T0b1/wasmtime
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge branch 'pch/wiggle_trapping' into pch/wasi_common_cap_std

Browse Source
This commit is contained in:
Pat Hickey
2021-01-07 14:10:59 -08:00
parent c2004001cb b149a03d5d
commit 13cd7a4a8e
25 changed files with 183 additions and 142 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
Cargo.lock generated
View File

@@ -3073,7 +3073,7 @@ dependencies = [
[[package]]
name = "witx"
version = "0.8.7"
version = "0.8.8"
dependencies = [
"anyhow",
"diff",

2
crates/wasi-common/WASI

Submodule crates/wasi-common/WASI updated: 71f0425147...8deb71ddd0

4
crates/wasi-common/src/error.rs
View File

@@ -17,6 +17,10 @@ pub enum Error {
#[error("GetRandom: {0}")]
GetRandom(#[from] getrandom::Error),
/// Some corners of the WASI standard are unsupported.
#[error("Unsupported: {0}")]
Unsupported(&'static str),
/// The host OS may return an io error that doesn't match one of the
/// wasi errno variants we expect. We do not expose the details of this
/// error to the user.

23
crates/wasi-common/src/snapshots/wasi_snapshot_preview1.rs
View File

@@ -714,14 +714,17 @@ impl<'a> WasiSnapshotPreview1 for WasiCtx {
Ok(nevents)
}
fn proc_exit(&self, _rval: types::Exitcode) -> std::result::Result<(), ()> {
// proc_exit is special in that it's expected to unwind the stack, which
// typically requires runtime-specific logic.
unimplemented!("runtimes are expected to override this implementation")
fn proc_exit(&self, status: types::Exitcode) -> wiggle::Trap {
// Check that the status is within WASI's range.
if status < 126 {
wiggle::Trap::I32Exit(status as i32)
} else {
wiggle::Trap::String("exit with invalid exit status outside of [0..126)".to_owned())
}
}
fn proc_raise(&self, _sig: types::Signal) -> Result<()> {
unimplemented!("proc_raise")
Err(Error::Unsupported("proc_raise"))
}
fn sched_yield(&self) -> Result<()> {
@@ -741,7 +744,7 @@ impl<'a> WasiSnapshotPreview1 for WasiCtx {
_ri_data: &types::IovecArray<'_>,
_ri_flags: types::Riflags,
) -> Result<(types::Size, types::Roflags)> {
unimplemented!("sock_recv")
Err(Error::Unsupported("sock_recv"))
}
fn sock_send(
@@ -750,11 +753,11 @@ impl<'a> WasiSnapshotPreview1 for WasiCtx {
_si_data: &types::CiovecArray<'_>,
_si_flags: types::Siflags,
) -> Result<types::Size> {
unimplemented!("sock_send")
Err(Error::Unsupported("sock_send"))
}
fn sock_shutdown(&self, _fd: types::Fd, _how: types::Sdflags) -> Result<()> {
unimplemented!("sock_shutdown")
Err(Error::Unsupported("sock_shutdown"))
}
}
@@ -801,7 +804,7 @@ impl WasiCtx {
Err(error) => {
events.push(types::Event {
userdata: subscription.userdata,
error: error.into(),
error: error.try_into().expect("non-trapping error"),
type_: types::Eventtype::FdRead,
fd_readwrite: types::EventFdReadwrite {
nbytes: 0,
@@ -827,7 +830,7 @@ impl WasiCtx {
Err(error) => {
events.push(types::Event {
userdata: subscription.userdata,
error: error.into(),
error: error.try_into().expect("non-trapping error"),
type_: types::Eventtype::FdWrite,
fd_readwrite: types::EventFdReadwrite {
nbytes: 0,

