Merge "[incfs] Optimize path::join for appending" into sc-dev (d0980160) · Commits · e / os / android_frameworks_base

services/incremental/path.cpp

+8 −7

Original line number	Diff line number	Diff line
		@@ -44,19 +44,20 @@ bool PathLess::operator()(std::string_view l, std::string_view r) const {
		PathCharsLess());
		}

		static void preparePathComponent(std::string_view& path, bool trimFront) {
		if (trimFront) {
		while (!path.empty() && path.front() == '/') {
		static void preparePathComponent(std::string_view& path, bool trimAll) {
		// need to check for double front slash as a single one has a separate meaning in front
		while (!path.empty() && path.front() == '/' &&
		(trimAll \|\| (path.size() > 1 && path[1] == '/'))) {
		path.remove_prefix(1);
		}
		}
		while (!path.empty() && path.back() == '/') {
		// for the back we don't care about double-vs-single slash difference
		while (path.size() > !trimAll && path.back() == '/') {
		path.remove_suffix(1);
		}
		}

		void details::append_next_path(std::string& target, std::string_view path) {
		preparePathComponent(path, true);
		preparePathComponent(path, !target.empty());
		if (path.empty()) {
		return;
		}

+15 −5

Original line number	Diff line number	Diff line
		@@ -89,15 +89,25 @@ std::optional<bool> isEmptyDir(std::string_view dir);
		bool startsWith(std::string_view path, std::string_view prefix);

		template <class... Paths>
		std::string join(std::string_view first, std::string_view second, Paths&&... paths) {
		std::string result;
		std::string join(std::string&& first, std::string_view second, Paths&&... paths) {
		std::string& result = first;
		{
		using std::size;
		result.reserve(first.size() + second.size() + 1 + (sizeof...(paths) + ... + size(paths)));
		}
		result.assign(first);
		(details::append_next_path(result, second), ..., details::append_next_path(result, paths));
		return result;
		(details::append_next_path(result, second), ...,
		details::append_next_path(result, std::forward<Paths>(paths)));
		return std::move(result);
		}

		template <class... Paths>
		std::string join(std::string_view first, std::string_view second, Paths&&... paths) {
		return path::join(std::string(), first, second, std::forward<Paths>(paths)...);
		}

		template <class... Paths>
		std::string join(const char* first, std::string_view second, Paths&&... paths) {
		return path::join(std::string_view(first), second, std::forward<Paths>(paths)...);
		}

		} // namespace android::incremental::path

+20 −0

Original line number	Diff line number	Diff line
		@@ -40,4 +40,24 @@ TEST(Path, Comparator) {
		EXPECT_TRUE(!PathLess()("/a/b", "/a"));
		}

		TEST(Path, Join) {
		EXPECT_STREQ("", path::join("", "").c_str());

		EXPECT_STREQ("/", path::join("", "/").c_str());
		EXPECT_STREQ("/", path::join("/", "").c_str());
		EXPECT_STREQ("/", path::join("/", "/").c_str());
		EXPECT_STREQ("/", path::join("/"s, "/").c_str());
		EXPECT_STREQ("/", path::join("/"sv, "/").c_str());
		EXPECT_STREQ("/", path::join("/", "/", "/", "/", "/", "/", "/", "/", "/", "/").c_str());

		EXPECT_STREQ("/a/b/c/d", path::join("/a/b/"s, "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("/a/b/", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("/", "a/b/", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("/", "a/b", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("/", "//a/b//", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("", "", "/", "//a/b//", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join(""s, "", "/", "//a/b//", "c", "d").c_str());
		EXPECT_STREQ("/a/b/c/d", path::join("/a/b", "", "", "/", "", "/", "/", "/c", "d").c_str());
		}

		} // namespace android::incremental::path