44 lines
973 B
Go
44 lines
973 B
Go
package binary
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
|
|
"github.com/tetratelabs/wabin/wasm"
|
|
)
|
|
|
|
// decodeMemory returns the wasm.Memory decoded with the WebAssembly
|
|
// Binary Format.
|
|
//
|
|
// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#binary-memory
|
|
func decodeMemory(r *bytes.Reader) (*wasm.Memory, error) {
|
|
min, maxP, err := decodeLimitsType(r)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
mem := &wasm.Memory{Min: min}
|
|
if maxP != nil {
|
|
mem.Max = *maxP
|
|
mem.IsMaxEncoded = true
|
|
|
|
if min > mem.Max {
|
|
return nil, fmt.Errorf("min %d pages (%s) > max %d pages (%s)",
|
|
min, wasm.PagesToUnitOfBytes(min), mem.Max, wasm.PagesToUnitOfBytes(mem.Max))
|
|
}
|
|
}
|
|
|
|
return mem, nil
|
|
}
|
|
|
|
// encodeMemory returns the wasm.Memory encoded in WebAssembly Binary Format.
|
|
//
|
|
// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#binary-memory
|
|
func encodeMemory(i *wasm.Memory) []byte {
|
|
maxPtr := &i.Max
|
|
if !i.IsMaxEncoded {
|
|
maxPtr = nil
|
|
}
|
|
return encodeLimitsType(i.Min, maxPtr)
|
|
}
|