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-rw-r--r--vendor/github.com/tetratelabs/wazero/internal/wasm/binary/global.go50
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/global.go b/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/global.go
new file mode 100644
index 000000000..4e1c16fda
--- /dev/null
+++ b/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/global.go
@@ -0,0 +1,50 @@
+package binary
+
+import (
+ "bytes"
+ "fmt"
+
+ "github.com/tetratelabs/wazero/api"
+ "github.com/tetratelabs/wazero/internal/wasm"
+)
+
+// decodeGlobal returns the api.Global decoded with the WebAssembly 1.0 (20191205) Binary Format.
+//
+// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#binary-global
+func decodeGlobal(r *bytes.Reader, enabledFeatures api.CoreFeatures, ret *wasm.Global) (err error) {
+ ret.Type, err = decodeGlobalType(r)
+ if err != nil {
+ return err
+ }
+
+ err = decodeConstantExpression(r, enabledFeatures, &ret.Init)
+ return
+}
+
+// decodeGlobalType returns the wasm.GlobalType decoded with the WebAssembly 1.0 (20191205) Binary Format.
+//
+// See https://www.w3.org/TR/2019/REC-wasm-core-1-20191205/#binary-globaltype
+func decodeGlobalType(r *bytes.Reader) (wasm.GlobalType, error) {
+ vt, err := decodeValueTypes(r, 1)
+ if err != nil {
+ return wasm.GlobalType{}, fmt.Errorf("read value type: %w", err)
+ }
+
+ ret := wasm.GlobalType{
+ ValType: vt[0],
+ }
+
+ b, err := r.ReadByte()
+ if err != nil {
+ return wasm.GlobalType{}, fmt.Errorf("read mutablity: %w", err)
+ }
+
+ switch mut := b; mut {
+ case 0x00: // not mutable
+ case 0x01: // mutable
+ ret.Mutable = true
+ default:
+ return wasm.GlobalType{}, fmt.Errorf("%w for mutability: %#x != 0x00 or 0x01", ErrInvalidByte, mut)
+ }
+ return ret, nil
+}