contrib/llvm-project/llvm/tools/llvm-objcopy/MachO/Object.cpp

   1 #include "Object.h"
   2 #include "../llvm-objcopy.h"
   3
   4 namespace llvm {
   5 namespace objcopy {
   6 namespace macho {
   7
   8 const SymbolEntry *SymbolTable::getSymbolByIndex(uint32_t Index) const {
   9   assert(Index < Symbols.size() && "invalid symbol index");
  10   return Symbols[Index].get();
  11 }
  12
  13 SymbolEntry *SymbolTable::getSymbolByIndex(uint32_t Index) {
  14   return const_cast<SymbolEntry *>(
  15       static_cast<const SymbolTable *>(this)->getSymbolByIndex(Index));
  16 }
  17
  18 void SymbolTable::removeSymbols(
  19     function_ref<bool(const std::unique_ptr<SymbolEntry> &)> ToRemove) {
  20   Symbols.erase(
  21       std::remove_if(std::begin(Symbols), std::end(Symbols), ToRemove),
  22       std::end(Symbols));
  23 }
  24
  25 void Object::removeSections(function_ref<bool(const Section &)> ToRemove) {
  26   for (LoadCommand &LC : LoadCommands)
  27     LC.Sections.erase(std::remove_if(std::begin(LC.Sections),
  28                                      std::end(LC.Sections), ToRemove),
  29                       std::end(LC.Sections));
  30 }
  31
  32 void Object::addLoadCommand(LoadCommand LC) {
  33   LoadCommands.push_back(std::move(LC));
  34 }
  35
  36 template <typename SegmentType>
  37 static void constructSegment(SegmentType &Seg,
  38                              llvm::MachO::LoadCommandType CmdType,
  39                              StringRef SegName) {
  40   assert(SegName.size() <= sizeof(Seg.segname) && "too long segment name");
  41   memset(&Seg, 0, sizeof(SegmentType));
  42   Seg.cmd = CmdType;
  43   strncpy(Seg.segname, SegName.data(), SegName.size());
  44 }
  45
  46 LoadCommand &Object::addSegment(StringRef SegName) {
  47   LoadCommand LC;
  48   if (is64Bit())
  49     constructSegment(LC.MachOLoadCommand.segment_command_64_data,
  50                      MachO::LC_SEGMENT_64, SegName);
  51   else
  52     constructSegment(LC.MachOLoadCommand.segment_command_data,
  53                      MachO::LC_SEGMENT, SegName);
  54
  55   LoadCommands.push_back(LC);
  56   return LoadCommands.back();
  57 }
  58
  59 /// Extracts a segment name from a string which is possibly non-null-terminated.
  60 static StringRef extractSegmentName(const char *SegName) {
  61   return StringRef(SegName,
  62                    strnlen(SegName, sizeof(MachO::segment_command::segname)));
  63 }
  64
  65 Optional<StringRef> LoadCommand::getSegmentName() const {
  66   const MachO::macho_load_command &MLC = MachOLoadCommand;
  67   switch (MLC.load_command_data.cmd) {
  68   case MachO::LC_SEGMENT:
  69     return extractSegmentName(MLC.segment_command_data.segname);
  70   case MachO::LC_SEGMENT_64:
  71     return extractSegmentName(MLC.segment_command_64_data.segname);
  72   default:
  73     return None;
  74   }
  75 }
  76
  77 } // end namespace macho
  78 } // end namespace objcopy
  79 } // end namespace llvm