misc/mp_assert: add mp_assert and mp_require macros

misc/mp_assert.h

@@ -0,0 +1,57 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+/**
+ * @brief This file provides two macros, mp_assert and mp_require, used to check
+ * for conditions that should never occur.
+ *
+ * The mp_assert macro is a convenience wrapper around the standard assert,
+ * which also sinks unused variables to prevent compiler warnings. It should be
+ * used for debugging purposes only to check for conditions that should never
+ * occur. This macro can be disabled in release builds by defining NDEBUG and
+ * should not be used for error handling.
+ *
+ * The mp_require macro is similar to mp_assert but more strict. It enforces
+ * critical assertions even in release builds. If the condition is not met, this
+ * macro will abort the program, making it suitable for error handling in cases
+ * where recovery is impossible. Note that this macro does not log any messages
+ * to keep as small footprint as possible in NDEBUG builds.
+ */
+
+#ifndef NDEBUG
+
+#include <assert.h>
+
+#define mp_assert assert
+#define mp_require assert
+
+#else
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#define mp_require(expr)                                       \
+    do {                                                       \
+        if (!(expr))                                           \
+            abort();                                           \
+    } while (0)
+
+#define mp_assert(expr) do { (void)sizeof(expr);} while (0)
+
+#endif