From: Pietro Gagliardi Date: Thu, 10 Jul 2014 19:44:40 +0000 (-0700) Subject: debug/elf: add (*File).DynamicSymbols, ErrNoSymbols, and tests for (*File).Symbols... X-Git-Tag: go1.4beta1~1114 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=f5b600f70cbe1e504a7623a7e0636535c49ea6c8;p=gostls13.git debug/elf: add (*File).DynamicSymbols, ErrNoSymbols, and tests for (*File).Symbols and (*File).DynamicSymbols, and formalize symbol order. Added a complement to (*File).Symbols for the dynamic symbol table. Would be useful, for instance, if seraching for certain shared objects compatible with certain libraries (for instance, LADSPA requires an exported symbol "ladspa_descriptor"). Added a variable ErrNoSymbols that canonicalizes a return from (*File).Symbols and (*File).DyanmicSymbols if the file has no symbols. Added tests for both (*File).Symbols and (*File).DynamicSymbols; there was never a test for (*File).Symbols at all. A small C program using libelf, included in the test data, was used to produce the golden symbols to compare against. As part of the requirements for testing, (*File).Symbols and (*File).DynamicSymbols now document the order in which the symbol tables are returned (in the order the symbols appear in the file). All tests currently pass. LGTM=iant R=golang-codereviews, iant CC=golang-codereviews https://golang.org/cl/107530043 --- diff --git a/src/pkg/debug/elf/file.go b/src/pkg/debug/elf/file.go index 423932fe0f..7be9deaa5f 100644 --- a/src/pkg/debug/elf/file.go +++ b/src/pkg/debug/elf/file.go @@ -405,10 +405,14 @@ func (f *File) getSymbols(typ SectionType) ([]Symbol, []byte, error) { return nil, nil, errors.New("not implemented") } +// ErrNoSymbols is returned by File.Symbols and File.DynamicSymbols +// if there is no such section in the File. +var ErrNoSymbols = errors.New("no symbol section") + func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) { symtabSection := f.SectionByType(typ) if symtabSection == nil { - return nil, nil, errors.New("no symbol section") + return nil, nil, ErrNoSymbols } data, err := symtabSection.Data() @@ -451,7 +455,7 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) { func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) { symtabSection := f.SectionByType(typ) if symtabSection == nil { - return nil, nil, errors.New("no symbol section") + return nil, nil, ErrNoSymbols } data, err := symtabSection.Data() @@ -698,7 +702,8 @@ func (f *File) DWARF() (*dwarf.Data, error) { return d, nil } -// Symbols returns the symbol table for f. +// Symbols returns the symbol table for f. The symbols will be listed in the order +// they appear in f. // // For compatibility with Go 1.0, Symbols omits the null symbol at index 0. // After retrieving the symbols as symtab, an externally supplied index x @@ -708,6 +713,17 @@ func (f *File) Symbols() ([]Symbol, error) { return sym, err } +// DynamicSymbols returns the dynamic symbol table for f. The symbols +// will be listed in the order they appear in f. +// +// For compatibility with Symbols, DynamicSymbols omits the null symbol at index 0. +// After retrieving the symbols as symtab, an externally supplied index x +// corresponds to symtab[x-1], not symtab[x]. +func (f *File) DynamicSymbols() ([]Symbol, error) { + sym, _, err := f.getSymbols(SHT_DYNSYM) + return sym, err +} + type ImportedSymbol struct { Name string Version string diff --git a/src/pkg/debug/elf/symbols_test.go b/src/pkg/debug/elf/symbols_test.go new file mode 100644 index 0000000000..1b79520e3c --- /dev/null +++ b/src/pkg/debug/elf/symbols_test.go @@ -0,0 +1,834 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package elf + +import ( + "io" + "path" + "reflect" + "testing" +) + +// TODO: remove duplicate code +func TestSymbols(t *testing.T) { + do := func(file string, ts []Symbol, getfunc func(*File) ([]Symbol, error)) { + var f *File + var err error + if path.Ext(file) == ".gz" { + var r io.ReaderAt + if r, err = decompress(file); err == nil { + f, err = NewFile(r) + } + } else { + f, err = Open(file) + } + if err != nil { + t.Errorf("TestSymbols: cannot open file %s: %v", file, err) + return + } + defer f.Close() + fs, err := getfunc(f) + if err != nil && err != ErrNoSymbols { + t.Error(err) + return + } else if err == ErrNoSymbols { + fs = []Symbol{} + } + if !reflect.DeepEqual(ts, fs) { + t.Errorf("%s: Symbols = %v, want %v", file, ts, fs) + } + } + for file, ts := range symbolsGolden { + do(file, ts, (*File).Symbols) + } + for file, ts := range dynamicSymbolsGolden { + do(file, ts, (*File).DynamicSymbols) + } +} + +// golden symbol table data generated by testdata/getgoldsym.c + +var symbolsGolden = map[string][]Symbol{ + "testdata/gcc-amd64-linux-exec": { + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1, + Value: 0x400200, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x2, + Value: 0x40021C, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x3, + Value: 0x400240, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x4, + Value: 0x400268, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x5, + Value: 0x400288, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x6, + Value: 0x4002E8, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x7, + Value: 0x400326, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x8, + Value: 0x400330, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x9, + Value: 0x400350, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xA, + Value: 0x400368, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xB, + Value: 0x400398, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xC, + Value: 0x4003B0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xD, + Value: 0x4003E0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xE, + Value: 0x400594, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xF, + Value: 0x4005A4, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x10, + Value: 0x4005B8, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x11, + Value: 0x4005E0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x12, + Value: 0x600688, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x13, + Value: 0x600698, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x14, + Value: 0x6006A8, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x15, + Value: 0x6006B0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x16, + Value: 0x600850, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x17, + Value: 0x600858, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x18, + Value: 0x600880, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x19, + Value: 0x600898, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1A, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1B, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1C, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1D, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1E, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1F, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x20, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x21, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "init.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "initfini.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "call_gmon_start", + Info: 0x2, + Other: 0x0, + Section: 0xD, + Value: 0x40040C, + Size: 0x0, + }, + Symbol{ + Name: "crtstuff.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "__CTOR_LIST__", + Info: 0x1, + Other: 0x0, + Section: 0x12, + Value: 0x600688, + Size: 0x0, + }, + Symbol{ + Name: "__DTOR_LIST__", + Info: 0x1, + Other: 0x0, + Section: 0x13, + Value: 0x600698, + Size: 0x0, + }, + Symbol{ + Name: "__JCR_LIST__", + Info: 0x1, + Other: 0x0, + Section: 0x14, + Value: 0x6006A8, + Size: 0x0, + }, + Symbol{ + Name: "__do_global_dtors_aux", + Info: 0x2, + Other: 0x0, + Section: 0xD, + Value: 0x400430, + Size: 0x0, + }, + Symbol{ + Name: "completed.6183", + Info: 0x1, + Other: 0x0, + Section: 0x19, + Value: 0x600898, + Size: 0x1, + }, + Symbol{ + Name: "p.6181", + Info: 0x1, + Other: 0x0, + Section: 0x18, + Value: 0x600890, + Size: 0x0, + }, + Symbol{ + Name: "frame_dummy", + Info: 0x2, + Other: 0x0, + Section: 0xD, + Value: 0x400470, + Size: 0x0, + }, + Symbol{ + Name: "crtstuff.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "__CTOR_END__", + Info: 0x1, + Other: 0x0, + Section: 0x12, + Value: 0x600690, + Size: 0x0, + }, + Symbol{ + Name: "__DTOR_END__", + Info: 0x1, + Other: 0x0, + Section: 0x13, + Value: 0x6006A0, + Size: 0x0, + }, + Symbol{ + Name: "__FRAME_END__", + Info: 0x1, + Other: 0x0, + Section: 0x11, + Value: 0x400680, + Size: 0x0, + }, + Symbol{ + Name: "__JCR_END__", + Info: 0x1, + Other: 0x0, + Section: 0x14, + Value: 0x6006A8, + Size: 0x0, + }, + Symbol{ + Name: "__do_global_ctors_aux", + Info: 0x2, + Other: 0x0, + Section: 0xD, + Value: 0x400560, + Size: 0x0, + }, + Symbol{ + Name: "initfini.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "hello.