr->path, path, 1024) == 0)
 			return true;
 	}
 
 	return false;
 }
 
-void clear_list(struct list_head *visited)
+void clear_list(struct list_head *list)
 {
-	struct node *n, *tmp;
+	struct directory *dr, *tmp;
+	print_list_dfs(list);
+
+	if (list_empty(list))
+		return;
 
-	list_for_each_entry_safe(n, tmp, visited, list) {
-		free(n->path);
-		list_del(&n->list);
-		free(n);
+	list_for_each_entry_safe(dr, tmp, list, list) {
+		free(dr->path);
+		list_del(&dr->list);
+		free(dr);
 	}
 }
 
-void print_list_dfs(struct list_head *collection_of_nodes_and_stuff)
+void print_list_dfs(struct list_head *list)
 {
-	struct node *n;
+	struct directory *dr;
 
-	if (list_empty(collection_of_nodes_and_stuff))
+	if (list_empty(list))
 		return;
 
-	list_for_each_entry(n, collection_of_nodes_and_stuff, list) {
-		printf("path: %s\n", n->path);
+	list_for_each_entry(dr, list, list) {
+		printf("path: %s\n", dr->path);
 	}
 }
\ No newline at end of file

dfs.h

@@ -2,16 +2,14 @@
 #define DFS_H
 #include "common.h"
 
-struct node {
+struct directory {
 	struct list_head list;
-	char path[PATH_MAX]; //inefficient space complexity with defined memory allocation?
-	char *name;
+	char *path;
 };
 
-void stack_enqueue(struct node *n, struct list_head *stack);
-struct node *stack_dequeue(struct list_head *stack);
-void add_visited(struct node *n, struct list_head *visited);
-bool is_visited(char *path, struct list_head *visited);
+void enqueue(struct directory *n, struct list_head *stack);
+struct directory *dequeue(struct list_head *stack);
+bool search(char *path, struct list_head *visited);
 void clear_list(struct list_head *visited);
 void print_list_dfs(struct list_head *collection_of_nodes_and_stuff);
 #endif
\ No newline at end of file

dongle_infrastructure.c

@@ -219,34 +219,39 @@ fail:
 	return NULL;
 }
 
-char *dfs_get_path_name(char *folder_name)
+char *get_device_name(char *dir_name)
 {
-	char *path, *name, new_path[PATH_MAX];
-	struct stat st;
+	char *path, *name, tmp_path[PATH_MAX];
+	struct directory *dr, *sub_dr;
 	struct dirent *de;
-	DIR *dr;
-	struct node *n, *new_n;
+	struct stat st;
+	int path_len;
+	DIR *dir;
 
-	n = malloc(sizeof(struct node));
-	snprintf(n->path, PATH_MAX, "%s", folder_name); //remain allocated?
-	stack_enqueue(n, &stack);
+	dr = malloc(sizeof(struct directory));
+	if (!dr) {
+		perror("malloc");
+		goto fail;
+	}
+	dr->path = strdup(dir_name);
+	//snprintf(dr->path, PATH_MAX, "%s", dir_name); //remain allocated?
+	enqueue(dr, &stack);
 
 	while (!list_empty(&stack)) {
-		n = stack_dequeue(&stack);
-		path = n->path;
-		dr = opendir(path);
-		if (!dr) {
+		dr = dequeue(&stack);
+		dir = opendir(dr->path);
+		if (!dir) {
 			perror("opendir");
 			goto fail_opendir;
 		}
 
-		if (!is_visited(path, &visited)) {
-			add_visited(n, &visited);
-			while ((de = readdir(dr)) != NULL) {
+		if (!search(dr->path, &visited)) {
+			enqueue(dr, &visited);
+			while ((de = readdir(dir)) != NULL) {
 				if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0)
 					continue;
 
-				if (fstatat(dirfd(dr), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
+				if (fstatat(dirfd(dir), de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
 					perror("fstatat");
 					continue;
 				}
@@ -255,39 +260,61 @@ char *dfs_get_path_name(char *folder_name)
 					continue;
 
 				if (!strstr(de->d_name, "eth") && !strstr(de->d_name, "usb")) {
-					snprintf(new_path, PATH_MAX, "%s/%s", path, de->d_name);
-					if (!is_visited(new_path, &visited)) {
-						new_n = malloc(sizeof(struct node));
-						strncpy(new_n->path, new_path, (PATH_MAX-1));
-						//new_n->path= strdup(path);
-						stack_enqueue(new_n, &stack);
+					path_len = strlen(dr->path) + strlen(de->d_name)+2;
+					path = calloc(path_len, 1);
+					if (!path) {
+						perror("calloc");
+						goto fail_calloc;
 					}
+
+					snprintf(path, PATH_MAX, "%s%s/", dr->path, de->d_name);
+					if (!search(path, &visited)) {
+						sub_dr = malloc(sizeof(struct directory));
+						if (!sub_dr) {
+							perror("malloc");
+							goto fail_dir;
+						}
+						sub_dr->path = path;
+						enqueue(sub_dr, &stack);
+					} else
+						free(path);
 					continue;
 				}
 
-				if (strcmp(reverse_lexer(&path, '/'), "net") == 0) {
+				if (strstr(dr->path, "net")) {
 					printf("de->d_name %s\n", de->d_name);
 					name = strdup(de->d_name);
 					goto success;
 				}
 			}
 		}
-		closedir(dr);
+		closedir(dir);
 	}
+fail_dir:
+	//free(path);
+fail_calloc:
 	clear_list(&visited);
 fail_opendir:
+	//clear_list(&stack);
+fail:
 	return NULL;
 success:
-	closedir(dr);
+	printf("name %s\n", name);
+	clear_list(&visited);
+	printf("name %s\n", name);
+	clear_list(&stack);
+	printf("name %s\n", name);
+	closedir(dir);
 	return name;
 }
 
 char *get_interface_name(char *usb_path, char *sub_dir_name)
 {
-	char path[PATH_MAX], *name;
+	char path[PATH_MAX];
 
 	snprintf(path, PATH_MAX, "%s/%s/", usb_path, sub_dir_name);
-	return dfs_get_path_name(path);
+
+	return get_device_name(path);
 }
 
 int get_devices(void)
@@ -317,6 +344,7 @@ int get_devices(void)
 				continue;
 			}
 			name = get_interface_name(usb_path, de->d_name);
+			printf("returned name %s!\n", name);
 			if (!name)
 				continue;