use nix build & meson & zlog

src/include/hook.h

@@ -0,0 +1,30 @@
+#if !defined(__HOOK_H__)
+
+#define __HOOK_H__ 1
+
+#include <stdarg.h>
+#include <stddef.h>
+
+#include "xlist.h"
+
+#define HOOK_BEFORE_EVENT (0)
+#define HOOK_AFTER_EVENT  (1)
+
+typedef int (*hook_fn_t)(int, int, int, void*, va_list);
+typedef struct {
+    hook_fn_t fn;
+    void*     data;
+} hook_item_t;
+
+typedef struct {
+    int      maxtypes;
+    xlist_t* hooks;
+} hooksys_t;
+
+extern int  xce_hook_init(hooksys_t*, int);
+extern int  xce_add_hook(hooksys_t*, int,
+                         hook_fn_t, void*);
+extern int  xce_run_hooks(hooksys_t*, int, int, int, ...);
+extern void xce_hook_fini(hooksys_t*);
+
+#endif