13
crates/wasi-common/src/snapshots/wasi_unstable.rs
View File

@@ -23,15 +23,16 @@ impl types::GuestErrorConversion for WasiCtx {
}
impl types::UserErrorConversion for WasiCtx {
fn errno_from_error(&self, e: Error) -> Result<Errno, String> {
fn errno_from_error(&self, e: Error) -> Result<Errno, wiggle::Trap> {
tracing::debug!("Error: {:?}", e);
Ok(e.into())
e.try_into()
}
}
impl From<Error> for Errno {
fn from(e: Error) -> Errno {
types_new::Errno::from(e).into()
impl TryFrom<Error> for Errno {
type Error = wiggle::Trap;
fn try_from(e: Error) -> Result<Errno, wiggle::Trap> {
Ok(types_new::Errno::try_from(e)?.into())
}
}
@@ -346,7 +347,7 @@ impl wasi_unstable::WasiUnstable for WasiCtx {
Ok(nevents)
}
fn proc_exit(&self, rval: Exitcode) -> Result<(), ()> {
fn proc_exit(&self, rval: Exitcode) -> wiggle::Trap {
WasiSnapshotPreview1::proc_exit(self, rval)
}

4
crates/wasi-common/src/sys/unix/poll.rs
View File

@@ -117,7 +117,7 @@ fn handle_fd_event(
let output_event = if revents.contains(PollFlags::POLLNVAL) {
Event {
userdata: fd_event.userdata,
error: Error::Badf.into(),
error: Error::Badf.try_into().unwrap(),
type_: fd_event.r#type,
fd_readwrite: EventFdReadwrite {
nbytes: 0,
@@ -127,7 +127,7 @@ fn handle_fd_event(
} else if revents.contains(PollFlags::POLLERR) {
Event {
userdata: fd_event.userdata,
error: Error::Io.into(),
error: Error::Io.try_into().unwrap(),
type_: fd_event.r#type,
fd_readwrite: EventFdReadwrite {
nbytes: 0,

