Crate wasmparser

A simple event-driven library for parsing WebAssembly binary files (or streams).

The parser library reports events as they happen and only stores parsing information for a brief period of time, making it very fast and memory-efficient. The event-driven model, however, has some drawbacks. If you need random access to the entire WebAssembly data-structure, this is not the right library for you. You could however, build such a data-structure using this library.

To get started, create a Parser using Parser::new and then follow the examples documented for Parser::parse or Parser::parse_all.

Modules

• collectionsvalidate
  Type definitions for maps and sets used by the wasmparser crate.
• component_typesvalidate and component-model
  Types relating to type information provided by validation.
• namesvalidate and component-model
  Definitions of name-related helpers and newtypes, primarily for the component model.
• typesvalidate
  Types relating to type information provided by validation.

Macros

• for_each_operator
  Used to implement routines for the Operator enum.
• for_each_visit_operator
  Used to implement the VisitOperator trait.
• for_each_visit_simd_operatorsimd
  Used to implement the VisitSimdOperator trait.

Structs

• ArrayType
  Represents a type of an array in a WebAssembly module.
• BinaryReader
  A binary reader of the WebAssembly structures and types.
• BinaryReaderError
  A binary reader for WebAssembly modules.
• BrTable
  A br_table entries representation.
• BranchHint
  A hint for a single branch.
• BranchHintFunction
  Branch hints for a single function.
• Comdat
  Represents COMDAT data in the linking custom section.
• ComdatSymbol
  Represents a symbol that is part of a comdat.
• ComponentExportcomponent-model
  Represents an export in a WebAssembly component.
• ComponentExportNamecomponent-model
  Represents the name of a component export.
• ComponentFuncTypecomponent-model
  Represents a type of a function in a WebAssembly component.
• ComponentImportcomponent-model
  Represents an import in a WebAssembly component
• ComponentImportNamecomponent-model
  Represents the name of a component import.
• ComponentInstantiationArgcomponent-model
  Represents an argument to instantiating a WebAssembly component.
• ComponentStartFunctioncomponent-model
  Represents the start function in a WebAssembly component.
• CompositeType
  Represents a composite type in a WebAssembly module.
• ConstExpr
  Represents an initialization expression.
• ContType
  Represents a type of a continuation in a WebAssembly module.
• CoreDumpInstance
  A single instance from a coredump instances section
• CoreDumpInstancesSection
  A custom section representing the instances involved in a given coredump
• CoreDumpModulesSection
  The data portion of a “coremodules” custom section. This contains a vec of module names that will be referenced by index by other coredump sections.
• CoreDumpSection
  The data portion of a custom section representing a core dump. Per the tool-conventions repo, this section just specifies the executable name that the core dump came from while the rest of the core dump information is contained in a corestack custom section
• CoreDumpStackFrame
  A single stack frame from a core dump
• CoreDumpStackSection
  The data portion of a custom section representing a core dump stack. The structure of this follows the coredump spec in the tool-conventions repo
• CustomSectionReader
  A reader for custom sections of a WebAssembly module.
• Data
  Represents a data segment in a core WebAssembly module.
• DefinedDataSymbol
  Represents the metadata about a data symbol defined in the wasm file.
• Element
  Represents a core WebAssembly element segment.
• Export
  Represents an export in a WebAssembly module.
• ExportInfo
• FieldType
  Represents a field type of an array or a struct.
• Framevalidate
  A Wasm control flow block on the control flow stack during Wasm validation.
• FuncToValidatevalidate
  Resources necessary to perform validation of a function.
• FuncType
  Represents a type of a function in a WebAssembly module.
• FuncValidatorvalidate
  Validation context for a WebAssembly function.
• FuncValidatorAllocationsvalidate
  External handle to the internal allocations used during function validation.
• FunctionBody
  Represents a WebAssembly function body.
• Global
  Represents a core WebAssembly global.
• GlobalType
  Represents a global’s type.
• Ieee32
  An IEEE binary32 immediate floating point value, represented as a u32 containing the bit pattern.
• Ieee64
  An IEEE binary64 immediate floating point value, represented as a u64 containing the bit pattern.
• Import
  Represents an import in a WebAssembly module.
• ImportInfo
• IndirectNaming
  Represents an indirect name in the names custom section.
• InitFunc
  Represents an init function in the linking custom section.
• InstantiationArgcomponent-model
  Represents an argument to instantiating a WebAssembly module.
• LinkingSectionReader
  A reader for the linking custom section of a WebAssembly module.
• LocalsIterator
  An iterator over locals in a function body.
• LocalsReader
  A reader for a function body’s locals.
• MemArg
  Represents a memory immediate in a WebAssembly memory instruction.
• MemInfo
  Represents a WASM_DYLINK_MEM_INFO field
• MemoryType
  Represents a memory’s type.
• Naming
  Represents a name for an index from the names section.
• OperatorsIterator
  An iterator over a function’s operators.
• OperatorsIteratorWithOffsets
  An iterator over a function’s operators with offsets.
• OperatorsReader
  A reader for a core WebAssembly function’s operators.
• PackedIndex
  A packed representation of a type index.
• Parser
  An incremental parser of a binary WebAssembly module or component.
• ProducersField
  A field from the producers custom section.
• ProducersFieldValue
  Represents a field value in the producers custom section.
• RecGroup
  Represents a recursive type group in a WebAssembly module.
• RefType
  A reference type.
• RelocSectionReader
  Reader for reloc.* sections as defined by https://github.com/WebAssembly/tool-conventions/blob/main/Linking.md#relocation-sections.
• RelocationEntry
  Single relocation entry within a reloc.* section, as defined at https://github.com/WebAssembly/tool-conventions/blob/main/Linking.md#relocation-sections.
• ResumeTable
  A representation of dispatch tables on resume and resume_throw instructions.
• SectionLimited
  A generic structure for reading a section of a WebAssembly binary which has a limited number of items within it.
• SectionLimitedIntoIter
  A consuming iterator of a SectionLimited.
• SectionLimitedIntoIterWithOffsets
  An iterator over a limited section iterator.
• Segment
  Represents extra metadata about the data segments.
• SegmentFlags
  Flags for WebAssembly segments.
• StructType
  Represents a type of a struct in a WebAssembly module.
• SubType
  Represents a subtype of possible other types in a WebAssembly module.
• Subsections
  Iterator/reader over the contents of a section which is composed of subsections.
• SymbolFlags
  Flags for WebAssembly symbols.
• Table
  Type information about a table defined in the table section of a WebAssembly module.
• TableType
  Represents a table’s type.
• TagType
  A tag’s type.
• TryTable
  A try_table entries representation.
• V128
  Represents a 128-bit vector value.
• Validatorvalidate
  Validator for a WebAssembly binary module or component.
• ValidatorIdvalidate
  A unique identifier for a particular Validator.
• ValidatorResourcesvalidate
  The implementation of WasmModuleResources used by Validator.
• VariantCasecomponent-model
  Represents a case in a variant type.
• WasmFeatures
  Flags for features that are enabled for validation.
• WasmFeaturesInflatedfeatures
  Inflated version of WasmFeatures that allows for exhaustive matching on fields.

