cmd/geth: add --config file flag (#13875)

* p2p/discover, p2p/discv5: add marshaling methods to Node

* p2p/netutil: make Netlist decodable from TOML

* common/math: encode nil HexOrDecimal256 as 0x0

* cmd/geth: add --config file flag

* cmd/geth: add missing license header

* eth: prettify Config again, fix tests

* eth: use gasprice.Config instead of duplicating its fields

* eth/gasprice: hide nil default from dumpconfig output

* cmd/geth: hide genesis block in dumpconfig output

* node: make tests compile

* console: fix tests

* cmd/geth: make TOML keys look exactly like Go struct fields

* p2p: use discovery by default

This makes the zero Config slightly more useful. It also fixes package
node tests because Node detects reuse of the datadir through the
NodeDatabase.

* cmd/geth: make ethstats URL settable through config file

* cmd/faucet: fix configuration

* cmd/geth: dedup attach tests

* eth: add comment for DefaultConfig

* eth: pass downloader.SyncMode in Config

This removes the FastSync, LightSync flags in favour of a more
general SyncMode flag.

* cmd/utils: remove jitvm flags

* cmd/utils: make mutually exclusive flag error prettier

It now reads:

   Fatal: flags --dev, --testnet can't be used at the same time

* p2p: fix typo

* node: add DefaultConfig, use it for geth

* mobile: add missing NoDiscovery option

* cmd/utils: drop MakeNode

This exposed a couple of places that needed to be updated to use
node.DefaultConfig.

* node: fix typo

* eth: make fast sync the default mode

* cmd/utils: remove IPCApiFlag (unused)

* node: remove default IPC path

Set it in the frontends instead.

* cmd/geth: add --syncmode

* cmd/utils: make --ipcdisable and --ipcpath mutually exclusive

* cmd/utils: don't enable WS, HTTP when setting addr

* cmd/utils: fix --identity

1 files changed, 86 insertions, 0 deletions

diff --git a/vendor/github.com/naoina/toml/config.go b/vendor/github.com/naoina/toml/config.go
new file mode 100644
index 000000000..06bb9493b
--- /dev/null
+++ b/vendor/github.com/naoina/toml/config.go
@@ -0,0 +1,86 @@
+package toml
+
+import (
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+
+	stringutil "github.com/naoina/go-stringutil"
+	"github.com/naoina/toml/ast"
+)
+
+// Config contains options for encoding and decoding.
+type Config struct {
+	// NormFieldName is used to match TOML keys to struct fields. The function runs for
+	// both input keys and struct field names and should return a string that makes the
+	// two match. You must set this field to use the decoder.
+	//
+	// Example: The function in the default config removes _ and lowercases all keys. This
+	// allows a key called 'api_key' to match the struct field 'APIKey' because both are
+	// normalized to 'apikey'.
+	//
+	// Note that NormFieldName is not used for fields which define a TOML
+	// key through the struct tag.
+	NormFieldName func(typ reflect.Type, keyOrField string) string
+
+	// FieldToKey determines the TOML key of a struct field when encoding.
+	// You must set this field to use the encoder.
+	//
+	// Note that FieldToKey is not used for fields which define a TOML
+	// key through the struct tag.
+	FieldToKey func(typ reflect.Type, field string) string
+
+	// MissingField, if non-nil, is called when the decoder encounters a key for which no
+	// matching struct field exists. The default behavior is to return an error.
+	MissingField func(typ reflect.Type, key string) error
+}
+
+// DefaultConfig contains the default options for encoding and decoding.
+// Snake case (i.e. 'foo_bar') is used for key names.
+var DefaultConfig = Config{
+	NormFieldName: defaultNormFieldName,
+	FieldToKey:    snakeCase,
+}
+
+func defaultNormFieldName(typ reflect.Type, s string) string {
+	return strings.Replace(strings.ToLower(s), "_", "", -1)
+}
+
+func snakeCase(typ reflect.Type, s string) string {
+	return stringutil.ToSnakeCase(s)
+}
+
+func defaultMissingField(typ reflect.Type, key string) error {
+	return fmt.Errorf("field corresponding to `%s' is not defined in %v", key, typ)
+}
+
+// NewEncoder returns a new Encoder that writes to w.
+// It is shorthand for DefaultConfig.NewEncoder(w).
+func NewEncoder(w io.Writer) *Encoder {
+	return DefaultConfig.NewEncoder(w)
+}
+
+// Marshal returns the TOML encoding of v.
+// It is shorthand for DefaultConfig.Marshal(v).
+func Marshal(v interface{}) ([]byte, error) {
+	return DefaultConfig.Marshal(v)
+}
+
+// Unmarshal parses the TOML data and stores the result in the value pointed to by v.
+// It is shorthand for DefaultConfig.Unmarshal(data, v).
+func Unmarshal(data []byte, v interface{}) error {
+	return DefaultConfig.Unmarshal(data, v)
+}
+
+// UnmarshalTable applies the contents of an ast.Table to the value pointed at by v.
+// It is shorthand for DefaultConfig.UnmarshalTable(t, v).
+func UnmarshalTable(t *ast.Table, v interface{}) error {
+	return DefaultConfig.UnmarshalTable(t, v)
+}
+
+// NewDecoder returns a new Decoder that reads from r.
+// It is shorthand for DefaultConfig.NewDecoder(r).
+func NewDecoder(r io.Reader) *Decoder {
+	return DefaultConfig.NewDecoder(r)
+}