Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- Archive.h - ar archive file format -----------------------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

// This file declares the ar archive file format class.

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_OBJECT_ARCHIVE_H

#define LLVM_OBJECT_ARCHIVE_H

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/fallible_iterator.h"

#include "llvm/ADT/iterator_range.h"

#include "llvm/Object/Binary.h"

#include "llvm/Support/Chrono.h"

#include "llvm/Support/Error.h"

#include "llvm/Support/FileSystem.h"

#include "llvm/Support/MemoryBuffer.h"

#include <cassert>

#include <cstdint>

#include <memory>

#include <string>

#include <vector>

namespace llvm {

namespace object {

const char ArchiveMagic[] = "!<arch>\n";

const char ThinArchiveMagic[] = "!<thin>\n";

const char BigArchiveMagic[] = "<bigaf>\n";

class Archive;

class AbstractArchiveMemberHeader {

protected:

  AbstractArchiveMemberHeader(const Archive *Parent) : Parent(Parent){};

public:

  friend class Archive;

  virtual std::unique_ptr<AbstractArchiveMemberHeader> clone() const = 0;

  virtual ~AbstractArchiveMemberHeader() = default;

  /// Get the name without looking up long names.

  virtual Expected<StringRef> getRawName() const = 0;

  virtual StringRef getRawAccessMode() const = 0;

  virtual StringRef getRawLastModified() const = 0;

  virtual StringRef getRawUID() const = 0;

  virtual StringRef getRawGID() const = 0;

  /// Get the name looking up long names.

  virtual Expected<StringRef> getName(uint64_t Size) const = 0;

  virtual Expected<uint64_t> getSize() const = 0;

  virtual uint64_t getOffset() const = 0;

  /// Get next file member location.

  virtual Expected<const char *> getNextChildLoc() const = 0;

  virtual Expected<bool> isThin() const = 0;

  Expected<sys::fs::perms> getAccessMode() const;

  Expected<sys::TimePoint<std::chrono::seconds>> getLastModified() const;

  Expected<unsigned> getUID() const;

  Expected<unsigned> getGID() const;

  /// Returns the size in bytes of the format-defined member header of the

  /// concrete archive type.

  virtual uint64_t getSizeOf() const = 0;

  const Archive *Parent;

};

template <typename T>

class CommonArchiveMemberHeader : public AbstractArchiveMemberHeader {

public:

  CommonArchiveMemberHeader(const Archive *Parent, const T *RawHeaderPtr)

      : AbstractArchiveMemberHeader(Parent), ArMemHdr(RawHeaderPtr){};

  StringRef getRawAccessMode() const override;

  StringRef getRawLastModified() const override;

  StringRef getRawUID() const override;

  StringRef getRawGID() const override;

  uint64_t getOffset() const override;

  uint64_t getSizeOf() const override { return sizeof(T); }

  T const *ArMemHdr;

};

struct UnixArMemHdrType {

  char Name[16];

  char LastModified[12];

  char UID[6];

  char GID[6];

  char AccessMode[8];

  char Size[10]; ///< Size of data, not including header or padding.

  char Terminator[2];

};

class ArchiveMemberHeader : public CommonArchiveMemberHeader<UnixArMemHdrType> {

public:

  ArchiveMemberHeader(const Archive *Parent, const char *RawHeaderPtr,

                      uint64_t Size, Error *Err);

  std::unique_ptr<AbstractArchiveMemberHeader> clone() const override {

    return std::make_unique<ArchiveMemberHeader>(*this);

  }

  Expected<StringRef> getRawName() const override;

  Expected<StringRef> getName(uint64_t Size) const override;

  Expected<uint64_t> getSize() const override;

  Expected<const char *> getNextChildLoc() const override;

  Expected<bool> isThin() const override;

};

// File Member Header

struct BigArMemHdrType {

  char Size[20];       // File member size in decimal

  char NextOffset[20]; // Next member offset in decimal

  char PrevOffset[20]; // Previous member offset in decimal

  char LastModified[12];

  char UID[12];

  char GID[12];

  char AccessMode[12];

  char NameLen[4]; // File member name length in decimal

  union {

    char Name[2]; // Start of member name

    char Terminator[2];

  };

};

// Define file member header of AIX big archive.

class BigArchiveMemberHeader

    : public CommonArchiveMemberHeader<BigArMemHdrType> {

public:

