From 7b38366f956ff97dbe5c6132635764a6ec38542e Mon Sep 17 00:00:00 2001
From: Matthias Kruk <m@m10k.eu>
Date: Mon, 4 Nov 2019 17:35:24 +0900
Subject: [PATCH] Implement process_detach() method, to create a new session
 for a process, i.e. detach it from its parent

---
 include/corax/ipc.h      |  3 +++
 kernel/core/posixcall.c  | 28 +++++++++++++++++++++++++++-
 kernel/core/process.c    | 14 ++++++++++++++
 kernel/include/process.h |  1 +
 4 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/include/corax/ipc.h b/include/corax/ipc.h
index 2e916f4..90b911f 100644
--- a/include/corax/ipc.h
+++ b/include/corax/ipc.h
@@ -15,4 +15,7 @@ struct cxmsg {
 
 #define cm_data CM_dat.CM_data
 
+#define PID_INIT 1
+#define PID_UNIX 10
+
 #endif /* __CORAX_IPC_H */
diff --git a/kernel/core/posixcall.c b/kernel/core/posixcall.c
index 781c889..34b2926 100644
--- a/kernel/core/posixcall.c
+++ b/kernel/core/posixcall.c
@@ -64,7 +64,33 @@ int sys_waitpid(pid_t pid, int *status, int options)
 
 int sys_setsid(void)
 {
-	return(-ENOSYS);
+	process_t *cproc;
+	int ret_val;
+
+	/*
+	 * This call should basically just detach the process from its
+	 * parent, so it can continue after the parent process has ended.
+	 */
+
+	ret_val = -EFAULT;
+	cproc = process_get_current();
+
+	if(cproc) {
+		/*
+		 * At this point there is nothing that needs to be done here. Maybe
+		 * in the future there will be more that needs to be done.
+		 */
+
+#if 0
+		process_t *pproc;
+
+		pproc = process_lookup(cproc->p_pid);
+#endif /* 0 */
+
+		ret_val = process_detach(cproc);
+	}
+
+	return(ret_val);
 }
 
 int sys_posixcall(stack_frame_t *stk)
diff --git a/kernel/core/process.c b/kernel/core/process.c
index cb4699a..a909903 100644
--- a/kernel/core/process.c
+++ b/kernel/core/process.c
@@ -558,3 +558,17 @@ int process_fork(int v)
 
 	return(ret_val);
 }
+
+int process_detach(process_t *proc)
+{
+	int ret_val;
+
+	ret_val = -EINVAL;
+
+	if(proc) {
+		proc->p_pid = PID_INIT;
+		ret_val = 0;
+	}
+
+	return(ret_val);
+}
diff --git a/kernel/include/process.h b/kernel/include/process.h
index 480e2e0..4ac66d2 100644
--- a/kernel/include/process.h
+++ b/kernel/include/process.h
@@ -51,5 +51,6 @@ void*         process_get_tasks(process_t*);
 pid_t         process_get_id(process_t*);
 int           process_exit(process_t*, int);
 int           process_fork(int);
+int           process_detach(process_t*);
 
 #endif /* __PROCESS_H */
-- 
2.47.3