[llvm] r224307 - Start adding thin archive support.

[Rafael Espindola]

Author: rafael
Date: Mon Dec 15 19:43:41 2014
New Revision: 224307

URL: http://llvm.org/viewvc/llvm-project?rev=224307&view=rev
Log:
Start adding thin archive support.

This is just sufficient for 'ar t' to work.

Added:
    llvm/trunk/test/Object/Inputs/thin.a
Modified:
    llvm/trunk/include/llvm/Object/Archive.h
    llvm/trunk/lib/Object/Archive.cpp
    llvm/trunk/test/Object/archive-toc.test

Modified: llvm/trunk/include/llvm/Object/Archive.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/Archive.h?rev=224307&r1=224306&r2=224307&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/Archive.h (original)
+++ llvm/trunk/include/llvm/Object/Archive.h Mon Dec 15 19:43:41 2014
@@ -84,7 +84,7 @@ public:
       return getHeader()->getAccessMode();
     }
     /// \return the size of the archive member without the header or padding.
-    uint64_t getSize() const { return Data.size() - StartOfFile; }
+    uint64_t getSize() const;
 
     StringRef getBuffer() const {
       return StringRef(Data.data() + StartOfFile, getSize());
@@ -173,9 +173,7 @@ public:
     K_COFF
   };
 
-  Kind kind() const { 
-    return Format;
-  }
+  Kind kind() const { return (Kind)Format; }
 
   child_iterator child_begin(bool SkipInternal = true) const;
   child_iterator child_end() const;
@@ -201,7 +199,8 @@ private:
   child_iterator SymbolTable;
   child_iterator StringTable;
   child_iterator FirstRegular;
-  Kind Format;
+  unsigned Format : 2;
+  unsigned IsThin : 1;
 };
 
 }

Modified: llvm/trunk/lib/Object/Archive.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/Archive.cpp?rev=224307&r1=224306&r2=224307&view=diff
==============================================================================
--- llvm/trunk/lib/Object/Archive.cpp (original)
+++ llvm/trunk/lib/Object/Archive.cpp Mon Dec 15 19:43:41 2014
@@ -22,6 +22,7 @@ using namespace llvm;
 using namespace object;
 
 static const char *const Magic = "!<arch>\n";
+static const char *const ThinMagic = "!<thin>\n";
 
 void Archive::anchor() { }
 
@@ -86,7 +87,10 @@ Archive::Child::Child(const Archive *Par
 
   const ArchiveMemberHeader *Header =
       reinterpret_cast<const ArchiveMemberHeader *>(Start);
-  Data = StringRef(Start, sizeof(ArchiveMemberHeader) + Header->getSize());
+  uint64_t Size = sizeof(ArchiveMemberHeader);
+  if (!Parent->IsThin || Header->getName() == "/" || Header->getName() == "//")
+    Size += Header->getSize();
+  Data = StringRef(Start, Size);
 
   // Setup StartOfFile and PaddingBytes.
   StartOfFile = sizeof(ArchiveMemberHeader);
@@ -100,6 +104,12 @@ Archive::Child::Child(const Archive *Par
   }
 }
 
+uint64_t Archive::Child::getSize() const {
+  if (Parent->IsThin)
+    return getHeader()->getSize();
+  return Data.size() - StartOfFile;
+}
+
 Archive::Child Archive::Child::getNext() const {
   size_t SpaceToSkip = Data.size();
   // If it's odd, add 1 to make it even.
@@ -186,9 +196,13 @@ ErrorOr<std::unique_ptr<Archive>> Archiv
 
 Archive::Archive(MemoryBufferRef Source, std::error_code &ec)
     : Binary(Binary::ID_Archive, Source), SymbolTable(child_end()) {
+  StringRef Buffer = Data.getBuffer();
   // Check for sufficient magic.
-  if (Data.getBufferSize() < 8 ||
-      StringRef(Data.getBufferStart(), 8) != Magic) {
+  if (Buffer.startswith(ThinMagic)) {
+    IsThin = true;
+  } else if (Buffer.startswith(Magic)) {
+    IsThin = false;
+  } else {
     ec = object_error::invalid_file_type;
     return;
   }

Added: llvm/trunk/test/Object/Inputs/thin.a
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/thin.a?rev=224307&view=auto
==============================================================================
Binary files llvm/trunk/test/Object/Inputs/thin.a (added) and llvm/trunk/test/Object/Inputs/thin.a Mon Dec 15 19:43:41 2014 differ

Modified: llvm/trunk/test/Object/archive-toc.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/archive-toc.test?rev=224307&r1=224306&r2=224307&view=diff
==============================================================================
--- llvm/trunk/test/Object/archive-toc.test (original)
+++ llvm/trunk/test/Object/archive-toc.test Mon Dec 15 19:43:41 2014
@@ -26,3 +26,11 @@ CHECK:      rw-r--r-- 1002/102      8 20
 CHECK-NEXT: rw-r--r-- 1002/102      7 2004-11-19 03:24:02.000000000 oddlen
 CHECK-NEXT: rwxr-xr-x 1002/102   1465 2004-11-19 03:24:02.000000000 very_long_bytecode_file_name.bc
 CHECK-NEXT: rw-r--r-- 1002/102   2280 2004-11-19 03:24:02.000000000 IsNAN.o
+
+Test reading a thin archive created by gnu ar
+RUN: env TZ=GMT llvm-ar tv %p/Inputs/thin.a | FileCheck %s --check-prefix=THIN -strict-whitespace
+
+THIN:      rw-r--r-- 1000/1000      8 2014-12-16 00:56:27.000000000 evenlen
+THIN-NEXT: rw-r--r-- 1000/1000      7 2014-12-16 00:56:27.000000000 oddlen
+THIN-NEXT: rwxr-xr-x 1000/1000   1465 2014-12-16 00:56:27.000000000 very_long_bytecode_file_name.bc
+THIN-NEXT: rw-r--r-- 1000/1000   2280 2014-12-16 00:56:27.000000000 IsNAN.o