From e2cd6ea5821976a2b651cb6a6ff658920580be6b Mon Sep 17 00:00:00 2001
From: "Linux-Fan, Ma_Sys.ma" <Ma_Sys.ma@web.de>
Date: Sun, 25 Aug 2024 15:33:30 +0200
Subject: [PATCH] Enable support for SIGWINCH reporting through ceKEY_RESIZE

Previously, window resizing was reported to the applications through the opaque
key code 410. Also, occasionally, the reported window size was wrong.

This commit attempts to fix this by adding a new constant `ceKEY_RESIZE` to
detect the virtual key reported by NCurses for resize events. Also, the code
is extended to explicitly query the current window size via `ioctl`.
---
 c_src/cecho.c     | 14 +++++++++++++-
 include/cecho.hrl |  2 +-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/c_src/cecho.c b/c_src/cecho.c
index 9dbc22e..81599a0 100644
--- a/c_src/cecho.c
+++ b/c_src/cecho.c
@@ -27,6 +27,7 @@
 // Includes
 #include <stdlib.h>
 #include <string.h>
+#include <sys/ioctl.h>
 #include "cecho.h"
 #include "cecho_commands.h"
 #include "erl_driver.h"
@@ -296,7 +297,18 @@ void do_getmaxyx(state *st) {
   long slot;
   int x, y;
   ei_decode_long(st->args, &(st->index), &slot);
-  getmaxyx(st->win[slot], y, x);
+  if (slot == 0) {
+    struct winsize w;
+    int rc = ioctl(0, TIOCGWINSZ, &w);
+    if (rc == 0) {
+      y = w.ws_row;
+      x = w.ws_col;
+    } else {
+      getmaxyx(st->win[slot], y, x);
+    }
+  } else {
+    getmaxyx(st->win[slot], y, x);
+  }
   tuple(&(st->eixb), 2);
   integer(&(st->eixb), y);
   integer(&(st->eixb), x);
diff --git a/include/cecho.hrl b/include/cecho.hrl
index d56d2c0..21a5148 100644
--- a/include/cecho.hrl
+++ b/include/cecho.hrl
@@ -99,4 +99,4 @@
 -define(ceKEY_PGUP, 339).
 -define(ceKEY_END, 360).
 
-
+-define(ceKEY_RESIZE, 410).