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-rw-r--r--vendor/github.com/tetratelabs/wazero/internal/wasm/binary/value.go60
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/value.go b/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/value.go
new file mode 100644
index 000000000..755ee5ea3
--- /dev/null
+++ b/vendor/github.com/tetratelabs/wazero/internal/wasm/binary/value.go
@@ -0,0 +1,60 @@
+package binary
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "unicode/utf8"
+ "unsafe"
+
+ "github.com/tetratelabs/wazero/internal/leb128"
+ "github.com/tetratelabs/wazero/internal/wasm"
+)
+
+func decodeValueTypes(r *bytes.Reader, num uint32) ([]wasm.ValueType, error) {
+ if num == 0 {
+ return nil, nil
+ }
+
+ ret := make([]wasm.ValueType, num)
+ _, err := io.ReadFull(r, ret)
+ if err != nil {
+ return nil, err
+ }
+
+ for _, v := range ret {
+ switch v {
+ case wasm.ValueTypeI32, wasm.ValueTypeF32, wasm.ValueTypeI64, wasm.ValueTypeF64,
+ wasm.ValueTypeExternref, wasm.ValueTypeFuncref, wasm.ValueTypeV128:
+ default:
+ return nil, fmt.Errorf("invalid value type: %d", v)
+ }
+ }
+ return ret, nil
+}
+
+// decodeUTF8 decodes a size prefixed string from the reader, returning it and the count of bytes read.
+// contextFormat and contextArgs apply an error format when present
+func decodeUTF8(r *bytes.Reader, contextFormat string, contextArgs ...interface{}) (string, uint32, error) {
+ size, sizeOfSize, err := leb128.DecodeUint32(r)
+ if err != nil {
+ return "", 0, fmt.Errorf("failed to read %s size: %w", fmt.Sprintf(contextFormat, contextArgs...), err)
+ }
+
+ if size == 0 {
+ return "", uint32(sizeOfSize), nil
+ }
+
+ buf := make([]byte, size)
+ if _, err = io.ReadFull(r, buf); err != nil {
+ return "", 0, fmt.Errorf("failed to read %s: %w", fmt.Sprintf(contextFormat, contextArgs...), err)
+ }
+
+ if !utf8.Valid(buf) {
+ return "", 0, fmt.Errorf("%s is not valid UTF-8", fmt.Sprintf(contextFormat, contextArgs...))
+ }
+
+ // TODO: use unsafe.String after flooring Go 1.20.
+ ret := *(*string)(unsafe.Pointer(&buf))
+ return ret, size + uint32(sizeOfSize), nil
+}