1 files changed, 81 insertions, 36 deletions
diff --git a/contrib/llvm/lib/Object/ArchiveWriter.cpp b/contrib/llvm/lib/Object/ArchiveWriter.cpp
index a40901c..c7343fd 100644
--- a/contrib/llvm/lib/Object/ArchiveWriter.cpp
+++ b/contrib/llvm/lib/Object/ArchiveWriter.cpp
@@ -34,32 +34,32 @@
 
 using namespace llvm;
 
-NewArchiveIterator::NewArchiveIterator(object::Archive::child_iterator I,
+NewArchiveIterator::NewArchiveIterator(const object::Archive::Child &OldMember,
                                        StringRef Name)
-    : IsNewMember(false), Name(Name), OldI(I) {}
+    : IsNewMember(false), Name(Name), OldMember(OldMember) {}
 
-NewArchiveIterator::NewArchiveIterator(StringRef NewFilename, StringRef Name)
-    : IsNewMember(true), Name(Name), NewFilename(NewFilename) {}
+NewArchiveIterator::NewArchiveIterator(StringRef FileName)
+    : IsNewMember(true), Name(FileName), OldMember(nullptr, nullptr, nullptr) {}
 
 StringRef NewArchiveIterator::getName() const { return Name; }
 
 bool NewArchiveIterator::isNewMember() const { return IsNewMember; }
 
-object::Archive::child_iterator NewArchiveIterator::getOld() const {
+const object::Archive::Child &NewArchiveIterator::getOld() const {
   assert(!IsNewMember);
-  return OldI;
+  return OldMember;
 }
 
 StringRef NewArchiveIterator::getNew() const {
   assert(IsNewMember);
-  return NewFilename;
+  return Name;
 }
 
 llvm::ErrorOr<int>
 NewArchiveIterator::getFD(sys::fs::file_status &NewStatus) const {
   assert(IsNewMember);
   int NewFD;
-  if (auto EC = sys::fs::openFileForRead(NewFilename, NewFD))
+  if (auto EC = sys::fs::openFileForRead(Name, NewFD))
     return EC;
   assert(NewFD != -1);
 
@@ -77,7 +77,7 @@ NewArchiveIterator::getFD(sys::fs::file_status &NewStatus) const {
 
 template <typename T>
 static void printWithSpacePadding(raw_fd_ostream &OS, T Data, unsigned Size,
-				  bool MayTruncate = false) {
+                                  bool MayTruncate = false) {
   uint64_t OldPos = OS.tell();
   OS << Data;
   unsigned SizeSoFar = OS.tell() - OldPos;
@@ -135,30 +135,56 @@ static void printBSDMemberHeader(raw_fd_ostream &Out, StringRef Name,
     Out.write(uint8_t(0));
 }
 
+static bool useStringTable(bool Thin, StringRef Name) {
+  return Thin || Name.size() >= 16;
+}
+
 static void
-printMemberHeader(raw_fd_ostream &Out, object::Archive::Kind Kind,
+printMemberHeader(raw_fd_ostream &Out, object::Archive::Kind Kind, bool Thin,
                   StringRef Name,
                   std::vector<unsigned>::iterator &StringMapIndexIter,
                   const sys::TimeValue &ModTime, unsigned UID, unsigned GID,
                   unsigned Perms, unsigned Size) {
   if (Kind == object::Archive::K_BSD)
     return printBSDMemberHeader(Out, Name, ModTime, UID, GID, Perms, Size);
-  if (Name.size() < 16)
+  if (!useStringTable(Thin, Name))
     return printGNUSmallMemberHeader(Out, Name, ModTime, UID, GID, Perms, Size);
   Out << '/';
   printWithSpacePadding(Out, *StringMapIndexIter++, 15);
   printRestOfMemberHeader(Out, ModTime, UID, GID, Perms, Size);
 }
 
-static void writeStringTable(raw_fd_ostream &Out,
+// Compute the relative path from From to To.
+static std::string computeRelativePath(StringRef From, StringRef To) {
+  if (sys::path::is_absolute(From) || sys::path::is_absolute(To))
+    return To;
+
+  StringRef DirFrom = sys::path::parent_path(From);
+  auto FromI = sys::path::begin(DirFrom);
+  auto ToI = sys::path::begin(To);
+  while (*FromI == *ToI) {
+    ++FromI;
+    ++ToI;
+  }
+
+  SmallString<128> Relative;
+  for (auto FromE = sys::path::end(DirFrom); FromI != FromE; ++FromI)
+    sys::path::append(Relative, "..");
+
+  for (auto ToE = sys::path::end(To); ToI != ToE; ++ToI)
+    sys::path::append(Relative, *ToI);
+
+  return Relative.str();
+}
+
+static void writeStringTable(raw_fd_ostream &Out, StringRef ArcName,
                              ArrayRef<NewArchiveIterator> Members,
-                             std::vector<unsigned> &StringMapIndexes) {
+                             std::vector<unsigned> &StringMapIndexes,
+                             bool Thin) {
   unsigned StartOffset = 0;
-  for (ArrayRef<NewArchiveIterator>::iterator I = Members.begin(),
-                                              E = Members.end();
-       I != E; ++I) {
-    StringRef Name = I->getName();
-    if (Name.size() < 16)
+  for (const NewArchiveIterator &I : Members) {
+    StringRef Name = sys::path::filename(I.getName());
+    if (!useStringTable(Thin, Name))
       continue;
     if (StartOffset == 0) {
       printWithSpacePadding(Out, "//", 58);
@@ -166,7 +192,13 @@ static void writeStringTable(raw_fd_ostream &Out,
       StartOffset = Out.tell();
     }
     StringMapIndexes.push_back(Out.tell() - StartOffset);
-    Out << Name << "/\n";
+
+    if (Thin)
+      Out << computeRelativePath(ArcName, I.getName());
+    else
+      Out << Name;
+
+    Out << "/\n";
   }
   if (StartOffset == 0)
     return;
@@ -268,9 +300,11 @@ writeSymbolTable(raw_fd_ostream &Out, object::Archive::Kind Kind,
   return BodyStartOffset + 4;
 }
 
-std::pair<StringRef, std::error_code> llvm::writeArchive(
-    StringRef ArcName, std::vector<NewArchiveIterator> &NewMembers,
-    bool WriteSymtab, object::Archive::Kind Kind, bool Deterministic) {
+std::pair<StringRef, std::error_code>
+llvm::writeArchive(StringRef ArcName,
+                   std::vector<NewArchiveIterator> &NewMembers,
+                   bool WriteSymtab, object::Archive::Kind Kind,
+                   bool Deterministic, bool Thin) {
   SmallString<128> TmpArchive;
   int TmpArchiveFD;
   if (auto EC = sys::fs::createUniqueFile(ArcName + ".temp-archive-%%%%%%%.a",
@@ -279,7 +313,10 @@ std::pair<StringRef, std::error_code> llvm::writeArchive(
 
   tool_output_file Output(TmpArchive, TmpArchiveFD);
   raw_fd_ostream &Out = Output.os();
-  Out << "!<arch>\n";
+  if (Thin)
+    Out << "!<thin>\n";
+  else
+    Out << "!<arch>\n";
 
   std::vector<unsigned> MemberOffsetRefs;
 
@@ -309,9 +346,11 @@ std::pair<StringRef, std::error_code> llvm::writeArchive(
       Buffers.push_back(std::move(MemberBufferOrErr.get()));
       MemberRef = Buffers.back()->getMemBufferRef();
     } else {
-      object::Archive::child_iterator OldMember = Member.getOld();
+      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();
+          OldMember.getMemoryBufferRef();
       if (auto EC = MemberBufferOrErr.getError())
         return std::make_pair("", EC);
       MemberRef = MemberBufferOrErr.get();
@@ -330,7 +369,7 @@ std::pair<StringRef, std::error_code> llvm::writeArchive(
 
   std::vector<unsigned> StringMapIndexes;
   if (Kind != object::Archive::K_BSD)
-    writeStringTable(Out, NewMembers, StringMapIndexes);
+    writeStringTable(Out, ArcName, NewMembers, StringMapIndexes, Thin);
 
   unsigned MemberNum = 0;
   unsigned NewMemberNum = 0;
@@ -358,26 +397,32 @@ std::pair<StringRef, std::error_code> llvm::writeArchive(
       GID = Status.getGroup();
       Perms = Status.permissions();
     } else {
-      object::Archive::child_iterator OldMember = I.getOld();
-      ModTime = OldMember->getLastModified();
-      UID = OldMember->getUID();
-      GID = OldMember->getGID();
-      Perms = OldMember->getAccessMode();
+      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, sys::path::filename(FileName),
+      printMemberHeader(Out, Kind, Thin, sys::path::filename(FileName),
                         StringMapIndexIter, ModTime, UID, GID, Perms,
                         Status.getSize());
     } else {
-      object::Archive::child_iterator OldMember = I.getOld();
-      printMemberHeader(Out, Kind, I.getName(), StringMapIndexIter, ModTime,
-                        UID, GID, Perms, OldMember->getSize());
+      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());
     }
 
-    Out << File.getBuffer();
+    if (!Thin)
+      Out << File.getBuffer();
 
     if (Out.tell() % 2)
       Out << '\n';