llvm/lib/Object/Archive.cpp
Jake Ehrlich 9a8a8159d3 Make 32-bit member offset in Archive::Symbol::getMember 64-bit
When accessing a member for a symbol with an offset greater than 2^32 -
1 the current Archive::Symbol::getMember implementation will overflow
and cause unexpected behavior. This change simply fixes that. In
particular if you call "llvm-nm --print-armap" on an archive that has
this behavior you'll get an error.

Differential Revision: https://reviews.llvm.org/D39379

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316801 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-27 21:47:38 +00:00

994 lines
34 KiB
C++

//===- Archive.cpp - ar File Format implementation ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the ArchiveObjectFile class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/Archive.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Object/Binary.h"
#include "llvm/Object/Error.h"
#include "llvm/Support/Chrono.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorOr.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <cstring>
#include <memory>
#include <string>
#include <system_error>
using namespace llvm;
using namespace object;
using namespace llvm::support::endian;
static const char *const Magic = "!<arch>\n";
static const char *const ThinMagic = "!<thin>\n";
void Archive::anchor() {}
static Error
malformedError(Twine Msg) {
std::string StringMsg = "truncated or malformed archive (" + Msg.str() + ")";
return make_error<GenericBinaryError>(std::move(StringMsg),
object_error::parse_failed);
}
ArchiveMemberHeader::ArchiveMemberHeader(const Archive *Parent,
const char *RawHeaderPtr,
uint64_t Size, Error *Err)
: Parent(Parent),
ArMemHdr(reinterpret_cast<const ArMemHdrType *>(RawHeaderPtr)) {
if (RawHeaderPtr == nullptr)
return;
ErrorAsOutParameter ErrAsOutParam(Err);
if (Size < sizeof(ArMemHdrType)) {
if (Err) {
std::string Msg("remaining size of archive too small for next archive "
"member header ");
Expected<StringRef> NameOrErr = getName(Size);
if (!NameOrErr) {
consumeError(NameOrErr.takeError());
uint64_t Offset = RawHeaderPtr - Parent->getData().data();
*Err = malformedError(Msg + "at offset " + Twine(Offset));
} else
*Err = malformedError(Msg + "for " + NameOrErr.get());
}
return;
}
if (ArMemHdr->Terminator[0] != '`' || ArMemHdr->Terminator[1] != '\n') {
if (Err) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(StringRef(ArMemHdr->Terminator,
sizeof(ArMemHdr->Terminator)));
OS.flush();
std::string Msg("terminator characters in archive member \"" + Buf +
"\" not the correct \"`\\n\" values for the archive "
"member header ");
Expected<StringRef> NameOrErr = getName(Size);
if (!NameOrErr) {
consumeError(NameOrErr.takeError());
uint64_t Offset = RawHeaderPtr - Parent->getData().data();
*Err = malformedError(Msg + "at offset " + Twine(Offset));
} else
*Err = malformedError(Msg + "for " + NameOrErr.get());
}
return;
}
}
// This gets the raw name from the ArMemHdr->Name field and checks that it is
// valid for the kind of archive. If it is not valid it returns an Error.
Expected<StringRef> ArchiveMemberHeader::getRawName() const {
char EndCond;
auto Kind = Parent->kind();
if (Kind == Archive::K_BSD || Kind == Archive::K_DARWIN64) {
if (ArMemHdr->Name[0] == ' ') {
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("name contains a leading space for archive member "
"header at offset " + Twine(Offset));
}
EndCond = ' ';
}
else if (ArMemHdr->Name[0] == '/' || ArMemHdr->Name[0] == '#')
EndCond = ' ';
else
EndCond = '/';
StringRef::size_type end =
StringRef(ArMemHdr->Name, sizeof(ArMemHdr->Name)).find(EndCond);
if (end == StringRef::npos)
end = sizeof(ArMemHdr->Name);
assert(end <= sizeof(ArMemHdr->Name) && end > 0);
// Don't include the EndCond if there is one.
return StringRef(ArMemHdr->Name, end);
}
// This gets the name looking up long names. Size is the size of the archive
// member including the header, so the size of any name following the header
// is checked to make sure it does not overflow.
