3 files changed, 40 insertions, 0 deletions

diff --git a/src/filesystem.c b/src/filesystem.c
index 0ec9802..0482336 100644
--- a/src/filesystem.c
+++ b/src/filesystem.c
@@ -135,6 +135,16 @@ lilv_path_absolute(const char* path)
 }
 
 char*
+lilv_path_absolute_child(const char* path, const char* parent)
+{
+	if (lilv_path_is_absolute(path)) {
+		return lilv_strdup(path);
+	}
+
+	return lilv_path_join(parent, path);
+}
+
+char*
 lilv_path_relative_to(const char* path, const char* base)
 {
 	const size_t path_len = strlen(path);
diff --git a/src/filesystem.h b/src/filesystem.h
index 319dd49..f888f5f 100644
--- a/src/filesystem.h
+++ b/src/filesystem.h
@@ -43,6 +43,15 @@ char*
 lilv_path_absolute(const char* path);
 
 /**
+   Return `path` as an absolute path relative to `parent`.
+
+   If `path` is absolute, an identical copy of it is returned.  Otherwise, the
+   returned path is relative to `parent`.
+*/
+char*
+lilv_path_absolute_child(const char* path, const char* parent);
+
+/**
    Return `path` relative to `base` if possible.
 
    If `path` is not within `base`, a copy is returned.  Otherwise, an
diff --git a/test/test_filesystem.c b/test/test_filesystem.c
index a3288ed..01ca5ae 100644
--- a/test/test_filesystem.c
+++ b/test/test_filesystem.c
@@ -105,6 +105,26 @@ test_path_absolute(void)
 }
 
 static void
+test_path_absolute_child(void)
+{
+	const char* const parent     = "/parent";
+	const char* const short_path = "a";
+	const char* const long_path  = "a/b/c";
+
+	char* const expected_short = lilv_path_join(parent, short_path);
+	char* const expected_long  = lilv_path_join(parent, long_path);
+
+	assert(equals(lilv_path_absolute_child(short_path, parent),
+	              expected_short));
+
+	assert(equals(lilv_path_absolute_child(long_path, parent),
+	              expected_long));
+
+	free(expected_long);
+	free(expected_short);
+}
+
+static void
 test_path_relative_to(void)
 {
 	assert(equals(lilv_path_relative_to("/a/b", "/a/"), "b"));
@@ -478,6 +498,7 @@ main(void)
 	test_path_is_child();
 	test_path_current();
 	test_path_absolute();
+	test_path_absolute_child();
 	test_path_relative_to();
 	test_path_parent();
 	test_path_filename();