wasmer_engine/
engine.rs

1//! Engine trait and associated types.
2
3use crate::tunables::Tunables;
4use crate::{Artifact, DeserializeError};
5use loupe::MemoryUsage;
6use memmap2::Mmap;
7use std::path::Path;
8use std::sync::atomic::{AtomicUsize, Ordering::SeqCst};
9use std::sync::Arc;
10use wasmer_compiler::{CompileError, Target};
11use wasmer_types::FunctionType;
12use wasmer_vm::{VMCallerCheckedAnyfunc, VMFuncRef, VMSharedSignatureIndex};
13
14/// A unimplemented Wasmer `Engine`.
15///
16/// This trait is used by implementors to implement custom engines
17/// such as: Universal or Native.
18///
19/// The product that an `Engine` produces and consumes is the [`Artifact`].
20pub trait Engine: MemoryUsage {
21    /// Gets the target
22    fn target(&self) -> &Target;
23
24    /// Register a signature
25    fn register_signature(&self, func_type: &FunctionType) -> VMSharedSignatureIndex;
26
27    /// Register a function's data.
28    fn register_function_metadata(&self, func_data: VMCallerCheckedAnyfunc) -> VMFuncRef;
29
30    /// Lookup a signature
31    fn lookup_signature(&self, sig: VMSharedSignatureIndex) -> Option<FunctionType>;
32
33    /// Validates a WebAssembly module
34    fn validate(&self, binary: &[u8]) -> Result<(), CompileError>;
35
36    /// Compile a WebAssembly binary
37    fn compile(
38        &self,
39        binary: &[u8],
40        tunables: &dyn Tunables,
41    ) -> Result<Arc<dyn Artifact>, CompileError>;
42
43    /// Deserializes a WebAssembly module
44    ///
45    /// # Safety
46    ///
47    /// The serialized content must represent a serialized WebAssembly module.
48    unsafe fn deserialize(&self, bytes: &[u8]) -> Result<Arc<dyn Artifact>, DeserializeError>;
49
50    /// Deserializes a WebAssembly module from a path
51    ///
52    /// # Safety
53    ///
54    /// The file's content must represent a serialized WebAssembly module.
55    unsafe fn deserialize_from_file(
56        &self,
57        file_ref: &Path,
58    ) -> Result<Arc<dyn Artifact>, DeserializeError> {
59        let file = std::fs::File::open(file_ref)?;
60        let mmap = Mmap::map(&file)?;
61        self.deserialize(&mmap)
62    }
63
64    /// A unique identifier for this object.
65    ///
66    /// This exists to allow us to compare two Engines for equality. Otherwise,
67    /// comparing two trait objects unsafely relies on implementation details
68    /// of trait representation.
69    fn id(&self) -> &EngineId;
70
71    /// Clone the engine
72    fn cloned(&self) -> Arc<dyn Engine + Send + Sync>;
73}
74
75#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, MemoryUsage)]
76#[repr(transparent)]
77/// A unique identifier for an Engine.
78pub struct EngineId {
79    id: usize,
80}
81
82impl EngineId {
83    /// Format this identifier as a string.
84    pub fn id(&self) -> String {
85        format!("{}", &self.id)
86    }
87}
88
89impl Clone for EngineId {
90    fn clone(&self) -> Self {
91        Self::default()
92    }
93}
94
95impl Default for EngineId {
96    fn default() -> Self {
97        static NEXT_ID: AtomicUsize = AtomicUsize::new(0);
98        Self {
99            id: NEXT_ID.fetch_add(1, SeqCst),
100        }
101    }
102}
wasmer_engine/engine.rs

wasmer_engine/
engine.rs