81
crates/wasi-common/src/wasi.rs
View File

@@ -1,4 +1,5 @@
use crate::{Error, WasiCtx};
use std::convert::{TryFrom, TryInto};
use tracing::debug;
wiggle::from_witx!({
@@ -23,47 +24,51 @@ impl types::GuestErrorConversion for WasiCtx {
}
impl types::UserErrorConversion for WasiCtx {
fn errno_from_error(&self, e: Error) -> Result<Errno, String> {
fn errno_from_error(&self, e: Error) -> Result<Errno, wiggle::Trap> {
debug!("Error: {:?}", e);
Ok(e.into())
e.try_into()
}
}
impl From<Error> for Errno {
fn from(e: Error) -> Errno {
impl TryFrom<Error> for Errno {
type Error = wiggle::Trap;
fn try_from(e: Error) -> Result<Errno, wiggle::Trap> {
match e {
Error::Guest(e) => e.into(),
Error::TryFromInt(_) => Errno::Overflow,
Error::Utf8(_) => Errno::Ilseq,
Error::UnexpectedIo(_) => Errno::Io,
Error::GetRandom(_) => Errno::Io,
Error::TooBig => Errno::TooBig,
Error::Acces => Errno::Acces,
Error::Badf => Errno::Badf,
Error::Busy => Errno::Busy,
Error::Exist => Errno::Exist,
Error::Fault => Errno::Fault,
Error::Fbig => Errno::Fbig,
Error::Ilseq => Errno::Ilseq,
Error::Inval => Errno::Inval,
Error::Io => Errno::Io,
Error::Isdir => Errno::Isdir,
Error::Loop => Errno::Loop,
Error::Mfile => Errno::Mfile,
Error::Mlink => Errno::Mlink,
Error::Nametoolong => Errno::Nametoolong,
Error::Nfile => Errno::Nfile,
Error::Noent => Errno::Noent,
Error::Nomem => Errno::Nomem,
Error::Nospc => Errno::Nospc,
Error::Notdir => Errno::Notdir,
Error::Notempty => Errno::Notempty,
Error::Notsup => Errno::Notsup,
Error::Overflow => Errno::Overflow,
Error::Pipe => Errno::Pipe,
Error::Perm => Errno::Perm,
Error::Spipe => Errno::Spipe,
Error::Notcapable => Errno::Notcapable,
Error::Guest(e) => Ok(e.into()),
Error::TryFromInt(_) => Ok(Errno::Overflow),
Error::Utf8(_) => Ok(Errno::Ilseq),
Error::UnexpectedIo(_) => Ok(Errno::Io),
Error::GetRandom(_) => Ok(Errno::Io),
Error::TooBig => Ok(Errno::TooBig),
Error::Acces => Ok(Errno::Acces),
Error::Badf => Ok(Errno::Badf),
Error::Busy => Ok(Errno::Busy),
Error::Exist => Ok(Errno::Exist),
Error::Fault => Ok(Errno::Fault),
Error::Fbig => Ok(Errno::Fbig),
Error::Ilseq => Ok(Errno::Ilseq),
Error::Inval => Ok(Errno::Inval),
Error::Io => Ok(Errno::Io),
Error::Isdir => Ok(Errno::Isdir),
Error::Loop => Ok(Errno::Loop),
Error::Mfile => Ok(Errno::Mfile),
Error::Mlink => Ok(Errno::Mlink),
Error::Nametoolong => Ok(Errno::Nametoolong),
Error::Nfile => Ok(Errno::Nfile),
Error::Noent => Ok(Errno::Noent),
Error::Nomem => Ok(Errno::Nomem),
Error::Nospc => Ok(Errno::Nospc),
Error::Notdir => Ok(Errno::Notdir),
Error::Notempty => Ok(Errno::Notempty),
Error::Notsup => Ok(Errno::Notsup),
Error::Overflow => Ok(Errno::Overflow),
Error::Pipe => Ok(Errno::Pipe),
Error::Perm => Ok(Errno::Perm),
Error::Spipe => Ok(Errno::Spipe),
Error::Notcapable => Ok(Errno::Notcapable),
Error::Unsupported(feature) => {
Err(wiggle::Trap::String(format!("unsupported: {}", feature)))
}
}
}
}
@@ -80,8 +85,8 @@ impl From<wiggle::GuestError> for Errno {
PtrBorrowed { .. } => Self::Fault,
InvalidUtf8 { .. } => Self::Ilseq,
TryFromIntError { .. } => Self::Overflow,
InFunc { .. } => Self::Inval,
InDataField { .. } => Self::Inval,
InFunc { err, .. } => Errno::from(*err),
InDataField { err, .. } => Errno::from(*err),
SliceLengthsDiffer { .. } => Self::Fault,
BorrowCheckerOutOfHandles { .. } => Self::Fault,
}

2
crates/wasi-nn/src/witx.rs
View File

@@ -22,7 +22,7 @@ impl types::GuestErrorConversion for WasiNnCtx {
}
impl<'a> types::UserErrorConversion for WasiNnCtx {
fn errno_from_wasi_nn_error(&self, e: WasiNnError) -> Result<Errno, String> {
fn errno_from_wasi_nn_error(&self, e: WasiNnError) -> Result<Errno, wiggle::Trap> {
eprintln!("Host error: {:?}", e);
match e {
WasiNnError::OpenvinoError(_) => unimplemented!(),

