nsmarks: initial commit

src/nvim/buffer_defs.h

@@ -115,6 +115,9 @@ typedef uint16_t disptick_T;  // display tick type
 #include "nvim/os/fs_defs.h"    // for FileID
 #include "nvim/terminal.h"      // for Terminal
 
+#include "nvim/lib/kbtree.h"
+#include "nvim/mark_extended.h"
+
 /*
  * The taggy struct is used to store the information about a :tag command.
  */
@@ -805,6 +808,10 @@ struct file_buffer {
 
   kvec_t(BufhlLine *) b_bufhl_move_space;  // temporary space for highlights
 
+  PMap(uint64_t) *b_extmark_ns;         // extmark namespaces
+  kbtree_t(extlines) b_extlines;  // extmarks
+  kvec_t(ExtMarkLine *) b_extmark_move_space;  // temp space for extmarks
+
   // array of channel_id:s which have asked to receive updates for this
   // buffer.
   kvec_t(uint64_t) update_channels;