Package gosym
Overview
Package gosym implements access to the Go symbol and line number tables embedded in Go binaries generated by the gc compilers.
Index
Package files
pclntab.go symtab.go
type DecodingError
DecodingError represents an error during the decoding of the symbol table.
type DecodingError struct {
// contains filtered or unexported fields
}
func (*DecodingError) Error
func (e *DecodingError) Error() string
type Func
A Func collects information about a single function.
type Func struct {
Entry uint64
*Sym
End uint64
Params []*Sym // nil for Go 1.3 and later binaries
Locals []*Sym // nil for Go 1.3 and later binaries
FrameSize int
LineTable *LineTable
Obj *Obj
}
type LineTable
A LineTable is a data structure mapping program counters to line numbers.
In Go 1.1 and earlier, each function (represented by a Func) had its own LineTable, and the line number corresponded to a numbering of all source lines in the program, across all files. That absolute line number would then have to be converted separately to a file name and line number within the file.
In Go 1.2, the format of the data changed so that there is a single LineTable for the entire program, shared by all Funcs, and there are no absolute line numbers, just line numbers within specific files.
For the most part, LineTable's methods should be treated as an internal detail of the package; callers should use the methods on Table instead.
type LineTable struct {
Data []byte
PC uint64
Line int
// contains filtered or unexported fields
}
func NewLineTable
func NewLineTable(data []byte, text uint64) *LineTable
NewLineTable returns a new PC/line table corresponding to the encoded data. Text must be the start address of the corresponding text segment.
func (*LineTable) LineToPC
func (t *LineTable) LineToPC(line int, maxpc uint64) uint64
LineToPC returns the program counter for the given line number, considering only program counters before maxpc.
Deprecated: Use Table's LineToPC method instead.
func (*LineTable) PCToLine
func (t *LineTable) PCToLine(pc uint64) int
PCToLine returns the line number for the given program counter.
Deprecated: Use Table's PCToLine method instead.
type Obj
An Obj represents a collection of functions in a symbol table.
The exact method of division of a binary into separate Objs is an internal detail of the symbol table format.
In early versions of Go each source file became a different Obj.
In Go 1 and Go 1.1, each package produced one Obj for all Go sources and one Obj per C source file.
In Go 1.2, there is a single Obj for the entire program.
type Obj struct {
// Funcs is a list of functions in the Obj.
Funcs []Func
// In Go 1.1 and earlier, Paths is a list of symbols corresponding
// to the source file names that produced the Obj.
// In Go 1.2, Paths is nil.
// Use the keys of Table.Files to obtain a list of source files.
Paths []Sym // meta
}
type Sym
A Sym represents a single symbol table entry.
type Sym struct {
Value uint64
Type byte
Name string
GoType uint64
// If this symbol is a function symbol, the corresponding Func
Func *Func
}
func (*Sym) BaseName
func (s *Sym) BaseName() string
BaseName returns the symbol name without the package or receiver name.
func (*Sym) PackageName
func (s *Sym) PackageName() string
PackageName returns the package part of the symbol name, or the empty string if there is none.
func (*Sym) ReceiverName
func (s *Sym) ReceiverName() string
ReceiverName returns the receiver type name of this symbol, or the empty string if there is none.
func (*Sym) Static
func (s *Sym) Static() bool
Static reports whether this symbol is static (not visible outside its file).
type Table
Table represents a Go symbol table. It stores all of the symbols decoded from the program and provides methods to translate between symbols, names, and addresses.
type Table struct {
Syms []Sym // nil for Go 1.3 and later binaries
Funcs []Func
Files map[string]*Obj // for Go 1.2 and later all files map to one Obj
Objs []Obj // for Go 1.2 and later only one Obj in slice
// contains filtered or unexported fields
}
func NewTable
func NewTable(symtab []byte, pcln *LineTable) (*Table, error)
NewTable decodes the Go symbol table (the ".gosymtab" section in ELF), returning an in-memory representation. Starting with Go 1.3, the Go symbol table no longer includes symbol data.
func (*Table) LineToPC
func (t *Table) LineToPC(file string, line int) (pc uint64, fn *Func, err error)
LineToPC looks up the first program counter on the given line in the named file. It returns UnknownPathError or UnknownLineError if there is an error looking up this line.
func (*Table) LookupFunc
func (t *Table) LookupFunc(name string) *Func
LookupFunc returns the text, data, or bss symbol with the given name, or nil if no such symbol is found.
func (*Table) LookupSym
func (t *Table) LookupSym(name string) *Sym
LookupSym returns the text, data, or bss symbol with the given name, or nil if no such symbol is found.
func (*Table) PCToFunc
func (t *Table) PCToFunc(pc uint64) *Func
PCToFunc returns the function containing the program counter pc, or nil if there is no such function.
func (*Table) PCToLine
func (t *Table) PCToLine(pc uint64) (file string, line int, fn *Func)
PCToLine looks up line number information for a program counter. If there is no information, it returns fn == nil.
func (*Table) SymByAddr
func (t *Table) SymByAddr(addr uint64) *Sym
SymByAddr returns the text, data, or bss symbol starting at the given address.
type UnknownFileError
UnknownFileError represents a failure to find the specific file in the symbol table.
type UnknownFileError string
func (UnknownFileError) Error
func (e UnknownFileError) Error() string
type UnknownLineError
UnknownLineError represents a failure to map a line to a program counter, either because the line is beyond the bounds of the file or because there is no code on the given line.
type UnknownLineError struct {
File string
Line int
}
func (*UnknownLineError) Error
func (e *UnknownLineError) Error() string
© Google, Inc.
Licensed under the Creative Commons Attribution License 3.0.
http://golang.org/pkg/debug/gosym/