plugin

Documentation

Overview

Package plugin defines the plugin implementations that the main pprof driver requires.

Index

• type Fetcher
• type FlagSet
• type Frame
• type Inst
• type ObjFile
• type ObjTool
  • func NoObjTool() ObjTool
• type Sym
• type Symbolizer
• type UI
  • func StandardUI() UI

Types

type Fetcher

type Fetcher func(src string, timeout time.Duration, ui UI) (*profile.Profile, error)

A Fetcher reads and returns the profile named by src. It gives up after the given timeout, unless src contains a timeout override (as defined by the implementation). It can print messages to ui.

type FlagSet

type FlagSet interface {
	// Bool, Int, Float64, and String define new flags,
	// like the functions of the same name in package flag.
	Bool(name string, def bool, usage string) *bool
	Int(name string, def int, usage string) *int
	Float64(name string, def float64, usage string) *float64
	String(name string, def string, usage string) *string

	// ExtraUsage returns any additional text that should be
	// printed after the standard usage message.
	// The typical use of ExtraUsage is to show any custom flags
	// defined by the specific pprof plugins being used.
	ExtraUsage() string

	// Parse initializes the flags with their values for this run
	// and returns the non-flag command line arguments.
	// If an unknown flag is encountered or there are no arguments,
	// Parse should call usage and return nil.
	Parse(usage func()) []string
}

A FlagSet creates and parses command-line flags. It is similar to the standard flag.FlagSet.

type Frame

type Frame struct {
	Func string // name of function
	File string // source file name
	Line int    // line in file
}

A Frame describes a single line in a source file.

type Inst

type Inst struct {
	Addr uint64 // virtual address of instruction
	Text string // instruction text
	File string // source file
	Line int    // source line
}

An Inst is a single instruction in an assembly listing.

type ObjFile

type ObjFile interface {
	// Name returns the underlyinf file name, if available
	Name() string

	// Base returns the base address to use when looking up symbols in the file.
	Base() uint64

	// BuildID returns the GNU build ID of the file, or an empty string.
	BuildID() string

	// SourceLine reports the source line information for a given
	// address in the file. Due to inlining, the source line information
	// is in general a list of positions representing a call stack,
	// with the leaf function first.
	SourceLine(addr uint64) ([]Frame, error)

	// Symbols returns a list of symbols in the object file.
	// If r is not nil, Symbols restricts the list to symbols
	// with names matching the regular expression.
	// If addr is not zero, Symbols restricts the list to symbols
	// containing that address.
	Symbols(r *regexp.Regexp, addr uint64) ([]*Sym, error)

	// Close closes the file, releasing associated resources.
	Close() error
}

An ObjFile is a single object file: a shared library or executable.

type ObjTool

type ObjTool interface {
	// Open opens the named object file.
	// If the object is a shared library, start is the address where
	// it is mapped into memory in the address space being inspected.
	Open(file string, start uint64) (ObjFile, error)

	// Demangle translates a batch of symbol names from mangled
	// form to human-readable form.
	Demangle(names []string) (map[string]string, error)

	// Disasm disassembles the named object file, starting at
	// the start address and stopping at (before) the end address.
	Disasm(file string, start, end uint64) ([]Inst, error)

	// SetConfig configures the tool.
	// The implementation defines the meaning of the string
	// and can ignore it entirely.
	SetConfig(config string)
}

An ObjTool inspects shared libraries and executable files.

func NoObjTool

func NoObjTool() ObjTool

NoObjTool returns a trivial implementation of the ObjTool interface. Open returns an error indicating that the requested file does not exist. Demangle returns an empty map and a nil error. Disasm returns an error. SetConfig is a no-op.

type Sym

type Sym struct {
	Name  []string // names of symbol (many if symbol was dedup'ed)
	File  string   // object file containing symbol
	Start uint64   // start virtual address
	End   uint64   // virtual address of last byte in sym (Start+size-1)
}

A Sym describes a single symbol in an object file.

type Symbolizer

type Symbolizer func(mode, src string, prof *profile.Profile, obj ObjTool, ui UI) error

A Symbolizer annotates a profile with symbol information. The profile was fetch from src. The meaning of mode is defined by the implementation.

type UI

type UI interface {
	// Read returns a line of text (a command) read from the user.
	ReadLine() (string, error)

	// Print shows a message to the user.
	// It formats the text as fmt.Print would and adds a final \n if not already present.
	// For line-based UI, Print writes to standard error.
	// (Standard output is reserved for report data.)
	Print(...interface{})

	// PrintErr shows an error message to the user.
	// It formats the text as fmt.Print would and adds a final \n if not already present.
	// For line-based UI, PrintErr writes to standard error.
	PrintErr(...interface{})

	// IsTerminal returns whether the UI is known to be tied to an
	// interactive terminal (as opposed to being redirected to a file).
	IsTerminal() bool

	// SetAutoComplete instructs the UI to call complete(cmd) to obtain
	// the auto-completion of cmd, if the UI supports auto-completion at all.
	SetAutoComplete(complete func(string) string)
}

A UI manages user interactions.

func StandardUI

func StandardUI() UI

StandardUI returns a UI that reads from standard input, prints messages to standard output, prints errors to standard error, and doesn't use auto-completion.