  BigArchiveMemberHeader(Archive const *Parent, const char *RawHeaderPtr,

                         uint64_t Size, Error *Err);

  std::unique_ptr<AbstractArchiveMemberHeader> clone() const override {

    return std::make_unique<BigArchiveMemberHeader>(*this);

  }

  Expected<StringRef> getRawName() const override;

  Expected<uint64_t> getRawNameSize() const;

  Expected<StringRef> getName(uint64_t Size) const override;

  Expected<uint64_t> getSize() const override;

  Expected<const char *> getNextChildLoc() const override;

  Expected<uint64_t> getNextOffset() const;

  Expected<bool> isThin() const override { return false; }

};

class Archive : public Binary {

  virtual void anchor();

public:

  class Child {

    friend Archive;

    friend AbstractArchiveMemberHeader;

    const Archive *Parent;

    std::unique_ptr<AbstractArchiveMemberHeader> Header;

    /// Includes header but not padding byte.

    StringRef Data;

    /// Offset from Data to the start of the file.

    uint16_t StartOfFile;

    Expected<bool> isThinMember() const;

  public:

    Child(const Archive *Parent, const char *Start, Error *Err);

    Child(const Archive *Parent, StringRef Data, uint16_t StartOfFile);

    Child(const Child &C)

        : Parent(C.Parent), Data(C.Data), StartOfFile(C.StartOfFile) {

      if (C.Header)

        Header = C.Header->clone();

    }

    Child(Child &&C) {

      Parent = std::move(C.Parent);

      Header = std::move(C.Header);

      Data = C.Data;

      StartOfFile = C.StartOfFile;

    }

    Child &operator=(Child &&C) noexcept {

      if (&C == this)

        return *this;

      Parent = std::move(C.Parent);

      Header = std::move(C.Header);

      Data = C.Data;

      StartOfFile = C.StartOfFile;

      return *this;

    }

    Child &operator=(const Child &C) {

      if (&C == this)

        return *this;

      Parent = C.Parent;

      if (C.Header)

        Header = C.Header->clone();

      Data = C.Data;

      StartOfFile = C.StartOfFile;

      return *this;

    }

    bool operator==(const Child &other) const {

      assert(!Parent || !other.Parent || Parent == other.Parent);

      return Data.begin() == other.Data.begin();

    }

    const Archive *getParent() const { return Parent; }

    Expected<Child> getNext() const;

    Expected<StringRef> getName() const;

    Expected<std::string> getFullName() const;

    Expected<StringRef> getRawName() const { return Header->getRawName(); }

    Expected<sys::TimePoint<std::chrono::seconds>> getLastModified() const {

      return Header->getLastModified();

    }

    StringRef getRawLastModified() const {

      return Header->getRawLastModified();

    }

    Expected<unsigned> getUID() const { return Header->getUID(); }

    Expected<unsigned> getGID() const { return Header->getGID(); }

    Expected<sys::fs::perms> getAccessMode() const {

      return Header->getAccessMode();

    }

    /// \return the size of the archive member without the header or padding.

    Expected<uint64_t> getSize() const;

    /// \return the size in the archive header for this member.

    Expected<uint64_t> getRawSize() const;

    Expected<StringRef> getBuffer() const;

    uint64_t getChildOffset() const;

    uint64_t getDataOffset() const { return getChildOffset() + StartOfFile; }

    Expected<MemoryBufferRef> getMemoryBufferRef() const;

    Expected<std::unique_ptr<Binary>>

    getAsBinary(LLVMContext *Context = nullptr) const;

  };

  class ChildFallibleIterator {

    Child C;

  public:

    ChildFallibleIterator() : C(Child(nullptr, nullptr, nullptr)) {}

    ChildFallibleIterator(const Child &C) : C(C) {}

    const Child *operator->() const { return &C; }

    const Child &operator*() const { return C; }

    bool operator==(const ChildFallibleIterator &other) const {

      // Ignore errors here: If an error occurred during increment then getNext

      // will have been set to child_end(), and the following comparison should

      // do the right thing.

      return C == other.C;

    }

    bool operator!=(const ChildFallibleIterator &other) const {

      return !(*this == other);

    }

    Error inc() {

      auto NextChild = C.getNext();

      if (!NextChild)

        return NextChild.takeError();

      C = std::move(*NextChild);

      return Error::success();

    }

  };

  using child_iterator = fallible_iterator<ChildFallibleIterator>;

  class Symbol {

    const Archive *Parent;

    uint32_t SymbolIndex;

    uint32_t StringIndex; // Extra index to the string.

