From 0763a36867a702e3075b682973a079e0390144ce Mon Sep 17 00:00:00 2001
From: Sverker Eriksson <sverker@erlang.org>
Date: Wed, 23 Nov 2016 15:58:15 +0100
Subject: erts: Add enif_select & enif_open_resource_type_x

---
 erts/emulator/beam/erl_nif.c | 90 +++++++++++++++++++++++++-------------------
 1 file changed, 52 insertions(+), 38 deletions(-)

(limited to 'erts/emulator/beam/erl_nif.c')

diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 202f713f67..27abba7cfd 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -1904,37 +1904,10 @@ int enif_snprintf(char *buffer, size_t size, const char* format, ...)
  **       Memory managed (GC'ed) "resource" objects       **
  ***********************************************************/
 
-
-struct enif_resource_type_t
-{
-    struct enif_resource_type_t* next;   /* list of all resource types */
-    struct enif_resource_type_t* prev;    
-    struct erl_module_nif* owner;  /* that created this type and thus implements the destructor*/
-    ErlNifResourceDtor* dtor;      /* user destructor function */
-    erts_refc_t refc;  /* num of resources of this type (HOTSPOT warning)
-                          +1 for active erl_module_nif */
-    Eterm module;
-    Eterm name;
-};
-
 /* dummy node in circular list */
 struct enif_resource_type_t resource_type_list; 
 
-typedef struct enif_resource_t
-{
-    struct enif_resource_type_t* type;
-#ifdef DEBUG
-    erts_refc_t nif_refc;
-# ifdef ARCH_32
-    byte align__[4];
-# endif
-#endif
-
-    char data[1];
-}ErlNifResource;
-
 #define SIZEOF_ErlNifResource(SIZE) (offsetof(ErlNifResource,data) + (SIZE))
-#define DATA_TO_RESOURCE(PTR) ((ErlNifResource*)((char*)(PTR) - offsetof(ErlNifResource,data)))
 
 static ErlNifResourceType* find_resource_type(Eterm module, Eterm name)
 {
@@ -1997,24 +1970,23 @@ struct opened_resource_type
 
     ErlNifResourceFlags op;
     ErlNifResourceType* type;
-    ErlNifResourceDtor* new_dtor;
+    ErlNifResourceTypeInit new_callbacks;
 };
 static struct opened_resource_type* opened_rt_list = NULL;
 
-ErlNifResourceType*
-enif_open_resource_type(ErlNifEnv* env,
-			const char* module_str, 
-			const char* name_str, 
-			ErlNifResourceDtor* dtor,
-			ErlNifResourceFlags flags,
-			ErlNifResourceFlags* tried)
+static
+ErlNifResourceType* open_resource_type(ErlNifEnv* env,
+                                       const char* name_str,
+                                       const ErlNifResourceTypeInit* init,
+                                       ErlNifResourceFlags flags,
+                                       ErlNifResourceFlags* tried,
+                                       size_t sizeof_init)
 {
     ErlNifResourceType* type = NULL;
     ErlNifResourceFlags op = flags;
     Eterm module_am, name_am;
 
     ASSERT(erts_smp_thr_progress_is_blocking());
-    ASSERT(module_str == NULL); /* for now... */
     module_am = make_atom(env->mod_nif->mod->module);
     name_am = enif_make_atom(env, name_str);
 
@@ -2048,7 +2020,9 @@ enif_open_resource_type(ErlNifEnv* env,
 						sizeof(struct opened_resource_type));
 	ort->op = op;
 	ort->type = type;
-	ort->new_dtor = dtor;
+        sys_memzero(&ort->new_callbacks, sizeof(ErlNifResourceTypeInit));
+        ASSERT(sizeof_init > 0 && sizeof_init <= sizeof(ErlNifResourceTypeInit));
+        sys_memcpy(&ort->new_callbacks, init, sizeof_init);
 	ort->next = opened_rt_list;
 	opened_rt_list = ort;
     }
@@ -2058,6 +2032,31 @@ enif_open_resource_type(ErlNifEnv* env,
     return type;
 }
 
+ErlNifResourceType*
+enif_open_resource_type(ErlNifEnv* env,
+                        const char* module_str,
+                        const char* name_str,
+			ErlNifResourceDtor* dtor,
+			ErlNifResourceFlags flags,
+			ErlNifResourceFlags* tried)
+{
+    ErlNifResourceTypeInit init =  {dtor, NULL};
+    ASSERT(module_str == NULL); /* for now... */
+    return open_resource_type(env, name_str, &init, flags, tried,
+                              sizeof(init));
+}
+
+ErlNifResourceType*
+enif_open_resource_type_x(ErlNifEnv* env,
+                          const char* name_str,
+                          const ErlNifResourceTypeInit* init,
+                          ErlNifResourceFlags flags,
+                          ErlNifResourceFlags* tried)
+{
+    return open_resource_type(env, name_str, init, flags, tried,
+                              env->mod_nif->entry.sizeof_ErlNifResourceTypeInit);
+}
+
 static void commit_opened_resource_types(struct erl_module_nif* lib)
 {
     while (opened_rt_list) {
@@ -2076,7 +2075,8 @@ static void commit_opened_resource_types(struct erl_module_nif* lib)
 	}
 
 	type->owner = lib;
-	type->dtor = ort->new_dtor;
+	type->dtor = ort->new_callbacks.dtor;
+        type->stop = ort->new_callbacks.stop;
 
 	if (type->dtor != NULL) {
 	    erts_refc_inc(&lib->rt_dtor_cnt, 1);
@@ -2124,6 +2124,15 @@ static void nif_resource_dtor(Binary* bin)
     }
 }
 
+void erts_resource_stop(ErlNifResource* resource)
+{
+    struct enif_msg_environment_t msg_env;
+    ASSERT(resource->type->stop);
+    pre_nif_noproc(&msg_env, resource->type->owner, NULL);
+    resource->type->stop(&msg_env.env, resource->data);
+    post_nif_noproc(&msg_env);
+}
+
 void* enif_alloc_resource(ErlNifResourceType* type, size_t size)
 {
     Binary* bin = erts_create_magic_binary_x(SIZEOF_ErlNifResource(size),
@@ -3174,6 +3183,11 @@ static struct erl_module_nif* create_lib(const ErlNifEntry* src)
         dst->funcs = lib->_funcs_copy_;
         dst->options = 0;
     }
+    if (AT_LEAST_VERSION(src, 2, 12)) {
+        dst->sizeof_ErlNifResourceTypeInit = src->sizeof_ErlNifResourceTypeInit;
+    } else {
+        dst->sizeof_ErlNifResourceTypeInit = 0;
+    }
     return lib;
 };
 
-- 
cgit v1.2.3