Fix RemoveRelatvePathComponents

This used to return "/foo" for "../foo" when it should return the enpty
string (i.e., error removing all relative components).

diff --git a/src/filesys.cpp b/src/filesys.cpp
index c718a9689fc8bcde8dd522dd91564ad7cdbe9061..bd8b94aff98ff86ebf2ca6a0a5383c4625fd8717 100644 (file)
--- a/src/filesys.cpp
+++ b/src/filesys.cpp
@@ -617,48 +617,51 @@ std::string RemoveRelativePathComponents(std::string path)
 {
        size_t pos = path.size();
        size_t dotdot_count = 0;
-       while(pos != 0){
+       while (pos != 0) {
                size_t component_with_delim_end = pos;
                // skip a dir delimiter
-               while(pos != 0 && IsDirDelimiter(path[pos-1]))
+               while (pos != 0 && IsDirDelimiter(path[pos-1]))
                        pos--;
                // strip a path component
                size_t component_end = pos;
-               while(pos != 0 && !IsDirDelimiter(path[pos-1]))
+               while (pos != 0 && !IsDirDelimiter(path[pos-1]))
                        pos--;
                size_t component_start = pos;
 
                std::string component = path.substr(component_start,
                                component_end - component_start);
                bool remove_this_component = false;
-               if(component == "." && component_start != 0){
+               if (component == ".") {
                        remove_this_component = true;
-               }
-               else if(component == ".."){
+               } else if (component == "..") {
                        remove_this_component = true;
                        dotdot_count += 1;
-               }
-               else if(dotdot_count != 0){
+               } else if (dotdot_count != 0) {
                        remove_this_component = true;
                        dotdot_count -= 1;
                }
 
-               if(remove_this_component){
-                       while(pos != 0 && IsDirDelimiter(path[pos-1]))
+               if (remove_this_component) {
+                       while (pos != 0 && IsDirDelimiter(path[pos-1]))
                                pos--;
-                       path = path.substr(0, pos) + DIR_DELIM +
-                               path.substr(component_with_delim_end,
-                                               std::string::npos);
-                       pos++;
+                       if (component_start == 0) {
+                               // We need to remove the delemiter too
+                               path = path.substr(component_with_delim_end, std::string::npos);
+                       } else {
+                               path = path.substr(0, pos) + DIR_DELIM +
+                                       path.substr(component_with_delim_end, std::string::npos);
+                       }
+                       if (pos > 0)
+                               pos++;
                }
        }
 
-       if(dotdot_count > 0)
+       if (dotdot_count > 0)
                return "";
 
        // remove trailing dir delimiters
        pos = path.size();
-       while(pos != 0 && IsDirDelimiter(path[pos-1]))
+       while (pos != 0 && IsDirDelimiter(path[pos-1]))
                pos--;
        return path.substr(0, pos);
 }

diff --git a/src/unittest/test_filepath.cpp b/src/unittest/test_filepath.cpp
index 5e3cdcc089fbf86659bb4ecdaba06ac81bb1b3d9..ac2d69b5a443b4a5e85ce132dbe1cf64f7fcd152 100644 (file)
--- a/src/unittest/test_filepath.cpp
+++ b/src/unittest/test_filepath.cpp
@@ -251,7 +251,10 @@ void TestFilePath::testRemoveRelativePathComponent()
        UASSERT(result == p("/home/user/minetest/worlds/world1"));
        path = p(".");
        result = fs::RemoveRelativePathComponents(path);
-       UASSERT(result == ".");
+       UASSERT(result == "");
+       path = p("../a");
+       result = fs::RemoveRelativePathComponents(path);
+       UASSERT(result == "");
        path = p("./subdir/../..");
        result = fs::RemoveRelativePathComponents(path);
        UASSERT(result == "");