Expected<StringRef> ArchiveMemberHeader::getName(uint64_t Size) const {
// This can be called from the ArchiveMemberHeader constructor when the
// archive header is truncated to produce an error message with the name.
// Make sure the name field is not truncated.
if (Size < offsetof(ArMemHdrType, Name) + sizeof(ArMemHdr->Name)) {
uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("archive header truncated before the name field "
"for archive member header at offset " +
Twine(ArchiveOffset));
}
// The raw name itself can be invalid.
Expected<StringRef> NameOrErr = getRawName();
if (!NameOrErr)
return NameOrErr.takeError();
StringRef Name = NameOrErr.get();
// Check if it's a special name.
if (Name[0] == '/') {
if (Name.size() == 1) // Linker member.
return Name;
if (Name.size() == 2 && Name[1] == '/') // String table.
return Name;
// It's a long name.
// Get the string table offset.
std::size_t StringOffset;
if (Name.substr(1).rtrim(' ').getAsInteger(10, StringOffset)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(Name.substr(1).rtrim(' '));
OS.flush();
uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("long name offset characters after the '/' are "
"not all decimal numbers: '" + Buf + "' for "
"archive member header at offset " +
Twine(ArchiveOffset));
}
// Verify it.
if (StringOffset >= Parent->getStringTable().size()) {
uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("long name offset " + Twine(StringOffset) + " past "
"the end of the string table for archive member "
"header at offset " + Twine(ArchiveOffset));
}
const char *addr = Parent->getStringTable().begin() + StringOffset;
// GNU long file names end with a "/\n".
if (Parent->kind() == Archive::K_GNU ||
Parent->kind() == Archive::K_GNU64) {
StringRef::size_type End = StringRef(addr).find('\n');
return StringRef(addr, End - 1);
}
return addr;
}
if (Name.startswith("#1/")) {
uint64_t NameLength;
if (Name.substr(3).rtrim(' ').getAsInteger(10, NameLength)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(Name.substr(3).rtrim(' '));
OS.flush();
uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("long name length characters after the #1/ are "
"not all decimal numbers: '" + Buf + "' for "
"archive member header at offset " +
Twine(ArchiveOffset));
}
if (getSizeOf() + NameLength > Size) {
uint64_t ArchiveOffset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("long name length: " + Twine(NameLength) +
" extends past the end of the member or archive "
"for archive member header at offset " +
Twine(ArchiveOffset));
}
return StringRef(reinterpret_cast<const char *>(ArMemHdr) + getSizeOf(),
NameLength).rtrim('\0');
}
// It is not a long name so trim the blanks at the end of the name.
if (Name[Name.size() - 1] != '/')
return Name.rtrim(' ');
// It's a simple name.
