Add shebang support

api/src/imp/fs/io.rs

@@ -23,6 +23,37 @@ pub fn sys_read(fd: i32, buf: UserPtr<u8>, len: usize) -> LinuxResult<isize> {
     Ok(get_file_like(fd)?.read(buf)? as _)
 }
 
+pub fn sys_readv(fd: i32, iov: UserPtr<iovec>, iocnt: usize) -> LinuxResult<isize> {
+    if !(0..=1024).contains(&iocnt) {
+        return Err(LinuxError::EINVAL);
+    }
+
+    let iovs = iov.get_as_mut_slice(iocnt)?;
+    let mut ret = 0;
+    for iov in iovs {
+        if iov.iov_len == 0 {
+            continue;
+        }
+        let buf = UserPtr::<u8>::from(iov.iov_base as usize);
+        let buf = buf.get_as_mut_slice(iov.iov_len as _)?;
+        debug!(
+            "sys_readv <= fd: {}, buf: {:p}, len: {}",
+            fd,
+            buf.as_ptr(),
+            buf.len()
+        );
+
+        let read = get_file_like(fd)?.read(buf)?;
+        ret += read as isize;
+
+        if read < buf.len() {
+            break;
+        }
+    }
+
+    Ok(ret)
+}
+
 /// Write data to the file indicated by `fd`.
 ///
 /// Return the written size if success.

core/src/mm.rs

@@ -2,7 +2,7 @@
 
 use core::ffi::CStr;
 
-use alloc::{string::String, vec};
+use alloc::{borrow::ToOwned, string::String, vec, vec::Vec};
 use axerrno::{AxError, AxResult};
 use axhal::{mem::virt_to_phys, paging::MappingFlags};
 use axmm::{AddrSpace, kernel_aspace};
@@ -111,6 +111,18 @@ pub fn load_user_app(
         return Err(AxError::InvalidInput);
     }
     let file_data = axfs::api::read(args[0].as_str())?;
+    if file_data.starts_with(b"#!") {
+        let head = &file_data[2..file_data.len().min(256)];
+        let pos = head.iter().position(|c| *c == b'\n').unwrap_or(head.len());
+        let line = core::str::from_utf8(&head[..pos]).map_err(|_| AxError::InvalidData)?;
+
+        let new_args: Vec<String> = line
+            .splitn(2, |c: char| c.is_ascii_whitespace())
+            .map(|s| s.trim_ascii().to_owned())
+            .chain(args.iter().cloned())
+            .collect();
+        return load_user_app(uspace, &new_args, envs);
+    }
     let elf = ElfFile::new(&file_data).map_err(|_| AxError::InvalidData)?;
 
     if let Some(interp) = elf

src/syscall.rs

@@ -50,6 +50,7 @@ fn handle_syscall(tf: &mut TrapFrame, syscall_num: usize) -> isize {
 
         // io
         Sysno::read => sys_read(tf.arg0() as _, tf.arg1().into(), tf.arg2() as _),
+        Sysno::readv => sys_readv(tf.arg0() as _, tf.arg1().into(), tf.arg2() as _),
         Sysno::write => sys_write(tf.arg0() as _, tf.arg1().into(), tf.arg2() as _),
         Sysno::writev => sys_writev(tf.arg0() as _, tf.arg1().into(), tf.arg2() as _),
         Sysno::lseek => sys_lseek(tf.arg0() as _, tf.arg1() as _, tf.arg2() as _),