Fix forking and sys_dup2, implement sys_getsockopt and update sys_exec

kernel/src/arch/x86_64/interrupt/trapframe.rs

@@ -181,6 +181,8 @@ impl Context {
             tf: {
                 let mut tf = tf.clone();
                 tf.rax = 0;
+                // skip syscall inst;
+                tf.rip = tf.rip + 2;
                 tf
             },
         }.push_at(kstack_top)

kernel/src/process/structs.rs

@@ -1,4 +1,5 @@
 use alloc::{boxed::Box, collections::BTreeMap, string::String, sync::Arc, vec::Vec};
+use core::fmt;
 
 use log::*;
 use rcore_fs::vfs::INode;
@@ -43,6 +44,15 @@ pub enum FileLike {
     Socket(SocketWrapper)
 }
 
+impl fmt::Debug for FileLike {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            FileLike::File(_) => write!(f, "File"),
+            FileLike::Socket(_) => write!(f, "Socket"),
+        }
+    }
+}
+
 pub struct Process {
     pub memory_set: MemorySet,
     pub files: BTreeMap<usize, FileLike>,

kernel/src/syscall/fs.rs

@@ -27,6 +27,7 @@ pub fn sys_write(fd: usize, base: *const u8, len: usize) -> SysResult {
     info!("write: fd: {}, base: {:?}, len: {:#x}", fd, base, len);
     let mut proc = process();
     proc.memory_set.check_array(base, len)?;
+
     match proc.files.get(&fd) {
         Some(FileLike::File(_)) => sys_write_file(&mut proc, fd, base, len),
         Some(FileLike::Socket(_)) => sys_write_socket(&mut proc, fd, base, len),
@@ -300,9 +301,13 @@ pub fn sys_open(path: *const u8, flags: usize, mode: usize) -> SysResult {
 pub fn sys_close(fd: usize) -> SysResult {
     info!("close: fd: {:?}", fd);
     let mut proc = process();
+    sys_close_internal(&mut proc, fd)
+}
+
+fn sys_close_internal(proc: &mut Process, fd: usize) -> SysResult {
     match proc.files.remove(&fd) {
         Some(FileLike::File(_)) => Ok(0),
-        Some(FileLike::Socket(wrapper)) => sys_close_socket(&mut proc, fd, wrapper.handle),
+        Some(FileLike::Socket(wrapper)) => sys_close_socket(proc, fd, wrapper.handle),
         None => Err(SysError::EINVAL),
     }
 }
@@ -415,11 +420,22 @@ pub fn sys_dup2(fd1: usize, fd2: usize) -> SysResult {
     info!("dup2: {} {}", fd1, fd2);
     let mut proc = process();
     if proc.files.contains_key(&fd2) {
-        return Err(SysError::EINVAL);
+        // close fd2 first if it is opened
+        sys_close_internal(&mut proc, fd2)?;
+    }
+
+    match proc.files.get(&fd1) {
+        Some(FileLike::File(file)) => {
+            let new_file = FileLike::File(file.clone());
+            proc.files.insert(fd2, new_file);
+            Ok(fd2 as isize)
+        },
+        Some(FileLike::Socket(wrapper)) => {
+            let new_wrapper = wrapper.clone();
+            sys_dup2_socket(&mut proc, new_wrapper, fd2)
+        },
+        None => Err(SysError::EINVAL)
     }
-    let file = proc.get_file(fd1)?.clone();
-    proc.files.insert(fd2, FileLike::File(file));
-    Ok(0)
 }
 
