Reorganize the codebase

services/libs/jinux-std/src/syscall/setpgid.rs

@@ -0,0 +1,55 @@
+use crate::{
+    log_syscall_entry,
+    prelude::*,
+    process::{
+        process_group::ProcessGroup,
+        process_table::{self, pid_to_process},
+        Pgid, Pid,
+    },
+};
+
+use super::{SyscallReturn, SYS_SETPGID};
+
+pub fn sys_setpgid(pid: Pid, pgid: Pgid) -> Result<SyscallReturn> {
+    log_syscall_entry!(SYS_SETPGID);
+    let current = current!();
+    // if pid is 0, pid should be the pid of current process
+    let pid = if pid == 0 { current.pid() } else { pid };
+    // if pgid is 0, pgid should be pid
+    let pgid = if pgid == 0 { pid } else { pgid };
+    debug!("pid = {}, pgid = {}", pid, pgid);
+
+    if pid != current.pid() && !current.children().lock().contains_key(&pid) {
+        return_errno_with_message!(
+            Errno::ESRCH,
+            "cannot set pgid for process other than current or children of current"
+        );
+    }
+    // FIXME: If pid is child process of current and already calls execve, should return error.
+    // How can we determine a child process has called execve?
+
+    // only can move process to an existing group or self
+    if pgid != pid && process_table::pgid_to_process_group(pgid).is_none() {
+        return_errno_with_message!(Errno::EPERM, "process group must exist");
+    }
+
+    let process =
+        pid_to_process(pid).ok_or(Error::with_message(Errno::ESRCH, "process does not exist"))?;
+
+    // if the process already belongs to the process group
+    if process.pgid() == pgid {
+        return Ok(SyscallReturn::Return(0));
+    }
+
+    if let Some(process_group) = process_table::pgid_to_process_group(pgid) {
+        process_group.add_process(process.clone());
+        process.set_process_group(Arc::downgrade(&process_group));
+    } else {
+        let new_process_group = Arc::new(ProcessGroup::new(process.clone()));
+        // new_process_group.add_process(process.clone());
+        process.set_process_group(Arc::downgrade(&new_process_group));
+        process_table::add_process_group(new_process_group);
+    }
+
+    Ok(SyscallReturn::Return(0))
+}