Object: Replace NewArchiveIterator with a simpler NewArchiveMember class. NFCI.

The NewArchiveIterator class has a problem: it requires too much context. Any
memory buffers added to the archive must be stored within an Archive::Member,
which must have an associated Archive. This makes it harder than necessary
to create new archive members (or new archives entirely) from scratch using
memory buffers.

This patch replaces NewArchiveIterator with a NewArchiveMember class that
stores just the memory buffer and the information that goes into the archive
member header.

Differential Revision: http://reviews.llvm.org/D21721

llvm-svn: 274183

1 files changed, 63 insertions, 117 deletions

diff --git a/llvm/lib/Object/ArchiveWriter.cpp b/llvm/lib/Object/ArchiveWriter.cpp
index 93e285cf674..53573262104 100644
--- a/llvm/lib/Object/ArchiveWriter.cpp
+++ b/llvm/lib/Object/ArchiveWriter.cpp
@@ -34,45 +34,61 @@
 
 using namespace llvm;
 
-NewArchiveIterator::NewArchiveIterator(const object::Archive::Child &OldMember,
-                                       StringRef Name)
-    : IsNewMember(false), Name(Name), OldMember(OldMember) {}
-
-NewArchiveIterator::NewArchiveIterator(StringRef FileName)
-    : IsNewMember(true), Name(FileName), OldMember(nullptr, nullptr, nullptr) {}
-
-StringRef NewArchiveIterator::getName() const { return Name; }
-
-bool NewArchiveIterator::isNewMember() const { return IsNewMember; }
-
-const object::Archive::Child &NewArchiveIterator::getOld() const {
-  assert(!IsNewMember);
-  return OldMember;
-}
-
-StringRef NewArchiveIterator::getNew() const {
-  assert(IsNewMember);
-  return Name;
+NewArchiveMember::NewArchiveMember(MemoryBufferRef BufRef)
+    : Buf(MemoryBuffer::getMemBuffer(BufRef, false)) {}
+
+Expected<NewArchiveMember>
+NewArchiveMember::getOldMember(const object::Archive::Child &OldMember,
+                               bool Deterministic) {
+  ErrorOr<llvm::MemoryBufferRef> BufOrErr = OldMember.getMemoryBufferRef();
+  if (!BufOrErr)
+    return errorCodeToError(BufOrErr.getError());
+
+  NewArchiveMember M;
+  M.Buf = MemoryBuffer::getMemBuffer(*BufOrErr, false);
+  if (!Deterministic) {
+    M.ModTime = OldMember.getLastModified();
+    M.UID = OldMember.getUID();
+    M.GID = OldMember.getGID();
+    M.Perms = OldMember.getAccessMode();
+  }
+  return std::move(M);
 }
 
-llvm::ErrorOr<int>
-NewArchiveIterator::getFD(sys::fs::file_status &NewStatus) const {
-  assert(IsNewMember);
-  int NewFD;
-  if (auto EC = sys::fs::openFileForRead(Name, NewFD))
-    return EC;
-  assert(NewFD != -1);
+Expected<NewArchiveMember> NewArchiveMember::getFile(StringRef FileName,
+                                                     bool Deterministic) {
+  sys::fs::file_status Status;
+  int FD;
+  if (auto EC = sys::fs::openFileForRead(FileName, FD))
+    return errorCodeToError(EC);
+  assert(FD != -1);
 
-  if (auto EC = sys::fs::status(NewFD, NewStatus))
-    return EC;
+  if (auto EC = sys::fs::status(FD, Status))
+    return errorCodeToError(EC);
 
   // Opening a directory doesn't make sense. Let it fail.
   // Linux cannot open directories with open(2), although
   // cygwin and *bsd can.
-  if (NewStatus.type() == sys::fs::file_type::directory_file)
-    return make_error_code(errc::is_a_directory);
-
-  return NewFD;
+  if (Status.type() == sys::fs::file_type::directory_file)
+    return errorCodeToError(make_error_code(errc::is_a_directory));
+
+  ErrorOr<std::unique_ptr<MemoryBuffer>> MemberBufferOrErr =
+      MemoryBuffer::getOpenFile(FD, FileName, Status.getSize(), false);
+  if (!MemberBufferOrErr)
+    return errorCodeToError(MemberBufferOrErr.getError());
+
+  if (close(FD) != 0)
+    return errorCodeToError(std::error_code(errno, std::generic_category()));
+
+  NewArchiveMember M;
+  M.Buf = std::move(*MemberBufferOrErr);
+  if (!Deterministic) {
+    M.ModTime = Status.getLastModificationTime();
+    M.UID = Status.getUser();
+    M.GID = Status.getGroup();
+    M.Perms = Status.permissions();
+  }
+  return std::move(M);
 }
 
