4 impl<'mir, 'tcx> EvalContextExt<'mir, 'tcx> for crate::MiriEvalContext<'mir, 'tcx> {}
5 pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx> {
6 fn emulate_foreign_item_by_name(
9 args: &[OpTy<'tcx, Tag>],
10 dest: PlaceTy<'tcx, Tag>,
11 _ret: mir::BasicBlock,
12 ) -> InterpResult<'tcx, bool> {
13 let this = self.eval_context_mut();
16 "__errno_location" => {
17 let errno_place = this.machine.last_error.unwrap();
18 this.write_scalar(errno_place.to_ref().to_scalar()?, dest)?;
21 // File related shims (but also see "syscall" below for statx)
23 // The only reason this is not in the `posix` module is because the `macos` item has a
26 let result = this.close(args[0])?;
27 this.write_scalar(Scalar::from_int(result, dest.layout.size), dest)?;
32 // This is a POSIX function but it has only been tested on linux.
34 let result = this.clock_gettime(args[0], args[1])?;
35 this.write_scalar(Scalar::from_int(result, dest.layout.size), dest)?;
39 "pthread_getattr_np" => {
40 this.write_null(dest)?;
44 let sys_getrandom = this
45 .eval_path_scalar(&["libc", "SYS_getrandom"])?
46 .expect("Failed to get libc::SYS_getrandom")
47 .to_machine_usize(this)?;
50 .eval_path_scalar(&["libc", "SYS_statx"])?
51 .expect("Failed to get libc::SYS_statx")
52 .to_machine_usize(this)?;
54 match this.read_scalar(args[0])?.to_machine_usize(this)? {
55 // `libc::syscall(NR_GETRANDOM, buf.as_mut_ptr(), buf.len(), GRND_NONBLOCK)`
56 // is called if a `HashMap` is created the regular way (e.g. HashMap<K, V>).
57 id if id == sys_getrandom => {
58 // The first argument is the syscall id,
60 getrandom(this, &args[1..], dest)?;
62 // `statx` is used by `libstd` to retrieve metadata information on `linux`
63 // instead of using `stat`,`lstat` or `fstat` as on `macos`.
64 id if id == sys_statx => {
65 // The first argument is the syscall id,
67 let result = this.linux_statx(args[1], args[2], args[3], args[4], args[5])?;
68 this.write_scalar(Scalar::from_int(result, dest.layout.size), dest)?;
70 id => throw_unsup_format!("miri does not support syscall ID {}", id),
75 getrandom(this, args, dest)?;
78 "sched_getaffinity" => {
79 // Return an error; `num_cpus` then falls back to `sysconf`.
80 this.write_scalar(Scalar::from_int(-1, dest.layout.size), dest)?;
83 _ => throw_unsup_format!("can't call foreign function: {}", link_name),
90 // Shims the linux `getrandom` syscall.
92 this: &mut MiriEvalContext<'_, 'tcx>,
93 args: &[OpTy<'tcx, Tag>],
94 dest: PlaceTy<'tcx, Tag>,
95 ) -> InterpResult<'tcx> {
96 let ptr = this.read_scalar(args[0])?.not_undef()?;
97 let len = this.read_scalar(args[1])?.to_machine_usize(this)?;
99 // The only supported flags are GRND_RANDOM and GRND_NONBLOCK,
100 // neither of which have any effect on our current PRNG.
101 let _flags = this.read_scalar(args[2])?.to_i32()?;
103 this.gen_random(ptr, len as usize)?;
104 this.write_scalar(Scalar::from_uint(len, dest.layout.size), dest)?;