return Name.drop_back(1);
}
Expected<uint32_t> ArchiveMemberHeader::getSize() const {
uint32_t Ret;
if (StringRef(ArMemHdr->Size,
sizeof(ArMemHdr->Size)).rtrim(" ").getAsInteger(10, Ret)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(StringRef(ArMemHdr->Size,
sizeof(ArMemHdr->Size)).rtrim(" "));
OS.flush();
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("characters in size field in archive header are not "
"all decimal numbers: '" + Buf + "' for archive "
"member header at offset " + Twine(Offset));
}
return Ret;
}
Expected<sys::fs::perms> ArchiveMemberHeader::getAccessMode() const {
unsigned Ret;
if (StringRef(ArMemHdr->AccessMode,
sizeof(ArMemHdr->AccessMode)).rtrim(' ').getAsInteger(8, Ret)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(StringRef(ArMemHdr->AccessMode,
sizeof(ArMemHdr->AccessMode)).rtrim(" "));
OS.flush();
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("characters in AccessMode field in archive header "
"are not all decimal numbers: '" + Buf + "' for the "
"archive member header at offset " + Twine(Offset));
}
return static_cast<sys::fs::perms>(Ret);
}
Expected<sys::TimePoint<std::chrono::seconds>>
ArchiveMemberHeader::getLastModified() const {
unsigned Seconds;
if (StringRef(ArMemHdr->LastModified,
sizeof(ArMemHdr->LastModified)).rtrim(' ')
.getAsInteger(10, Seconds)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(StringRef(ArMemHdr->LastModified,
sizeof(ArMemHdr->LastModified)).rtrim(" "));
OS.flush();
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("characters in LastModified field in archive header "
"are not all decimal numbers: '" + Buf + "' for the "
"archive member header at offset " + Twine(Offset));
}
return sys::toTimePoint(Seconds);
}
Expected<unsigned> ArchiveMemberHeader::getUID() const {
unsigned Ret;
StringRef User = StringRef(ArMemHdr->UID, sizeof(ArMemHdr->UID)).rtrim(' ');
if (User.empty())
return 0;
if (User.getAsInteger(10, Ret)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(User);
OS.flush();
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("characters in UID field in archive header "
"are not all decimal numbers: '" + Buf + "' for the "
"archive member header at offset " + Twine(Offset));
}
return Ret;
}
Expected<unsigned> ArchiveMemberHeader::getGID() const {
unsigned Ret;
StringRef Group = StringRef(ArMemHdr->GID, sizeof(ArMemHdr->GID)).rtrim(' ');
if (Group.empty())
return 0;
if (Group.getAsInteger(10, Ret)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(Group);
OS.flush();
uint64_t Offset = reinterpret_cast<const char *>(ArMemHdr) -
Parent->getData().data();
return malformedError("characters in GID field in archive header "
"are not all decimal numbers: '" + Buf + "' for the "
"archive member header at offset " + Twine(Offset));
}
return Ret;
}
Archive::Child::Child(const Archive *Parent, StringRef Data,
uint16_t StartOfFile)
: Parent(Parent), Header(Parent, Data.data(), Data.size(), nullptr),
Data(Data), StartOfFile(StartOfFile) {
}
Archive::Child::Child(const Archive *Parent, const char *Start, Error *Err)
: Parent(Parent),
Header(Parent, Start,
Parent
? Parent->getData().size() - (Start - Parent->getData().data())
: 0, Err) {
if (!Start)
return;
// If we are pointed to real data, Start is not a nullptr, then there must be
// a non-null Err pointer available to report malformed data on. Only in
// the case sentinel value is being constructed is Err is permitted to be a
// nullptr.
assert(Err && "Err can't be nullptr if Start is not a nullptr");
ErrorAsOutParameter ErrAsOutParam(Err);
// If there was an error in the construction of the Header
// then just return with the error now set.
if (*Err)
return;
uint64_t Size = Header.getSizeOf();
Data = StringRef(Start, Size);
Expected<bool> isThinOrErr = isThinMember();
if (!isThinOrErr) {
*Err = isThinOrErr.takeError();
return;
}
bool isThin = isThinOrErr.get();
if (!isThin) {
Expected<uint64_t> MemberSize = getRawSize();
if (!MemberSize) {
*Err = MemberSize.takeError();
return;
}
Size += MemberSize.get();
Data = StringRef(Start, Size);
}
// Setup StartOfFile and PaddingBytes.
StartOfFile = Header.getSizeOf();
// Don't include attached name.
