Merge pull request #6263 from opensourcerouting/zlog-coverity-20200420

[mirror_frr.git] / lib / hook.h

diff --git a/lib/hook.h b/lib/hook.h
index 5f45e113e75cbca264159b7d023c3d51735190e3..3823cebe6ac563025d0fce654e5c4ac51df0fb21 100644 (file)
--- a/lib/hook.h
+++ b/lib/hook.h
@@ -1,23 +1,17 @@
 /*
  * Copyright (c) 2016  David Lamparter, for NetDEF, Inc.
  *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 #ifndef _FRR_HOOK_H
@@ -28,6 +22,10 @@
 #include "module.h"
 #include "memory.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* type-safe subscribable hook points
  *
  * where "type-safe" applies to the function pointers used for subscriptions
@@ -116,7 +114,9 @@ struct hookent {
        struct hookent *next;
        void *hookfn; /* actually a function pointer */
        void *hookarg;
-       bool has_arg;
+       bool has_arg : 1;
+       bool ent_on_heap : 1;
+       bool ent_used : 1;
        int priority;
        struct frrmod_runtime *module;
        const char *fnname;
@@ -135,23 +135,35 @@ struct hook {
  * always use hook_register(), which uses the static inline helper from
  * DECLARE_HOOK in order to get type safety
  */
-extern void _hook_register(struct hook *hook, void *funcptr, void *arg,
-                          bool has_arg, struct frrmod_runtime *module,
+extern void _hook_register(struct hook *hook, struct hookent *stackent,
+                          void *funcptr, void *arg, bool has_arg,
+                          struct frrmod_runtime *module,
                           const char *funcname, int priority);
+
+/* most hook_register calls are not in a loop or similar and can use a
+ * statically allocated "struct hookent" from the data segment
+ */
+#define _hook_reg_svar(hook, funcptr, arg, has_arg, module, funcname, prio)    \
+       do {                                                                   \
+               static struct hookent stack_hookent = { .ent_on_heap = 0, };   \
+               _hook_register(hook, &stack_hookent, funcptr, arg, has_arg,    \
+                              module, funcname, prio);                        \
+       } while (0)
+
 #define hook_register(hookname, func)                                          \
-       _hook_register(&_hook_##hookname, _hook_typecheck_##hookname(func),    \
+       _hook_reg_svar(&_hook_##hookname, _hook_typecheck_##hookname(func),    \
                       NULL, false, THIS_MODULE, #func, HOOK_DEFAULT_PRIORITY)
 #define hook_register_arg(hookname, func, arg)                                 \
-       _hook_register(&_hook_##hookname,                                      \
+       _hook_reg_svar(&_hook_##hookname,                                      \
                       _hook_typecheck_arg_##hookname(func), arg, true,        \
                       THIS_MODULE, #func, HOOK_DEFAULT_PRIORITY)
 #define hook_register_prio(hookname, prio, func)                               \
-       _hook_register(&_hook_##hookname, _hook_typecheck_##hookname(func),    \
+       _hook_reg_svar(&_hook_##hookname, _hook_typecheck_##hookname(func),    \
                       NULL, false, THIS_MODULE, #func, prio)
 #define hook_register_arg_prio(hookname, prio, func, arg)                      \
-       _hook_register(&_hook_##hookname,                                      \
-                      _hook_typecheck_arg_##hookname(func),                   \
-                      arg, true, THIS_MODULE, #func, prio)
+       _hook_reg_svar(&_hook_##hookname,                                      \
+                      _hook_typecheck_arg_##hookname(func), arg, true,        \
+                      THIS_MODULE, #func, prio)
 
 extern void _hook_unregister(struct hook *hook, void *funcptr, void *arg,
                             bool has_arg);
@@ -190,7 +202,7 @@ extern void _hook_unregister(struct hook *hook, void *funcptr, void *arg,
        {                                                                      \
                return (void *)funcptr;                                        \
        }
-#define DECLARE_KOOH(hookname, arglist, passlist) \
+#define DECLARE_KOOH(hookname, arglist, passlist)                              \
        DECLARE_HOOK(hookname, arglist, passlist)
 
 /* use in source file - contains hook-related definitions.
@@ -220,9 +232,13 @@ extern void _hook_unregister(struct hook *hook, void *funcptr, void *arg,
                return hooksum;                                                \
        }
 
-#define DEFINE_HOOK(hookname, arglist, passlist) \
+#define DEFINE_HOOK(hookname, arglist, passlist)                               \
        DEFINE_HOOK_INT(hookname, arglist, passlist, false)
-#define DEFINE_KOOH(hookname, arglist, passlist) \
+#define DEFINE_KOOH(hookname, arglist, passlist)                               \
        DEFINE_HOOK_INT(hookname, arglist, passlist, true)
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _FRR_HOOK_H */