 pub fn sys_chdir(path: *const u8) -> SysResult {

kernel/src/syscall/mod.rs

@@ -68,12 +68,12 @@ pub fn syscall(id: usize, args: [usize; 6], tf: &mut TrapFrame) -> isize {
         050 => sys_listen(args[0], args[1]),
         051 => sys_getsockname(args[0], args[1] as *mut u8, args[2] as *mut u32),
         054 => sys_setsockopt(args[0], args[1], args[2], args[3] as *const u8, args[4]),
-//        055 => sys_getsockopt(),
+        055 => sys_getsockopt(args[0], args[1], args[2], args[3] as *mut u8, args[4] as *mut u32),
 //        056 => sys_clone(),
         057 => sys_fork(tf),
         // use fork for vfork
         058 => sys_fork(tf),
-        059 => sys_exec(args[0] as *const u8, args[1] as usize, args[2] as *const *const u8, tf),
+        059 => sys_exec(args[0] as *const u8, args[1] as *const *const u8, args[2] as *const *const u8, tf),
         060 => sys_exit(args[0] as isize),
         061 => sys_wait(args[0], args[1] as *mut i32), // TODO: wait4
         062 => sys_kill(args[0]),
@@ -222,6 +222,7 @@ pub enum SysError {
     ENOSYS = 38,
     ENOTEMPTY = 39,
     ENOTSOCK = 80,
+    ENOPROTOOPT = 92,
     EPFNOSUPPORT = 96,
     EAFNOSUPPORT = 97,
     ENOBUFS = 105,

kernel/src/syscall/net.rs

@@ -148,6 +148,21 @@ pub fn sys_setsockopt(
     Ok(0)
 }
 
+pub fn sys_getsockopt(
+    fd: usize,
+    level: usize,
+    optname: usize,
+    optval: *mut u8,
+    optlen: *mut u32,
+) -> SysResult {
+    info!(
+        "getsockopt: fd: {}, level: {}, optname: {} optval: {:?} optlen: {:?}",
+        fd, level, optname, optval, optlen
+    );
+    warn!("sys_getsockopt is unimplemented");
+    Err(SysError::ENOPROTOOPT)
+}
+
 #[repr(C)]
 struct SockaddrIn {
     sin_family: u16,
@@ -700,3 +715,11 @@ pub fn poll_socket(wrapper: &SocketWrapper) -> (bool, bool, bool) {
 
     (input, output, err)
 }
+
+pub fn sys_dup2_socket(proc: &mut Process, wrapper: SocketWrapper, fd: usize) -> SysResult {
+    proc.files.insert(
+        fd,
+        FileLike::Socket(wrapper),
+    );
+    Ok(fd as isize)
+}

kernel/src/syscall/proc.rs

@@ -48,23 +48,28 @@ pub fn sys_wait(pid: usize, code: *mut i32) -> SysResult {
     }
 }
 
-pub fn sys_exec(name: *const u8, argc: usize, argv: *const *const u8, tf: &mut TrapFrame) -> SysResult {
+pub fn sys_exec(name: *const u8, argv: *const *const u8, envp: *const *const u8, tf: &mut TrapFrame) -> SysResult {
+    info!("exec: name: {:?}, argv: {:?} envp: {:?}", name, argv, envp);
     let proc = process();
     let name = if name.is_null() { String::from("") } else {
         unsafe { proc.memory_set.check_and_clone_cstr(name)? }
     };
-    if argc <= 0 {
+
+    if argv.is_null() {
         return Err(SysError::EINVAL);
     }
     // Check and copy args to kernel
     let mut args = Vec::new();
     unsafe {
-        for &ptr in slice::from_raw_parts(argv, argc) {
-            let arg = proc.memory_set.check_and_clone_cstr(ptr)?;
+        let mut current_argv = argv as *const *const u8;
+        while !(*current_argv).is_null() {
+            let arg = proc.memory_set.check_and_clone_cstr(*current_argv)?;
             args.push(arg);
+            current_argv = current_argv.add(1);
         }
     }
-    info!("exec: name: {:?}, args: {:?}", name, args);
+    info!("exec: args {:?}", args);
+    info!("exec {:?}", proc.files);
 
     // Read program file
     let path = args[0].as_str();
@@ -77,6 +82,8 @@ pub fn sys_exec(name: *const u8, argc: usize, argv: *const *const u8, tf: &mut T
     // Make new Thread
     let iter = args.iter().map(|s| s.as_str());
     let mut thread = Thread::new_user(buf.as_slice(), iter);
+    thread.proc.lock().files = proc.files.clone();
+    thread.proc.lock().cwd = proc.cwd.clone();
 
     // Activate new page table
     unsafe { thread.proc.lock().memory_set.activate(); }