From 77c172b823b64ebface655681ab0749b9d2f7081 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ra=C3=BAl=20Benencia?= Date: Fri, 13 Apr 2018 16:30:31 -0700 Subject: First public commit --- vendor/github.com/namsral/flag/flag.go | 1068 ++++++++++++++++++++++++++++++++ 1 file changed, 1068 insertions(+) create mode 100644 vendor/github.com/namsral/flag/flag.go (limited to 'vendor/github.com/namsral/flag/flag.go') diff --git a/vendor/github.com/namsral/flag/flag.go b/vendor/github.com/namsral/flag/flag.go new file mode 100644 index 0000000..9ee1d9c --- /dev/null +++ b/vendor/github.com/namsral/flag/flag.go @@ -0,0 +1,1068 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/*Package flag implements command-line flag parsing. +okdaokddadok +Usage: + +Define flags using flag.String(), Bool(), Int(), etc. + +This declares an integer flag, -flagname, stored in the pointer ip, with type *int. + import "flag" + var ip = flag.Int("flagname", 1234, "help message for flagname") +If you like, you can bind the flag to a variable using the Var() functions. + var flagvar int + func init() { + flag.IntVar(&flagvar, "flagname", 1234, "help message for flagname") + } +Or you can create custom flags that satisfy the Value interface (with +pointer receivers) and couple them to flag parsing by + flag.Var(&flagVal, "name", "help message for flagname") +For such flags, the default value is just the initial value of the variable. + +After all flags are defined, call + flag.Parse() +to parse the command line into the defined flags. + +Flags may then be used directly. If you're using the flags themselves, +they are all pointers; if you bind to variables, they're values. + fmt.Println("ip has value ", *ip) + fmt.Println("flagvar has value ", flagvar) + +After parsing, the arguments after the flag are available as the +slice flag.Args() or individually as flag.Arg(i). +The arguments are indexed from 0 through flag.NArg()-1. + +Command line flag syntax: + -flag + -flag=x + -flag x // non-boolean flags only +One or two minus signs may be used; they are equivalent. +The last form is not permitted for boolean flags because the +meaning of the command + cmd -x * +will change if there is a file called 0, false, etc. You must +use the -flag=false form to turn off a boolean flag. + +Flag parsing stops just before the first non-flag argument +("-" is a non-flag argument) or after the terminator "--". + +Integer flags accept 1234, 0664, 0x1234 and may be negative. +Boolean flags may be 1, 0, t, f, true, false, TRUE, FALSE, True, False. +Duration flags accept any input valid for time.ParseDuration. + +The default set of command-line flags is controlled by +top-level functions. The FlagSet type allows one to define +independent sets of flags, such as to implement subcommands +in a command-line interface. The methods of FlagSet are +analogous to the top-level functions for the command-line +flag set. +*/ +package flag + +import ( + "bufio" + "errors" + "fmt" + "io" + "os" + "sort" + "strconv" + "strings" + "time" +) + +// EnvironmentPrefix defines a string that will be implicitely prefixed to a +// flag name before looking it up in the environment variables. +var EnvironmentPrefix = "" + +// DefaultConfigFlagname defines the flag name of the optional config file +// path. Used to lookup and parse the config file when a default is set and +// available on disk. +var DefaultConfigFlagname = "config" + +// ErrHelp is the error returned if the flag -help is invoked but no such flag is defined. +var ErrHelp = errors.New("flag: help requested") + +// -- bool Value +type boolValue bool + +func newBoolValue(val bool, p *bool) *boolValue { + *p = val + return (*boolValue)(p) +} + +func (b *boolValue) Set(s string) error { + v, err := strconv.ParseBool(s) + *b = boolValue(v) + return err +} + +func (b *boolValue) Get() interface{} { return bool(*b) } + +func (b *boolValue) String() string { return fmt.Sprintf("%v", *b) } + +func (b *boolValue) IsBoolFlag() bool { return true } + +// optional interface to indicate boolean flags that can be +// supplied without "=value" text +type boolFlag interface { + Value + IsBoolFlag() bool +} + +// -- int Value +type intValue int + +func newIntValue(val