Imported Upstream version 1.1~hg20130304upstream/1.1_hg20130304

4 files changed, 144 insertions, 43 deletions

diff --git a/src/pkg/debug/elf/file.go b/src/pkg/debug/elf/file.go
index 184ca8375..acb9817af 100644
--- a/src/pkg/debug/elf/file.go
+++ b/src/pkg/debug/elf/file.go
@@ -31,6 +31,7 @@ type FileHeader struct {
 	ByteOrder  binary.ByteOrder
 	Type       Type
 	Machine    Machine
+	Entry      uint64
 }
 
 // A File represents an open ELF file.
@@ -240,6 +241,7 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		}
 		f.Type = Type(hdr.Type)
 		f.Machine = Machine(hdr.Machine)
+		f.Entry = uint64(hdr.Entry)
 		if v := Version(hdr.Version); v != f.Version {
 			return nil, &FormatError{0, "mismatched ELF version", v}
 		}
@@ -258,6 +260,7 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		}
 		f.Type = Type(hdr.Type)
 		f.Machine = Machine(hdr.Machine)
+		f.Entry = uint64(hdr.Entry)
 		if v := Version(hdr.Version); v != f.Version {
 			return nil, &FormatError{0, "mismatched ELF version", v}
 		}
@@ -269,7 +272,8 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		shnum = int(hdr.Shnum)
 		shstrndx = int(hdr.Shstrndx)
 	}
-	if shstrndx < 0 || shstrndx >= shnum {
+
+	if shnum > 0 && shoff > 0 && (shstrndx < 0 || shstrndx >= shnum) {
 		return nil, &FormatError{0, "invalid ELF shstrndx", shstrndx}
 	}
 
@@ -364,6 +368,10 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		f.Sections[i] = s
 	}
 
+	if len(f.Sections) == 0 {
+		return f, nil
+	}
+
 	// Load section header string table.
 	shstrtab, err := f.Sections[shstrndx].Data()
 	if err != nil {
@@ -414,10 +422,6 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
 		return nil, nil, errors.New("cannot load string table section")
 	}
 
-	// The first entry is all zeros.
-	var skip [Sym32Size]byte
-	symtab.Read(skip[0:])
-
 	symbols := make([]Symbol, symtab.Len()/Sym32Size)
 
 	i := 0
@@ -457,10 +461,6 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
 		return nil, nil, errors.New("cannot load string table section")
 	}
 
-	// The first entry is all zeros.
-	var skip [Sym64Size]byte
-	symtab.Read(skip[0:])
-
 	symbols := make([]Symbol, symtab.Len()/Sym64Size)
 
 	i := 0
@@ -705,8 +705,8 @@ func (f *File) gnuVersionInit(str []byte) {
 // gnuVersion adds Library and Version information to sym,
 // which came from offset i of the symbol table.
 func (f *File) gnuVersion(i int, sym *ImportedSymbol) {
-	// Each entry is two bytes; skip undef entry at beginning.
-	i = (i + 1) * 2
+	// Each entry is two bytes.
+	i = i * 2
 	if i >= len(f.gnuVersym) {
 		return
 	}
@@ -723,6 +723,20 @@ func (f *File) gnuVersion(i int, sym *ImportedSymbol) {
 // referred to by the binary f that are expected to be
 // linked with the binary at dynamic link time.
 func (f *File) ImportedLibraries() ([]string, error) {
+	return f.DynString(DT_NEEDED)
+}
+
+// DynString returns the strings listed for the given tag in the file's dynamic
+// section.
+//
+// The tag must be one that takes string values: DT_NEEDED, DT_SONAME, DT_RPATH, or
+// DT_RUNPATH.
+func (f *File) DynString(tag DynTag) ([]string, error) {
+	switch tag {
+	case DT_NEEDED, DT_SONAME, DT_RPATH, DT_RUNPATH:
+	default:
+		return nil, fmt.Errorf("non-string-valued tag %v", tag)
+	}
 	ds := f.SectionByType(SHT_DYNAMIC)
 	if ds == nil {
 		// not dynamic, so no libraries
@@ -738,25 +752,24 @@ func (f *File) ImportedLibraries() ([]string, error) {
 	}
 	var all []string
 	for len(d) > 0 {
-		var tag DynTag
-		var value uint64
+		var t DynTag
+		var v uint64
 		switch f.Class {
 		case ELFCLASS32:
-			tag = DynTag(f.ByteOrder.Uint32(d[0:4]))
-			value = uint64(f.ByteOrder.Uint32(d[4:8]))
+			t = DynTag(f.ByteOrder.Uint32(d[0:4]))
+			v = uint64(f.ByteOrder.Uint32(d[4:8]))
 			d = d[8:]
 		case ELFCLASS64:
-			tag = DynTag(f.ByteOrder.Uint64(d[0:8]))
-			value = f.ByteOrder.Uint64(d[8:16])
+			t = DynTag(f.ByteOrder.Uint64(d[0:8]))
+			v = f.ByteOrder.Uint64(d[8:16])
 			d = d[16:]
 		}
-		if tag == DT_NEEDED {
-			s, ok := getString(str, int(value))
+		if t == tag {
+			s, ok := getString(str, int(v))
 			if ok {
 				all = append(all, s)
 			}
 		}
 	}
-
 	return all, nil
 }
diff --git a/src/pkg/debug/elf/file_test.go b/src/pkg/debug/elf/file_test.go
index 98f2723c8..f9aa7265a 100644
--- a/src/pkg/debug/elf/file_test.go
+++ b/src/pkg/debug/elf/file_test.go
@@ -5,10 +5,14 @@
 package elf
 
