bootcommand

Documentation

Index

• Constants
• func GenerateExpressionSequence(command string) (expressionSequence, error)
• func NewPCXTDriver(send SendCodeFunc, chunkSize int) *pcXTDriver
• func NewVNCDriver(c VNCKeyEvent) *vncDriver
• func Parse(filename string, b []byte, opts ...Option) (interface{}, error)
• func ParseFile(filename string, opts ...Option) (i interface{}, err error)
• func ParseReader(filename string, r io.Reader, opts ...Option) (interface{}, error)
• type BCDriver
• type BootConfig
  • func (c *BootConfig) FlatBootCommand() string
  • func (c *BootConfig) Prepare(ctx *interpolate.Context) (errs []error)
• type Cloner
• type KeyAction
  • func (k KeyAction) String() string
• type Option
  • func AllowInvalidUTF8(b bool) Option
  • func Debug(b bool) Option
  • func Entrypoint(ruleName string) Option
  • func GlobalStore(key string, value interface{}) Option
  • func InitState(key string, value interface{}) Option
  • func MaxExpressions(maxExprCnt uint64) Option
  • func Memoize(b bool) Option
  • func Recover(b bool) Option
  • func Statistics(stats *Stats, choiceNoMatch string) Option
• type SendCodeFunc
• type Stats
• type VNCConfig
  • func (c *VNCConfig) Prepare(ctx *interpolate.Context) (errs []error)
• type VNCKeyEvent

Constants

const KeyLeftShift uint32 = 0xFFE1

Functions

func GenerateExpressionSequence

func GenerateExpressionSequence(command string) (expressionSequence, error)

GenerateExpressionSequence generates a sequence of expressions from the given command. This is the primary entry point to the boot command parser.

func NewPCXTDriver

func NewPCXTDriver(send SendCodeFunc, chunkSize int) *pcXTDriver

NewPCXTDriver creates a new boot command driver for VMs that expect PC-XT keyboard codes. `send` should send its argument to the VM. `chunkSize` should be the maximum number of keyboard codes to send to `send` at one time.

func NewVNCDriver

func NewVNCDriver(c VNCKeyEvent) *vncDriver

func Parse

func Parse(filename string, b []byte, opts ...Option) (interface{}, error)

Parse parses the data from b using filename as information in the error messages.

func ParseFile

func ParseFile(filename string, opts ...Option) (i interface{}, err error)

ParseFile parses the file identified by filename.

func ParseReader

func ParseReader(filename string, r io.Reader, opts ...Option) (interface{}, error)

ParseReader parses the data from r using filename as information in the error messages.

Types

type BCDriver

type BCDriver interface {
	SendKey(key rune, action KeyAction) error
	SendSpecial(special string, action KeyAction) error
	// Flush will be called when we want to send scancodes to the VM.
	Flush() error
}

BCDriver is our access to the VM we want to type boot commands to

type BootConfig

type BootConfig struct {
	RawBootWait string   `mapstructure:"boot_wait"`
	BootCommand []string `mapstructure:"boot_command"`

	BootWait time.Duration ``
}

func (*BootConfig) FlatBootCommand

func (c *BootConfig) FlatBootCommand() string

func (*BootConfig) Prepare

func (c *BootConfig) Prepare(ctx *interpolate.Context) (errs []error)

type Cloner

type Cloner interface {
	Clone() interface{}
}

Cloner is implemented by any value that has a Clone method, which returns a copy of the value. This is mainly used for types which are not passed by value (e.g map, slice, chan) or structs that contain such types.

This is used in conjunction with the global state feature to create proper copies of the state to allow the parser to properly restore the state in the case of backtracking.

type KeyAction

type KeyAction int

KeysAction represents what we want to do with a key press. It can take 3 states. We either want to: * press the key once * press and hold * press and release

const (
	KeyOn KeyAction = 1 << iota
	KeyOff
	KeyPress
)

func (KeyAction) String

func (k KeyAction) String() string

type Option

type Option func(*parser) Option

Option is a function that can set an option on the parser. It returns the previous setting as an Option.

func AllowInvalidUTF8

func AllowInvalidUTF8(b bool) Option

AllowInvalidUTF8 creates an Option to allow invalid UTF-8 bytes. Every invalid UTF-8 byte is treated as a utf8.RuneError (U+FFFD) by character class matchers and is matched by the any matcher. The returned matched value, c.text and c.offset are NOT affected.

The default is false.

func Debug

func Debug(b bool) Option

Debug creates an Option to set the debug flag to b. When set to true, debugging information is printed to stdout while parsing.

The default is false.

func Entrypoint

func Entrypoint(ruleName string) Option

Entrypoint creates an Option to set the rule name to use as entrypoint. The rule name must have been specified in the -alternate-entrypoints if generating the parser with the -optimize-grammar flag, otherwise it may have been optimized out. Passing an empty string sets the entrypoint to the first rule in the grammar.

The default is to start parsing at the first rule in the grammar.

func GlobalStore

func GlobalStore(key string, value interface{}) Option

GlobalStore creates an Option to set a key to a certain value in the globalStore.

func InitState

func InitState(key string, value interface{}) Option

InitState creates an Option to set a key to a certain value in the global "state" store.

func MaxExpressions

func MaxExpressions(maxExprCnt uint64) Option

MaxExpressions creates an Option to stop parsing after the provided number of expressions have been parsed, if the value is 0 then the parser will parse for as many steps as needed (possibly an infinite number).

The default for maxExprCnt is 0.

func Memoize

func Memoize(b bool) Option

Memoize creates an Option to set the memoize flag to b. When set to true, the parser will cache all results so each expression is evaluated only once. This guarantees linear parsing time even for pathological cases, at the expense of more memory and slower times for typical cases.

The default is false.

func Recover

func Recover(b bool) Option

Recover creates an Option to set the recover flag to b. When set to true, this causes the parser to recover from panics and convert it to an error. Setting it to false can be useful while debugging to access the full stack trace.

The default is true.

func Statistics

func Statistics(stats *Stats, choiceNoMatch string) Option

Statistics adds a user provided Stats struct to the parser to allow the user to process the results after the parsing has finished. Also the key for the "no match" counter is set.

Example usage:

input := "input"
stats := Stats{}
_, err := Parse("input-file", []byte(input), Statistics(&stats, "no match"))
if err != nil {
    log.Panicln(err)
}
b, err := json.MarshalIndent(stats.ChoiceAltCnt, "", "  ")
if err != nil {
    log.Panicln(err)
}
fmt.Println(string(b))

type SendCodeFunc

type SendCodeFunc func([]string) error

SendCodeFunc will be called to send codes to the VM

type Stats

type Stats struct {
	// ExprCnt counts the number of expressions processed during parsing
	// This value is compared to the maximum number of expressions allowed
	// (set by the MaxExpressions option).
	ExprCnt uint64

	// ChoiceAltCnt is used to count for each ordered choice expression,
	// which alternative is used how may times.
	// These numbers allow to optimize the order of the ordered choice expression
	// to increase the performance of the parser
	//
	// The outer key of ChoiceAltCnt is composed of the name of the rule as well
	// as the line and the column of the ordered choice.
	// The inner key of ChoiceAltCnt is the number (one-based) of the matching alternative.
	// For each alternative the number of matches are counted. If an ordered choice does not
	// match, a special counter is incremented. The name of this counter is set with
	// the parser option Statistics.
	// For an alternative to be included in ChoiceAltCnt, it has to match at least once.
	ChoiceAltCnt map[string]map[string]int
}

Stats stores some statistics, gathered during parsing

type VNCConfig

type VNCConfig struct {
	BootConfig `mapstructure:",squash"`
	DisableVNC bool `mapstructure:"disable_vnc"`
}

func (*VNCConfig) Prepare

func (c *VNCConfig) Prepare(ctx *interpolate.Context) (errs []error)

type VNCKeyEvent

type VNCKeyEvent interface {
	KeyEvent(uint32, bool) error
}