Expected<StringRef> NameOrErr = getRawName();
if (!NameOrErr){
*Err = NameOrErr.takeError();
return;
}
StringRef Name = NameOrErr.get();
if (Name.startswith("#1/")) {
uint64_t NameSize;
if (Name.substr(3).rtrim(' ').getAsInteger(10, NameSize)) {
std::string Buf;
raw_string_ostream OS(Buf);
OS.write_escaped(Name.substr(3).rtrim(' '));
OS.flush();
uint64_t Offset = Start - Parent->getData().data();
*Err = malformedError("long name length characters after the #1/ are "
"not all decimal numbers: '" + Buf + "' for "
"archive member header at offset " +
Twine(Offset));
return;
}
StartOfFile += NameSize;
}
}
Expected<uint64_t> Archive::Child::getSize() const {
if (Parent->IsThin) {
Expected<uint32_t> Size = Header.getSize();
if (!Size)
return Size.takeError();
return Size.get();
}
return Data.size() - StartOfFile;
}
Expected<uint64_t> Archive::Child::getRawSize() const {
return Header.getSize();
}
Expected<bool> Archive::Child::isThinMember() const {
Expected<StringRef> NameOrErr = Header.getRawName();
if (!NameOrErr)
return NameOrErr.takeError();
StringRef Name = NameOrErr.get();
return Parent->IsThin && Name != "/" && Name != "//";
}
Expected<std::string> Archive::Child::getFullName() const {
Expected<bool> isThin = isThinMember();
if (!isThin)
return isThin.takeError();
assert(isThin.get());
Expected<StringRef> NameOrErr = getName();
if (!NameOrErr)
return NameOrErr.takeError();
StringRef Name = *NameOrErr;
if (sys::path::is_absolute(Name))
return Name;
SmallString<128> FullName = sys::path::parent_path(
Parent->getMemoryBufferRef().getBufferIdentifier());
sys::path::append(FullName, Name);
return StringRef(FullName);
}
Expected<StringRef> Archive::Child::getBuffer() const {
Expected<bool> isThinOrErr = isThinMember();
if (!isThinOrErr)
return isThinOrErr.takeError();
bool isThin = isThinOrErr.get();
if (!isThin) {
Expected<uint32_t> Size = getSize();
if (!Size)
return Size.takeError();
return StringRef(Data.data() + StartOfFile, Size.get());
}
Expected<std::string> FullNameOrErr = getFullName();
if (!FullNameOrErr)
return FullNameOrErr.takeError();
const std::string &FullName = *FullNameOrErr;
ErrorOr<std::unique_ptr<MemoryBuffer>> Buf = MemoryBuffer::getFile(FullName);
if (std::error_code EC = Buf.getError())
return errorCodeToError(EC);
Parent->ThinBuffers.push_back(std::move(*Buf));
return Parent->ThinBuffers.back()->getBuffer();
}
Expected<Archive::Child> Archive::Child::getNext() const {
size_t SpaceToSkip = Data.size();
// If it's odd, add 1 to make it even.
if (SpaceToSkip & 1)
++SpaceToSkip;
const char *NextLoc = Data.data() + SpaceToSkip;
// Check to see if this is at the end of the archive.
if (NextLoc == Parent->Data.getBufferEnd())
return Child(nullptr, nullptr, nullptr);
// Check to see if this is past the end of the archive.