 import (
+	"bytes"
+	"compress/gzip"
 	"debug/dwarf"
 	"encoding/binary"
+	"io"
 	"net"
 	"os"
+	"path"
 	"reflect"
 	"runtime"
 	"testing"
@@ -19,12 +23,13 @@ type fileTest struct {
 	hdr      FileHeader
 	sections []SectionHeader
 	progs    []ProgHeader
+	needed   []string
 }
 
 var fileTests = []fileTest{
 	{
 		"testdata/gcc-386-freebsd-exec",
-		FileHeader{ELFCLASS32, ELFDATA2LSB, EV_CURRENT, ELFOSABI_FREEBSD, 0, binary.LittleEndian, ET_EXEC, EM_386},
+		FileHeader{ELFCLASS32, ELFDATA2LSB, EV_CURRENT, ELFOSABI_FREEBSD, 0, binary.LittleEndian, ET_EXEC, EM_386, 0x80483cc},
 		[]SectionHeader{
 			{"", SHT_NULL, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},
 			{".interp", SHT_PROGBITS, SHF_ALLOC, 0x80480d4, 0xd4, 0x15, 0x0, 0x0, 0x1, 0x0},
@@ -64,10 +69,11 @@ var fileTests = []fileTest{
 			{PT_LOAD, PF_R + PF_W, 0x5fc, 0x80495fc, 0x80495fc, 0xd8, 0xf8, 0x1000},
 			{PT_DYNAMIC, PF_R + PF_W, 0x60c, 0x804960c, 0x804960c, 0x98, 0x98, 0x4},
 		},
+		[]string{"libc.so.6"},
 	},
 	{
 		"testdata/gcc-amd64-linux-exec",
-		FileHeader{ELFCLASS64, ELFDATA2LSB, EV_CURRENT, ELFOSABI_NONE, 0, binary.LittleEndian, ET_EXEC, EM_X86_64},
+		FileHeader{ELFCLASS64, ELFDATA2LSB, EV_CURRENT, ELFOSABI_NONE, 0, binary.LittleEndian, ET_EXEC, EM_X86_64, 0x4003e0},
 		[]SectionHeader{
 			{"", SHT_NULL, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},
 			{".interp", SHT_PROGBITS, SHF_ALLOC, 0x400200, 0x200, 0x1c, 0x0, 0x0, 0x1, 0x0},
@@ -117,6 +123,32 @@ var fileTests = []fileTest{
 			{PT_LOOS + 0x474E550, PF_R, 0x5b8, 0x4005b8, 0x4005b8, 0x24, 0x24, 0x4},
 			{PT_LOOS + 0x474E551, PF_R + PF_W, 0x0, 0x0, 0x0, 0x0, 0x0, 0x8},
 		},
+		[]string{"libc.so.6"},
+	},
+	{
+		"testdata/hello-world-core.gz",
+		FileHeader{ELFCLASS64, ELFDATA2LSB, EV_CURRENT, ELFOSABI_NONE, 0x0, binary.LittleEndian, ET_CORE, EM_X86_64, 0x0},
+		[]SectionHeader{},
+		[]ProgHeader{
+			{Type: PT_NOTE, Flags: 0x0, Off: 0x3f8, Vaddr: 0x0, Paddr: 0x0, Filesz: 0x8ac, Memsz: 0x0, Align: 0x0},
+			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0x1000, Vaddr: 0x400000, Paddr: 0x0, Filesz: 0x0, Memsz: 0x1000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_R, Off: 0x1000, Vaddr: 0x401000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x2000, Vaddr: 0x402000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0x3000, Vaddr: 0x7f54078b8000, Paddr: 0x0, Filesz: 0x0, Memsz: 0x1b5000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: 0x0, Off: 0x3000, Vaddr: 0x7f5407a6d000, Paddr: 0x0, Filesz: 0x0, Memsz: 0x1ff000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_R, Off: 0x3000, Vaddr: 0x7f5407c6c000, Paddr: 0x0, Filesz: 0x4000, Memsz: 0x4000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x7000, Vaddr: 0x7f5407c70000, Paddr: 0x0, Filesz: 0x2000, Memsz: 0x2000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x9000, Vaddr: 0x7f5407c72000, Paddr: 0x0, Filesz: 0x5000, Memsz: 0x5000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0xe000, Vaddr: 0x7f5407c77000, Paddr: 0x0, Filesz: 0x0, Memsz: 0x22000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0xe000, Vaddr: 0x7f5407e81000, Paddr: 0x0, Filesz: 0x3000, Memsz: 0x3000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x11000, Vaddr: 0x7f5407e96000, Paddr: 0x0, Filesz: 0x3000, Memsz: 0x3000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_R, Off: 0x14000, Vaddr: 0x7f5407e99000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x15000, Vaddr: 0x7f5407e9a000, Paddr: 0x0, Filesz: 0x2000, Memsz: 0x2000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_W + PF_R, Off: 0x17000, Vaddr: 0x7fff79972000, Paddr: 0x0, Filesz: 0x23000, Memsz: 0x23000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0x3a000, Vaddr: 0x7fff799f8000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
+			{Type: PT_LOAD, Flags: PF_X + PF_R, Off: 0x3b000, Vaddr: 0xffffffffff600000, Paddr: 0x0, Filesz: 0x1000, Memsz: 0x1000, Align: 0x1000},
+		},
+		nil,
 	},
 }
 
