Struct Req 

pub(crate) struct Req<'a> {
    pub ctx: &'a Ctx,
    pub listener: i32,
    pub id: u64,
    pub pid: u32,
    pub args: [u64; 6],
    pub raw_nr: i32,
    pub abi: Abi,
    pub variant: Variant,
    view: OnceCell<Arc<View>>,
}

One notification plus the shared state needed to serve it.

Fields

ctx: &'a Ctx

listener: i32

id: u64

pid: u32

args: [u64; 6]

raw_nr: i32

Syscall number as the tracee issued it, in its own ABI.

abi: Abi

ABI the request came through; 32-bit pointers are already zero-extended.

variant: Variant

How an i386 request differs from the x86_64 number it was mapped to.

view: OnceCell<Arc<View>>

The caller’s view, looked up once per request.

Implementations

impl<'a> Req<'a>

pub fn arg(&self, i: usize) -> u64

pub fn view(&self) -> &View

The view the calling process lives in.

pub fn fs(&self) -> &Fs

The calling process’s filesystem view.

fn arg_i64(&self, i: usize) -> i64

fn dirfd(&self, i: usize) -> i32

pub fn tgid(&self) -> i32

Thread-group id of the calling thread.

pub fn path(&self, i: usize) -> Result<Vec<u8>, i32>

Reads the NUL-terminated path in argument i, rewriting /proc/self and /proc/thread-self to the tracee’s own entries since the supervisor would otherwise see its own.

pub fn translate( &self, dirfd: i32, path: &[u8], deref_final: bool, ) -> Result<Resolved, i32>

Translates path relative to dirfd into the object to act on.

pub fn translate_or_dirfd( &self, dirfd: i32, path: &[u8], deref_final: bool, ) -> Result<Resolved, i32>

Translates like Req::translate, except that an empty path names dirfd itself.

AT_EMPTY_PATH asks for that, and readlinkat always takes it; for AT_FDCWD it is the tracee’s working directory.

Arguments

• dirfd - Base descriptor for a relative path, or libc::AT_FDCWD.
• path - Path bytes as read from the tracee, without NUL.
• deref_final - Follow a symlink in the final component.

Errors

As Req::translate, or the errno of reading the descriptor’s path.

pub fn valid(&self) -> Result<(), i32>

Re-validates the notification; Err(DROPPED) when the tracee is gone.

pub fn check_writable(&self, resolved: &Resolved) -> Result<(), i32>

Refuses with EROFS when the resolved path lies under a read-only binding.

pub fn write(&self, addr: u64, data: &[u8]) -> Result<(), i32>

pub fn read(&self, addr: u64, len: usize) -> Result<Vec<u8>, i32>