Merge updates from ch7

os/src/syscall/fs.rs

@@ -6,6 +6,7 @@ use crate::mm::{
 };
 use crate::task::{current_user_token, current_task};
 use crate::fs::{make_pipe, OpenFlags, open_file};
+use alloc::sync::Arc;
 
 pub fn sys_write(fd: usize, buf: *const u8, len: usize) -> isize {
     let token = current_user_token();
@@ -93,4 +94,18 @@ pub fn sys_pipe(pipe: *mut usize) -> isize {
     *translated_refmut(token, pipe) = read_fd;
     *translated_refmut(token, unsafe { pipe.add(1) }) = write_fd;
     0
+}
+
+pub fn sys_dup(fd: usize) -> isize {
+    let task = current_task().unwrap();
+    let mut inner = task.acquire_inner_lock();
+    if fd >= inner.fd_table.len() {
+        return -1;
+    }
+    if inner.fd_table[fd].is_none() {
+        return -1;
+    }
+    let new_fd = inner.alloc_fd();
+    inner.fd_table[new_fd] = Some(Arc::clone(inner.fd_table[fd].as_ref().unwrap()));
+    new_fd as isize
 }

os/src/syscall/mod.rs

@@ -1,3 +1,4 @@
+const SYSCALL_DUP: usize = 24;
 const SYSCALL_OPEN: usize = 56;
 const SYSCALL_CLOSE: usize = 57;
 const SYSCALL_PIPE: usize = 59;
@@ -19,6 +20,7 @@ use process::*;
 
 pub fn syscall(syscall_id: usize, args: [usize; 3]) -> isize {
     match syscall_id {
+        SYSCALL_DUP=> sys_dup(args[0]),
         SYSCALL_OPEN => sys_open(args[0] as *const u8, args[1] as u32),
         SYSCALL_CLOSE => sys_close(args[0]),
         SYSCALL_PIPE => sys_pipe(args[0] as *mut usize),
@@ -29,7 +31,7 @@ pub fn syscall(syscall_id: usize, args: [usize; 3]) -> isize {
         SYSCALL_GET_TIME => sys_get_time(),
         SYSCALL_GETPID => sys_getpid(),
         SYSCALL_FORK => sys_fork(),
-        SYSCALL_EXEC => sys_exec(args[0] as *const u8),
+        SYSCALL_EXEC => sys_exec(args[0] as *const u8, args[1] as *const usize),
         SYSCALL_WAITPID => sys_waitpid(args[0] as isize, args[1] as *mut i32),
         _ => panic!("Unsupported syscall_id: {}", syscall_id),
     }

os/src/syscall/process.rs

@@ -9,12 +9,15 @@ use crate::timer::get_time_ms;
 use crate::mm::{
     translated_str,
     translated_refmut,
+    translated_ref,
 };
 use crate::fs::{
     open_file,
     OpenFlags,
 };
 use alloc::sync::Arc;
+use alloc::vec::Vec;
+use alloc::string::String;
 
 pub fn sys_exit(exit_code: i32) -> ! {
     exit_current_and_run_next(exit_code);
@@ -48,14 +51,25 @@ pub fn sys_fork() -> isize {
     new_pid as isize
 }
 
-pub fn sys_exec(path: *const u8) -> isize {
+pub fn sys_exec(path: *const u8, mut args: *const usize) -> isize {
     let token = current_user_token();
     let path = translated_str(token, path);
+    let mut args_vec: Vec<String> = Vec::new();
+    loop {
+        let arg_str_ptr = *translated_ref(token, args);
+        if arg_str_ptr == 0 {
+            break;
+        }
+        args_vec.push(translated_str(token, arg_str_ptr as *const u8));
+        unsafe { args = args.add(1); }
+    }
     if let Some(app_inode) = open_file(path.as_str(), OpenFlags::RDONLY) {
         let all_data = app_inode.read_all();
         let task = current_task().unwrap();
-        task.exec(all_data.as_slice());
-        0
+        let argc = args_vec.len();
+        task.exec(all_data.as_slice(), args_vec);
+        // return argc because cx.x[10] will be covered with it later
+        argc as isize
     } else {
         -1
     }