1 files changed, 34 insertions, 0 deletions
diff --git a/prism/internal/line_offset_list.h b/prism/internal/line_offset_list.h
new file mode 100644
index 0000000000..dac9f7052e
--- /dev/null
+++ b/prism/internal/line_offset_list.h
@@ -0,0 +1,34 @@
+#ifndef PRISM_INTERNAL_LINE_OFFSET_LIST_H
+#define PRISM_INTERNAL_LINE_OFFSET_LIST_H
+
+#include "prism/compiler/force_inline.h"
+
+#include "prism/arena.h"
+#include "prism/line_offset_list.h"
+
+/* Initialize a new line offset list with the given capacity. */
+void pm_line_offset_list_init(pm_arena_t *arena, pm_line_offset_list_t *list, size_t capacity);
+
+/* Clear out the offsets that have been appended to the list. */
+void pm_line_offset_list_clear(pm_line_offset_list_t *list);
+
+/* Append a new offset to the list (slow path with resize). */
+void pm_line_offset_list_append_slow(pm_arena_t *arena, pm_line_offset_list_t *list, uint32_t cursor);
+
+/* Append a new offset to the list. */
+static PRISM_FORCE_INLINE void
+pm_line_offset_list_append(pm_arena_t *arena, pm_line_offset_list_t *list, uint32_t cursor) {
+    if (list->size < list->capacity) {
+        list->offsets[list->size++] = cursor;
+    } else {
+        pm_line_offset_list_append_slow(arena, list, cursor);
+    }
+}
+
+/*
+ * Returns the line of the given offset. If the offset is not in the list, the
+ * line of the closest offset less than the given offset is returned.
+ */
+int32_t pm_line_offset_list_line(const pm_line_offset_list_t *list, uint32_t cursor, int32_t start_line);
+
+#endif