[llvm-readobj] Improve error messages on invalid binaries

[sbc100]

Summary

The previous code was discarding the error message from
createBinary() by calling errorToErrorCode().
This meant that such error were always reported unhelpful
as "Invalid data was encountered while parsing the file".

Other tools such as llvm-objdump already produce a more
useful error message in this case.

[sbc100]

rebase

[lhames]

Looks good to me. Thanks Sam!

llvm/trunk/test/Object/invalid.test

 INVALID-SECTION-SIZE: Invalid data was encountered while parsing the file
 
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-symbol-table-size.elf 2>&1 | FileCheck --check-prefix=INVALID-SYMTAB-SIZE %s
 INVALID-SYMTAB-SIZE: size is not a multiple of sh_entsize
 
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-xindex-size.elf 2>&1 | FileCheck --check-prefix=INVALID-XINDEX-SIZE %s
-INVALID-XINDEX-SIZE: Invalid data was encountered while parsing the file.
+INVALID-XINDEX-SIZE: Invalid data was encountered while parsing the file
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-e_shnum.elf 2>&1 | FileCheck --check-prefix=INVALID-SH-NUM %s
 INVALID-SH-NUM: invalid e_phentsize
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-ext-symtab-index.elf-x86-64 2>&1 | \
 RUN:   FileCheck --check-prefix=INVALID-EXT-SYMTAB-INDEX %s
 INVALID-EXT-SYMTAB-INDEX: index past the end of the symbol table
 
 RUN: not llvm-readobj -r %p/Inputs/invalid-relocation-sec-sh_offset.elf-i386 2>&1 | \
 RUN:   FileCheck --check-prefix=INVALID-RELOC-SH-OFFSET %s
 RUN: not llvm-readobj -r %p/Inputs/invalid-relocation-sec-sh_offset.elf-x86-64 2>&1 | \
 RUN:   FileCheck --check-prefix=INVALID-RELOC-SH-OFFSET %s
 INVALID-RELOC-SH-OFFSET: invalid section offset
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-sections-address-alignment.x86-64 2>&1 | \
 RUN:   FileCheck --check-prefix=INVALID-SEC-ADDRESS-ALIGNMENT %s
 INVALID-SEC-ADDRESS-ALIGNMENT: Invalid data was encountered while parsing the file
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-section-size2.elf 2>&1 | \
 RUN:   FileCheck --check-prefix=INVALID-SECTION-SIZE2 %s
 INVALID-SECTION-SIZE2: invalid section offset
 
 RUN: not llvm-readobj -t %p/Inputs/invalid-sections-num.elf 2>&1 | FileCheck --check-prefix=INVALID-SECTION-NUM %s
-INVALID-SECTION-NUM: Invalid data was encountered while parsing the file.
+INVALID-SECTION-NUM: Invalid data was encountered while parsing the file
 
 RUN: not llvm-readobj -r %p/Inputs/invalid-rel-sym.elf 2>&1 | FileCheck --check-prefix=INVALID-REL-SYM %s
 INVALID-REL-SYM: invalid section offset

llvm/trunk/test/tools/llvm-readobj/wasm-invalid.test

+# RUN: yaml2obj %s | not llvm-readobj -t - 2>&1 | FileCheck %s
+
+--- !WASM
+FileHeader:
+  Version:         0x0000000c
+
+# CHECK: Error reading file: <stdin>: Bad version number

llvm/trunk/tools/llvm-readobj/llvm-readobj.cpp

 
 static void reportError(StringRef Input, std::error_code EC) {
   if (Input == "-")
     Input = "<stdin>";
 
   reportError(Twine(Input) + ": " + EC.message());
 }
 
-static void reportError(StringRef Input, StringRef Message) {
-  if (Input == "-")
-    Input = "<stdin>";
-
-  reportError(Twine(Input) + ": " + Message);
-}
-
 static void reportError(StringRef Input, Error Err) {
   if (Input == "-")
     Input = "<stdin>";
   std::string ErrMsg;
   {
     raw_string_ostream ErrStream(ErrMsg);
     logAllUnhandledErrors(std::move(Err), ErrStream, Input + ": ");
   }

 
 /// @brief Dumps each object file in \a Arc;
 static void dumpArchive(const Archive *Arc) {
   Error Err = Error::success();
   for (auto &Child : Arc->children(Err)) {
     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
     if (!ChildOrErr) {
       if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) {
-        std::string Buf;
-        raw_string_ostream OS(Buf);
-        logAllUnhandledErrors(ChildOrErr.takeError(), OS, "");
-        OS.flush();
-        reportError(Arc->getFileName(), Buf);
+        reportError(Arc->getFileName(), ChildOrErr.takeError());
       }
       continue;
     }
     if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
       dumpObject(Obj);
     else if (COFFImportFile *Imp = dyn_cast<COFFImportFile>(&*ChildOrErr.get()))
       dumpCOFFImportFile(Imp);
     else
       reportError(Arc->getFileName(), readobj_error::unrecognized_file_format);
   }
   if (Err)
     reportError(Arc->getFileName(), std::move(Err));
 }
 
 /// @brief Dumps each object file in \a MachO Universal Binary;
 static void dumpMachOUniversalBinary(const MachOUniversalBinary *UBinary) {
   for (const MachOUniversalBinary::ObjectForArch &Obj : UBinary->objects()) {
     Expected<std::unique_ptr<MachOObjectFile>> ObjOrErr = Obj.getAsObjectFile();
     if (ObjOrErr)
       dumpObject(&*ObjOrErr.get());
     else if (auto E = isNotObjectErrorInvalidFileType(ObjOrErr.takeError())) {
-      std::string Buf;
-      raw_string_ostream OS(Buf);
-      logAllUnhandledErrors(ObjOrErr.takeError(), OS, "");
-      OS.flush();
-      reportError(UBinary->getFileName(), Buf);
+      reportError(UBinary->getFileName(), ObjOrErr.takeError());
     }
     else if (Expected<std::unique_ptr<Archive>> AOrErr = Obj.getAsArchive())
       dumpArchive(&*AOrErr.get());
   }
 }
 
 /// @brief Opens \a File and dumps it.
 static void dumpInput(StringRef File) {
 
   // Attempt to open the binary.
   Expected<OwningBinary<Binary>> BinaryOrErr = createBinary(File);
   if (!BinaryOrErr)
-    reportError(File, errorToErrorCode(BinaryOrErr.takeError()));
+    reportError(File, BinaryOrErr.takeError());
   Binary &Binary = *BinaryOrErr.get().getBinary();
 
   if (Archive *Arc = dyn_cast<Archive>(&Binary))
     dumpArchive(Arc);
   else if (MachOUniversalBinary *UBinary =
                dyn_cast<MachOUniversalBinary>(&Binary))
     dumpMachOUniversalBinary(UBinary);
   else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary))