Merge branch 'nybek/fix_gen_tcp_shutdown'

OTP-12797

2 files changed, 56 insertions, 23 deletions

diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c
index 5196eb51c6..e001f31932 100644
--- a/erts/emulator/drivers/common/inet_drv.c
+++ b/erts/emulator/drivers/common/inet_drv.c
@@ -293,6 +293,10 @@ static BOOL (WINAPI *fpSetHandleInformation)(HANDLE,DWORD,DWORD);
 static unsigned long zero_value = 0;
 static unsigned long one_value = 1;
 
+#define TCP_SHUT_WR    SD_SEND
+#define TCP_SHUT_RD    SD_RECEIVE
+#define TCP_SHUT_RDWR  SD_BOTH
+
 #elif defined (__OSE__)
 
 /*
@@ -421,6 +425,10 @@ typedef unsigned long  u_long;
         inet_driver_select((d), (flags), (onoff)); \
    } while(0)
 
+#define TCP_SHUT_WR    SHUT_WR
+#define TCP_SHUT_RD    SHUT_RD
+#define TCP_SHUT_RDWR  SHUT_RDWR
+
 #else /* !__OSE__ && !__WIN32__ */
 
 #include <sys/time.h>
@@ -691,6 +699,9 @@ static int my_strncasecmp(const char *s1, const char *s2, size_t n)
         inet_driver_select((d)->port, (ErlDrvEvent)(long)(d)->event, (flags), (onoff)); \
    } while(0)
 
+#define TCP_SHUT_WR    SHUT_WR
+#define TCP_SHUT_RD    SHUT_RD
+#define TCP_SHUT_RDWR  SHUT_RDWR
 
 #endif /* !__WIN32__ && !__OSE__ */
 
@@ -820,6 +831,10 @@ static int my_strncasecmp(const char *s1, const char *s2, size_t n)
 #define TCP_ADDF_CLOSE_SENT    2 /* Close sent (active mode only) */
 #define TCP_ADDF_DELAYED_CLOSE_RECV 4 /* If receive fails, report {error,closed} (passive mode) */
 #define TCP_ADDF_DELAYED_CLOSE_SEND 8 /* If send fails, report {error,closed} (passive mode) */
+#define TCP_ADDF_PENDING_SHUT_WR   16 /* Call shutdown(sock, SHUT_WR) when queue empties */
+#define TCP_ADDF_PENDING_SHUT_RDWR 32 /* Call shutdown(sock, SHUT_RDWR) when queue empties */
+#define TCP_ADDF_PENDING_SHUTDOWN \
+		(TCP_ADDF_PENDING_SHUT_WR | TCP_ADDF_PENDING_SHUT_RDWR)
 
 /* *_REQ_* replies */
 #define INET_REP_ERROR       0
@@ -1407,6 +1422,8 @@ static int tcp_sendv(tcp_descriptor* desc, ErlIOVec* ev);
 static int tcp_recv(tcp_descriptor* desc, int request_len);
 static int tcp_deliver(tcp_descriptor* desc, int len);
 
+static int tcp_shutdown_error(tcp_descriptor* desc, int err);
+
 static int tcp_inet_output(tcp_descriptor* desc, HANDLE event);
 static int tcp_inet_input(tcp_descriptor* desc, HANDLE event);
 
@@ -9473,10 +9490,18 @@ static ErlDrvSSizeT tcp_inet_ctl(ErlDrvData e, unsigned int cmd,
 	    return ctl_error(EINVAL, rbuf, rsize);
 	}
 	how = buf[0];
-	if (sock_shutdown(INETP(desc)->s, how) == 0) {
+	if (how != TCP_SHUT_RD && driver_sizeq(desc->inet.port) > 0) {
+	    if (how == TCP_SHUT_WR) {
+		desc->tcp_add_flags |= TCP_ADDF_PENDING_SHUT_WR;
+	    } else if (how == TCP_SHUT_RDWR) {
+		desc->tcp_add_flags |= TCP_ADDF_PENDING_SHUT_RDWR;
+	    }
 	    return ctl_reply(INET_REP_OK, NULL, 0, rbuf, rsize);
-	} else {
+	}
+	if (IS_SOCKET_ERROR(sock_shutdown(INETP(desc)->s, how))) {
 	    return ctl_error(sock_errno(), rbuf, rsize);
+	} else {
+	    return ctl_reply(INET_REP_OK, NULL, 0, rbuf, rsize);
 	}
     }
     default:
@@ -9613,6 +9638,8 @@ static void tcp_inet_commandv(ErlDrvData e, ErlIOVec* ev)
 	else
 	    inet_reply_error(INETP(desc), ENOTCONN);
     }
+    else if (desc->tcp_add_flags & TCP_ADDF_PENDING_SHUTDOWN)
+	tcp_shutdown_error(desc, EPIPE);
     else if (tcp_sendv(desc, ev) == 0)
 	inet_reply_ok(INETP(desc));
     DEBUGF(("tcp_inet_commandv(%ld) }\r\n", (long)desc->inet.port)); 
@@ -10506,7 +10533,7 @@ static int tcp_inet_input(tcp_descriptor* desc, HANDLE event)
     return ret;
 }
 
