Commit Graph

47 Commits

Author SHA1 Message Date
Jakub Konka
7a4c881409 Fix read/write for GuestTypeCopy members of non-copy structs
This commit fixes stubs for struct members that are `GuestTypeCopy`
but are not `GuestTypeClone`. In this case, we cannot rely on methods
`T::read_from_guest` or `T::write_to_guest` since these are only
available if `T: GuestTypeClone`. In those cases, we can and should
dereference the location pointer to `T` and copy the result in/out
respectively.
2020-02-26 18:23:46 +01:00
Jakub Konka
678065011e Implement fmt::Display for enums, flags, and ints (#18)
* Implement fmt::Display for enums

`wasi_common` relies on `strerror` to nicely format error messages.
`strerror` is autoimplemented in `wig`. I thought it might be useful
to provide a Rust-idiomatic alternative which boils down to autoimplementing
`fmt::Display` for all enums.

* Implement fmt::Display for flags

* Implement fmt::Display for ints
2020-02-24 21:11:08 +01:00
Pat Hickey
f77000ad8f move ctx into wiggle-tests crate 2020-02-21 13:58:28 -08:00
Pat Hickey
0909cf2660 tests: factor common HostMemory / MemArea code into a separate crate 2020-02-21 13:54:03 -08:00
Jakub Konka
f48474b247 Draft out IntDatatype in wiggle-generate (#15)
* Draft out IntDatatype in wiggle-generate

This commit drafts out basic layout for `IntDatatype` structure in
`wiggle`. As it currently stands, an `Int` type is represented as
a one-element tuple struct much like `FlagDatatype`, however, with
this difference that we do not perform any checks on the input
underlying representation since any value for the prescribed type
is legal.

* Finish drafting IntDatatype support in wiggle

This commit adds necessary marshal stubs to properly pass `IntDatatype`
in and out of interface functions. It also adds a basic proptest.
2020-02-21 22:53:10 +01:00
Jakub Konka
6ab3ff71d2 Add basic GuestString support to wiggle (#13)
* Add basic GuestString support to wiggle

This commit adds basic `GuestString` support to `wiggle`. `GuestString`
is a wrapper around `GuestArray<'_, u8>` array type which itself can
be made into either an owned (cloned) Rust `String` or borrowed as
a reference `&str`. In both cases, `GuestString` ensures that the
underlying bytes are valid Unicode code units, throwing a `InvalidUtf8`
error if not.

This commit adds support *only* for passing in strings as arguments
in WASI. Marshalling of the return arg has not yet been implemented.
I'm not even sure it's possible without multi-value return args
feature of Wasm. It's not a major setback especially since the WASI
spec (and this includes even the `ephemeral` snapshot) doesn't
return strings anywhere. They are only ever passed in as arguments
to interface functions.

It should be noted that error returned in case of invalid UTF-8
requires a lot more love as it doesn't include anything besides
flagging an event that the string contained an invalid Unicode code unit.

* Borrow all of string's memory including nul-byte

Borrow all of string's underlying memory including the nul-byte.
This perhaps might not have a tremendous impact on anything, but
since the nul-byte is technically part of the WASI string, we should
include it in the borrow as well.

* Fill in wiggle-generate blanks for strings

* Print to screen passed string in proptest

* Strings are PointerLengthPairs!

* Fix generation of strings in compound types

* Update test with simple string strategy

* Generate better test strings

* Finalise proptest for strings

* Fix formatting

* Update crates/runtime/src/memory/string.rs

Removes unnecessary comment in code

* Apply Pat's suggestion to wrap Utf8Error as error
2020-02-21 22:37:22 +01:00
Pat Hickey
2f223acc55 merge GuestTypePtr and GuestTypeClone into a single GuestTypeClone<'a> trait (#14)
* merge GuestTypePtr and GuestTypeClone into a single GuestTypeClone<'a> trait

* GuestArray can derive Clone (but not impl GuestTypeClone)

* fix array tests

* Fix GuestTypeClone for flags

Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>
2020-02-21 17:43:45 +01:00
Jakub Konka
3ef24a04fe Start drafting out flags datatype generation (#11)
* Adds support for flags datatype

This commit adds support for `FlagsDatatype`. In WASI, flags are
represented as bitfields/bitflags, therefore, it is important
for the type to have bitwise operations implemented, and some
way of checking whether the current set of flags contains some
other set (i.e., they intersect). Thus, this commit automatically
derives `BitAnd`, etc. for the derived flags datatype. It also
automatically provides an `ALL_FLAGS` value which corresponds to
a bitwise-or of all flag values present and is provided for
convenience.