  public:

    Symbol(const Archive *p, uint32_t symi, uint32_t stri)

        : Parent(p), SymbolIndex(symi), StringIndex(stri) {}

    bool operator==(const Symbol &other) const {

      return (Parent == other.Parent) && (SymbolIndex == other.SymbolIndex);

    }

    StringRef getName() const;

    Expected<Child> getMember() const;

    Symbol getNext() const;

  };

  class symbol_iterator {

    Symbol symbol;

  public:

    symbol_iterator(const Symbol &s) : symbol(s) {}

    const Symbol *operator->() const { return &symbol; }

    const Symbol &operator*() const { return symbol; }

    bool operator==(const symbol_iterator &other) const {

      return symbol == other.symbol;

    }

    bool operator!=(const symbol_iterator &other) const {

      return !(*this == other);

    }

    symbol_iterator &operator++() { // Preincrement

      symbol = symbol.getNext();

      return *this;

    }

  };

  Archive(MemoryBufferRef Source, Error &Err);

  static Expected<std::unique_ptr<Archive>> create(MemoryBufferRef Source);

  /// Size field is 10 decimal digits long

  static const uint64_t MaxMemberSize = 9999999999;

  enum Kind { K_GNU, K_GNU64, K_BSD, K_DARWIN, K_DARWIN64, K_COFF, K_AIXBIG };

  Kind kind() const { return (Kind)Format; }

  bool isThin() const { return IsThin; }

  static object::Archive::Kind getDefaultKindForHost();

  child_iterator child_begin(Error &Err, bool SkipInternal = true) const;

  child_iterator child_end() const;

  iterator_range<child_iterator> children(Error &Err,

                                          bool SkipInternal = true) const {

    return make_range(child_begin(Err, SkipInternal), child_end());

  }

  symbol_iterator symbol_begin() const;

  symbol_iterator symbol_end() const;

  iterator_range<symbol_iterator> symbols() const {

    return make_range(symbol_begin(), symbol_end());

  }

  static bool classof(Binary const *v) { return v->isArchive(); }

  // check if a symbol is in the archive

  Expected<std::optional<Child>> findSym(StringRef name) const;

  virtual bool isEmpty() const;

  bool hasSymbolTable() const;

  StringRef getSymbolTable() const { return SymbolTable; }

  StringRef getStringTable() const { return StringTable; }

  uint32_t getNumberOfSymbols() const;

  virtual uint64_t getFirstChildOffset() const { return getArchiveMagicLen(); }

  std::vector<std::unique_ptr<MemoryBuffer>> takeThinBuffers() {

    return std::move(ThinBuffers);

  }

  std::unique_ptr<AbstractArchiveMemberHeader>

  createArchiveMemberHeader(const char *RawHeaderPtr, uint64_t Size,

                            Error *Err) const;

protected:

  uint64_t getArchiveMagicLen() const;

  void setFirstRegular(const Child &C);

  StringRef SymbolTable;

  StringRef StringTable;

private:

  StringRef FirstRegularData;

  uint16_t FirstRegularStartOfFile = -1;

  unsigned Format : 3;

  unsigned IsThin : 1;

  mutable std::vector<std::unique_ptr<MemoryBuffer>> ThinBuffers;

};

class BigArchive : public Archive {

public:

  /// Fixed-Length Header.

  struct FixLenHdr {

    char Magic[sizeof(BigArchiveMagic) - 1]; ///< Big archive magic string.

    char MemOffset[20];                      ///< Offset to member table.

    char GlobSymOffset[20];                  ///< Offset to global symbol table.

    char

        GlobSym64Offset[20]; ///< Offset global symbol table for 64-bit objects.

    char FirstChildOffset[20]; ///< Offset to first archive member.

    char LastChildOffset[20];  ///< Offset to last archive member.

    char FreeOffset[20];       ///< Offset to first mem on free list.

  };

  const FixLenHdr *ArFixLenHdr;

  uint64_t FirstChildOffset = 0;

  uint64_t LastChildOffset = 0;

public:

  BigArchive(MemoryBufferRef Source, Error &Err);

  uint64_t getFirstChildOffset() const override { return FirstChildOffset; }

  uint64_t getLastChildOffset() const { return LastChildOffset; }

  bool isEmpty() const override {

    return Data.getBufferSize() == sizeof(FixLenHdr);

  };

};

} // end namespace object

} // end namespace llvm

#endif // LLVM_OBJECT_ARCHIVE_H