21
crates/wasi/src/lib.rs
View File

@@ -1,5 +1,3 @@
use wasmtime::Trap;
pub mod old;
pub use wasi_common::virtfs;
@@ -26,13 +24,8 @@ modules. This structure exports all that various fields of the wasi instance
as fields which can be used to implement your own instantiation logic, if
necessary. Additionally [`Wasi::get_export`] can be used to do name-based
resolution.",
// Don't use the wiggle generated code to implement proc_exit, we need
// to hook directly into the runtime there:
function_override: {
proc_exit => wasi_proc_exit
}
},
},
});
pub fn is_wasi_module(name: &str) -> bool {
@@ -41,17 +34,3 @@ pub fn is_wasi_module(name: &str) -> bool {
// trick.
name.starts_with("wasi")
}
/// Implement the WASI `proc_exit` function. This function is implemented here
/// instead of in wasi-common so that we can use the runtime to perform an
/// unwind rather than exiting the host process.
fn wasi_proc_exit(status: i32) -> Result<(), Trap> {
// Check that the status is within WASI's range.
if status >= 0 && status < 126 {
Err(Trap::i32_exit(status))
} else {
Err(Trap::new(
"exit with invalid exit status outside of [0..126)",
))
}
}

7
crates/wasi/src/old/snapshot_0.rs
View File

@@ -1,8 +1,6 @@
pub use wasi_common::virtfs;
pub use wasi_common::{WasiCtx, WasiCtxBuilder};
use crate::wasi_proc_exit;
// Defines a `struct Wasi` with member fields and appropriate APIs for dealing
// with all the various WASI exports.
wasmtime_wiggle::wasmtime_integration!({
@@ -25,13 +23,8 @@ modules. This structure exports all that various fields of the wasi instance
as fields which can be used to implement your own instantiation logic, if
necessary. Additionally [`Wasi::get_export`] can be used to do name-based
resolution.",
// Don't use the wiggle generated code to implement proc_exit, we need
// to hook directly into the runtime there:
function_override: {
proc_exit => wasi_proc_exit
}
},
},
});
pub fn is_wasi_module(name: &str) -> bool {

11
crates/wiggle/README.md
View File

@@ -5,3 +5,14 @@ invoked as a Rust procedural macro.
Wiggle is not specialized to any particular WebAssembly runtime. It is usable
in at least Wasmtime and Lucet.
## Learning more
Read the docs on [docs.rs](https://docs.rs/wiggle/).
There are child crates for [integrating with Wasmtime](https://github.com/bytecodealliance/wasmtime/tree/main/crates/wiggle/wasmtime) and [Lucet](https://github.com/bytecodealliance/lucet/tree/main/lucet-wiggle).
The [wasi-common crate](https://github.com/bytecodealliance/wasmtime/tree/main/crates/wasi-common) is implemented using Wiggle and the [wasmtime-wasi
crate](https://github.com/bytecodealliance/wasmtime/tree/main/crates/wasi) integrates wasi-common with the Wasmtime engine.
Andrew Brown wrote a great [blog post](https://bytecodealliance.org/articles/implementing-wasi-nn-in-wasmtime) on using Wiggle with Wasmtime.

25
crates/wiggle/generate/src/funcs.rs
View File

@@ -36,12 +36,6 @@ pub fn define_func(
witx::CoreParamSignifies::Value(atom) => names.atom_type(atom),
_ => unreachable!("ret should always be passed by value"),
}
} else if func.noreturn {
// Ideally we would return `quote!(!)` here, but, we'd have to change
// the error handling logic in all the marshalling code to never return,
// and instead provide some other way to bail to the context...
// noreturn func
unimplemented!("noreturn funcs not supported yet!")
} else {
quote!(())
};
@@ -174,7 +168,23 @@ pub fn define_func(
let mod_name = &module.name.as_str();
let func_name = &func.name.as_str();
quote!(pub fn #ident(#abi_args) -> Result<#abi_ret, String> {
if func.noreturn {
quote!(pub fn #ident(#abi_args) -> Result<#abi_ret, wiggle::Trap> {
let _span = #rt::tracing::span!(
#rt::tracing::Level::TRACE,
"wiggle abi",
module = #mod_name,
function = #func_name
);
let _enter = _span.enter();
#(#marshal_args)*
#log_marshalled_args
let trap = #trait_name::#ident(ctx, #(#trait_args),*);
Err(trap)
})
} else {
quote!(pub fn #ident(#abi_args) -> Result<#abi_ret, wiggle::Trap> {
let _span = #rt::tracing::span!(
#rt::tracing::Level::TRACE,
"wiggle abi",
@@ -194,6 +204,7 @@ pub fn define_func(
#success
})
}
}
fn marshal_arg(
names: &Names,

