syncthing/vendor/github.com/calmh/xdr/common.go
Jakob Borg 65aaa607ab Use Go 1.5 vendoring instead of Godeps
Change made by:

- running "gvt fetch" on each of the packages mentioned in
  Godeps/Godeps.json
- `rm -rf Godeps`
- tweaking the build scripts to not mention Godeps
- tweaking the build scripts to test `./lib/...`, `./cmd/...` explicitly
  (to avoid testing vendor)
- tweaking the build scripts to not juggle GOPATH for Godeps and instead
  set GO15VENDOREXPERIMENT.

This also results in some updated packages at the same time I bet.

Building with Go 1.3 and 1.4 still *works* but won't use our vendored
dependencies - the user needs to have the actual packages in their
GOPATH then, which they'll get with a normal "go get". Building with Go
1.6+ will get our vendored dependencies by default even when not using
our build script, which is nice.

By doing this we gain some freedom in that we can pick and choose
manually what to include in vendor, as it's not based on just dependency
analysis of our own code. This is also a risk as we might pick up
dependencies we are unaware of, as the build may work locally with those
packages present in GOPATH. On the other hand the build server will
detect this as it has no packages in it's GOPATH beyond what is included
in the repo.

Recommended tool to manage dependencies is github.com/FiloSottile/gvt.
2016-03-05 21:21:24 +01:00

60 lines
1.5 KiB
Go

// Copyright (C) 2014 Jakob Borg. All rights reserved. Use of this source code
// is governed by an MIT-style license that can be found in the LICENSE file.
package xdr
import (
"fmt"
"reflect"
)
var padBytes = []byte{0, 0, 0}
// Pad returns the number of bytes that should be added to an item of length l
// bytes to conform to the XDR padding standard. This function is used by the
// generated marshalling code.
func Padding(l int) int {
d := l % 4
if d == 0 {
return 0
}
return 4 - d
}
// ElementSizeExceeded returns an error describing the violated size
// constraint. This function is used by the generated marshalling code.
func ElementSizeExceeded(field string, size, limit int) error {
return fmt.Errorf("%s exceeds size limit; %d > %d", field, size, limit)
}
type XDRSizer interface {
XDRSize() int
}
// SizeOfSlice returns the XDR encoded size of the given []T. Supported types
// for T are string, []byte and types implementing XDRSizer. SizeOfSlice
// panics if the parameter is not a slice or if T is not one of the supported
// types. This function is used by the generated marshalling code.
func SizeOfSlice(ss interface{}) int {
l := 0
switch ss := ss.(type) {
case []string:
for _, s := range ss {
l += 4 + len(s) + Padding(len(s))
}
case [][]byte:
for _, s := range ss {
l += 4 + len(s) + Padding(len(s))
}
default:
v := reflect.ValueOf(ss)
for i := 0; i < v.Len(); i++ {
l += v.Index(i).Interface().(XDRSizer).XDRSize()
}
}
return l
}