erts: Move os_pid to port hash to child setup

Had to move the hashing because of a race that can otherwise happen
where a new os_pid value was inserted into the hash before the
previous value had been removed.

Also replaced the protocol inbetween erts and child setup to be
a binary protocol. This was done in order to deal with the varying
size of Eterm.

1 files changed, 68 insertions, 0 deletions

diff --git a/erts/emulator/sys/unix/erl_child_setup.h b/erts/emulator/sys/unix/erl_child_setup.h
new file mode 100644
index 0000000000..c3258f7cbe
--- /dev/null
+++ b/erts/emulator/sys/unix/erl_child_setup.h
@@ -0,0 +1,68 @@
+/*
+ * %CopyrightBegin%
+ * 
+ * Copyright Ericsson AB 2015-2015. All Rights Reserved.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * %CopyrightEnd%
+ *
+ * This file defines the interface inbetween erts and child_setup.
+ */
+
+#ifndef _ERL_UNIX_FORKER_H
+#define _ERL_UNIX_FORKER_H
+
+#include "sys.h"
+
+#define FORKER_ARGV_NO_OF_ARGS  3
+#define FORKER_ARGV_PROGNAME_IX	0    /* Program name                          */
+#define FORKER_ARGV_MAX_FILES	1    /* max_files                             */
+
+#define FORKER_FLAG_USE_STDIO   (1 << 0)    /* dup the pipe to stdin/stderr   */
+#define FORKER_FLAG_EXIT_STATUS (1 << 1)    /* send the exit status to parent */
+#define FORKER_FLAG_DO_READ     (1 << 2)    /* dup write fd */
+#define FORKER_FLAG_DO_WRITE    (1 << 3)    /* dup read  fd  */
+
+#if SIZEOF_VOID_P == SIZEOF_LONG
+typedef unsigned long ErtsSysPortId;
+#elif SIZEOF_VOID_P == SIZEOF_INT
+typedef unsigned int ErtsSysPortId;
+#elif SIZEOF_VOID_P == SIZEOF_LONG_LONG
+typedef unsigned long long ErtsSysPortId;
+#endif
+
+typedef struct ErtsSysForkerProto_ {
+    enum {
+        ErtsSysForkerProtoAction_Start,
+        ErtsSysForkerProtoAction_Go,
+        ErtsSysForkerProtoAction_SigChld,
+        ErtsSysForkerProtoAction_Ack
+    } action;
+    union {
+        struct {
+            ErtsSysPortId port_id;
+            int fds[3];
+        } start;
+        struct {
+            pid_t os_pid;
+            int error_number;
+        } go;
+        struct {
+            ErtsSysPortId port_id;
+            int error_number;
+        } sigchld;
+    } u;
+} ErtsSysForkerProto;
+
+#endif /* #ifndef _ERL_UNIX_FORKER_H */