int, p *int) *intValue { + *p = val + return (*intValue)(p) +} + +func (i *intValue) Set(s string) error { + v, err := strconv.ParseInt(s, 0, 64) + *i = intValue(v) + return err +} + +func (i *intValue) Get() interface{} { return int(*i) } + +func (i *intValue) String() string { return fmt.Sprintf("%v", *i) } + +// -- int64 Value +type int64Value int64 + +func newInt64Value(val int64, p *int64) *int64Value { + *p = val + return (*int64Value)(p) +} + +func (i *int64Value) Set(s string) error { + v, err := strconv.ParseInt(s, 0, 64) + *i = int64Value(v) + return err +} + +func (i *int64Value) Get() interface{} { return int64(*i) } + +func (i *int64Value) String() string { return fmt.Sprintf("%v", *i) } + +// -- uint Value +type uintValue uint + +func newUintValue(val uint, p *uint) *uintValue { + *p = val + return (*uintValue)(p) +} + +func (i *uintValue) Set(s string) error { + v, err := strconv.ParseUint(s, 0, 64) + *i = uintValue(v) + return err +} + +func (i *uintValue) Get() interface{} { return uint(*i) } + +func (i *uintValue) String() string { return fmt.Sprintf("%v", *i) } + +// -- uint64 Value +type uint64Value uint64 + +func newUint64Value(val uint64, p *uint64) *uint64Value { + *p = val + return (*uint64Value)(p) +} + +func (i *uint64Value) Set(s string) error { + v, err := strconv.ParseUint(s, 0, 64) + *i = uint64Value(v) + return err +} + +func (i *uint64Value) Get() interface{} { return uint64(*i) } + +func (i *uint64Value) String() string { return fmt.Sprintf("%v", *i) } + +// -- string Value +type stringValue string + +func newStringValue(val string, p *string) *stringValue { + *p = val + return (*stringValue)(p) +} + +func (s *stringValue) Set(val string) error { + *s = stringValue(val) + return nil +} + +func (s *stringValue) Get() interface{} { return string(*s) } + +func (s *stringValue) String() string { return fmt.Sprintf("%s", *s) } + +// -- float64 Value +type float64Value float64 + +func newFloat64Value(val float64, p *float64) *float64Value { + *p = val + return (*float64Value)(p) +} + +func (f *float64Value) Set(s string) error { + v, err := strconv.ParseFloat(s, 64) + *f = float64Value(v) + return err +} + +func (f *float64Value) Get() interface{} { return float64(*f) } + +func (f *float64Value) String() string { return fmt.Sprintf("%v", *f) } + +// -- time.Duration Value +type durationValue time.Duration + +func newDurationValue(val time.Duration, p *time.Duration) *durationValue { + *p = val + return (*durationValue)(p) +} + +func (d *durationValue) Set(s string) error { + v, err := time.ParseDuration(s) + *d = durationValue(v) + return err +} + +func (d *durationValue) Get() interface{} { return time.Duration(*d) } + +func (d *durationValue) String() string { return (*time.Duration)(d).String() } + +// Value is the interface to the dynamic value stored in a flag. +// (The default value is represented as a string.) +// +// If a Value has an IsBoolFlag() bool method returning true, +// the command-line parser makes -name equivalent to -name=true +// rather than using the next command-line argument. +type Value interface { + String() string + Set(string) error +} + +// Getter is an interface that allows the contents of a Value to be retrieved. +// It wraps the Value interface, rather than being part of it, because it +// appeared after Go 1 and its compatibility rules. All Value types provided +// by this package satisfy the Getter interface. +type Getter interface { + Value + Get() interface{} +} + +// ErrorHandling defines how to handle flag parsing errors. +type ErrorHandling int + +const ( + ContinueOnError ErrorHandling = iota + ExitOnError + PanicOnError +) + +// A FlagSet represents a set of defined flags. The zero value of a FlagSet +// has no name and has ContinueOnError error handling. +type FlagSet struct { + // Usage is the function called when an error occurs while parsing flags. + // The field is a function (not a method) that may be changed to point to + // a custom error handler. + Usage func() + + name string + parsed bool + actual map[string]*Flag + formal map[string]*Flag + envPrefix string // prefix to all env variable names + args []string // arguments after flags + exitOnError bool // does