Add IPNetSlice (#15)

Author: cornfeedhobo

ipnet_slice.go

@@ -0,0 +1,176 @@
+package pflag
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"strings"
+)
+
+// -- ipNetSlice Value
+type ipNetSliceValue struct {
+	value   *[]net.IPNet
+	changed bool
+}
+
+func newIPNetSliceValue(val []net.IPNet, p *[]net.IPNet) *ipNetSliceValue {
+	ipnsv := new(ipNetSliceValue)
+	ipnsv.value = p
+	*ipnsv.value = val
+	return ipnsv
+}
+
+// Set converts, and assigns, the comma-separated IPNet argument string representation as the []net.IPNet value of this flag.
+// If Set is called on a flag that already has a []net.IPNet assigned, the newly converted values will be appended.
+func (s *ipNetSliceValue) Set(val string) error {
+
+	// remove all quote characters
+	rmQuote := strings.NewReplacer(`"`, "", `'`, "", "`", "")
+
+	// read flag arguments with CSV parser
+	ipNetStrSlice, err := readAsCSV(rmQuote.Replace(val))
+	if err != nil && err != io.EOF {
+		return err
+	}
+
+	// parse ip values into slice
+	out := make([]net.IPNet, 0, len(ipNetStrSlice))
+	for _, ipNetStr := range ipNetStrSlice {
+		_, n, err := net.ParseCIDR(strings.TrimSpace(ipNetStr))
+		if err != nil {
+			return fmt.Errorf("invalid string being converted to CIDR: %s", ipNetStr)
+		}
+		out = append(out, *n)
+	}
+
+	if !s.changed {
+		*s.value = out
+	} else {
+		*s.value = append(*s.value, out...)
+	}
+
+	s.changed = true
+
+	return nil
+}
+
+// Type returns a string that uniquely represents this flag's type.
+func (s *ipNetSliceValue) Type() string {
+	return "ipNetSlice"
+}
+
+// String defines a "native" format for this net.IPNet slice flag value.
+func (s *ipNetSliceValue) String() string {
+
+	ipNetStrSlice := make([]string, len(*s.value))
+	for i, n := range *s.value {
+		ipNetStrSlice[i] = n.String()
+	}
+
+	out, _ := writeAsCSV(ipNetStrSlice)
+	return "[" + out + "]"
+}
+
+func ipNetSliceConv(val string) (interface{}, error) {
+	val = strings.Trim(val, "[]")
+	// Emtpy string would cause a slice with one (empty) entry
+	if len(val) == 0 {
+		return []net.IPNet{}, nil
+	}
+	ss := strings.Split(val, ",")
+	out := make([]net.IPNet, len(ss))
+	for i, sval := range ss {
+		_, n, err := net.ParseCIDR(strings.TrimSpace(sval))
+		if err != nil {
+			return nil, fmt.Errorf("invalid string being converted to CIDR: %s", sval)
+		}
+		out[i] = *n
+	}
+	return out, nil
+}
+
+// GetIPNetSlice returns the []net.IPNet value of a flag with the given name
+func (f *FlagSet) GetIPNetSlice(name string) ([]net.IPNet, error) {
+	val, err := f.getFlagType(name, "ipNetSlice", ipNetSliceConv)
+	if err != nil {
+		return []net.IPNet{}, err
+	}
+	return val.([]net.IPNet), nil
+}
+
+// MustGetIPNetSlice is like GetIPNetSlice, but panics on error.
+func (f *FlagSet) MustGetIPNetSlice(name string) []net.IPNet {
+	val, err := f.GetIPNetSlice(name)
+	if err != nil {
+		panic(err)
+	}
+	return val
+}
+
+// IPNetSliceVar defines a ipNetSlice flag with specified name, default value, and usage string.
+// The argument p points to a []net.IPNet variable in which to store the value of the flag.
+func (f *FlagSet) IPNetSliceVar(p *[]net.IPNet, name string, value []net.IPNet, usage string) {
+	f.IPNetSliceVarP(p, name, "", value, usage)
+}
+
+// IPNetSliceVarP is like IPNetSliceVar, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) IPNetSliceVarP(p *[]net.IPNet, name, shorthand string, value []net.IPNet, usage string) {
+	f.VarP(newIPNetSliceValue(value, p), name, shorthand, usage)
+}
+
+// IPNetSliceVarS is like IPNetSliceVar, but accepts a shorthand letter that can be used after a single dash, alone.
+func (f *FlagSet) IPNetSliceVarS(p *[]net.IPNet, name, shorthand string, value []net.IPNet, usage string) {
+	f.VarS(newIPNetSliceValue(value, p), name, shorthand, usage)
+}
+
+// IPNetSliceVar defines a []net.IPNet flag with specified name, default value, and usage string.
+// The argument p points to a []net.IPNet variable in which to store the value of the flag.
+func IPNetSliceVar(p *[]net.IPNet, name string, value []net.IPNet, usage string) {
+	CommandLine.IPNetSliceVar(p, name, value, usage)
+}
+
+// IPNetSliceVarP is like IPNetSliceVar, but accepts a shorthand letter that can be used after a single dash.
+func IPNetSliceVarP(p *[]net.IPNet, name, shorthand string, value []net.IPNet, usage string) {
+	CommandLine.IPNetSliceVarP(p, name, shorthand, value, usage)
+}
+
+// IPNetSliceVarS is like IPNetSliceVar, but accepts a shorthand letter that can be used after a single dash, alone.
+func IPNetSliceVarS(p *[]net.IPNet, name, shorthand string, value []net.IPNet, usage string) {
+	CommandLine.IPNetSliceVarS(p, name, shorthand, value, usage)
+}
+
+// IPNetSlice defines a []net.IPNet flag with specified name, default value, and usage string.
+// The return value is the address of a []net.IPNet variable that stores the value of that flag.
+func (f *FlagSet) IPNetSlice(name string, value []net.IPNet, usage string) *[]net.IPNet {
+	return f.IPNetSliceP(name, "", value, usage)
+}
+
+// IPNetSliceP is like IPNetSlice, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) IPNetSliceP(name, shorthand string, value []net.IPNet, usage string) *[]net.IPNet {
+	p := []net.IPNet{}
+	f.IPNetSliceVarP(&p, name, shorthand, value, usage)
+	return &p
+}
+
+// IPNetSliceS is like IPNetSlice, but accepts a shorthand letter that can be used after a single dash, alone.
+func (f *FlagSet) IPNetSliceS(name, shorthand string, value []net.IPNet, usage string) *[]net.IPNet {
+	p := []net.IPNet{}
+	f.IPNetSliceVarS(&p, name, shorthand, value, usage)
+	return &p
+}
+
+// IPNetSlice defines a []net.IPNet flag with specified name, default value, and usage string.
+// The return value is the address of a []net.IP variable that stores the value of the flag.
+func IPNetSlice(name string, value []net.IPNet, usage string) *[]net.IPNet {
+	return CommandLine.IPNetSlice(name, value, usage)
+}
+
+// IPNetSliceP is like IPNetSlice, but accepts a shorthand letter that can be used after a single dash.
+func IPNetSliceP(name, shorthand string, value []net.IPNet, usage string) *[]net.IPNet {
+	return CommandLine.IPNetSliceP(name, shorthand, value, usage)
+}
+
+// IPNetSliceS is like IPNetSlice, but accepts a shorthand letter that can be used after a single dash, alone.
+func IPNetSliceS(name, shorthand string, value []net.IPNet, usage string) *[]net.IPNet {
+	return CommandLine.IPNetSliceS(name, shorthand, value, usage)
+}