diff options
Diffstat (limited to 'accounts/abi/method.go')
| -rw-r--r-- | accounts/abi/method.go | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/accounts/abi/method.go b/accounts/abi/method.go index 206c7d408..f3d1a44b5 100644 --- a/accounts/abi/method.go +++ b/accounts/abi/method.go @@ -18,6 +18,7 @@ package abi import ( "fmt" + "reflect" "strings" "github.com/ethereum/go-ethereum/crypto" @@ -38,6 +39,44 @@ type Method struct { Outputs []Argument } +func (m Method) pack(method Method, args ...interface{}) ([]byte, error) { + // Make sure arguments match up and pack them + if len(args) != len(method.Inputs) { + return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(method.Inputs)) + } + // variable input is the output appended at the end of packed + // output. This is used for strings and bytes types input. + var variableInput []byte + + var ret []byte + for i, a := range args { + input := method.Inputs[i] + // pack the input + packed, err := input.Type.pack(reflect.ValueOf(a)) + if err != nil { + return nil, fmt.Errorf("`%s` %v", method.Name, err) + } + + // check for a slice type (string, bytes, slice) + if input.Type.requiresLengthPrefix() { + // calculate the offset + offset := len(method.Inputs)*32 + len(variableInput) + // set the offset + ret = append(ret, packNum(reflect.ValueOf(offset), UintTy)...) + // Append the packed output to the variable input. The variable input + // will be appended at the end of the input. + variableInput = append(variableInput, packed...) + } else { + // append the packed value to the input + ret = append(ret, packed...) + } + } + // append the variable input at the end of the packed input + ret = append(ret, variableInput...) + + return ret, nil +} + // Sig returns the methods string signature according to the ABI spec. // // Example |