if (NextLoc > Parent->Data.getBufferEnd()) {
std::string Msg("offset to next archive member past the end of the archive "
"after member ");
Expected<StringRef> NameOrErr = getName();
if (!NameOrErr) {
consumeError(NameOrErr.takeError());
uint64_t Offset = Data.data() - Parent->getData().data();
return malformedError(Msg + "at offset " + Twine(Offset));
} else
return malformedError(Msg + NameOrErr.get());
}
Error Err = Error::success();
Child Ret(Parent, NextLoc, &Err);
if (Err)
return std::move(Err);
return Ret;
}
uint64_t Archive::Child::getChildOffset() const {
const char *a = Parent->Data.getBuffer().data();
const char *c = Data.data();
uint64_t offset = c - a;
return offset;
}
Expected<StringRef> Archive::Child::getName() const {
Expected<uint64_t> RawSizeOrErr = getRawSize();
if (!RawSizeOrErr)
return RawSizeOrErr.takeError();
uint64_t RawSize = RawSizeOrErr.get();
Expected<StringRef> NameOrErr = Header.getName(Header.getSizeOf() + RawSize);
if (!NameOrErr)
return NameOrErr.takeError();
StringRef Name = NameOrErr.get();
return Name;
}
Expected<MemoryBufferRef> Archive::Child::getMemoryBufferRef() const {
Expected<StringRef> NameOrErr = getName();
if (!NameOrErr)
return NameOrErr.takeError();
StringRef Name = NameOrErr.get();
Expected<StringRef> Buf = getBuffer();
if (!Buf)
return Buf.takeError();
return MemoryBufferRef(*Buf, Name);
}
Expected<std::unique_ptr<Binary>>
Archive::Child::getAsBinary(LLVMContext *Context) const {
Expected<MemoryBufferRef> BuffOrErr = getMemoryBufferRef();
if (!BuffOrErr)
return BuffOrErr.takeError();
auto BinaryOrErr = createBinary(BuffOrErr.get(), Context);
if (BinaryOrErr)
return std::move(*BinaryOrErr);
return BinaryOrErr.takeError();
}
Expected<std::unique_ptr<Archive>> Archive::create(MemoryBufferRef Source) {
Error Err = Error::success();
std::unique_ptr<Archive> Ret(new Archive(Source, Err));
if (Err)
return std::move(Err);
return std::move(Ret);
}
void Archive::setFirstRegular(const Child &C) {
FirstRegularData = C.Data;
FirstRegularStartOfFile = C.StartOfFile;
}
Archive::Archive(MemoryBufferRef Source, Error &Err)
: Binary(Binary::ID_Archive, Source) {
ErrorAsOutParameter ErrAsOutParam(&Err);
StringRef Buffer = Data.getBuffer();
// Check for sufficient magic.
if (Buffer.startswith(ThinMagic)) {
IsThin = true;
} else if (Buffer.startswith(Magic)) {
IsThin = false;
} else {
Err = make_error<GenericBinaryError>("File too small to be an archive",
object_error::invalid_file_type);
return;
}
// Make sure Format is initialized before any call to
// ArchiveMemberHeader::getName() is made. This could be a valid empty
// archive which is the same in all formats. So claiming it to be gnu to is
// fine if not totally correct before we look for a string table or table of
// contents.
Format = K_GNU;
// Get the special members.
child_iterator I = child_begin(Err, false);
if (Err)
return;
child_iterator E = child_end();
// See if this is a valid empty archive and if so return.
if (I == E) {
Err = Error::success();
return;
}
const Child *C = &*I;
auto Increment = [&]() {
++I;
if (Err)
return true;
C = &*I;
return false;
};
Expected<StringRef> NameOrErr = C->getRawName();
if (!NameOrErr) {
Err = NameOrErr.takeError();
return;
}
StringRef Name = NameOrErr.get();
// Below is the pattern that is used to figure out the archive format
// GNU archive format
// First member : / (may exist, if it exists, points to the symbol table )
// Second member : // (may exist, if it exists, points to the string table)
// Note : The string table is used if the filename exceeds 15 characters
// BSD archive format
// First member : __.SYMDEF or "__.SYMDEF SORTED" (the symbol table)
// There is no string table, if the filename exceeds 15 characters or has a
// embedded space, the filename has #1/<size>, The size represents the size
// of the filename that needs to be read after the archive header
// COFF archive format
// First member : /
// Second member : / (provides a directory of symbols)
// Third member : // (may exist, if it exists, contains the string table)
// Note: Microsoft PE/COFF Spec 8.3 says that the third member is present
// even if the string table is empty. However, lib.exe does not in fact
// seem to create the third member if there's no member whose filename
// exceeds 15 characters. So the third member is optional.
if (Name == "__.SYMDEF" || Name == "__.SYMDEF_64") {
if (Name == "__.SYMDEF")
Format = K_BSD;
else // Name == "__.SYMDEF_64"
Format = K_DARWIN64;
// We know that the symbol table is not an external file, but we still must
// check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
SymbolTable = BufOrErr.get();
if (Increment())
return;
setFirstRegular(*C);
Err = Error::success();
return;
}
if (Name.startswith("#1/")) {
Format = K_BSD;
// We know this is BSD, so getName will work since there is no string table.