the program exit if there's an error? + errorHandling ErrorHandling + output io.Writer // nil means stderr; use out() accessor +} + +// A Flag represents the state of a flag. +type Flag struct { + Name string // name as it appears on command line + Usage string // help message + Value Value // value as set + DefValue string // default value (as text); for usage message +} + +// sortFlags returns the flags as a slice in lexicographical sorted order. +func sortFlags(flags map[string]*Flag) []*Flag { + list := make(sort.StringSlice, len(flags)) + i := 0 + for _, f := range flags { + list[i] = f.Name + i++ + } + list.Sort() + result := make([]*Flag, len(list)) + for i, name := range list { + result[i] = flags[name] + } + return result +} + +func (f *FlagSet) out() io.Writer { + if f.output == nil { + return os.Stderr + } + return f.output +} + +// SetOutput sets the destination for usage and error messages. +// If output is nil, os.Stderr is used. +func (f *FlagSet) SetOutput(output io.Writer) { + f.output = output +} + +// VisitAll visits the flags in lexicographical order, calling fn for each. +// It visits all flags, even those not set. +func (f *FlagSet) VisitAll(fn func(*Flag)) { + for _, flag := range sortFlags(f.formal) { + fn(flag) + } +} + +// VisitAll visits the command-line flags in lexicographical order, calling +// fn for each. It visits all flags, even those not set. +func VisitAll(fn func(*Flag)) { + CommandLine.VisitAll(fn) +} + +// Visit visits the flags in lexicographical order, calling fn for each. +// It visits only those flags that have been set. +func (f *FlagSet) Visit(fn func(*Flag)) { + for _, flag := range sortFlags(f.actual) { + fn(flag) + } +} + +// Visit visits the command-line flags in lexicographical order, calling fn +// for each. It visits only those flags that have been set. +func Visit(fn func(*Flag)) { + CommandLine.Visit(fn) +} + +// Lookup returns the Flag structure of the named flag, returning nil if none exists. +func (f *FlagSet) Lookup(name string) *Flag { + return f.formal[name] +} + +// Lookup returns the Flag structure of the named command-line flag, +// returning nil if none exists. +func Lookup(name string) *Flag { + return CommandLine.formal[name] +} + +// Set sets the value of the named flag. +func (f *FlagSet) Set(name, value string) error { + flag, ok := f.formal[name] + if !ok { + return fmt.Errorf("no such flag -%v", name) + } + err := flag.Value.Set(value) + if err != nil { + return err + } + if f.actual == nil { + f.actual = make(map[string]*Flag) + } + f.actual[name] = flag + return nil +} + +// Set sets the value of the named command-line flag. +func Set(name, value string) error { + return CommandLine.Set(name, value) +} + +// PrintDefaults prints, to standard error unless configured +// otherwise, the default values of all defined flags in the set. +func (f *FlagSet) PrintDefaults() { + f.VisitAll(func(flag *Flag) { + format := " -%s=%s: %s\n" + if _, ok := flag.Value.(*stringValue); ok { + // put quotes on the value + format = " -%s=%q: %s\n" + } + fmt.Fprintf(f.out(), format, flag.Name, flag.DefValue, flag.Usage) + }) +} + +// PrintDefaults prints to standard error the default values of all defined command-line flags. +func PrintDefaults() { + CommandLine.PrintDefaults() +} + +// defaultUsage is the default function to print a usage message. +func defaultUsage(f *FlagSet) { + if f.name == "" { + fmt.Fprintf(f.out(), "Usage:\n") + } else { + fmt.Fprintf(f.out(), "Usage of %s:\n", f.name) + } + f.PrintDefaults() +} + +// NOTE: Usage is not just defaultUsage(CommandLine) +// because it serves (via godoc flag Usage) as the example +// for how to write your own usage function. + +// Usage prints to standard error a usage message documenting all defined command-line flags. +// The function is a variable that may be changed to point to a custom function. +var Usage = func() { + fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0]) + PrintDefaults() +} + +// NFlag returns the number of flags that have been set. +func (f *FlagSet) NFlag() int { return len(f.actual) } + +// NFlag returns the number of command-line flags that have been set. +func NFlag() int { return len(CommandLine.actual) } + +// Arg