Fixing isolated process PID manipulation.

Registering an isolated PID in the global PID hash is wrong
because it can be duplicated.  Isolated processes are stored only
in the children list until the response for the WHOAMI message is
processed and the global PID is discovered.

To remove isolated siblings, a pointer to the children list is
introduced in the nxt_process_init_t struct.

This closes #633 issue on GitHub.

1 files changed, 31 insertions, 3 deletions

diff --git a/src/nxt_process.c b/src/nxt_process.c
index 98636bbe..738a03bf 100644
--- a/src/nxt_process.c
+++ b/src/nxt_process.c
@@ -296,6 +296,16 @@ nxt_process_child_fixup(nxt_task_t *task, nxt_process_t *process)
 
     } nxt_runtime_process_loop;
 
+    if (init->siblings != NULL) {
+        nxt_queue_each(p, init->siblings, nxt_process_t, link) {
+
+            nxt_debug(task, "remove sibling process %PI", p->pid);
+
+            nxt_process_close_ports(task, p);
+
+        } nxt_queue_loop;
+    }
+
     return NXT_OK;
 }
 
@@ -303,8 +313,9 @@ nxt_process_child_fixup(nxt_task_t *task, nxt_process_t *process)
 static nxt_pid_t
 nxt_process_create(nxt_task_t *task, nxt_process_t *process)
 {
-    nxt_int_t           ret;
-    nxt_pid_t           pid;
+    nxt_int_t      ret;
+    nxt_pid_t      pid;
+    nxt_runtime_t  *rt;
 
 #if (NXT_HAVE_CLONE)
     pid = nxt_clone(SIGCHLD | process->isolation.clone.flags);
@@ -352,7 +363,20 @@ nxt_process_create(nxt_task_t *task, nxt_process_t *process)
     process->pid = pid;
     process->isolated_pid = pid;
 
-    nxt_runtime_process_add(task, process);
+    rt = task->thread->runtime;
+
+    if (rt->is_pid_isolated) {
+        /*
+         * Do not register process in runtime with isolated pid.
+         * Only global pid can be the key to avoid clash.
+         */
+        nxt_assert(!nxt_queue_is_empty(&process->ports));
+
+        nxt_port_use(task, nxt_process_port_first(process), 1);
+
+    } else {
+        nxt_runtime_process_add(task, process);
+    }
 
     return pid;
 }
@@ -960,6 +984,8 @@ nxt_process_close_ports(nxt_task_t *task, nxt_process_t *process)
 {
     nxt_port_t  *port;
 
+    nxt_process_use(task, process, 1);
+
     nxt_process_port_each(process, port) {
 
         nxt_port_close(task, port);
@@ -967,6 +993,8 @@ nxt_process_close_ports(nxt_task_t *task, nxt_process_t *process)
         nxt_runtime_port_remove(task, port);
 
     } nxt_process_port_loop;
+
+    nxt_process_use(task, process, -1);
 }