Add stop arguments: fd and is_direct_call

6 files changed, 53 insertions, 49 deletions

diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml
index e7073a962f..94aff7c67b 100644
--- a/erts/doc/src/erl_nif.xml
+++ b/erts/doc/src/erl_nif.xml
@@ -718,10 +718,12 @@ typedef void ErlNifResourceDtor(ErlNifEnv* env, void* obj);</code>
       <tag><marker id="ErlNifResourceStop"/><c>ErlNifResourceStop</c></tag>
       <item>
         <code type="none">
-typedef void ErlNifResourceStop(ErlNifEnv* env, void* obj);</code>
+typedef void ErlNifResourceStop(ErlNifEnv* env, void* obj, ErlNifEvent event, int is_direct_call);</code>
         <p>The function prototype of a resource stop function,
 	  called on the behalf of <seealso marker="#enif_select">
-	  enif_select</seealso>.</p>
+	  enif_select</seealso>. <c>obj</c> is the resource, <c>event</c> is OS event,
+	  <c>is_direct_call</c> is true if the call is made directly from <c>enif_select</c>
+	  or false if it is a scheduled call (potentially from another thread).</p>
       </item>
       <tag><marker id="ErlNifCharEncoding"/><c>ErlNifCharEncoding</c></tag>
       <item>
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 27abba7cfd..4e41944ccb 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -2124,12 +2124,13 @@ static void nif_resource_dtor(Binary* bin)
     }
 }
 
-void erts_resource_stop(ErlNifResource* resource)
+void erts_resource_stop(ErlNifResource* resource, ErlNifEvent e,
+                        int is_direct_call)
 {
     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);
+    resource->type->stop(&msg_env.env, resource->data, e, is_direct_call);
     post_nif_noproc(&msg_env);
 }
 
diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h
index bf0f7b1f15..78e0fa1864 100644
--- a/erts/emulator/beam/erl_nif.h
+++ b/erts/emulator/beam/erl_nif.h
@@ -138,18 +138,18 @@ typedef struct
     void* ref_bin;
 }ErlNifBinary;
 
-typedef struct {
-    void (*dtor)(ErlNifEnv* env, void* obj);
-    void (*stop)(ErlNifEnv* env, void* obj); /* at ERL_NIF_SELECT_STOP event */
-} ErlNifResourceTypeInit;
+//#ifndef ERL_SYS_DRV
+typedef int ErlNifEvent; /* An event to be selected on. */
+//#endif
 
 typedef struct enif_resource_type_t ErlNifResourceType;
 typedef void ErlNifResourceDtor(ErlNifEnv*, void*);
-typedef void ErlNifResourceStop(ErlNifEnv*, void*);
+typedef void ErlNifResourceStop(ErlNifEnv*, void*, ErlNifEvent, int is_direct_call);
 
-//#ifndef ERL_SYS_DRV
-typedef int ErlNifEvent; /* An event to be selected on. */
-//#endif
+typedef struct {
+    ErlNifResourceDtor* dtor;
+    ErlNifResourceStop* stop;  /* at ERL_NIF_SELECT_STOP event */
+} ErlNifResourceTypeInit;
 
 typedef enum
 {
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 5c5693a315..2decb56544 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -95,7 +95,7 @@ extern void erts_pre_dirty_nif(ErtsSchedulerData *,
 			       struct erl_module_nif*);
 extern void erts_post_dirty_nif(struct enif_environment_t* env);
 #endif
-extern void erts_resource_stop(ErlNifResource* resource);
+extern void erts_resource_stop(ErlNifResource*, ErlNifEvent, int is_direct_call);
 extern Eterm erts_nif_taints(Process* p);
 extern void erts_print_nif_taints(fmtfn_t to, void* to_arg);
 void erts_unload_nif(struct erl_module_nif* nif);
diff --git a/erts/emulator/sys/common/erl_check_io.c b/erts/emulator/sys/common/erl_check_io.c
index aeda49b2c6..a533a10c22 100644
--- a/erts/emulator/sys/common/erl_check_io.c
+++ b/erts/emulator/sys/common/erl_check_io.c
@@ -450,7 +450,7 @@ forget_removed(struct pollset_info* psi)
 	    }
 	}
         if (resource) {
-            erts_resource_stop(resource);
+            erts_resource_stop(resource, (ErlNifEvent)fd, 0);
             enif_release_resource(resource->data);
         }
 