2
crates/wiggle/generate/src/lib.rs
View File

@@ -40,7 +40,7 @@ pub fn generate(doc: &witx::Document, names: &Names, errs: &ErrorTransform) -> T
let abi_typename = names.type_ref(&errtype.abi_type(), anon_lifetime());
let user_typename = errtype.typename();
let methodname = names.user_error_conversion_method(&errtype);
quote!(fn #methodname(&self, e: super::#user_typename) -> Result<#abi_typename, String>;)
quote!(fn #methodname(&self, e: super::#user_typename) -> Result<#abi_typename, wiggle::Trap>;)
});
let user_error_conversion = quote! {
pub trait UserErrorConversion {

10
crates/wiggle/generate/src/module_trait.rs
View File

@@ -48,6 +48,8 @@ pub fn define_module_trait(names: &Names, m: &Module, errxform: &ErrorTransform)
};
quote!(#arg_name: #arg_type)
});
let result = if !f.noreturn {
let rets = f
.results
.iter()
@@ -65,11 +67,15 @@ pub fn define_module_trait(names: &Names, m: &Module, errxform: &ErrorTransform)
}
})
.unwrap_or(quote!(()));
quote!( Result<(#(#rets),*), #err> )
} else {
quote!(wiggle::Trap)
};
if is_anonymous {
quote!(fn #funcname(&self, #(#args),*) -> Result<(#(#rets),*), #err>;)
quote!(fn #funcname(&self, #(#args),*) -> #result; )
} else {
quote!(fn #funcname<#lifetime>(&self, #(#args),*) -> Result<(#(#rets),*), #err>;)
quote!(fn #funcname<#lifetime>(&self, #(#args),*) -> #result;)
}
});
quote! {

13
crates/wiggle/src/lib.rs
View File

@@ -928,3 +928,16 @@ impl Pointee for str {
<[u8]>::debug(pointer, f)
}
}
/// A runtime-independent way for Wiggle to terminate WebAssembly execution.
/// Functions that are marked `(@witx noreturn)` will always return a Trap.
/// Other functions that want to Trap can do so via their `UserErrorConversion`
/// trait, which transforms the user's own error type into a `Result<abierror, Trap>`.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Trap {
/// A Trap which indicates an i32 (posix-style) exit code. Runtimes may have a
/// special way of dealing with this for WASI embeddings and otherwise.
I32Exit(i32),
/// Any other Trap is just an unstructured String, for reporting and debugging.
String(String),
}

2
crates/wiggle/test-helpers/examples/tracing.rs
View File

@@ -36,7 +36,7 @@ impl_errno!(types::Errno, types::GuestErrorConversion);
/// When the `errors` mapping in witx is non-empty, we need to impl the
/// types::UserErrorConversion trait that wiggle generates from that mapping.
impl<'a> types::UserErrorConversion for WasiCtx<'a> {
fn errno_from_rich_error(&self, e: RichError) -> Result<types::Errno, String> {
fn errno_from_rich_error(&self, e: RichError) -> Result<types::Errno, wiggle::Trap> {
wiggle::tracing::debug!(
rich_error = wiggle::tracing::field::debug(&e),
"error conversion"

