support running shebang executables

src/services/libs/jinux-std/src/lib.rs

@@ -25,11 +25,6 @@ use crate::{
 };
 use process::Process;
 
-use crate::process::{
-    process_filter::ProcessFilter,
-    wait::{wait_child_exit, WaitOptions},
-};
-
 extern crate alloc;
 extern crate lru;
 #[macro_use]

src/services/libs/jinux-std/src/process/mod.rs

@@ -11,14 +11,15 @@ use self::signal::sig_queues::SigQueues;
 use self::signal::signals::kernel::KernelSignal;
 use self::status::ProcessStatus;
 use crate::fs::file_table::FileTable;
-use crate::fs::fs_resolver::FsResolver;
+use crate::fs::fs_resolver::{FsPath, FsResolver};
+use crate::fs::utils::AccessMode;
 use crate::prelude::*;
 use crate::rights::Full;
 use crate::thread::{thread_table, Thread};
 use crate::tty::get_n_tty;
 use crate::vm::vmar::Vmar;
+use alloc::string::String;
 use jinux_frame::sync::WaitQueue;
-use jinux_frame::task::Task;
 
 pub mod clone;
 pub mod elf;
@@ -386,3 +387,77 @@ impl Process {
 pub fn get_init_process() -> Option<Arc<Process>> {
     process_table::pid_to_process(INIT_PROCESS_PID)
 }
+
+/// Set up root vmar for an executable.
+/// About recursion_limit: recursion limit is used to limit th recursion depth of shebang executables.
+/// If the interpreter program(the program behind !#) of shebang executable is also a shebang,
+/// then it will trigger recursion. We will try to setup root vmar for the interpreter program.
+/// I guess for most cases, setting the recursion_limit as 1 should be enough.
+/// because the interpreter game is usually an elf binary(e.g., /bin/bash)
+pub fn setup_root_vmar(
+    executable_path: String,
+    argv: Vec<CString>,
+    envp: Vec<CString>,
+    fs_resolver: &FsResolver,
+    root_vmar: Vmar<Full>,
+    recursion_limit: usize,
+) -> Result<()> {
+    use crate::fs::fs_resolver::AT_FDCWD;
+    let fs_path = FsPath::new(AT_FDCWD, &executable_path)?;
+    let file = fs_resolver.open(&fs_path, AccessMode::O_RDONLY as u32, 0)?;
+    // read the first page of file header
+    let mut file_header_buffer = [0u8; PAGE_SIZE];
+    file.read(&mut file_header_buffer)?;
+    if recursion_limit > 0
+        && file_header_buffer.starts_with(b"!#")
+        && file_header_buffer.contains(&b'\n')
+    {
+        return set_up_root_vmar_for_shebang(
+            argv,
+            envp,
+            &file_header_buffer,
+            fs_resolver,
+            root_vmar,
+            recursion_limit,
+        );
+    }
+
+    todo!()
+}
+
+fn set_up_root_vmar_for_shebang(
+    argv: Vec<CString>,
+    envp: Vec<CString>,
+    file_header_buffer: &[u8],
+    fs_resolver: &FsResolver,
+    root_vmar: Vmar<Full>,
+    recursion_limit: usize,
+) -> Result<()> {
+    let first_line_len = file_header_buffer.iter().position(|&c| c == b'\n').unwrap();
+    // skip !#
+    let shebang_header = &file_header_buffer[2..first_line_len];
+    let mut shebang_argv = Vec::new();
+    for arg in shebang_header.split(|&c| c == b' ') {
+        let arg = CString::new(arg)?;
+        shebang_argv.push(arg);
+    }
+    if shebang_argv.len() != 1 {
+        return_errno_with_message!(
+            Errno::EINVAL,
+            "One and only one intpreter program should be specified"
+        );
+    }
+    for origin_arg in argv.into_iter() {
+        shebang_argv.push(origin_arg);
+    }
+    use alloc::string::ToString;
+    let shebang_path = shebang_argv[0].to_str()?.to_string();
+    setup_root_vmar(
+        shebang_path,
+        shebang_argv,
+        envp,
+        fs_resolver,
+        root_vmar,
+        recursion_limit - 1,
+    )
+}

src/services/libs/jinux-std/src/thread/kernel_thread.rs

@@ -4,14 +4,12 @@ use crate::prelude::*;
 
 use super::{allocate_tid, status::ThreadStatus, thread_table, Thread};
 
-/// This struct is used to mark a thread is a kernel thread
+/// The inner data of a kernel thread
 pub struct KernelThread;
 
 pub trait KernelThreadExt {
-    /// whether the thread is a kernel thread
-    fn is_kernel_thread(&self) -> bool;
     /// get the kernel_thread structure
-    fn kernel_thread(&self) -> &KernelThread;
+    fn as_kernel_thread(&self) -> Option<&KernelThread>;
     /// create a new kernel thread structure, **NOT** run the thread.
     fn new_kernel_thread<F>(task_fn: F) -> Arc<Thread>
     where
@@ -30,12 +28,8 @@ pub trait KernelThreadExt {
 }
 
 impl KernelThreadExt for Thread {
-    fn is_kernel_thread(&self) -> bool {
-        self.data().downcast_ref::<KernelThread>().is_some()
-    }
-
-    fn kernel_thread(&self) -> &KernelThread {
-        self.data().downcast_ref::<KernelThread>().unwrap()
+    fn as_kernel_thread(&self) -> Option<&KernelThread> {
+        self.data().downcast_ref::<KernelThread>()
     }
 
     fn new_kernel_thread<F>(task_fn: F) -> Arc<Self>