Expected<StringRef> NameOrErr = C->getName();
if (!NameOrErr) {
Err = NameOrErr.takeError();
return;
}
Name = NameOrErr.get();
if (Name == "__.SYMDEF SORTED" || Name == "__.SYMDEF") {
// We know that the symbol table is not an external file, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
SymbolTable = BufOrErr.get();
if (Increment())
return;
}
else if (Name == "__.SYMDEF_64 SORTED" || Name == "__.SYMDEF_64") {
Format = K_DARWIN64;
// We know that the symbol table is not an external file, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
SymbolTable = BufOrErr.get();
if (Increment())
return;
}
setFirstRegular(*C);
return;
}
// MIPS 64-bit ELF archives use a special format of a symbol table.
// This format is marked by `ar_name` field equals to "/SYM64/".
// For detailed description see page 96 in the following document:
// http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf
bool has64SymTable = false;
if (Name == "/" || Name == "/SYM64/") {
// We know that the symbol table is not an external file, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
SymbolTable = BufOrErr.get();
if (Name == "/SYM64/")
has64SymTable = true;
if (Increment())
return;
if (I == E) {
Err = Error::success();
return;
}
Expected<StringRef> NameOrErr = C->getRawName();
if (!NameOrErr) {
Err = NameOrErr.takeError();
return;
}
Name = NameOrErr.get();
}
if (Name == "//") {
Format = has64SymTable ? K_GNU64 : K_GNU;
// The string table is never an external member, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
StringTable = BufOrErr.get();
if (Increment())
return;
setFirstRegular(*C);
Err = Error::success();
return;
}
if (Name[0] != '/') {
Format = has64SymTable ? K_GNU64 : K_GNU;
setFirstRegular(*C);
Err = Error::success();
return;
}
if (Name != "/") {
Err = errorCodeToError(object_error::parse_failed);
return;
}
Format = K_COFF;
// We know that the symbol table is not an external file, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
SymbolTable = BufOrErr.get();
if (Increment())
return;
if (I == E) {
setFirstRegular(*C);
Err = Error::success();
return;
}
NameOrErr = C->getRawName();
if (!NameOrErr) {
Err = NameOrErr.takeError();
return;
}
Name = NameOrErr.get();
if (Name == "//") {
// The string table is never an external member, but we still
// must check any Expected<> return value.
Expected<StringRef> BufOrErr = C->getBuffer();
if (!BufOrErr) {
Err = BufOrErr.takeError();
return;
}
StringTable = BufOrErr.get();
if (Increment())
return;
}
setFirstRegular(*C);
Err = Error::success();
}
Archive::child_iterator Archive::child_begin(Error &Err,
bool SkipInternal) const {
if (isEmpty())
return child_end();
if (SkipInternal)
return child_iterator(Child(this, FirstRegularData,
FirstRegularStartOfFile),
&Err);
const char *Loc = Data.getBufferStart() + strlen(Magic);
Child C(this, Loc, &Err);
if (Err)
return child_end();
return child_iterator(C, &Err);
}
Archive::child_iterator Archive::child_end() const {
return child_iterator(Child(nullptr, nullptr, nullptr), nullptr);
}
StringRef Archive::Symbol::getName() const {
return Parent->getSymbolTable().begin() + StringIndex;
}
Expected<Archive::Child> Archive::Symbol::getMember() const {
const char *Buf = Parent->getSymbolTable().begin();
const char *Offsets = Buf;
if (Parent->kind() == K_GNU64 || Parent->kind() == K_DARWIN64)
Offsets += sizeof(uint64_t);
else
Offsets += sizeof(uint32_t);
uint64_t Offset = 0;
if (Parent->kind() == K_GNU) {
Offset = read32be(Offsets + SymbolIndex * 4);
} else if (Parent->kind() == K_GNU64) {
Offset = read64be(Offsets + SymbolIndex * 8);
} else if (Parent->kind() == K_BSD) {
// The SymbolIndex is an index into the ranlib structs that start at
// Offsets (the first uint32_t is the number of bytes of the ranlib
// structs). The ranlib structs are a pair of uint32_t's the first
// being a string table offset and the second being the offset into
// the archive of the member that defines the symbol. Which is what
// is needed here.