returns the i'th argument. Arg(0) is the first remaining argument +// after flags have been processed. +func (f *FlagSet) Arg(i int) string { + if i < 0 || i >= len(f.args) { + return "" + } + return f.args[i] +} + +// Arg returns the i'th command-line argument. Arg(0) is the first remaining argument +// after flags have been processed. +func Arg(i int) string { + return CommandLine.Arg(i) +} + +// NArg is the number of arguments remaining after flags have been processed. +func (f *FlagSet) NArg() int { return len(f.args) } + +// NArg is the number of arguments remaining after flags have been processed. +func NArg() int { return len(CommandLine.args) } + +// Args returns the non-flag arguments. +func (f *FlagSet) Args() []string { return f.args } + +// Args returns the non-flag command-line arguments. +func Args() []string { return CommandLine.args } + +// BoolVar defines a bool flag with specified name, default value, and usage string. +// The argument p points to a bool variable in which to store the value of the flag. +func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) { + f.Var(newBoolValue(value, p), name, usage) +} + +// BoolVar defines a bool flag with specified name, default value, and usage string. +// The argument p points to a bool variable in which to store the value of the flag. +func BoolVar(p *bool, name string, value bool, usage string) { + CommandLine.Var(newBoolValue(value, p), name, usage) +} + +// Bool defines a bool flag with specified name, default value, and usage string. +// The return value is the address of a bool variable that stores the value of the flag. +func (f *FlagSet) Bool(name string, value bool, usage string) *bool { + p := new(bool) + f.BoolVar(p, name, value, usage) + return p +} + +// Bool defines a bool flag with specified name, default value, and usage string. +// The return value is the address of a bool variable that stores the value of the flag. +func Bool(name string, value bool, usage string) *bool { + return CommandLine.Bool(name, value, usage) +} + +// IntVar defines an int flag with specified name, default value, and usage string. +// The argument p points to an int variable in which to store the value of the flag. +func (f *FlagSet) IntVar(p *int, name string, value int, usage string) { + f.Var(newIntValue(value, p), name, usage) +} + +// IntVar defines an int flag with specified name, default value, and usage string. +// The argument p points to an int variable in which to store the value of the flag. +func IntVar(p *int, name string, value int, usage string) { + CommandLine.Var(newIntValue(value, p), name, usage) +} + +// Int defines an int flag with specified name, default value, and usage string. +// The return value is the address of an int variable that stores the value of the flag. +func (f *FlagSet) Int(name string, value int, usage string) *int { + p := new(int) + f.IntVar(p, name, value, usage) + return p +} + +// Int defines an int flag with specified name, default value, and usage string. +// The return value is the address of an int variable that stores the value of the flag. +func Int(name string, value int, usage string) *int { + return CommandLine.Int(name, value, usage) +} + +// Int64Var defines an int64 flag with specified name, default value, and usage string. +// The argument p points to an int64 variable in which to store the value of the flag. +func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) { + f.Var(newInt64Value(value, p), name, usage) +} + +// Int64Var defines an int64 flag with specified name, default value, and usage string. +// The argument p points to an int64 variable in which to store the value of the flag. +func Int64Var(p *int64, name string, value int64, usage string) { + CommandLine.Var(newInt64Value(value, p), name, usage) +} + +// Int64 defines an int64 flag with specified name, default value, and usage string. +// The return value is the address of an int64 variable that stores the value of the flag. +func (f *FlagSet) Int64(name string, value int64, usage string) *int64 { + p := new(int64) + f.Int64Var(p, name, value, usage) + return p +} + +// Int64 defines an int64 flag with specified name, default value, and usage