Introduce nvim namespace: Move files.

Move files from src/ to src/nvim/.
- src/nvim/ becomes the new root dir for nvim executable sources.
- src/libnvim/ is planned to become root dir of the neovim library.

src/nvim/api/window.c

@@ -0,0 +1,184 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#include "api/window.h"
+#include "api/defs.h"
+#include "api/helpers.h"
+#include "../vim.h"
+#include "../window.h"
+#include "screen.h"
+#include "misc2.h"
+
+
+Buffer window_get_buffer(Window window, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return 0;
+  }
+
+  return win->w_buffer->b_fnum;
+}
+
+Position window_get_cursor(Window window, Error *err)
+{
+  Position rv = {.row = 0, .col = 0};
+  win_T *win = find_window(window, err);
+
+  if (win) {
+    rv.row = win->w_cursor.lnum;
+    rv.col = win->w_cursor.col;
+  }
+
+  return rv;
+}
+
+void window_set_cursor(Window window, Position pos, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return;
+  }
+
+  if (pos.row <= 0 || pos.row > win->w_buffer->b_ml.ml_line_count) {
+    set_api_error("cursor position outside buffer", err);
+    return;
+  }
+
+  win->w_cursor.lnum = pos.row;
+  win->w_cursor.col = pos.col;
+  win->w_cursor.coladd = 0;
+  // When column is out of range silently correct it.
+  check_cursor_col_win(win);
+  update_screen(VALID);
+}
+
+int64_t window_get_height(Window window, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return 0;
+  }
+
+  return win->w_height;
+}
+
+void window_set_height(Window window, int64_t height, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return;
+  }
+
+  win_T *savewin = curwin;
+  curwin = win;
+  try_start();
+  win_setheight(height);
+  curwin = savewin;
+  try_end(err);
+}
+
+int64_t window_get_width(Window window, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return 0;
+  }
+
+  return win->w_width;
+}
+
+void window_set_width(Window window, int64_t width, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return;
+  }
+
+  win_T *savewin = curwin;
+  curwin = win;
+  try_start();
+  win_setwidth(width);
+  curwin = savewin;
+  try_end(err);
+}
+
+Object window_get_var(Window window, String name, Error *err)
+{
+  Object rv;
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return rv;
+  }
+
+  return dict_get_value(win->w_vars, name, err);
+}
+
+Object window_set_var(Window window, String name, Object value, Error *err)
+{
+  Object rv;
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return rv;
+  }
+
+  return dict_set_value(win->w_vars, name, value, err);
+}
+
+Object window_get_option(Window window, String name, Error *err)
+{
+  Object rv;
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return rv;
+  }
+
+  return get_option_from(win, SREQ_WIN, name, err);
+}
+
+void window_set_option(Window window, String name, Object value, Error *err)
+{
+  win_T *win = find_window(window, err);
+
+  if (!win) {
+    return;
+  }
+
+  set_option_to(win, SREQ_WIN, name, value, err);
+}
+
+Position window_get_position(Window window, Error *err)
+{
+  Position rv;
+  win_T *win = find_window(window, err);
+
+  if (win) {
+    rv.col = win->w_wincol;
+    rv.row = win->w_winrow;
+  }
+
+  return rv;
+}
+
+Tabpage window_get_tabpage(Window window, Error *err)
+{
+  set_api_error("Not implemented", err);
+  return 0;
+}
+
+bool window_is_valid(Window window)
+{
+  Error stub = {.set = false};
+  return find_window(window, &stub) != NULL;
+}
+