Offset = read32le(Offsets + SymbolIndex * 8 + 4);
} else if (Parent->kind() == K_DARWIN64) {
// The SymbolIndex is an index into the ranlib_64 structs that start at
// Offsets (the first uint64_t is the number of bytes of the ranlib_64
// structs). The ranlib_64 structs are a pair of uint64_t's the first
// being a string table offset and the second being the offset into
// the archive of the member that defines the symbol. Which is what
// is needed here.
Offset = read64le(Offsets + SymbolIndex * 16 + 8);
} else {
// Skip offsets.
uint32_t MemberCount = read32le(Buf);
Buf += MemberCount * 4 + 4;
uint32_t SymbolCount = read32le(Buf);
if (SymbolIndex >= SymbolCount)
return errorCodeToError(object_error::parse_failed);
// Skip SymbolCount to get to the indices table.
const char *Indices = Buf + 4;
// Get the index of the offset in the file member offset table for this
// symbol.
uint16_t OffsetIndex = read16le(Indices + SymbolIndex * 2);
// Subtract 1 since OffsetIndex is 1 based.
--OffsetIndex;
if (OffsetIndex >= MemberCount)
return errorCodeToError(object_error::parse_failed);
Offset = read32le(Offsets + OffsetIndex * 4);
}
const char *Loc = Parent->getData().begin() + Offset;
Error Err = Error::success();
Child C(Parent, Loc, &Err);
if (Err)
return std::move(Err);
return C;
}
Archive::Symbol Archive::Symbol::getNext() const {
Symbol t(*this);
if (Parent->kind() == K_BSD) {
// t.StringIndex is an offset from the start of the __.SYMDEF or
// "__.SYMDEF SORTED" member into the string table for the ranlib
// struct indexed by t.SymbolIndex . To change t.StringIndex to the
// offset in the string table for t.SymbolIndex+1 we subtract the
// its offset from the start of the string table for t.SymbolIndex
// and add the offset of the string table for t.SymbolIndex+1.
// The __.SYMDEF or "__.SYMDEF SORTED" member starts with a uint32_t
// which is the number of bytes of ranlib structs that follow. The ranlib
// structs are a pair of uint32_t's the first being a string table offset
// and the second being the offset into the archive of the member that
// define the symbol. After that the next uint32_t is the byte count of
// the string table followed by the string table.
const char *Buf = Parent->getSymbolTable().begin();
uint32_t RanlibCount = 0;
RanlibCount = read32le(Buf) / 8;
// If t.SymbolIndex + 1 will be past the count of symbols (the RanlibCount)
// don't change the t.StringIndex as we don't want to reference a ranlib
// past RanlibCount.
if (t.SymbolIndex + 1 < RanlibCount) {
const char *Ranlibs = Buf + 4;
uint32_t CurRanStrx = 0;
uint32_t NextRanStrx = 0;
CurRanStrx = read32le(Ranlibs + t.SymbolIndex * 8);
NextRanStrx = read32le(Ranlibs + (t.SymbolIndex + 1) * 8);
t.StringIndex -= CurRanStrx;
t.StringIndex += NextRanStrx;
}
} else {
// Go to one past next null.