string. +// The return value is the address of an int64 variable that stores the value of the flag. +func Int64(name string, value int64, usage string) *int64 { + return CommandLine.Int64(name, value, usage) +} + +// UintVar defines a uint flag with specified name, default value, and usage string. +// The argument p points to a uint variable in which to store the value of the flag. +func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) { + f.Var(newUintValue(value, p), name, usage) +} + +// UintVar defines a uint flag with specified name, default value, and usage string. +// The argument p points to a uint variable in which to store the value of the flag. +func UintVar(p *uint, name string, value uint, usage string) { + CommandLine.Var(newUintValue(value, p), name, usage) +} + +// Uint defines a uint flag with specified name, default value, and usage string. +// The return value is the address of a uint variable that stores the value of the flag. +func (f *FlagSet) Uint(name string, value uint, usage string) *uint { + p := new(uint) + f.UintVar(p, name, value, usage) + return p +} + +// Uint defines a uint flag with specified name, default value, and usage string. +// The return value is the address of a uint variable that stores the value of the flag. +func Uint(name string, value uint, usage string) *uint { + return CommandLine.Uint(name, value, usage) +} + +// Uint64Var defines a uint64 flag with specified name, default value, and usage string. +// The argument p points to a uint64 variable in which to store the value of the flag. +func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) { + f.Var(newUint64Value(value, p), name, usage) +} + +// Uint64Var defines a uint64 flag with specified name, default value, and usage string. +// The argument p points to a uint64 variable in which to store the value of the flag. +func Uint64Var(p *uint64, name string, value uint64, usage string) { + CommandLine.Var(newUint64Value(value, p), name, usage) +} + +// Uint64 defines a uint64 flag with specified name, default value, and usage string. +// The return value is the address of a uint64 variable that stores the value of the flag. +func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 { + p := new(uint64) + f.Uint64Var(p, name, value, usage) + return p +} + +// Uint64 defines a uint64 flag with specified name, default value, and usage string. +// The return value is the address of a uint64 variable that stores the value of the flag. +func Uint64(name string, value uint64, usage string) *uint64 { + return CommandLine.Uint64(name, value, usage) +} + +// StringVar defines a string flag with specified name, default value, and usage string. +// The argument p points to a string variable in which to store the value of the flag. +func (f *FlagSet) StringVar(p *string, name string, value string, usage string) { + f.Var(newStringValue(value, p), name, usage) +} + +// StringVar defines a string flag with specified name, default value, and usage string. +// The argument p points to a string variable in which to store the value of the flag. +func StringVar(p *string, name string, value string, usage string) { + CommandLine.Var(newStringValue(value, p), name, usage) +} + +// String defines a string flag with specified name, default value, and usage string. +// The return value is the address of a string variable that stores the value of the flag. +func (f *FlagSet) String(name string, value string, usage string) *string { + p := new(string) + f.StringVar(p, name, value, usage) + return p +} + +// String defines a string flag with specified name, default value, and usage string. +// The return value is the address of a string variable that stores the value of the flag. +func String(name string, value string, usage string) *string { + return CommandLine.String(name, value, usage) +} + +// Float64Var defines a float64 flag with specified name, default value, and usage string. +// The argument p points to a float64 variable in which to store the value of the flag. +func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string) { + f.Var(newFloat64Value(value, p), name, usage) +} + +// Float64Var defines a float64 flag with specified name, default value, and