19
crates/wiggle/tests/errors.rs
View File

@@ -34,7 +34,7 @@ mod convert_just_errno {
/// When the `errors` mapping in witx is non-empty, we need to impl the
/// types::UserErrorConversion trait that wiggle generates from that mapping.
impl<'a> types::UserErrorConversion for WasiCtx<'a> {
fn errno_from_rich_error(&self, e: RichError) -> Result<types::Errno, String> {
fn errno_from_rich_error(&self, e: RichError) -> Result<types::Errno, wiggle::Trap> {
// WasiCtx can collect a Vec<String> log so we can test this. We're
// logging the Display impl that `thiserror::Error` provides us.
self.log.borrow_mut().push(e.to_string());
@@ -115,8 +115,9 @@ mod convert_multiple_error_types {
TooMuchCoffee(usize),
}
// Just like the other error, except that we have a second errno type:
// trivial function.
// Just like the prior test, except that we have a second errno type. This should mean there
// are two functions in UserErrorConversion.
// Additionally, test that the function "baz" marked noreturn always returns a wiggle::Trap.
wiggle::from_witx!({
witx_literal: "
(typename $errno (enum u8 $ok $invalid_arg $picket_line))
@@ -127,7 +128,10 @@ mod convert_multiple_error_types {
(result $err $errno))
(@interface func (export \"bar\")
(param $drink u32)
(result $err $errno2)))
(result $err $errno2))
(@interface func (export \"baz\")
(param $drink u32)
(@witx noreturn)))
",
ctx: WasiCtx,
errors: { errno => RichError, errno2 => AnotherRichError },
@@ -159,13 +163,13 @@ mod convert_multiple_error_types {
// each member of the `errors` mapping.
// Bodies elided.
impl<'a> types::UserErrorConversion for WasiCtx<'a> {
fn errno_from_rich_error(&self, _e: RichError) -> Result<types::Errno, String> {
fn errno_from_rich_error(&self, _e: RichError) -> Result<types::Errno, wiggle::Trap> {
unimplemented!()
}
fn errno2_from_another_rich_error(
&self,
_e: AnotherRichError,
) -> Result<types::Errno2, String> {
) -> Result<types::Errno2, wiggle::Trap> {
unimplemented!()
}
}
@@ -178,5 +182,8 @@ mod convert_multiple_error_types {
fn bar(&self, _: u32) -> Result<(), AnotherRichError> {
unimplemented!()
}
fn baz(&self, _: u32) -> wiggle::Trap {
unimplemented!()
}
}
}

5
crates/wiggle/wasmtime/macro/src/lib.rs
View File

@@ -199,8 +199,9 @@ fn generate_func(
#(#arg_names),*
);
match result {
Ok(r) => {return Ok(r.into());},
Err(err) => { return Err(wasmtime::Trap::new(err)); },
Ok(r) => Ok(r.into()),
Err(wasmtime_wiggle::Trap::String(err)) => Err(wasmtime::Trap::new(err)),
Err(wasmtime_wiggle::Trap::I32Exit(err)) => Err(wasmtime::Trap::i32_exit(err)),
}
}
}

1
tests/wasm/exit125_wasi_snapshot0.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_unstable" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 125))
)

1
tests/wasm/exit125_wasi_snapshot1.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_snapshot_preview1" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 125))
)

1
tests/wasm/exit126_wasi_snapshot0.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_unstable" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 126))
)

1
tests/wasm/exit126_wasi_snapshot1.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_snapshot_preview1" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 126))
)

1
tests/wasm/exit2_wasi_snapshot0.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_unstable" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 2))
)

1
tests/wasm/exit2_wasi_snapshot1.wat
View File

@@ -1,6 +1,7 @@
(module
(import "wasi_snapshot_preview1" "proc_exit"
(func $__wasi_proc_exit (param i32)))
(memory (export "memory") 0)
(func $_start
(call $__wasi_proc_exit (i32.const 2))
)

1
tests/wasm/exit_with_saved_fprs.wat
View File

@@ -3,6 +3,7 @@
(type (func (param i32)))
(import "wasi_snapshot_preview1" "proc_exit" (func (type 0)))
(memory (export "memory") 0)
(func $exit (param i32)
local.get 0