 template <typename T>
@@ -178,12 +194,13 @@ static std::string computeRelativePath(StringRef From, StringRef To) {
 }
 
 static void writeStringTable(raw_fd_ostream &Out, StringRef ArcName,
-                             ArrayRef<NewArchiveIterator> Members,
+                             ArrayRef<NewArchiveMember> Members,
                              std::vector<unsigned> &StringMapIndexes,
                              bool Thin) {
   unsigned StartOffset = 0;
-  for (const NewArchiveIterator &I : Members) {
-    StringRef Name = sys::path::filename(I.getName());
+  for (const NewArchiveMember &M : Members) {
+    StringRef Path = M.Buf->getBufferIdentifier();
+    StringRef Name = sys::path::filename(Path);
     if (!useStringTable(Thin, Name))
       continue;
     if (StartOffset == 0) {
@@ -194,7 +211,7 @@ static void writeStringTable(raw_fd_ostream &Out, StringRef ArcName,
     StringMapIndexes.push_back(Out.tell() - StartOffset);
 
     if (Thin)
-      Out << computeRelativePath(ArcName, I.getName());
+      Out << computeRelativePath(ArcName, Path);
     else
       Out << Name;
 
@@ -221,8 +238,7 @@ static sys::TimeValue now(bool Deterministic) {
 // Returns the offset of the first reference to a member offset.
 static ErrorOr<unsigned>
 writeSymbolTable(raw_fd_ostream &Out, object::Archive::Kind Kind,
-                 ArrayRef<NewArchiveIterator> Members,
-                 ArrayRef<MemoryBufferRef> Buffers,
+                 ArrayRef<NewArchiveMember> Members,
                  std::vector<unsigned> &MemberOffsetRefs, bool Deterministic) {
   unsigned HeaderStartOffset = 0;
   unsigned BodyStartOffset = 0;
@@ -230,7 +246,7 @@ writeSymbolTable(raw_fd_ostream &Out, object::Archive::Kind Kind,
   raw_svector_ostream NameOS(NameBuf);
   LLVMContext Context;
   for (unsigned MemberNum = 0, N = Members.size(); MemberNum < N; ++MemberNum) {
-    MemoryBufferRef MemberBuffer = Buffers[MemberNum];
+    MemoryBufferRef MemberBuffer = Members[MemberNum].Buf->getMemBufferRef();
     Expected<std::unique_ptr<object::SymbolicFile>> ObjOrErr =
         object::SymbolicFile::createSymbolicFile(
             MemberBuffer, sys::fs::file_magic::unknown, &Context);
@@ -305,7 +321,7 @@ writeSymbolTable(raw_fd_ostream &Out, object::Archive::Kind Kind,
 
 std::pair<StringRef, std::error_code>
 llvm::writeArchive(StringRef ArcName,
-                   std::vector<NewArchiveIterator> &NewMembers,
+                   std::vector<NewArchiveMember> &NewMembers,
                    bool WriteSymtab, object::Archive::Kind Kind,
                    bool Deterministic, bool Thin,
                    std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
@@ -330,43 +346,10 @@ llvm::writeArchive(StringRef ArcName,
   std::vector<MemoryBufferRef> Members;
   std::vector<sys::fs::file_status> NewMemberStatus;
 
