api/buffer: add "on_bytes" callback to nvim_buf_attach

This implements byte-resolution updates of buffer changes.
Note: there is no promise that the buffer state is valid inside
the callback!

1 files changed, 9 insertions, 3 deletions

diff --git a/src/nvim/extmark.h b/src/nvim/extmark.h
index e1197834bd..534e97a7f4 100644
--- a/src/nvim/extmark.h
+++ b/src/nvim/extmark.h
@@ -20,6 +20,9 @@ typedef struct
 
 typedef kvec_t(ExtmarkInfo) ExtmarkInfoArray;
 
+// TODO(bfredl): good enough name for now.
+typedef ptrdiff_t bcount_t;
+
 
 // delete the columns between mincol and endcol
 typedef struct {
@@ -29,9 +32,9 @@ typedef struct {
   colnr_T old_col;
   int new_row;
   colnr_T new_col;
-  size_t start_byte;
-  size_t old_byte;
-  size_t new_byte;
+  bcount_t start_byte;
+  bcount_t old_byte;
+  bcount_t new_byte;
 } ExtmarkSplice;
 
 // adjust marks after :move operation
@@ -42,6 +45,9 @@ typedef struct {
   int extent_col;
   int new_row;
   int new_col;
+  bcount_t start_byte;
+  bcount_t extent_byte;
+  bcount_t new_byte;
 } ExtmarkMove;
 
 // extmark was updated