* Simplify read_from_guest
2020-02-21 09:58:43 +01:00
Jakub Konka
898af8e2fb Revisit GuestArray and their deref mechanics
In preparation for landing `string` support in `wiggle`, I've
revisited `GuestArray` and the deref mechanics, and decided to
scrap the current approach in favour of the previous. Namely, for
`T: GuestTypeCopy` we provide `GuestArray::as_ref` which then can
be derefed directly to `&[T]` since the guest and host types have
matching representation, and for other types (thinking here of
our infamous arrays of pointers), I've instead added a way to
iterate over the pointers. Then, it is up to the `wiggle`'s client
to know whether they can deref whatever the pointer stored in array
is pointing at.
2020-02-20 23:16:53 +01:00
Jakub Konka
2ad77538f5 Add array generation to wiggle-generate crate (#9)
* Add array generation to wiggle-generate crate

This commit:
* adds array generation to `wiggle-generate` crate which implies
  that we can now generate arrays from `witx` files
* introduces two test interface functions `foo::reduce_excuses` and
  `foo::populate_excuses`, and adds matching prop-tests
* adds an out-of-boundary check to `HostMemory::mem_area_strat` since
  now, given we're generating arrays for testing with an arbitrary
  but bounded number of elements, it is possible to violate the boundary
* refactors `Region::extend` to a new signature `extend(times: u32)`
  which multiplies the current pointer `len` by `times`
* fixes bug in `GuestArray::as_ref` and `GuestArrayMut::as_ref_mut` methods
  where we were not validating the first element (we always started the
  validation from the second element)

* Fix generation of arrays in witx

This commit fixes how `arrays` are auto-generated from `witx` files.
In particular, the changes include:
* Since by design every `array` in `witx` represents an immutable
  slab of memory, we will only ever operate on `GuestArray` in which
  case I've gone ahead and removed `GuestArrayMut` so as to unclutter
  the code somewhat. If we find ourselves in need for it in the future,
  I reckon it will be better to write it from scratch (since the codebase
  will inevitably evolve by then considerably) rather than maintaining an
  unused implementation.
* I've rewritten `GuestArrayRef<T>` to be a wrapper for `Vec<GuestRef<T>>`.
  Also, `GuestArray::as_ref` now borrows each underlying "element" of the
  array one-by-one rather than borrowing the entire chunk of memory at once.
  This change is motivated by the inability to coerce type parameter `T` in
  `GuestArray<T>` in more complicated cases such as arrays of guest pointers
  `GuestPtr<T>` to `*const T` for reuse in `std::slice::from_raw_parts` call.
  (In general, the size of Wasm32 pointer is 4 bytes, while

```
std::mem::size_of::<T>() == std::mem::size_of::<GuestPtr<S>>() == 16
```

  which is problematic; i.e., I can't see how I could properly extract guest
  pointers from slices of 4 bytes and at the same time not allocate.)
* I've augmented fuzz tests by (re-)defining two `array` types:

```
(typename $const_excuse_array (array (@witx const_pointer $excuse)))
(typename $excuse_array (array (@witx pointer $excuse)))
```

  This should hopefully emulate and test the `iovec` and `ciovec` arrays
  present in WASI spec.
2020-02-19 10:58:55 +01:00
Jakub Konka
48a218b5c5 Refactor naming and crates info (#8)
* Refactor naming and crates info

This commit:
* changes workspace crates to have a `wiggle_` prefix in names
* rename `memory` module of `wiggle-memory` crate to `runtime`
* fixes authors of all crates

* Rename wiggle memory crate to runtime
2020-02-13 22:40:42 +01:00
Jakub Konka
44584bccfc Refactor memory module
This commit refactors and reorganises the `memory.rs` module. Now,
it consists of two submodules: `memory::ptr` which contains `GuestPtr`
and `GuestRef` (and their mutable versions), and `memory::array` which
contains `GuestArray` and `GuestArrayRef` (and their mutable versions).

