Documentation
¶
Overview ¶
Package gosym implements access to the Go symbol and line number tables embedded in Go binaries generated by the gc compilers.
See https://golang.org/s/go12symtab
This is a fork of the Go standard library's debug/gosym package, with some stuff added for use by Shotizam.
Index ¶
- type DecodingError
- type Func
- type LineTable
- type Obj
- type Sym
- type Table
- func (t *Table) LineToPC(file string, line int) (pc uint64, fn *Func, err error)
- func (t *Table) LookupFunc(name string) *Func
- func (t *Table) LookupSym(name string) *Sym
- func (t *Table) PCToFunc(pc uint64) *Func
- func (t *Table) PCToLine(pc uint64) (file string, line int, fn *Func)
- func (t *Table) PtrSize() int
- func (t *Table) SymByAddr(addr uint64) *Sym
- type UnknownFileError
- type UnknownLineError
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type DecodingError ¶
type DecodingError struct {
// contains filtered or unexported fields
}
DecodingError represents an error during the decoding of the symbol table.
func (*DecodingError) Error ¶
func (e *DecodingError) Error() string
type Func ¶
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
OffPCSP uint32 // pcsp table (offset from pcvalue table)
OffPCFile uint32 // pcfile table (offset from pcvalue table)
OffPCLn uint32 // pcln table (offset from pcvalue table)
NumPCData int // number of entries in pcdata list
NumFuncData int // number of entries in funcdata list
// contains filtered or unexported fields
}
A Func collects information about a single function.
func (*Func) ForeachTableEntry ¶
func (*Func) TableSizePCData ¶
tab is 0-based table number.
func (*Func) TableSizePCFile ¶
func (*Func) TableSizePCLn ¶
func (*Func) TableSizePCSP ¶
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.
func NewLineTable ¶
NewLineTable returns a new PC/line table corresponding to the encoded data. Text must be the start address of the corresponding text segment.
type Obj ¶
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
}
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 Sym ¶
type Sym struct {
Value uint64
Type byte
Name string
GoType uint64
// If this symbol is a function symbol, the corresponding Func
Func *Func
// contains filtered or unexported fields
}
A Sym represents a single symbol table entry.
func (*Sym) PackageName ¶
PackageName returns the package part of the symbol name, or the empty string if there is none.
func (*Sym) ReceiverName ¶
ReceiverName returns the receiver type name of this symbol, or the empty string if there is none. A receiver name is only detected in the case that s.Name is fully-specified with a package name.
type Table ¶
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
}
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.
func NewTable ¶
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 ¶
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 ¶
LookupFunc returns the text, data, or bss symbol with the given name, or nil if no such symbol is found.
func (*Table) LookupSym ¶
LookupSym returns the text, data, or bss symbol with the given name, or nil if no such symbol is found.
func (*Table) PCToFunc ¶
PCToFunc returns the function containing the program counter pc, or nil if there is no such function.
type UnknownFileError ¶
type UnknownFileError string
UnknownFileError represents a failure to find the specific file in the symbol table.
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.
func (*UnknownLineError) Error ¶
func (e *UnknownLineError) Error() string
Source Files