diff options
Diffstat (limited to 'vendor/github.com/tetratelabs/wazero/experimental/memory.go')
-rw-r--r-- | vendor/github.com/tetratelabs/wazero/experimental/memory.go | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/experimental/memory.go b/vendor/github.com/tetratelabs/wazero/experimental/memory.go new file mode 100644 index 000000000..e379bf053 --- /dev/null +++ b/vendor/github.com/tetratelabs/wazero/experimental/memory.go @@ -0,0 +1,50 @@ +package experimental + +import ( + "context" + + "github.com/tetratelabs/wazero/internal/expctxkeys" +) + +// MemoryAllocator is a memory allocation hook, +// invoked to create a LinearMemory. +type MemoryAllocator interface { + // Allocate should create a new LinearMemory with the given specification: + // cap is the suggested initial capacity for the backing []byte, + // and max the maximum length that will ever be requested. + // + // Notes: + // - To back a shared memory, the address of the backing []byte cannot + // change. This is checked at runtime. Implementations should document + // if the returned LinearMemory meets this requirement. + Allocate(cap, max uint64) LinearMemory +} + +// MemoryAllocatorFunc is a convenience for defining inlining a MemoryAllocator. +type MemoryAllocatorFunc func(cap, max uint64) LinearMemory + +// Allocate implements MemoryAllocator.Allocate. +func (f MemoryAllocatorFunc) Allocate(cap, max uint64) LinearMemory { + return f(cap, max) +} + +// LinearMemory is an expandable []byte that backs a Wasm linear memory. +type LinearMemory interface { + // Reallocates the linear memory to size bytes in length. + // + // Notes: + // - To back a shared memory, Reallocate can't change the address of the + // backing []byte (only its length/capacity may change). + Reallocate(size uint64) []byte + // Free the backing memory buffer. + Free() +} + +// WithMemoryAllocator registers the given MemoryAllocator into the given +// context.Context. +func WithMemoryAllocator(ctx context.Context, allocator MemoryAllocator) context.Context { + if allocator != nil { + return context.WithValue(ctx, expctxkeys.MemoryAllocatorKey{}, allocator) + } + return ctx +} |