Add path.

2 files changed, 38 insertions, 6 deletions

diff --git a/filesystem/include/filesystem.h b/filesystem/include/filesystem.h
index 3dce87f..1c354b7 100644
--- a/filesystem/include/filesystem.h
+++ b/filesystem/include/filesystem.h
@@ -3,7 +3,6 @@
  */
 #pragma once
 
-#include <stdbool.h>
 #include <stddef.h>
 #include <stdio.h>
 
@@ -12,8 +11,3 @@ size_t get_file_size(FILE* file);
 
 /// Read the entire contents of the file into memory.
 void* read_file(const char* filepath);
-
-/// Make a path relative to the parent directory of a file.
-bool make_relative_path(
-    const char* filepath, const char* path, char* relative,
-    size_t relative_length);
diff --git a/filesystem/include/path.h b/filesystem/include/path.h
new file mode 100644
index 0000000..8ad885d
--- /dev/null
+++ b/filesystem/include/path.h
@@ -0,0 +1,38 @@
+#pragma once
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+
+typedef struct path {
+  char*  data;
+  size_t size; // Does not include null terminator. 0 if data is null.
+} path;
+
+/// Create a new path.
+path path_new(const char*);
+
+/// Free the path's memory.
+void path_del(path*);
+
+/// Return a C string from the path.
+static inline const char* path_cstr(path p) { return p.data; }
+
+/// Return true if the path is empty, false otherwise.
+static inline bool path_empty(path p) {
+  assert((p.data != 0) || (p.size == 0)); // null data -> 0 size
+  return p.data != 0;
+}
+
+/// Returns the parent directory, or empty path if the given path has no parent.
+/// The returned path is a slice of the input path; this function does not
+/// allocate.
+path path_parent_dir(path);
+
+/// Concatenate two paths.
+path path_concat(path left, path right);
+
+/// Make a path relative to the parent directory of a file.
+bool path_make_relative(
+    const char* filepath, const char* path, char* relative,
+    size_t relative_length);