func CdCmd(scp *variables.Scope, ioc *T.IOContainer, args []string) T.ExitStatus {
// This does not conform to the posix spec.
// Very simplified. Cd to first arg or attempt to cd to home dir
cdTarget := "."
if len(args) == 0 {
homeDir := scp.Get("HOME")
if homeDir.Val == "" {
// Implementation defined behaviour. We try to grab
// the homedir of the current user
u, err := user.Current()
if err == nil {
cdTarget = u.HomeDir
}
} else {
cdTarget = homeDir.Val
}
} else {
cdTarget = args[0]
}
if err := scp.SetPwd(cdTarget); err != nil {
fmt.Fprintf(os.Stderr, "%s\n", err.Error())
return T.ExitFailure
}
return T.ExitSuccess
}
func (s SubVariable) Sub(scp *variables.Scope) (returnString string) {
logex.Debug("Substituting variable")
defer func() {
logex.Debugf("Returned '%s'", returnString)
}()
v := scp.Get(s.VarName)
switch s.SubType {
case VarSubNormal:
return v.Val
case VarSubLength:
// For the values ${#*} and ${#@}
// the number of positional parameters is returned
// We need to perform IFS splitting to figure this out
return strconv.Itoa(len(v.Val))
}
varExists := v.Set == true
// CheckNull means that an empty string is treated as unset
if s.CheckNull {
varExists = varExists && v.Val != ""
}
switch s.SubType {
case VarSubAssign:
if varExists {
return v.Val
}
scp.Set(s.VarName, s.SubVal)
return s.SubVal
case VarSubMinus:
if varExists {
return v.Val
}
return s.SubVal
case VarSubPlus:
if varExists {
return ""
}
return s.SubVal
case VarSubQuestion:
if varExists {
return v.Val
}
if s.SubVal != "" {
ExitShellWithMessage(T.ExitFailure, s.SubVal)
}
ExitShellWithMessage(T.ExitFailure, s.VarName+": Parameter not set")
case VarSubTrimRight, VarSubTrimRightMax, VarSubTrimLeft, VarSubTrimLeftMax:
ExitShellWithMessage(T.ExitFailure, "Trim operations not implemented")
}
logex.Fatal("SubVariable.Sub unreached")
return ""
}
func LocalCmd(scp *variables.Scope, ioc *T.IOContainer, args []string) T.ExitStatus {
// Local should also do assignments, split args on equal sign? already
// expanded
for _, a := range args {
tmp := scp.Get(a)
if tmp.Set {
scp.Set(a, tmp.Val, variables.LocalScope)
} else {
scp.Set(a, "", variables.LocalScope)
}
}
return T.ExitSuccess
}