debug/pe: introduce StringTable type

PE specification requires that long section and symbol names
are stored in PE string table. Introduce StringTable that
implements this functionality. Only string table reading is
implemented.

Updates #15345

Change-Id: Ib9638617f2ab1881ad707111d96fc68b0e47340e
Reviewed-on: https://go-review.googlesource.com/22181
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/src/debug/pe/file.go b/src/debug/pe/file.go
index bfc4cf8a18..f7b74e92a4 100644
--- a/src/debug/pe/file.go
+++ b/src/debug/pe/file.go
@@ -21,6 +21,7 @@ type File struct {
 	OptionalHeader interface{} // of type *OptionalHeader32 or *OptionalHeader64
 	Sections       []*Section
 	Symbols        []*Symbol
+	StringTable    StringTable
 
 	closer io.Closer
 }
@@ -133,6 +134,14 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		return nil, errors.New("Invalid PE File Format.")
 	}
 
+	var err error
+
+	// Read string table.
+	f.StringTable, err = readStringTable(&f.FileHeader, sr)
+	if err != nil {
+		return nil, err
+	}
+
 	var ss []byte
 	if f.FileHeader.NumberOfSymbols > 0 {
 		// Get COFF string table, which is located at the end of the COFF symbol table.
@@ -237,13 +246,6 @@ func NewFile(r io.ReaderAt) (*File, error) {
 	return f, nil
 }
 
-func cstring(b []byte) string {
-	var i int
-	for i = 0; i < len(b) && b[i] != 0; i++ {
-	}
-	return string(b[0:i])
-}
-
 // getString extracts a string from symbol string table.
 func getString(section []byte, start int) (string, bool) {
 	if start < 0 || start >= len(section) {