Crate wasmtime_runtime

Runtime library support for Wasmtime.

Modules

• libcalls
  Runtime library calls.

Structs

• Backtrace
  A WebAssembly stack trace.
• CompiledModuleId
  A unique identifier (within an engine or similar) for a compiled module.
• CompiledModuleIdAllocator
  An allocator for compiled module IDs.
• DefaultMemoryCreator
  A default memory allocator used by Wasmtime
• ExportFunction
  A function export value.
• ExportGlobal
  A global export value.
• ExportMemory
  A memory export value.
• ExportTable
  A table export value.
• GdbJitImageRegistration
  Registeration for JIT image
• Imports
  Resolved import pointers.
• InstanceAllocationRequest
  Represents a request for a new runtime instance.
• InstanceHandle
  A handle holding an Instance of a WebAssembly module.
• InstanceLimits
  Represents the limits placed on instances by the pooling instance allocator.
• LinkError
  An link error while instantiating a module.
• Memory
  Representation of a runtime wasm linear memory.
• MemoryImage
  One backing image for one memory.
• MemoryImageSlot
  A single slot handled by the copy-on-write memory initialization mechanism.
• Mmap
  A simple struct consisting of a page-aligned pointer to page-aligned and initially-zeroed memory and a length.
• MmapVec
  A type akin to Vec<u8>, but backed by mmap and able to be split.
• ModuleMemoryImages
  Backing images for memories in a module.
• OnDemandInstanceAllocator
  Represents the on-demand instance allocator.
• PoolingInstanceAllocator
  Implements the pooling instance allocator.
• SharedMemory
  For shared memory (and only for shared memory), this lock-version restricts access when growing the memory or checking its size. This is to conform with the thread proposal: “When IsSharedArrayBuffer(...) is true, the return value should be the result of an atomic read-modify-write of the new size to the internal length slot.”
• StorePtr
  A pointer to a Store. This Option<*mut dyn Store> is wrapped in a struct so that the function to create a &mut dyn Store is a method on a member of InstanceAllocationRequest, rather than on a &mut InstanceAllocationRequest itself, because several use-sites require a split mut borrow on the InstanceAllocationRequest.
• TlsRestore
  Opaque state used to help control TLS state across stack switches for async support.
• Trap
  Stores trace message with backtrace.
• VMCallerCheckedAnyfunc
  The VM caller-checked “anyfunc” record, for caller-side signature checking. It consists of the actual function pointer and a signature id to be checked by the caller.
• VMContext
  The VM “context”, which is pointed to by the vmctx arg in Cranelift. This has information about globals, memories, tables, and other runtime state associated with the current instance.
• VMExternRef
  An external reference to some opaque data.
• VMExternRefActivationsTable
  A table that over-approximizes the set of VMExternRefs that any Wasm activation on this thread is currently using.
• VMFunctionBody
  A placeholder byte-sized type which is just used to provide some amount of type safety when dealing with pointers to JIT-compiled function bodies. Note that it’s deliberately not Copy, as we shouldn’t be carelessly copying function body bytes around.
• VMFunctionImport
  An imported function.
• VMGlobalDefinition
  The storage for a WebAssembly global defined within the instance.
• VMGlobalImport
  The fields compiled code needs to access to utilize a WebAssembly global variable imported from another instance.
• VMHostFuncContext
  The VM*Context for host functions.
• VMInvokeArgument
  The storage for a WebAssembly invocation argument
• VMMemoryDefinition
  The fields compiled code needs to access to utilize a WebAssembly linear memory defined within the instance, namely the start address and the size in bytes.
• VMMemoryImport
  The fields compiled code needs to access to utilize a WebAssembly linear memory imported from another instance.
• VMOpaqueContext
  An “opaque” version of VMContext which must be explicitly casted to a target context.
• VMRuntimeLimits
  Structure used to control interrupting wasm code.
• VMSharedSignatureIndex
  An index into the shared signature registry, usable for checking signatures at indirect calls.
• VMTableDefinition
  The fields compiled code needs to access to utilize a WebAssembly table defined within the instance.
• VMTableImport
  The fields compiled code needs to access to utilize a WebAssembly table imported from another instance.

Enums

• Export
  The value of an export passed from one instance to another.
• InstantiationError
  An error while instantiating a module.
• PoolingAllocationStrategy
  The allocation strategy to use for the pooling instance allocator.
• Table
  Represents an instance’s table.
• TableElement
  An element going into or coming out of a table.
• TrapReason
  Enumeration of different methods of raising a trap.

Constants

• VERSION
  Version number of this crate.

Traits

• InstanceAllocator
  Represents a runtime instance allocator.
• ModuleInfo
  Used by the runtime to query module information.
• ModuleInfoLookup
  Used by the runtime to lookup information about a module given a program counter value.
• ModuleRuntimeInfo
  Functionality required by this crate for a particular module. This is chiefly needed for lazy initialization of various bits of instance state.
• RuntimeLinearMemory
  A linear memory
• RuntimeMemoryCreator
  A memory allocator
• Store
  Dynamic runtime functionality needed by this crate throughout the execution of a wasm instance.

Functions

• allocate_single_memory_instance^⚠
  Allocate an instance containing a single memory.
• catch_traps^⚠
  Catches any wasm traps that happen within the execution of closure, returning them as a Result.
• gc^⚠
  Perform garbage collection of VMExternRefs.
• init_traps
  This function is required to be called before any WebAssembly is entered. This will configure global state such as signal handlers to prepare the process to receive wasm traps.
• page_size
  Returns the host OS page size, in bytes.
• prepare_host_to_wasm_trampoline^⚠
  Given a Wasm function pointer and a vmctx, prepare the vmctx for calling into that Wasm function, and return the host-to-Wasm entry trampoline.
• raise_lib_trap^⚠
  Raises a trap from inside library code immediately.
• raise_user_trap^⚠
  Raises a user-defined trap immediately.
• resume_panic^⚠
  Carries a Rust panic across wasm code and resumes the panic on the other side.
• tls_eager_initialize
  Eagerly initialize thread-local runtime functionality. This will be performed lazily by the runtime if users do not perform it eagerly.

Type Definitions

• SignalHandler
  For now this is basically unused, we don’t expose this any more for Wasmtime on macOS.
• VMTrampoline
  Type definition of the trampoline used to enter WebAssembly from the host.

Unions

• ValRaw
  A “raw” and unsafe representation of a WebAssembly value.