@@ -1436,7 +1436,7 @@ done:
 done_unknown:
     erts_smp_mtx_unlock(fd_mtx(fd));
     if (call_stop) {
-        erts_resource_stop(resource);
+        erts_resource_stop(resource, (ErlNifEvent)fd, 1);
         if (call_stop == CALL_STOP_AND_RELEASE) {
             enif_release_resource(resource->data);
         }
@@ -2141,6 +2141,10 @@ ERTS_CIO_EXPORT(erts_check_io_interrupt_timed)(int set,
     ERTS_CIO_POLL_INTR_TMD(pollset.ps, set, timeout_time);
 }
 
+/*
+ * Number of ignored events, for a lingering fd added by enif_select(),
+ * until we deselect fd-event from pollset.
+ */
 #define ERTS_NIF_DELAYED_DESELECT 20
 
 void
diff --git a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
index f6ccd3e6ba..878a9ffda9 100644
--- a/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
+++ b/erts/emulator/test/nif_SUITE_data/nif_SUITE.c
@@ -108,13 +108,14 @@ struct binary_resource {
 
 static ErlNifResourceType* fd_resource_type;
 static void fd_resource_dtor(ErlNifEnv* env, void* obj);
-static void fd_resource_stop(ErlNifEnv* env, void* obj);
+static void fd_resource_stop(ErlNifEnv* env, void* obj, ErlNifEvent, int);
 static ErlNifResourceTypeInit fd_rt_init = {
     fd_resource_dtor,
     fd_resource_stop
 };
 struct fd_resource {
     int fd;
+    int was_selected;
 };
 
 
@@ -1128,10 +1129,6 @@ static ERL_NIF_TERM make_term_string(struct make_term_info* mti, int n)
 {
     return enif_make_string(mti->dst_env, "Hello!", ERL_NIF_LATIN1);
 }
-static ERL_NIF_TERM make_term_ref(struct make_term_info* mti, int n)
-{
-    return enif_make_ref(mti->dst_env);
-}
 static ERL_NIF_TERM make_term_sub_binary(struct make_term_info* mti, int n)
 {
     ERL_NIF_TERM orig;
@@ -1239,7 +1236,6 @@ static Make_term_Func* make_funcs[] = {
     make_term_atom,
     make_term_existing_atom,
     make_term_string,
-    //make_term_ref,
     make_term_sub_binary,
     make_term_uint,
     make_term_long,
@@ -2032,26 +2028,23 @@ static ERL_NIF_TERM format_term(ErlNifEnv* env, int argc, const ERL_NIF_TERM arg
 }
 
 
-static int get_fd(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifEvent* fd)
+static int get_fd(ErlNifEnv* env, ERL_NIF_TERM term, struct fd_resource** rsrc)
 {
-    struct fd_resource* rsrc;
-
-    if (!enif_get_resource(env, term, fd_resource_type, (void**)&rsrc)) {
+    if (!enif_get_resource(env, term, fd_resource_type, (void**)rsrc)) {
         return 0;
     }
-    *fd = rsrc->fd;
     return 1;
 }
 
 static ERL_NIF_TERM select_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
-    ErlNifEvent e;
+    struct fd_resource* fdr;
     enum ErlNifSelectFlags mode;
     void* obj;
     ERL_NIF_TERM ref;
     int retval;
 
-    if (!get_fd(env, argv[0], &e)
+    if (!get_fd(env, argv[0], &fdr)
         || !enif_get_uint(env, argv[1], &mode)
         || !enif_get_resource(env, argv[2], fd_resource_type, &obj))
     {
@@ -2060,7 +2053,8 @@ static ERL_NIF_TERM select_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv
 
     ref = argv[3];
 
