Added sb_pushline4 screen callback, which adds an extra 'continuation…

…' argument

include/vterm.h

@@ -545,13 +545,17 @@ typedef struct {
   int (*sb_pushline)(int cols, const VTermScreenCell *cells, void *user);
   int (*sb_popline)(int cols, VTermScreenCell *cells, void *user);
   int (*sb_clear)(void* user);
+  /* ABI-compat this is only used if vterm_screen_callbacks_has_pushline4() is called */
+  int (*sb_pushline4)(int cols, const VTermScreenCell *cells, bool continuation, void *user);
 } VTermScreenCallbacks;
 
 VTermScreen *vterm_obtain_screen(VTerm *vt);
 
 void  vterm_screen_set_callbacks(VTermScreen *screen, const VTermScreenCallbacks *callbacks, void *user);
 void *vterm_screen_get_cbdata(VTermScreen *screen);
 
+void vterm_screen_callbacks_has_pushline4(VTermScreen *screen);
+
 void  vterm_screen_set_unrecognised_fallbacks(VTermScreen *screen, const VTermStateFallbacks *fallbacks, void *user);
 void *vterm_screen_get_unrecognised_fbdata(VTermScreen *screen);
 

src/screen.c

@@ -48,6 +48,7 @@ struct VTermScreen
 
   const VTermScreenCallbacks *callbacks;
   void *cbdata;
+  bool callbacks_has_pushline4;
 
   VTermDamageSize damage_merge;
   /* start_row == -1 => no damage */
@@ -205,25 +206,31 @@ static int putglyph(VTermGlyphInfo *info, VTermPos pos, void *user)
   return 1;
 }
 
-static void sb_pushline_from_row(VTermScreen *screen, int row)
+static void sb_pushline_from_row(VTermScreen *screen, int row, bool continuation)
 {
   VTermPos pos = { .row = row };
   for(pos.col = 0; pos.col < screen->cols; pos.col++)
     vterm_screen_get_cell(screen, pos, screen->sb_buffer + pos.col);
 
-  (screen->callbacks->sb_pushline)(screen->cols, screen->sb_buffer, screen->cbdata);
+  if(screen->callbacks_has_pushline4 && screen->callbacks->sb_pushline4)
+    (screen->callbacks->sb_pushline4)(screen->cols, screen->sb_buffer, continuation, screen->cbdata);
+  else
+    (screen->callbacks->sb_pushline)(screen->cols, screen->sb_buffer, screen->cbdata);
 }
 
 static int premove(VTermRect rect, void *user)
 {
   VTermScreen *screen = user;
 
-  if(screen->callbacks && screen->callbacks->sb_pushline &&
+  if(((screen->callbacks && screen->callbacks->sb_pushline) ||
+        (screen->callbacks_has_pushline4 && screen->callbacks && screen->callbacks->sb_pushline4)) &&
      rect.start_row == 0 && rect.start_col == 0 &&        // starts top-left corner
      rect.end_col == screen->cols &&                      // full width
      screen->buffer == screen->buffers[BUFIDX_PRIMARY]) { // not altscreen
-    for(int row = 0; row < rect.end_row; row++)
-      sb_pushline_from_row(screen, row);
+    for(int row = 0; row < rect.end_row; row++) {
+      const VTermLineInfo *lineinfo = vterm_state_get_lineinfo(screen->state, row);
+      sb_pushline_from_row(screen, row, lineinfo->continuation);
+    }
   }
 
   return 1;
@@ -674,9 +681,12 @@ static void resize_buffer(VTermScreen *screen, int bufidx, int new_rows, int new
 
   if(old_row >= 0 && bufidx == BUFIDX_PRIMARY) {
     /* Push spare lines to scrollback buffer */
-    if(screen->callbacks && screen->callbacks->sb_pushline)
-      for(int row = 0; row <= old_row; row++)
-        sb_pushline_from_row(screen, row);
+    if((screen->callbacks && screen->callbacks->sb_pushline) ||
+          (screen->callbacks_has_pushline4 && screen->callbacks && screen->callbacks->sb_pushline4))
+      for(int row = 0; row <= old_row; row++) {
+        const VTermLineInfo *lineinfo = old_lineinfo + row;
+        sb_pushline_from_row(screen, row, lineinfo->continuation);
+      }
     if(active)
       statefields->pos.row -= (old_row + 1);
   }
@@ -884,6 +894,7 @@ static VTermScreen *screen_new(VTerm *vt)
 
   screen->callbacks = NULL;
   screen->cbdata    = NULL;
+  screen->callbacks_has_pushline4 = false;
 
   screen->buffers[BUFIDX_PRIMARY] = alloc_buffer(screen, rows, cols);
 
@@ -1070,6 +1081,11 @@ void *vterm_screen_get_cbdata(VTermScreen *screen)
   return screen->cbdata;
 }
 
+void vterm_screen_callbacks_has_pushline4(VTermScreen *screen)
+{
+  screen->callbacks_has_pushline4 = true;
+}
+
 void vterm_screen_set_unrecognised_fallbacks(VTermScreen *screen, const VTermStateFallbacks *fallbacks, void *user)
 {
   vterm_state_set_unrecognised_fallbacks(screen->state, fallbacks, user);

t/harness.c

@@ -582,7 +582,7 @@ static int screen_damage(VTermRect rect, void *user)
 }
 
 static int want_screen_scrollback = 0;
-static int screen_sb_pushline(int cols, const VTermScreenCell *cells, void *user)
+static int screen_sb_pushline4(int cols, const VTermScreenCell *cells, bool continuation, void *user)
 {
   if(!want_screen_scrollback)
     return 1;
@@ -591,7 +591,7 @@ static int screen_sb_pushline(int cols, const VTermScreenCell *cells, void *user
   while(eol && !cells[eol-1].chars[0])
     eol--;
 
-  printf("sb_pushline %d =", cols);
+  printf("sb_pushline %d%s =", cols, continuation ? " cont" : "");
   for(int c = 0; c < eol; c++)
     printf(" %02X", cells[c].chars[0]);
   printf("\n");
@@ -628,13 +628,13 @@ static int screen_sb_clear(void *user)
 }
 
 VTermScreenCallbacks screen_cbs = {
-  .damage      = screen_damage,
-  .moverect    = moverect,
-  .movecursor  = movecursor,
-  .settermprop = settermprop,
-  .sb_pushline = screen_sb_pushline,
-  .sb_popline  = screen_sb_popline,
-  .sb_clear    = screen_sb_clear,
+  .damage       = screen_damage,
+  .moverect     = moverect,
+  .movecursor   = movecursor,
+  .settermprop  = settermprop,
+  .sb_popline   = screen_sb_popline,
+  .sb_clear     = screen_sb_clear,
+  .sb_pushline4 = screen_sb_pushline4,
 };
 
 int main(int argc, char **argv)
@@ -725,6 +725,7 @@ int main(int argc, char **argv)
       if(!screen)
         screen = vterm_obtain_screen(vt);
       vterm_screen_set_callbacks(screen, &screen_cbs, NULL);
+      vterm_screen_callbacks_has_pushline4(screen);
 
       int i = 10;
       int sense = 1;