tui: rework deferred-termcodes implementation

src/nvim/os/pty_process_unix.c

@@ -72,8 +72,7 @@ int pty_process_spawn(PtyProcess *ptyproc)
     ELOG("forkpty failed: %s", strerror(errno));
     return status;
   } else if (pid == 0) {
-    init_child(ptyproc);
-    abort();
+    init_child(ptyproc);  // never returns
   }
 
   // make sure the master file descriptor is non blocking
@@ -163,14 +162,15 @@ static void init_child(PtyProcess *ptyproc) FUNC_ATTR_NONNULL_ALL
 
   Process *proc = (Process *)ptyproc;
   if (proc->cwd && os_chdir(proc->cwd) != 0) {
-    fprintf(stderr, "chdir failed: %s\n", strerror(errno));
+    ELOG("chdir failed: %s", strerror(errno));
     return;
   }
 
   char *prog = ptyproc->process.argv[0];
   setenv("TERM", ptyproc->term_name ? ptyproc->term_name : "ansi", 1);
   execvp(prog, ptyproc->process.argv);
-  fprintf(stderr, "execvp failed: %s: %s\n", strerror(errno), prog);
+  ELOG("execvp failed: %s: %s", strerror(errno), prog);
+  _exit(122);  // 122 is EXEC_FAILED in the Vim source.
 }
 
 static void init_termios(struct termios *termios) FUNC_ATTR_NONNULL_ALL

src/nvim/os/signal.c

@@ -10,6 +10,7 @@
 #endif
 
 #include "nvim/ascii.h"
+#include "nvim/log.h"
 #include "nvim/vim.h"
 #include "nvim/globals.h"
 #include "nvim/memline.h"
@@ -162,7 +163,7 @@ static void on_signal(SignalWatcher *handle, int signum, void *data)
       }
       break;
     default:
-      fprintf(stderr, "Invalid signal %d", signum);
+      ELOG("invalid signal: %d", signum);
       break;
   }
 }

src/nvim/tui/tui.c

@@ -70,6 +70,7 @@ typedef struct {
   UIBridgeData *bridge;
   Loop *loop;
   bool stop;
+  uv_timer_t after_startup_timer;
   unibi_var_t params[9];
   char buf[OUTBUF_SIZE];
   size_t bufpos;
@@ -169,24 +170,6 @@ static size_t unibi_pre_fmt_str(TUIData *data, unsigned int unibi_index,
   return unibi_run(str, data->params, buf, len);
 }
 
-/// Emits some termcodes after Nvim startup, which were observed to slowdown
-/// rendering during startup in tmux 2.3 (+focus-events). #7649
-static void terminfo_after_startup_event(void **argv)
-{
-  UI *ui = argv[0];
-  bool defer = argv[1] != NULL;  // clever(?) boolean without malloc() dance.
-  TUIData *data = ui->data;
-  if (defer) {  // We're on the main-loop. Now forward to the TUI loop.
-    loop_schedule(data->loop,
-                  event_create(terminfo_after_startup_event, 2, ui, NULL));
-    return;
-  }
-  // Enable bracketed paste
-  unibi_out_ext(ui, data->unibi_ext.enable_bracketed_paste);
-  // Enable focus reporting
-  unibi_out_ext(ui, data->unibi_ext.enable_focus_reporting);
-}
-
 static void termname_set_event(void **argv)
 {
   char *termname = argv[0];
@@ -266,6 +249,9 @@ static void terminfo_start(UI *ui)
   unibi_out(ui, unibi_enter_ca_mode);
   unibi_out(ui, unibi_keypad_xmit);
   unibi_out(ui, unibi_clear_screen);
+  // Enable bracketed paste
+  unibi_out_ext(ui, data->unibi_ext.enable_bracketed_paste);
+
   uv_loop_init(&data->write_loop);
   if (data->out_isatty) {
     uv_tty_init(&data->write_loop, &data->output_handle.tty, data->out_fd, 0);
@@ -278,9 +264,6 @@ static void terminfo_start(UI *ui)
     uv_pipe_init(&data->write_loop, &data->output_handle.pipe, 0);
     uv_pipe_open(&data->output_handle.pipe, data->out_fd);
   }
-
-  loop_schedule(&main_loop,
-                event_create(terminfo_after_startup_event, 2, ui, ui));
 }
 
 static void terminfo_stop(UI *ui)
@@ -308,6 +291,18 @@ static void terminfo_stop(UI *ui)
   unibi_destroy(data->ut);
 }
 
+static void after_startup_timer_cb(uv_timer_t *handle)
+  FUNC_ATTR_NONNULL_ALL
+{
+  UI *ui = handle->data;
+  TUIData *data = ui->data;
+  uv_timer_stop(&data->after_startup_timer);
+
+  // Emit this after Nvim startup, not during.  This works around a tmux
+  // 2.3 bug(?) which caused slow drawing during startup.  #7649
+  unibi_out_ext(ui, data->unibi_ext.enable_focus_reporting);
+}
+
 static void tui_terminal_start(UI *ui)
 {
   TUIData *data = ui->data;
@@ -317,6 +312,8 @@ static void tui_terminal_start(UI *ui)
   update_size(ui);
   signal_watcher_start(&data->winch_handle, sigwinch_cb, SIGWINCH);
   term_input_start(&data->input);
+
+  uv_timer_start(&data->after_startup_timer, after_startup_timer_cb, 500, 0);
 }
 
 static void tui_terminal_stop(UI *ui)
@@ -350,6 +347,8 @@ static void tui_main(UIBridgeData *bridge, UI *ui)
 #ifdef UNIX
   signal_watcher_start(&data->cont_handle, sigcont_cb, SIGCONT);
 #endif
+  uv_timer_init(&data->loop->uv, &data->after_startup_timer);
+  data->after_startup_timer.data = ui;
 
 #if TERMKEY_VERSION_MAJOR > 0 || TERMKEY_VERSION_MINOR > 18
   data->input.tk_ti_hook_fn = tui_tk_ti_getstr;
@@ -368,6 +367,7 @@ static void tui_main(UIBridgeData *bridge, UI *ui)
     loop_poll_events(&tui_loop, -1);  // tui_loop.events is never processed
   }
 
+  uv_close((uv_handle_t *)&data->after_startup_timer, NULL);
   ui_bridge_stopped(bridge);
   term_input_destroy(&data->input);
   signal_watcher_stop(&data->cont_handle);

src/nvim/ui.h

@@ -31,11 +31,9 @@ struct ui_t {
   bool ui_ext[UI_WIDGETS];  ///< Externalized widgets
   int width, height;
   void *data;
-
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "ui_events.generated.h"
 #endif
-
   void (*event)(UI *ui, char *name, Array args, bool *args_consumed);
   void (*stop)(UI *ui);
 };