Method LoadElfFile

Source/Tools/FEXLoader/ELFCodeLoader.h:124–204

  }

  std::optional<uintptr_t> LoadElfFile(ELFParser& Elf, uintptr_t* BrkBase, FEX::HLE::SyscallHandler* const Handler, uint64_t LoadHint = 0) {

    uintptr_t LoadBase = 0;
    uintptr_t BrkLoadBase = 0;
    const bool DynELF = Elf.ehdr.e_type == ET_DYN;
    const bool NeedsLateBRKMap = BrkBase && !DynELF;

    if (DynELF) {
      // Allocate a base address plus BRK padding.
      auto TotalSize = CalculateDYNELFSize(Elf.phdrs) + (BrkBase ? BRK_SIZE : 0);
      LoadBase =
        (uintptr_t)Handler->GuestMmap(nullptr, reinterpret_cast<void*>(LoadHint), TotalSize, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
      if (FEX::HLE::HasSyscallError(LoadBase)) {
        return {};
      }

      // fprintf(stderr, "elf %d: %lx-%lx\n", Elf.fd, LoadBase, LoadBase + TotalSize);
      if (BrkBase) {
        BrkLoadBase = LoadBase + (TotalSize - BRK_SIZE);
      }
    }

    for (const auto& Header : Elf.phdrs) {
      if (Header.p_type != PT_LOAD) {
        continue;
      }

      int MapProt = MapFlags(Header);
      int MapType = MAP_PRIVATE | MAP_DENYWRITE | MAP_FIXED;

      if (!MapFile(Elf, LoadBase, Header, MapProt, MapType, Handler)) {
        return {};
      }

      if (Header.p_memsz > Header.p_filesz) {
        // clear bss
        auto BSSStart = LoadBase + Header.p_vaddr + Header.p_filesz;
        auto BSSPageStart = PAGE_ALIGN(BSSStart);
        auto BSSPageEnd = PAGE_ALIGN(LoadBase + Header.p_vaddr + Header.p_memsz);

        // Only clear padding bytes if the section is writable
        if (Header.p_flags & PF_W) {
          memset((void*)BSSStart, 0, BSSPageStart - BSSStart);
        }

        if (BSSPageStart != BSSPageEnd) {
          auto bss = Handler->GuestMmap(nullptr, (void*)BSSPageStart, BSSPageEnd - BSSPageStart, MapProt, MapType | MAP_ANONYMOUS, -1, 0);
          if (FEX::HLE::HasSyscallError(bss)) {
            LogMan::Msg::EFmt("Failed to allocate BSS @ {}, {}\n", fmt::ptr(bss), errno);
            return {};
          }
        }
      }

      if (NeedsLateBRKMap) {
        // Keep track of highest address for BRK in the case of non-dynamic ELF files.
        auto memend = LoadBase + Header.p_vaddr + Header.p_memsz;