-  for (NewArchiveIterator &Member : NewMembers) {
-    MemoryBufferRef MemberRef;
-
-    if (Member.isNewMember()) {
-      StringRef Filename = Member.getNew();
-      NewMemberStatus.resize(NewMemberStatus.size() + 1);
-      sys::fs::file_status &Status = NewMemberStatus.back();
-      ErrorOr<int> FD = Member.getFD(Status);
-      if (auto EC = FD.getError())
-        return std::make_pair(Filename, EC);
-      ErrorOr<std::unique_ptr<MemoryBuffer>> MemberBufferOrErr =
-          MemoryBuffer::getOpenFile(FD.get(), Filename, Status.getSize(),
-                                    false);
-      if (auto EC = MemberBufferOrErr.getError())
-        return std::make_pair(Filename, EC);
-      if (close(FD.get()) != 0)
-        return std::make_pair(Filename,
-                              std::error_code(errno, std::generic_category()));
-      Buffers.push_back(std::move(MemberBufferOrErr.get()));
-      MemberRef = Buffers.back()->getMemBufferRef();
-    } else {
-      const object::Archive::Child &OldMember = Member.getOld();
-      assert((!Thin || OldMember.getParent()->isThin()) &&
-             "Thin archives cannot refers to member of other archives");
-      ErrorOr<MemoryBufferRef> MemberBufferOrErr =
-          OldMember.getMemoryBufferRef();
-      if (auto EC = MemberBufferOrErr.getError())
-        return std::make_pair("", EC);
-      MemberRef = MemberBufferOrErr.get();
-    }
-    Members.push_back(MemberRef);
-  }
-
   unsigned MemberReferenceOffset = 0;
   if (WriteSymtab) {
     ErrorOr<unsigned> MemberReferenceOffsetOrErr = writeSymbolTable(
-        Out, Kind, NewMembers, Members, MemberOffsetRefs, Deterministic);
+        Out, Kind, NewMembers, MemberOffsetRefs, Deterministic);
     if (auto EC = MemberReferenceOffsetOrErr.getError())
       return std::make_pair(ArcName, EC);
     MemberReferenceOffset = MemberReferenceOffsetOrErr.get();
@@ -376,55 +359,18 @@ llvm::writeArchive(StringRef ArcName,
   if (Kind != object::Archive::K_BSD)
     writeStringTable(Out, ArcName, NewMembers, StringMapIndexes, Thin);
 
-  unsigned MemberNum = 0;
-  unsigned NewMemberNum = 0;
   std::vector<unsigned>::iterator StringMapIndexIter = StringMapIndexes.begin();
   std::vector<unsigned> MemberOffset;
-  for (const NewArchiveIterator &I : NewMembers) {
-    MemoryBufferRef File = Members[MemberNum++];
+  for (const NewArchiveMember &M : NewMembers) {
+    MemoryBufferRef File = M.Buf->getMemBufferRef();
 
     unsigned Pos = Out.tell();
     MemberOffset.push_back(Pos);
 
-    sys::TimeValue ModTime;
-    unsigned UID;
-    unsigned GID;
-    unsigned Perms;
-    if (Deterministic) {
-      ModTime.fromEpochTime(0);
-      UID = 0;
-      GID = 0;
-      Perms = 0644;
-    } else if (I.isNewMember()) {
-      const sys::fs::file_status &Status = NewMemberStatus[NewMemberNum];
-      ModTime = Status.getLastModificationTime();
-      UID = Status.getUser();
-      GID = Status.getGroup();
-      Perms = Status.permissions();
-    } else {
-      const object::Archive::Child &OldMember = I.getOld();
-      ModTime = OldMember.getLastModified();
-      UID = OldMember.getUID();
-      GID = OldMember.getGID();
-      Perms = OldMember.getAccessMode();
-    }
-
-    if (I.isNewMember()) {
-      StringRef FileName = I.getNew();
-      const sys::fs::file_status &Status = NewMemberStatus[NewMemberNum++];
-      printMemberHeader(Out, Kind, Thin, sys::path::filename(FileName),
-                        StringMapIndexIter, ModTime, UID, GID, Perms,
-                        Status.getSize());
-    } else {
-      const object::Archive::Child &OldMember = I.getOld();
-      ErrorOr<uint32_t> Size = OldMember.getSize();
-      if (std::error_code EC = Size.getError())
-        return std::make_pair("", EC);
-      StringRef FileName = I.getName();
-      printMemberHeader(Out, Kind, Thin, sys::path::filename(FileName),
-                        StringMapIndexIter, ModTime, UID, GID, Perms,
-                        Size.get());
-    }
+    printMemberHeader(Out, Kind, Thin,
+                      sys::path::filename(M.Buf->getBufferIdentifier()),
+                      StringMapIndexIter, M.ModTime, M.UID, M.GID, M.Perms,
+                      M.Buf->getBufferSize());
 
     if (!Thin)
       Out << File.getBuffer();