This commit also adds basic unit sanity tests for the `memory::ptr`
submodule.
2020-02-09 17:52:27 -08:00
Jakub Konka
664f7d38e0 Add first pass at GuestArray (#5)
* Add first pass at GuestArray

* Return &'a [T] instead of Vec<Refs>

Also, add a sanity test for `GuestArray`.

* Change approach in GuestArray::as_ref

The new approach should avoid unnecessary copying (does it?) by
iterating through the memory and firstly validating the guest pointers,
to then extracting the slice `&'a [T]` using the unsafe `slice::from_raw_parts`
fn.

* Redo implementation of GuestArray and GuestArrayMut

This commit:
* redos the impl of `as_ref` and `as_ref_mut` for `GuestArray` and
  `GuestArrayMut` structs in that they now return dynamically borrow
  checked `GuestArrayRef` and `GuestArrayRefMut` structs
* introduces `GuestArrayRef` and `GuestArrayRefMut` structs which
  perform dynamic borrow-checking of memory region at runtime, and
  can be derefed to `&[T]` and `&mut [T]`
* adds a few sanity checks for the introduced types

* Rename r#ref to ref_

* Add constructors for GuestArray and GuestArrayMut

This commit:
* adds constructors for `GuestArray` and `GuestArrayMut` both of
  which can now *only* be constructed from `GuestPtr::array` and
  `GuestPtrMut::array_mut` respectively
* changes `Region::extend` to extend the region by adding to the
  current `len` (avoids problem of asserting for > 0)
* implements `fmt::Debug` for most of memory types for easier testing
  (implementation is *not* enforced on the generic parameter `T` in
   the struct; rather, if `T` impls `fmt::Debug` then so does the
   memory type such as `GuestPtr<'_, T>`)
2020-02-07 08:27:21 +01:00
Jakub Konka
2687b01474 Refactor Region struct (#4)
* Add some basic sanity tests for Region

This commit adds some basic sanity tests for `overlap` method
of `Region`.

* Refactor overlaps method of Region struct

This commit refactors `Region::overlaps` method.

* Add some docs

* Assert Region's len is nonzero
2020-02-04 23:26:18 +01:00
Pat Hickey
67d2ce6d85 Refactor tests to use proptest (#6)
* generator: take an &mut GuestMemory

rather than pass the owned GuestMemory in, just give exclusive access
to it. Makes testing easier.

* tests: start transforming tests to check abi-level generated code as well

* finish lowering of test funcs

* tests: rename variables to more sensible names

* proptesting: reliably finds that we dont allow stuff to be right against end of memory!

* memory: fix off-by-one calc in GuestMemory::contains(&self, Region)

ty proptest!

also, refactored the Region::overlaps to be the same code but easier to
read.

* generator: better location information in GuestError

* testing: proptest generates memory areas, tests everything
2020-02-04 22:35:38 +01:00
Jakub Konka
e6cec049cb Add basic CI conf (#3)
* Add basic CI conf

* Pull in submodules in Rustfmt job

* Exclude WASI from workspace; fix name clash in memory crate

* Refactor CI conf
2020-02-03 09:59:09 +01:00
Jakub Konka
3d428b828f Add some (incomplete set) basic sanity end-to-end tests (#2)
* Add some (incomplete set) basic sanity end-to-end tests

This commit adds some (an incomplete set of) basic sanity end-to-end
tests. It uses `test.witx` to autogenerate types and module interface
functions (aka the syscalls), and tests their implementation. For
the host memory, it uses simplistic `&mut [u8]` where we have full
control of the addressing and contents.