usage string. +// The argument p points to a float64 variable in which to store the value of the flag. +func Float64Var(p *float64, name string, value float64, usage string) { + CommandLine.Var(newFloat64Value(value, p), name, usage) +} + +// Float64 defines a float64 flag with specified name, default value, and usage string. +// The return value is the address of a float64 variable that stores the value of the flag. +func (f *FlagSet) Float64(name string, value float64, usage string) *float64 { + p := new(float64) + f.Float64Var(p, name, value, usage) + return p +} + +// Float64 defines a float64 flag with specified name, default value, and usage string. +// The return value is the address of a float64 variable that stores the value of the flag. +func Float64(name string, value float64, usage string) *float64 { + return CommandLine.Float64(name, value, usage) +} + +// DurationVar defines a time.Duration flag with specified name, default value, and usage string. +// The argument p points to a time.Duration variable in which to store the value of the flag. +func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) { + f.Var(newDurationValue(value, p), name, usage) +} + +// DurationVar defines a time.Duration flag with specified name, default value, and usage string. +// The argument p points to a time.Duration variable in which to store the value of the flag. +func DurationVar(p *time.Duration, name string, value time.Duration, usage string) { + CommandLine.Var(newDurationValue(value, p), name, usage) +} + +// Duration defines a time.Duration flag with specified name, default value, and usage string. +// The return value is the address of a time.Duration variable that stores the value of the flag. +func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration { + p := new(time.Duration) + f.DurationVar(p, name, value, usage) + return p +} + +// Duration defines a time.Duration flag with specified name, default value, and usage string. +// The return value is the address of a time.Duration variable that stores the value of the flag. +func Duration(name string, value time.Duration, usage string) *time.Duration { + return CommandLine.Duration(name, value, usage) +} + +// Var defines a flag with the specified name and usage string. The type and +// value of the flag are represented by the first argument, of type Value, which +// typically holds a user-defined implementation of Value. For instance, the +// caller could create a flag that turns a comma-separated string into a slice +// of strings by giving the slice the methods of Value; in particular, Set would +// decompose the comma-separated string into the slice. +func (f *FlagSet) Var(value Value, name string, usage string) { + // Remember the default value as a string; it won't change. + flag := &Flag{name, usage, value, value.String()} + _, alreadythere := f.formal[name] + if alreadythere { + var msg string + if f.name == "" { + msg = fmt.Sprintf("flag redefined: %s", name) + } else { + msg = fmt.Sprintf("%s flag redefined: %s", f.name, name) + } + fmt.Fprintln(f.out(), msg) + panic(msg) // Happens only if flags are declared with identical names + } + if f.formal == nil { + f.formal = make(map[string]*Flag) + } + f.formal[name] = flag +} + +// Var defines a flag with the specified name and usage string. The type and +// value of the flag are represented by the first argument, of type Value, which +// typically holds a user-defined implementation of Value. For instance, the +// caller could create a flag that turns a comma-separated string into a slice +// of strings by giving the slice the methods of Value; in particular, Set would +// decompose the comma-separated string into the slice. +func Var(value Value, name string, usage string) { + CommandLine.Var(value, name, usage) +} + +// failf prints to standard error a formatted error and usage message and +// returns the error. +func (f *FlagSet) failf(format string, a ...interface{}) error { + err := fmt.Errorf(format, a...) + fmt.Fprintln(f.out(), err) + f.usage() + return err +} + +// usage calls the Usage method for the flag set, or the usage function if +// the flag set is CommandLine. +func (f *FlagSet) usage() { + if f == CommandLine { + Usage() + } else if f.Usage == nil { + defaultUsage(f) + } else { + f.Usage() + } +} + +// parseOne parses one flag. It reports whether a flag was seen. +func (f *FlagSet) parseOne() (bool, error) { + if len(f.args) == 0 { + return false, nil + } + s := f.args[0] + if len(s) == 0 || s[0] != '-' || len(s) == 1 { + return false, nil + } + numMinuses := 1 + if s[1] == '-' { + numMinuses++ + if len(s) == 2 { // "--" terminates the flags + f.args = f.args[1:] + return false, nil + } + } + name := s[numMinuses:] + if len(name) == 0 || name[0] == '-' || name[0] == '=' { + return false, f.failf("bad flag syntax: %s", s) + } + + // ignore go test flags + if strings.HasPrefix(name, "test.") { + return false, nil + } + + // it's a flag. does it have an argument? + f.args = f.args[1:] + hasValue := false + value := "" + for i := 1; i < len(name); i++ { // equals cannot be first + if name[i] == '=' { + value = name[i+1:] + hasValue = true + name = name[0:i] + break + } + } + m := f.formal + flag, alreadythere := m[name] // BUG + if !alreadythere { + if name == "help" || name == "h" { // special case for nice help message. + f.usage() + return false, ErrHelp + } + return false, f.failf("flag provided but not defined: -%s", name) + } + if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg + if hasValue { + if err := fv.Set(value); err != nil { + return false, f.failf("invalid boolean value %q for -%s: %v", value, name, err) + } + } else { + fv.Set("true") + } + } else { + // It must have a value, which might be the next argument. + if !hasValue && len(f.args) > 0 { + // value is the next arg + hasValue = true + value, f.args = f.args[0], f.args[1:] + } + if !hasValue { + return false, f.failf("flag needs an argument: -%s", name) + } + if err := flag.Value.Set(value); err != nil { + return false, f.failf("invalid value %q for flag -%s: %v", value, name, err) + } + } + if f.actual == nil { + f.actual = make(map[string]*Flag) + } + f.actual[name] = flag + return true, nil +} + +// Parse parses flag definitions from the argument list, which should not +// include the command name. Must be called after all flags in the FlagSet +// are defined and before flags are accessed by the program. +// The return value will be ErrHelp if -help was set but not defined. +func (f *FlagSet) Parse(arguments []string) error { + f.parsed = true + f.args = arguments + for { + seen, err := f.parseOne() + if seen { + continue + } + if err == nil { + break + } + switch f.errorHandling { + case ContinueOnError: + return err + case ExitOnError: + os.Exit(2) + case PanicOnError: + panic(err) + } + } + + // Parse environment variables + if err := f.ParseEnv(os.Environ()); err != nil { + switch f.errorHandling { + case ContinueOnError: + return err + case ExitOnError: + os.Exit(2) + case PanicOnError: + panic(err) + } + return err + } + + // Parse configuration from file + var cFile string + if cf := f.formal[DefaultConfigFlagname]; cf != nil { + cFile = cf.Value.String() + } + if cf := f.actual[DefaultConfigFlagname]; cf != nil { + cFile = cf.Value.String() + } + if cFile != "" { + if err := f.ParseFile(cFile); err != nil { + switch f.errorHandling { + case ContinueOnError: + return err + case ExitOnError: + os.Exit(2) + case PanicOnError: + panic(err) + } + return err + } + } + + return nil +} + +// ParseEnv parses flags from environment variables. +// Flags already set will be ignored. +func (f *FlagSet) ParseEnv(environ []string) error { + + m := f.formal + + env := make(map[string]string) + for _, s := range environ { + i := strings.Index(s, "=") + if i < 1 { + continue + } + env[s[0:i]] = s[i+1 : len(s)] + } + + for _, flag := range m { + name := flag.Name + _, set := f.actual[name] + if set { + continue + } + + flag, alreadythere := m[name] + if !alreadythere { + if name == "help" || name == "h" { // special case for nice help message. + f.usage() + return ErrHelp + } + return f.failf("environment variable provided but not defined: %s", name) + } + + envKey := strings.ToUpper(flag.Name) + if f.envPrefix != "" { + envKey = f.envPrefix + "_" + envKey + } + envKey = strings.Replace(envKey, "-", "_", -1) + + value, isSet := env[envKey] + if !isSet { + continue + } + + hasValue := false + if len(value) > 0 { + hasValue = true + } + + if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg + if hasValue { + if err := fv.Set(value); err != nil { + return f.failf("invalid boolean value %q for environment variable %s: %v", value, name, err) + } + } else { + // flag without value is regarded a bool + fv.Set("true") + } + } else { + if err := flag.Value.Set(value); err != nil { + return f.failf("invalid value %q for environment variable %s: %v", value, name, err) + } + } + + // update f.actual + if f.actual == nil { + f.actual = make(map[string]*Flag) + } + f.actual[name] = flag + + } + return nil +} + +// ParseFile parses flags from the file in path. +// Same format as commandline argumens, newlines and lines beginning with a +// "#" charater are ignored. Flags already set will be ignored. +func (f *FlagSet) ParseFile(path string) error { + + // Extract arguments from file + fp, err := os.Open(path) + if err != nil { + return err + } + defer fp.Close() + + scanner := bufio.NewScanner(fp) + for scanner.Scan() { + line := scanner.Text() + + // Ignore empty lines + if len(line) == 0 { + continue + } + + // Ignore comments + if line[:1] == "#" { + continue + } + + // Match `key=value` and `key value` + var name, value string + hasValue := false + for i, v := range line { + if v == '=' || v == ' ' { + hasValue = true + name, value = line[:i], line[i+1:] + break + } + } + + if hasValue == false { + name = line + } + + // Ignore flag when already set; arguments have precedence over file + if f.actual[name] != nil { + continue + } + + m := f.formal + flag, alreadythere := m[name] + if !alreadythere { + if name == "help" || name == "h" { // special case for nice help message. + f.usage() + return ErrHelp + } + return f.failf("configuration variable provided but not defined: %s", name) + } + + if fv, ok := flag.Value.(boolFlag); ok && fv.IsBoolFlag() { // special case: doesn't need an arg + if hasValue { + if err := fv.Set(value); err != nil { + return f.failf("invalid boolean value %q for configuration variable %s: %v", value, name, err) + } + } else { + // flag without value is regarded a bool + fv.Set("true") + } + } else { + if err := flag.Value.Set(value); err != nil { + return f.failf("invalid value %q for configuration variable %s: %v", value, name, err) + } + } + + // update f.actual + if f.actual == nil { + f.actual = make(map[string]*Flag) + } + f.actual[name] = flag + } + + if err := scanner.Err(); err != nil { + return err + } + + return nil +} + +// Parsed reports whether f.Parse has been called. +func (f *FlagSet) Parsed() bool { + return f.parsed +} + +// Parse parses the command-line flags from os.Args[1:]. Must be called +// after all flags are defined and before flags are accessed by the program. +func Parse() { + // Ignore errors; CommandLine is set for ExitOnError. + CommandLine.Parse(os.Args[1:]) +} + +// Parsed returns true if the command-line flags have been parsed. +func Parsed() bool { + return CommandLine.Parsed() +} + +// CommandLine is the default set of command-line flags, parsed from os.Args. +// The top-level functions such as BoolVar, Arg, and on are wrappers for the +// methods of CommandLine. +var CommandLine = NewFlagSet(os.Args[0], ExitOnError) + +// NewFlagSet returns a new, empty flag set with the specified name and +// error handling property. +func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet { + f := &FlagSet{ + name: name, + errorHandling: errorHandling, + } + return f +} + +// NewFlagSetWithEnvPrefix returns a new empty flag set with the specified name, +// environment variable prefix, and error handling property. +func NewFlagSetWithEnvPrefix(name string, prefix string, errorHandling ErrorHandling) *FlagSet { + f := NewFlagSet(name, errorHandling) + f.envPrefix = prefix + return f +} + +// Init sets the name, environment name prefix, and error handling property +// for a flag set. +// By default, the zero FlagSet uses an empty name, EnvironmentPrefix, and the +// ContinueOnError error handling policy. +func (f *FlagSet) Init(name string, errorHandling ErrorHandling) { + f.name = name + f.envPrefix = EnvironmentPrefix + f.errorHandling = errorHandling +} -- cgit v1.2.3