-static int tcp_send_error(tcp_descriptor* desc, int err)
+static int tcp_send_or_shutdown_error(tcp_descriptor* desc, int err)
 {
     /*
      * If the port is busy, we must do some clean-up before proceeding.
@@ -10563,6 +10590,16 @@ static int tcp_send_error(tcp_descriptor* desc, int err)
     return -1;
 }
 
+static int tcp_send_error(tcp_descriptor* desc, int err)
+{
+    return tcp_send_or_shutdown_error(desc, err);
+}
+
+static int tcp_shutdown_error(tcp_descriptor* desc, int err)
+{
+    return tcp_send_or_shutdown_error(desc, err);
+}
+
 /*
 ** Send non-blocking vector data
 */
@@ -10763,6 +10800,19 @@ static int tcp_send(tcp_descriptor* desc, char* ptr, ErlDrvSizeT len)
     return 0;
 }
 
+/* shutdown on the socket:
+** Assume caller has confirmed TCP_ADDF_PENDING_SHUTDOWN is set.
+*/
+static void tcp_shutdown_async(tcp_descriptor* desc)
+{
+    int how;
+
+    how = (desc->tcp_add_flags & TCP_ADDF_PENDING_SHUT_WR) ?
+		TCP_SHUT_WR : TCP_SHUT_RDWR;
+    if (IS_SOCKET_ERROR(sock_shutdown(INETP(desc)->s, how)))
+	tcp_shutdown_error(desc, sock_errno());
+}
+
 #ifdef __OSE__
 
 static void tcp_inet_drv_output_ose(ErlDrvData data, ErlDrvEvent event)
@@ -10891,6 +10941,8 @@ static int tcp_inet_output(tcp_descriptor* desc, HANDLE event)
 	    if ((iov = driver_peekq(ix, &vsize)) == NULL) {
 		sock_select(INETP(desc), FD_WRITE, 0);
 		send_empty_out_q_msgs(INETP(desc));
+		if (desc->tcp_add_flags & TCP_ADDF_PENDING_SHUTDOWN)
+		    tcp_shutdown_async(desc);
 		goto done;
 	    }
 	    vsize = vsize > MAX_VSIZE ? MAX_VSIZE : vsize;
diff --git a/erts/preloaded/src/prim_inet.erl b/erts/preloaded/src/prim_inet.erl
index 79ff013c77..622e1be869 100644
--- a/erts/preloaded/src/prim_inet.erl
+++ b/erts/preloaded/src/prim_inet.erl
@@ -127,37 +127,18 @@ drv2protocol(_)           -> undefined.
 %% TODO: shutdown equivalent for SCTP
 %%
 shutdown(S, read) when is_port(S) ->
-    shutdown_2(S, 0);
+    shutdown_1(S, 0);
 shutdown(S, write) when is_port(S) ->
     shutdown_1(S, 1);
 shutdown(S, read_write) when is_port(S) ->
     shutdown_1(S, 2).
 
 shutdown_1(S, How) ->
-    case subscribe(S, [subs_empty_out_q]) of
-	{ok,[{subs_empty_out_q,N}]} when N > 0 ->
-	    shutdown_pend_loop(S, N);   %% wait for pending output to be sent
-	_Other -> ok
-    end,
-    shutdown_2(S, How).
-
-shutdown_2(S, How) ->
     case ctl_cmd(S, ?TCP_REQ_SHUTDOWN, [How]) of
 	{ok, []} -> ok;
 	{error,_}=Error -> Error
     end.
 
-shutdown_pend_loop(S, N0) ->
-    receive
-	{empty_out_q,S} -> ok
-    after ?INET_CLOSE_TIMEOUT ->
-	    case getstat(S, [send_pend]) of
-                {ok,[{send_pend,N0}]} -> ok;
-                {ok,[{send_pend,N}]} -> shutdown_pend_loop(S, N);
-		_ -> ok
-	    end
-    end.
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%
 %% CLOSE(insock()) -> ok