Enums

• AbstractHeapType
  An abstract heap type.
• BlockType
  Represents a block type.
• CanonicalFunctioncomponent-model
  Represents a canonical function in a WebAssembly component.
• CanonicalOptioncomponent-model
  Represents options for component functions.
• Catch
  Catch clauses that can be specified in TryTable.
• Chunk
  A successful return payload from Parser::parse.
• ComdatSymbolKind
  Represents a symbol kind.
• ComponentAliascomponent-model
  Represents an alias in a WebAssembly component.
• ComponentDefinedTypecomponent-model
  Represents a defined type in a WebAssembly component.
• ComponentExternalKindcomponent-model
  Represents the kind of an external items of a WebAssembly component.
• ComponentFuncResultcomponent-model
  Represents the result type of a component function.
• ComponentInstancecomponent-model
  Represents an instance in a WebAssembly component.
• ComponentNamecomponent-model
  Represents a name read from the names custom section.
• ComponentOuterAliasKindcomponent-model
  Represents the kind of an outer alias in a WebAssembly component.
• ComponentTypecomponent-model
  Represents a type in a WebAssembly component.
• ComponentTypeDeclarationcomponent-model
  Represents part of a component type declaration in a WebAssembly component.
• ComponentTypeRefcomponent-model
  Represents a reference to a component type.
• ComponentValTypecomponent-model
  Represents a value type in a WebAssembly component.
• CompositeInnerType
  A CompositeType can contain one of these types.
• CoreDumpValue
  Local and stack values are encoded using one byte for the type (similar to Wasm’s Number Types) followed by bytes representing the actual value See the tool-conventions repo for more details.
• CoreTypecomponent-model
  Represents a core type in a WebAssembly component.
• DataKind
  The kind of data segment.
• Dylink0Subsection
  Possible subsections of the dylink.0 custom section.
• ElementItems
  Represents the items of an element segment.
• ElementKind
  The kind of element segment.
• Encoding
  The supported encoding formats for the parser.
• ExternalKind
  External types as defined here.
• FrameKind
  The kind of a control flow Frame.
• Handle
  Handle clauses that can be specified in ResumeTable.
• HeapType
  A heap type.
• Instancecomponent-model
  Represents an instance of a WebAssembly module.
• InstanceTypeDeclarationcomponent-model
  Represents an instance type declaration in a WebAssembly component.
• InstantiationArgKindcomponent-model
  Represents the kind of an instantiation argument for a core instance.
• KnownCustom
  Return value of CustomSectionReader::as_known.
• Linking
  Represents a subsection read from the linking custom section.
• ModuleTypeDeclarationcomponent-model
  Represents a module type declaration in a WebAssembly component.
• Name
  Represents a name read from the names custom section.
• Operator
  Instructions as defined here.
• Ordering
  Represents the memory ordering for atomic instructions.
• OuterAliasKindcomponent-model
  Represents the kind of an outer core alias in a WebAssembly component.
• Payload
  Values that can be parsed from a WebAssembly module or component.
• PrimitiveValTypecomponent-model
  Represents a primitive value type.
• RelocAddendKind
  Indicates the kind of addend that applies to a relocation entry.
• RelocationType
  Relocation entry type. Each entry type corresponds to one of the R_WASM_* constants defined at https://github.com/llvm/llvm-project/blob/main/llvm/include/llvm/BinaryFormat/WasmRelocs.def and https://github.com/WebAssembly/tool-conventions/blob/main/Linking.md#relocation-sections.
• StorageType
  Represents storage types introduced in the GC spec for array and struct fields.
• SymbolInfo
  Represents extra information about symbols in the linking custom section.
• TableInit
  Different modes of initializing a table.
• TagKind
  Represents a tag kind.
• TypeBoundscomponent-model
  Represents the type bounds for imports and exports.
• TypeRef
  Represents a reference to a type definition in a WebAssembly module.
• UnpackedIndex
  The uncompressed form of a PackedIndex.
• ValType
  Represents the types of values in a WebAssembly module.
• ValidPayloadvalidate
  Possible return values from Validator::payload.