@@ -124,9 +156,18 @@ func TestOpen(t *testing.T) {
 	for i := range fileTests {
 		tt := &fileTests[i]
 
-		f, err := Open(tt.file)
+		var f *File
+		var err error
+		if path.Ext(tt.file) == ".gz" {
+			var r io.ReaderAt
+			if r, err = decompress(tt.file); err == nil {
+				f, err = NewFile(r)
+			}
+		} else {
+			f, err = Open(tt.file)
+		}
 		if err != nil {
-			t.Error(err)
+			t.Errorf("cannot open file %s: %v", tt.file, err)
 			continue
 		}
 		if !reflect.DeepEqual(f.FileHeader, tt.hdr) {
@@ -161,26 +202,69 @@ func TestOpen(t *testing.T) {
 		if tn != fn {
 			t.Errorf("open %s: len(Progs) = %d, want %d", tt.file, fn, tn)
 		}
+		tl := tt.needed
+		fl, err := f.ImportedLibraries()
+		if err != nil {
+			t.Error(err)
+		}
+		if !reflect.DeepEqual(tl, fl) {
+			t.Errorf("open %s: DT_NEEDED = %v, want %v", tt.file, tl, fl)
+		}
 	}
 }
 
+// elf.NewFile requires io.ReaderAt, which compress/gzip cannot
+// provide. Decompress the file to a bytes.Reader.
+func decompress(gz string) (io.ReaderAt, error) {
+	in, err := os.Open(gz)
+	if err != nil {
+		return nil, err
+	}
+	defer in.Close()
+	r, err := gzip.NewReader(in)
+	if err != nil {
+		return nil, err
+	}
+	var out bytes.Buffer
+	_, err = io.Copy(&out, r)
+	return bytes.NewReader(out.Bytes()), err
+}
+
+type relocationTestEntry struct {
+	entryNumber int
+	entry       *dwarf.Entry
+}
+
 type relocationTest struct {
-	file       string
-	firstEntry *dwarf.Entry
+	file    string
+	entries []relocationTestEntry
 }
 