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "_GLOBAL_OFFSET_TABLE_", + Info: 0x1, + Other: 0x2, + Section: 0x17, + Value: 0x600858, + Size: 0x0, + }, + Symbol{ + Name: "__init_array_end", + Info: 0x0, + Other: 0x2, + Section: 0x12, + Value: 0x600684, + Size: 0x0, + }, + Symbol{ + Name: "__init_array_start", + Info: 0x0, + Other: 0x2, + Section: 0x12, + Value: 0x600684, + Size: 0x0, + }, + Symbol{ + Name: "_DYNAMIC", + Info: 0x1, + Other: 0x2, + Section: 0x15, + Value: 0x6006B0, + Size: 0x0, + }, + Symbol{ + Name: "data_start", + Info: 0x20, + Other: 0x0, + Section: 0x18, + Value: 0x600880, + Size: 0x0, + }, + Symbol{ + Name: "__libc_csu_fini", + Info: 0x12, + Other: 0x0, + Section: 0xD, + Value: 0x4004C0, + Size: 0x2, + }, + Symbol{ + Name: "_start", + Info: 0x12, + Other: 0x0, + Section: 0xD, + Value: 0x4003E0, + Size: 0x0, + }, + Symbol{ + Name: "__gmon_start__", + Info: 0x20, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "_Jv_RegisterClasses", + Info: 0x20, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "puts@@GLIBC_2.2.5", + Info: 0x12, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x18C, + }, + Symbol{ + Name: "_fini", + Info: 0x12, + Other: 0x0, + Section: 0xE, + Value: 0x400594, + Size: 0x0, + }, + Symbol{ + Name: "__libc_start_main@@GLIBC_2.2.5", + Info: 0x12, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x1C2, + }, + Symbol{ + Name: "_IO_stdin_used", + Info: 0x11, + Other: 0x0, + Section: 0xF, + Value: 0x4005A4, + Size: 0x4, + }, + Symbol{ + Name: "__data_start", + Info: 0x10, + Other: 0x0, + Section: 0x18, + Value: 0x600880, + Size: 0x0, + }, + Symbol{ + Name: "__dso_handle", + Info: 0x11, + Other: 0x2, + Section: 0x18, + Value: 0x600888, + Size: 0x0, + }, + Symbol{ + Name: "__libc_csu_init", + Info: 0x12, + Other: 0x0, + Section: 0xD, + Value: 0x4004D0, + Size: 0x89, + }, + Symbol{ + Name: "__bss_start", + Info: 0x10, + Other: 0x0, + Section: 0xFFF1, + Value: 0x600898, + Size: 0x0, + }, + Symbol{ + Name: "_end", + Info: 0x10, + Other: 0x0, + Section: 0xFFF1, + Value: 0x6008A0, + Size: 0x0, + }, + Symbol{ + Name: "_edata", + Info: 0x10, + Other: 0x0, + Section: 0xFFF1, + Value: 0x600898, + Size: 0x0, + }, + Symbol{ + Name: "main", + Info: 0x12, + Other: 0x0, + Section: 0xD, + Value: 0x400498, + Size: 0x1B, + }, + Symbol{ + Name: "_init", + Info: 0x12, + Other: 0x0, + Section: 0xB, + Value: 0x400398, + Size: 0x0, + }, + }, + "testdata/go-relocation-test-clang-x86.obj": { + Symbol{ + Name: "go-relocation-test-clang.c", + Info: 0x4, + Other: 0x0, + Section: 0xFFF1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: ".Linfo_string0", + Info: 0x0, + Other: 0x0, + Section: 0xC, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: ".Linfo_string1", + Info: 0x0, + Other: 0x0, + Section: 0xC, + Value: 0x2C, + Size: 0x0, + }, + Symbol{ + Name: ".Linfo_string2", + Info: 0x0, + Other: 0x0, + Section: 0xC, + Value: 0x47, + Size: 0x0, + }, + Symbol{ + Name: ".Linfo_string3", + Info: 0x0, + Other: 0x0, + Section: 0xC, + Value: 0x4C, + Size: 0x0, + }, + Symbol{ + Name: ".Linfo_string4", + Info: 0x0, + Other: 0x0, + Section: 0xC, + Value: 0x4E, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x1, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x2, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x3, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x4, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x6, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x7, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x8, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xA, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xC, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xD, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xE, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0xF, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "", + Info: 0x3, + Other: 0x0, + Section: 0x10, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "v", + Info: 0x11, + Other: 0x0, + Section: 0xFFF2, + Value: 0x4, + Size: 0x4, + }, + }, + "testdata/hello-world-core.gz": {}, +} + +var dynamicSymbolsGolden = map[string][]Symbol{ + "testdata/gcc-amd64-linux-exec": { + Symbol{ + Name: "__gmon_start__", + Info: 0x20, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x0, + }, + Symbol{ + Name: "puts", + Info: 0x12, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x18C, + }, + Symbol{ + Name: "__libc_start_main", + Info: 0x12, + Other: 0x0, + Section: 0x0, + Value: 0x0, + Size: 0x1C2, + }, + }, + "testdata/go-relocation-test-clang-x86.obj": {}, + "testdata/hello-world-core.gz": {}, +}