Traits

• FromReader
  A trait implemented for items that can be decoded directly from a BinaryReader, or that which can be parsed from the WebAssembly binary format.
• ModuleArity
  To compute the arity (param and result counts) of “variable-arity” operators, the operator_arity macro needs information about the module’s types and the current control stack. The ModuleArity trait exposes this information.
• Subsection
  A trait implemented for subsections of another outer section.
• VisitOperator
  Trait implemented by types that can visit all Operator variants.
• VisitSimdOperatorsimd
  Trait implemented by types that can visit all Wasm simd and relaxed-simd Operators.
• WasmModuleResourcesvalidate
  Types that qualify as Wasm validation database.

Functions

• validatevalidate
  Test whether the given buffer contains a valid WebAssembly module or component, analogous to WebAssembly.validate in the JS API.

Type Aliases

• BranchHintSectionReader
  A reader for the metadata.code.branch_hint custom section.
• CodeSectionReader
  A reader for the code section of a WebAssembly module.
• ComdatMap
  Represents a reader for COMDAT data from the linking custom section.
• ComponentAliasSectionReadercomponent-model
  Section reader for the component alias section
• ComponentCanonicalSectionReadercomponent-model
  A reader for the canonical section of a WebAssembly component.
• ComponentExportSectionReadercomponent-model
  A reader for the export section of a WebAssembly component.
• ComponentImportSectionReadercomponent-model
  A reader for the import section of a WebAssembly component.
• ComponentInstanceSectionReadercomponent-model
  A reader for the component instance section of a WebAssembly component.
• ComponentNameSectionReadercomponent-model
  Type used to iterate and parse the contents of the component-name custom section in compnents, similar to the name section of core modules.
• ComponentTypeSectionReadercomponent-model
  A reader for the type section of a WebAssembly component.
• CoreTypeSectionReadercomponent-model
  A reader for the core type section of a WebAssembly component.
• DataSectionReader
  A reader for the data section of a WebAssembly module.
• Dylink0SectionReader
  Parser for the dynamic linking dylink.0 custom section.
• ElementSectionReader
  A reader for the element section of a WebAssembly module.
• ExportSectionReader
  A reader for the export section of a WebAssembly module.
• FunctionSectionReader
  A reader for the function section of a WebAssembly module.
• GlobalSectionReader
  A reader for the global section of a WebAssembly module.
• ImportSectionReader
  A reader for the import section of a WebAssembly module.
• IndirectNameMap
  Represents a reader for indirect names from the names custom section.
• InitFuncMap
  Represents a reader for init functions from the linking custom section.
• InstanceSectionReadercomponent-model
  A reader for the core instance section of a WebAssembly component.
• MemorySectionReader
  A reader for the memory section of a WebAssembly module.
• NameMap
  Represents a name map from the names custom section.
• NameSectionReader
  A reader for the name custom section of a WebAssembly module.
• ProducersSectionReader
  A reader for the producers custom section of a WebAssembly module.
• RelocationEntryReader
  Reader for relocation entries within a reloc.* section.
• Result
  The result for BinaryReader operations.
• SegmentMap
  Represents a reader for segments from the linking custom section.
• SymbolInfoMap
  Represents a reader for symbol info from the linking custom section.
• TableSectionReader
  A reader for the table section of a WebAssembly module.
• TagSectionReader
  A reader for the tags section of a WebAssembly module.
• TypeSectionReader
  A reader for the type section of a WebAssembly module.