From f5d6386ea580569cce8ea2bbfadd25de70291bfd Mon Sep 17 00:00:00 2001
From: Adam Saponara <as@php.net>
Date: Mon, 6 Nov 2023 22:21:02 -0500
Subject: [PATCH] fix egc bug, clarify docs, add test

---
 termbox2.h                   | 10 +++++-----
 tests/test_egc/expected.ansi | 24 ++++++++++++++++++++++++
 tests/test_egc/test.php      | 29 +++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 5 deletions(-)
 create mode 100644 tests/test_egc/expected.ansi
 create mode 100755 tests/test_egc/test.php

diff --git a/termbox2.h b/termbox2.h
index 8f8cb4b..a716dbd 100644
--- a/termbox2.h
+++ b/termbox2.h
@@ -411,13 +411,13 @@ typedef uint16_t uintattr_t;
  * See tb_present() for implementation.
  */
 struct tb_cell {
-    uint32_t ch;   /* a Unicode character */
+    uint32_t ch;   /* a Unicode code point */
     uintattr_t fg; /* bitwise foreground attributes */
     uintattr_t bg; /* bitwise background attributes */
 #ifdef TB_OPT_EGC
-    uint32_t *ech; /* a grapheme cluster of Unicode code points */
-    size_t nech;   /* length in bytes of ech, 0 means use ch instead of ech */
-    size_t cech;   /* capacity in bytes of ech */
+    uint32_t *ech; /* a grapheme cluster of Unicode code points, 0-terminated */
+    size_t nech;   /* num elements in ech, 0 means use ch instead of ech */
+    size_t cech;   /* num elements allocated for ech */
 #endif
 };
 
@@ -3232,7 +3232,7 @@ static int cell_set(struct tb_cell *cell, uint32_t *ch, size_t nch,
     } else {
         int rv;
         if_err_return(rv, cell_reserve_ech(cell, nch + 1));
-        memcpy(cell->ech, ch, nch);
+        memcpy(cell->ech, ch, sizeof(ch) * nch);
         cell->ech[nch] = '\0';
         cell->nech = nch;
     }
diff --git a/tests/test_egc/expected.ansi b/tests/test_egc/expected.ansi
new file mode 100644
index 0000000..69cda5c
--- /dev/null
+++ b/tests/test_egc/expected.ansi
@@ -0,0 +1,24 @@
+#5aёb
+#5cёd
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/tests/test_egc/test.php b/tests/test_egc/test.php
new file mode 100755
index 0000000..f6a59ff
--- /dev/null
+++ b/tests/test_egc/test.php
@@ -0,0 +1,29 @@
+<?php
+declare(strict_types=1);
+
+if (!$test->ffi->tb_has_egc()) {
+    // This will only work with extended grapheme cluster support
+    $test->skip();
+}
+
+$test->ffi->tb_init();
+
+$ech = $test->ffi->new('uint32_t[2]');
+$test->ffi->tb_utf8_char_to_unicode(FFI::addr($ech[0]), "\xd0\xb5"); // cyrillic small letter ie
+$test->ffi->tb_utf8_char_to_unicode(FFI::addr($ech[1]), "\xcc\x88"); // combining diaeresis
+
+// Set EGC using tb_set_cell_ex
+$y = 0;
+$test->ffi->tb_set_cell(0, $y, ord('a'), 0, 0);
+$test->ffi->tb_set_cell_ex(1, $y, $test->ffi->cast('uint32_t *', FFI::addr($ech)), 2, 0, 0);
+$test->ffi->tb_set_cell(2, $y, ord('b'), 0, 0);
+
+++$y;
+// Same effect with tb_extend_cell
+$test->ffi->tb_set_cell(0, $y, ord('c'), 0, 0);
+$test->ffi->tb_set_cell(1, $y, $ech[0], 0, 0);
+$test->ffi->tb_extend_cell(1, $y, $ech[1]);
+$test->ffi->tb_set_cell(2, $y, ord('d'), 0, 0);
+
+$test->ffi->tb_present();
+$test->screencap();
-- 
2.39.5