t.StringIndex = Parent->getSymbolTable().find('\0', t.StringIndex) + 1;
}
++t.SymbolIndex;
return t;
}
Archive::symbol_iterator Archive::symbol_begin() const {
if (!hasSymbolTable())
return symbol_iterator(Symbol(this, 0, 0));
const char *buf = getSymbolTable().begin();
if (kind() == K_GNU) {
uint32_t symbol_count = 0;
symbol_count = read32be(buf);
buf += sizeof(uint32_t) + (symbol_count * (sizeof(uint32_t)));
} else if (kind() == K_GNU64) {
uint64_t symbol_count = read64be(buf);
buf += sizeof(uint64_t) + (symbol_count * (sizeof(uint64_t)));
} else if (kind() == K_BSD) {
// The __.SYMDEF or "__.SYMDEF SORTED" member starts with a uint32_t
// which is the number of bytes of ranlib structs that follow. The ranlib
// structs are a pair of uint32_t's the first being a string table offset
// and the second being the offset into the archive of the member that
// define the symbol. After that the next uint32_t is the byte count of
// the string table followed by the string table.
uint32_t ranlib_count = 0;
ranlib_count = read32le(buf) / 8;
const char *ranlibs = buf + 4;
uint32_t ran_strx = 0;
ran_strx = read32le(ranlibs);
buf += sizeof(uint32_t) + (ranlib_count * (2 * (sizeof(uint32_t))));
// Skip the byte count of the string table.
buf += sizeof(uint32_t);
buf += ran_strx;
} else if (kind() == K_DARWIN64) {
// The __.SYMDEF_64 or "__.SYMDEF_64 SORTED" member starts with a uint64_t
// which is the number of bytes of ranlib_64 structs that follow. The
// ranlib_64 structs are a pair of uint64_t's the first being a string
// table offset and the second being the offset into the archive of the
// member that define the symbol. After that the next uint64_t is the byte
// count of the string table followed by the string table.
uint64_t ranlib_count = 0;
ranlib_count = read64le(buf) / 16;
const char *ranlibs = buf + 8;
uint64_t ran_strx = 0;
ran_strx = read64le(ranlibs);
buf += sizeof(uint64_t) + (ranlib_count * (2 * (sizeof(uint64_t))));
// Skip the byte count of the string table.
buf += sizeof(uint64_t);
buf += ran_strx;
} else {
uint32_t member_count = 0;
uint32_t symbol_count = 0;
member_count = read32le(buf);
buf += 4 + (member_count * 4); // Skip offsets.
symbol_count = read32le(buf);
buf += 4 + (symbol_count * 2); // Skip indices.
}
uint32_t string_start_offset = buf - getSymbolTable().begin();
return symbol_iterator(Symbol(this, 0, string_start_offset));
}
Archive::symbol_iterator Archive::symbol_end() const {
return symbol_iterator(Symbol(this, getNumberOfSymbols(), 0));
}
uint32_t Archive::getNumberOfSymbols() const {
if (!hasSymbolTable())
return 0;
const char *buf = getSymbolTable().begin();
if (kind() == K_GNU)
return read32be(buf);
if (kind() == K_GNU64)
return read64be(buf);
if (kind() == K_BSD)
return read32le(buf) / 8;
if (kind() == K_DARWIN64)
return read64le(buf) / 16;
uint32_t member_count = 0;
member_count = read32le(buf);
buf += 4 + (member_count * 4); // Skip offsets.
return read32le(buf);
}
Expected<Optional<Archive::Child>> Archive::findSym(StringRef name) const {
Archive::symbol_iterator bs = symbol_begin();
Archive::symbol_iterator es = symbol_end();
for (; bs != es; ++bs) {
StringRef SymName = bs->getName();
if (SymName == name) {
if (auto MemberOrErr = bs->getMember())
return Child(*MemberOrErr);
else
return MemberOrErr.takeError();
}
}
return Optional<Child>();
}
// Returns true if archive file contains no member file.
bool Archive::isEmpty() const { return Data.getBufferSize() == 8; }
bool Archive::hasSymbolTable() const { return !SymbolTable.empty(); }