* Add sanity test for baz interface func

This commit adds a sanity test for the `Foo::baz` interface func.

* Upcast start/len for Region to avoid overflow

* Reenable alignment checking for memory

* use an array to implement hostmemory

Co-authored-by: Pat Hickey <pat@moreproductive.org>
2020-02-03 07:38:48 +01:00
Pat Hickey
f321f05a98 use lifetimes on types that require it 2020-01-31 15:18:49 -08:00
Pat Hickey
29c3ef9d09 we now parse witx paths and the ctx type name in the macro invocation 2020-01-30 16:38:16 -08:00
Pat Hickey
0ba8e73184 change proc macro argument parsing to use syn 2020-01-30 14:29:53 -08:00
Pat Hickey
e2079c085d report which field a struct validation error occured in 2020-01-29 13:18:57 -08:00
Pat Hickey
814dd19488 structs that contain pointers work! 2020-01-28 18:17:48 -08:00
Pat Hickey
35d9373976 we now validate Copy structs 2020-01-28 16:34:34 -08:00
Pat Hickey
62e00434b0 structs implementing Copy are scaffolded out.
todo: need an unsafe method for casting pointers in order to validate
contents via recursive descent
2020-01-28 15:45:52 -08:00
Pat Hickey
373560b88a and now funcs work again 2020-01-27 20:28:27 -08:00
Pat Hickey
c780421c28 i think the memory model is fixed now? at least until arrays.... 2020-01-27 20:21:53 -08:00
Pat Hickey
ec456e9e50 new memory model. not quite complete 2020-01-27 18:20:47 -08:00
Pat Hickey
e6a4ae205c return values written to pointers! 2020-01-27 12:40:54 -08:00
Pat Hickey
a20ef36a49 multiple layers of pointers work! 2020-01-24 19:57:18 -08:00
Pat Hickey
020778b7da we can handle one layer of pointers! 2020-01-24 18:08:37 -08:00
Pat Hickey
e789033651 bugfix 2020-01-24 15:16:09 -08:00
Pat Hickey
42eca19b50 types: make the tryfrom/to impl for the abi type, not the signed variant 2020-01-24 15:12:51 -08:00
Pat Hickey
b6d342ccb5 some progress on marshalling args 2020-01-23 17:55:59 -08:00
Pat Hickey
b4f21752b0 generate a module trait and call it 2020-01-23 12:53:10 -08:00
Pat Hickey
cb24fd97c0 better error trait design 2020-01-23 11:21:04 -08:00
Pat Hickey
7cc0073a3e hmm my first idea was bad but not too bad 2020-01-22 21:03:24 -08:00
Pat Hickey
c05475b806 generate: now we have a way to do errors, i guess 2020-01-22 20:47:40 -08:00
Pat Hickey
97077954f8 enum generation: fill in GuestTypeCopy impl 2020-01-22 17:23:29 -08:00
Pat Hickey
aa5c5f7018 flesh out the guest type traits a bit further 2020-01-22 16:38:25 -08:00
Pat Hickey
b8feffe6e1 funcs get abi type definitions 2020-01-20 15:10:11 -08:00
Pat Hickey
9291495e57 put names all in one place. some stub code for funcs! 2020-01-19 19:33:41 -08:00
Pat Hickey
cd686915aa clear out a bunch of old code, reorganize 2020-01-19 18:46:16 -08:00
Pat Hickey
4c7b3e8685 import some other helpers from pat's crate
* parse the proc macro argument into a file path
* use a much simpler witx spec by default
2020-01-17 15:48:51 -08:00
Pat Hickey
0d47556cf7 import memory sub-crate 2020-01-17 15:41:19 -08:00
Jakub Konka
f24b0240ae Start tweaking original wig with Pat's suggestion 2020-01-17 19:30:37 +01:00
Jakub Konka
64f0793388 Fix incorrect hardcoded path to witx spec 2020-01-17 14:59:51 +01:00
Jakub Konka
6f6c6499c6 Set up machinery 2020-01-17 14:54:05 +01:00