-    retval = enif_select(env, e, mode, obj, ref);
+    fdr->was_selected = 1;
+    retval = enif_select(env, fdr->fd, mode, obj, ref);
 
     return enif_make_int(env, retval);
 }
@@ -2070,7 +2064,6 @@ static ERL_NIF_TERM pipe_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]
     struct fd_resource* read_rsrc;
     struct fd_resource* write_rsrc;
     ERL_NIF_TERM read_fd, write_fd;
-    unsigned char *inp, *outp;
     int fds[2], flags;
 
     if (pipe(fds) < 0)
@@ -2099,16 +2092,16 @@ static ERL_NIF_TERM pipe_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]
 
 static ERL_NIF_TERM write_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
-    ErlNifEvent fd;
+    struct fd_resource* fdr;
     ErlNifBinary bin;
     int n, written = 0;
 
-    if (!get_fd(env, argv[0], &fd)
+    if (!get_fd(env, argv[0], &fdr)
         || !enif_inspect_binary(env, argv[1], &bin))
         return enif_make_badarg(env);
 
     for (;;) {
-        n = write(fd, bin.data + written, bin.size - written);
+        n = write(fdr->fd, bin.data + written, bin.size - written);
         if (n >= 0) {
             written += n;
             if (written == bin.size) {
@@ -2129,19 +2122,19 @@ static ERL_NIF_TERM write_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[
 
 static ERL_NIF_TERM read_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
-    ErlNifEvent fd;
+    struct fd_resource* fdr;
     unsigned char* buf;
-    int n, count, nread = 0;
+    int n, count;
     ERL_NIF_TERM res;
 
-    if (!get_fd(env, argv[0], &fd)
+    if (!get_fd(env, argv[0], &fdr)
         || !enif_get_int(env, argv[1], &count) || count < 1)
         return enif_make_badarg(env);
 
     buf = enif_make_new_binary(env, count, &res);
 
     for (;;) {
-        n = read(fd, buf, count);
+        n = read(fdr->fd, buf, count);
         if (n > 0) {
             if (n < count) {
                 res = enif_make_sub_binary(env, res, 0, n);
@@ -2165,29 +2158,33 @@ static ERL_NIF_TERM read_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]
 
 static ERL_NIF_TERM is_closed_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
 {
-    ErlNifEvent fd;
+    struct fd_resource* fdr;
 
-    if (!get_fd(env, argv[0], &fd))
+    if (!get_fd(env, argv[0], &fdr))
         return enif_make_badarg(env);
 
-    return fd < 0 ? atom_true : atom_false;
+    return fdr->fd < 0 ? atom_true : atom_false;
 }
 
 static void fd_resource_dtor(ErlNifEnv* env, void* obj)
 {
-    struct fd_resource* rsrc = (struct fd_resource*)obj;
+    struct fd_resource* fdr = (struct fd_resource*)obj;
     resource_dtor(env, obj);
-    if (rsrc->fd >= 0)
-        close(rsrc->fd);
+    if (fdr->fd >= 0) {
+        assert(!fdr->was_selected);
+        close(fdr->fd);
+    }
 }
 
-static void fd_resource_stop(ErlNifEnv* env, void* obj)
+static void fd_resource_stop(ErlNifEnv* env, void* obj, ErlNifEvent fd,
+                             int is_direct_call)
 {
-    struct fd_resource* rsrc = (struct fd_resource*)obj;
-    if (rsrc->fd >= 0) {
-        close(rsrc->fd);
-        rsrc->fd = -1;   /* thread safety ? */
-    }
+    struct fd_resource* fdr = (struct fd_resource*)obj;
+    assert(fd == fdr->fd);
+    assert(fd >= 0);
+    close(fd);
+    fdr->fd = -1;   /* thread safety ? */
+    fdr->was_selected = 0;
 }