 var relocationTests = []relocationTest{
 	{
 		"testdata/go-relocation-test-gcc441-x86-64.obj",
-		&dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}},
+		[]relocationTestEntry{
+			{0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}},
+		},
 	},
 	{
 		"testdata/go-relocation-test-gcc441-x86.obj",
-		&dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "t.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x5)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}},
+		[]relocationTestEntry{
+			{0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.4.1"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "t.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x5)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}},
+		},
 	},
 	{
 		"testdata/go-relocation-test-gcc424-x86-64.obj",
-		&dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.2.4 (Ubuntu 4.2.4-1ubuntu4)"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test-gcc424.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}},
+		[]relocationTestEntry{
+			{0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "GNU C 4.2.4 (Ubuntu 4.2.4-1ubuntu4)"}, {Attr: dwarf.AttrLanguage, Val: int64(1)}, {Attr: dwarf.AttrName, Val: "go-relocation-test-gcc424.c"}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}, {Attr: dwarf.AttrLowpc, Val: uint64(0x0)}, {Attr: dwarf.AttrHighpc, Val: uint64(0x6)}, {Attr: dwarf.AttrStmtList, Val: int64(0)}}}},
+		},
+	},
+	{
+		"testdata/gcc-amd64-openbsd-debug-with-rela.obj",
+		[]relocationTestEntry{
+			{203, &dwarf.Entry{Offset: 0xc62, Tag: dwarf.TagMember, Children: false, Field: []dwarf.Field{{Attr: dwarf.AttrName, Val: "it_interval"}, {Attr: dwarf.AttrDeclFile, Val: int64(7)}, {Attr: dwarf.AttrDeclLine, Val: int64(236)}, {Attr: dwarf.AttrType, Val: dwarf.Offset(0xb7f)}, {Attr: dwarf.AttrDataMemberLoc, Val: []byte{0x23, 0x0}}}}},
+			{204, &dwarf.Entry{Offset: 0xc70, Tag: dwarf.TagMember, Children: false, Field: []dwarf.Field{{Attr: dwarf.AttrName, Val: "it_value"}, {Attr: dwarf.AttrDeclFile, Val: int64(7)}, {Attr: dwarf.AttrDeclLine, Val: int64(237)}, {Attr: dwarf.AttrType, Val: dwarf.Offset(0xb7f)}, {Attr: dwarf.AttrDataMemberLoc, Val: []byte{0x23, 0x10}}}}},
+		},
 	},
 }
 
@@ -196,20 +280,24 @@ func TestDWARFRelocations(t *testing.T) {
 			t.Error(err)
 			continue
 		}
-		reader := dwarf.Reader()
-		// Checking only the first entry is sufficient since it has
-		// many different strings. If the relocation had failed, all
-		// the string offsets would be zero and all the strings would
-		// end up being the same.
-		firstEntry, err := reader.Next()
-		if err != nil {
-			t.Error(err)
-			continue
-		}
-
-		if !reflect.DeepEqual(test.firstEntry, firstEntry) {
-			t.Errorf("#%d: mismatch: got:%#v want:%#v", i, firstEntry, test.firstEntry)
-			continue
+		for _, testEntry := range test.entries {
+			reader := dwarf.Reader()
+			for j := 0; j < testEntry.entryNumber; j++ {
+				entry, err := reader.Next()
+				if entry == nil || err != nil {
+					t.Errorf("Failed to skip to entry %d: %v", testEntry.entryNumber, err)
+					continue
+				}
+			}
+			entry, err := reader.Next()
+			if err != nil {
+				t.Error(err)
+				continue
+			}
+			if !reflect.DeepEqual(testEntry.entry, entry) {
+				t.Errorf("#%d/%d: mismatch: got:%#v want:%#v", i, testEntry.entryNumber, entry, testEntry.entry)
+				continue
+			}
 		}
 	}
 }
diff --git a/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj b/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj
new file mode 100644
index 000000000..f62b1ea1c
--- /dev/null
+++ b/src/pkg/debug/elf/testdata/gcc-amd64-openbsd-debug-with-rela.obj
diff --git a/src/pkg/debug/elf/testdata/hello-world-core.gz b/src/pkg/debug/elf/testdata/hello-world-core.gz
new file mode 100644
index 000000000..806af6edb
--- /dev/null
+++ b/src/pkg/debug/elf/testdata/hello-world-core.gz