[llvm-objcopy] Add support for .dynamic, .dynsym, and .dynstr

This change adds support for sections involved in dynamic loading such
as SHT_DYNAMIC, SHT_DYNSYM, and allocated string tables.

The two added binaries used for tests can be downloaded [[
https://drive.google.com/file/d/0B3gtIAmiMwZXOXE3T0RobFg4ZTg/view?usp=sharing
| here ]] and [[
https://drive.google.com/file/d/0B3gtIAmiMwZXTFJSQUJZMGxNSXc/view?usp=sharing
| here ]]

Differential Revision: https://reviews.llvm.org/D36560

llvm-svn: 313663

1 files changed, 34 insertions, 0 deletions

diff --git a/llvm/tools/llvm-objcopy/Object.h b/llvm/tools/llvm-objcopy/Object.h
index 1b7127e86da..7a6f0132a0e 100644
--- a/llvm/tools/llvm-objcopy/Object.h
+++ b/llvm/tools/llvm-objcopy/Object.h
@@ -194,6 +194,34 @@ public:
   }
 };
 
+class SectionWithStrTab : public Section {
+private:
+  StringTableSection *StrTab;
+
+public:
+  SectionWithStrTab(llvm::ArrayRef<uint8_t> Data) : Section(Data) {}
+  void setStrTab(StringTableSection *StringTable) { StrTab = StringTable; }
+  void finalize() override;
+  static bool classof(const SectionBase *S);
+};
+
+class DynamicSymbolTableSection : public SectionWithStrTab {
+public:
+  DynamicSymbolTableSection(llvm::ArrayRef<uint8_t> Data)
+      : SectionWithStrTab(Data) {}
+  static bool classof(const SectionBase *S) {
+    return S->Type == llvm::ELF::SHT_DYNSYM;
+  }
+};
+
+class DynamicSection : public SectionWithStrTab {
+public:
+  DynamicSection(llvm::ArrayRef<uint8_t> Data) : SectionWithStrTab(Data) {}
+  static bool classof(const SectionBase *S) {
+    return S->Type == llvm::ELF::SHT_DYNAMIC;
+  }
+};
+
 template <class ELFT> class Object {
 private:
   typedef std::unique_ptr<SectionBase> SecPtr;
@@ -210,6 +238,12 @@ private:
   void readProgramHeaders(const llvm::object::ELFFile<ELFT> &ElfFile);
   void readSectionHeaders(const llvm::object::ELFFile<ELFT> &ElfFile);
 
+  SectionBase *getSection(uint16_t Index, llvm::Twine ErrMsg);
+
+  template <class T>
+  T *getSectionOfType(uint16_t Index, llvm::Twine IndexErrMsg,
+                      llvm::Twine TypeErrMsg);
+
 protected:
   StringTableSection *SectionNames;
   SymbolTableSection *SymbolTable;