[EROFS] test: enhanced testing for same-name file or dir

Add tests for cases where file and directory have the same name.

Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>

Author: Hongzhen Luo

src/overlaybd/tar/erofs/test/erofs_stress_base.cpp

@@ -43,11 +43,57 @@ static bool is_substring(const std::string& str, const std::string& substring) {
     return str.find(substring) != std::string::npos;
 }
 
+static bool str_n_equal(std::string s1, std::string s2, long unsigned int n) {
+	if (s1.length() < n || s2.length() < n)
+			return false;
+	return s1.substr(0, n) == s2.substr(0, n);
+}
+
+bool StressFsTree::add_node(StressNode *node) {
+	if (!node || !node->path.size() || node->type >= NODE_TYPE_MAX)
+		LOG_ERRNO_RETURN(-1, false, "invalid node");
+
+	if (node->type != NODE_WHITEOUT) {
+		/* the upper regular file should remove the lower dir */
+		std::map<std::string, StressNode*>::iterator dir_it;
+		if (node->type == NODE_REGULAR && (dir_it = tree.find(node->path)) != tree.end() &&
+			dir_it->second->type == NODE_DIR)
+		{
+			tree.erase(dir_it);
+			std::string rm_prefix = node->path + "/";
+			for (auto it = tree.begin(); it != tree.end(); ) {
+				if (str_n_equal(rm_prefix, it->first, rm_prefix.length())) {
+					it = tree.erase(it);
+				} else {
+					++it;
+				}
+
+			}
+		}
+		tree[node->path] = node;
+	} else {
+		auto it = tree.find(node->path);
+		if (it == tree.end() || it->second->type == NODE_WHITEOUT)
+			LOG_ERROR_RETURN(-1, false, "whiteout a invalid object");
+		if (it->second->type == NODE_REGULAR)
+			tree.erase(it);
+		else {
+			std::string prefix = it->first;
+			for (auto p = tree.begin(); p != tree.end();) {
+				if (prefix.compare(0, prefix.size(), p->first) == 0)
+					p = tree.erase(p);
+				else
+					p ++;
+			}
+		}
+	}
+	return true;
+}
+
 std::string StressFsTree::get_same_name(int idx, int depth, std::string root_path, NODE_TYPE type) {
 	std::vector<std::string> vec;
 	for (const auto& pair : tree) {
-		if (pair.first == "/" || pair.second->type != type ||
-		    !is_substring(pair.first, root_path) ||
+		if (pair.first == "/" || !is_substring(pair.first, root_path) ||
 		    pair.first.length() == root_path.length())
 			continue;
 		std::string last_component = pair.first.substr(root_path.length() + 1);

src/overlaybd/tar/erofs/test/erofs_stress_base.h

@@ -166,36 +166,17 @@ class StressFsTree {
 	}
 
 	// build process
-	bool add_node(StressNode *node) {
-		if (!node || !node->path.size() || node->type >= NODE_TYPE_MAX)
-			LOG_ERRNO_RETURN(-1, false, "invalid node");
-
-		if (node->type != NODE_WHITEOUT) {
-			tree[node->path] = node;
-		} else {
-			auto it = tree.find(node->path);
-			if (it == tree.end() || it->second->type == NODE_WHITEOUT)
-				LOG_ERROR_RETURN(-1, false, "whiteout a invalid object");
-			if (it->second->type == NODE_REGULAR)
-				tree.erase(it);
-			else {
-				std::string prefix = it->first;
-				for (auto p = tree.begin(); p != tree.end();) {
-					if (prefix.compare(0, prefix.size(), p->first) == 0)
-						p = tree.erase(p);
-					else
-						p ++;
-				}
-			}
-		}
-		return true;
-	}
+	bool add_node(StressNode *node);
 
 	// verify process
 	bool query_delete_node(StressNode *node) {
 		auto it = tree.find(node->path);
-		if (it == tree.end() || !it->second || !it->second->equal(node))
-			return false;
+		if (it == tree.end())
+				LOG_ERROR_RETURN(-1,false, "path ` does not exist in in-mem tree", node->path);
+		if (!it->second)
+				LOG_ERROR_RETURN(-1, false, "NULL in-mem info (`)", node->path);
+		if (!it->second->equal(node))
+				LOG_ERROR_RETURN(-1, false, "node contents mismatch");
 		tree.erase(it);
 		return true;
 	}