tools/llvm-objcopy/CopyConfig.h

   1 //===- CopyConfig.h -------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_TOOLS_LLVM_OBJCOPY_COPY_CONFIG_H
  10 #define LLVM_TOOLS_LLVM_OBJCOPY_COPY_CONFIG_H
  11
  12 #include "llvm/ADT/ArrayRef.h"
  13 #include "llvm/ADT/BitmaskEnum.h"
  14 #include "llvm/ADT/Optional.h"
  15 #include "llvm/ADT/SmallVector.h"
  16 #include "llvm/ADT/StringMap.h"
  17 #include "llvm/ADT/StringRef.h"
  18 #include "llvm/Object/ELFTypes.h"
  19 #include "llvm/Support/Allocator.h"
  20 #include "llvm/Support/Error.h"
  21 #include "llvm/Support/Regex.h"
  22 // Necessary for llvm::DebugCompressionType::None
  23 #include "llvm/Target/TargetOptions.h"
  24 #include <vector>
  25
  26 namespace llvm {
  27 namespace objcopy {
  28
  29 enum class FileFormat {
  30   Unspecified,
  31   ELF,
  32   Binary,
  33   IHex,
  34 };
  35
  36 // This type keeps track of the machine info for various architectures. This
  37 // lets us map architecture names to ELF types and the e_machine value of the
  38 // ELF file.
  39 struct MachineInfo {
  40   MachineInfo(uint16_t EM, uint8_t ABI, bool Is64, bool IsLittle)
  41       : EMachine(EM), OSABI(ABI), Is64Bit(Is64), IsLittleEndian(IsLittle) {}
  42   // Alternative constructor that defaults to NONE for OSABI.
  43   MachineInfo(uint16_t EM, bool Is64, bool IsLittle)
  44       : MachineInfo(EM, ELF::ELFOSABI_NONE, Is64, IsLittle) {}
  45   // Default constructor for unset fields.
  46   MachineInfo() : MachineInfo(0, 0, false, false) {}
  47   uint16_t EMachine;
  48   uint8_t OSABI;
  49   bool Is64Bit;
  50   bool IsLittleEndian;
  51 };
  52
  53 // Flags set by --set-section-flags or --rename-section. Interpretation of these
  54 // is format-specific and not all flags are meaningful for all object file
  55 // formats. This is a bitmask; many section flags may be set.
  56 enum SectionFlag {
  57   SecNone = 0,
  58   SecAlloc = 1 << 0,
  59   SecLoad = 1 << 1,
  60   SecNoload = 1 << 2,
  61   SecReadonly = 1 << 3,
  62   SecDebug = 1 << 4,
  63   SecCode = 1 << 5,
  64   SecData = 1 << 6,
  65   SecRom = 1 << 7,
  66   SecMerge = 1 << 8,
  67   SecStrings = 1 << 9,
  68   SecContents = 1 << 10,
  69   SecShare = 1 << 11,
  70   LLVM_MARK_AS_BITMASK_ENUM(/* LargestValue = */ SecShare)
  71 };
  72
  73 struct SectionRename {
  74   StringRef OriginalName;
  75   StringRef NewName;
  76   Optional<SectionFlag> NewFlags;
  77 };
  78
  79 struct SectionFlagsUpdate {
  80   StringRef Name;
  81   SectionFlag NewFlags;
  82 };
  83
  84 enum class DiscardType {
  85   None,   // Default
  86   All,    // --discard-all (-x)
  87   Locals, // --discard-locals (-X)
  88 };
  89
  90 class NameOrRegex {
  91   StringRef Name;
  92   // Regex is shared between multiple CopyConfig instances.
  93   std::shared_ptr<Regex> R;
  94
  95 public:
  96   NameOrRegex(StringRef Pattern, bool IsRegex);
  97   bool operator==(StringRef S) const { return R ? R->match(S) : Name == S; }
  98   bool operator!=(StringRef S) const { return !operator==(S); }
  99 };
 100
 101 // Matcher that checks symbol or section names against the command line flags
 102 // provided for that option.
 103 class NameMatcher {
 104   std::vector<NameOrRegex> Matchers;
 105
 106 public:
 107   void addMatcher(NameOrRegex Matcher) {
 108     Matchers.push_back(std::move(Matcher));
 109   }
 110   bool matches(StringRef S) const { return is_contained(Matchers, S); }
 111   bool empty() const { return Matchers.empty(); }
 112 };
 113
 114 struct NewSymbolInfo {
 115   StringRef SymbolName;
 116   StringRef SectionName;
 117   uint64_t Value = 0;
 118   uint8_t Type = ELF::STT_NOTYPE;
 119   uint8_t Bind = ELF::STB_GLOBAL;
 120   uint8_t Visibility = ELF::STV_DEFAULT;
 121 };
 122
 123 // Configuration for copying/stripping a single file.
 124 struct CopyConfig {
 125   // Main input/output options
 126   StringRef InputFilename;
 127   FileFormat InputFormat;
 128   StringRef OutputFilename;
 129   FileFormat OutputFormat;
 130
 131   // Only applicable for --input-format=binary
 132   MachineInfo BinaryArch;
 133   // Only applicable when --output-format!=binary (e.g. elf64-x86-64).
 134   Optional<MachineInfo> OutputArch;
 135
 136   // Advanced options
 137   StringRef AddGnuDebugLink;
 138   // Cached gnu_debuglink's target CRC
 139   uint32_t GnuDebugLinkCRC32;
 140   StringRef BuildIdLinkDir;
 141   Optional<StringRef> BuildIdLinkInput;
 142   Optional<StringRef> BuildIdLinkOutput;
 143   Optional<StringRef> ExtractPartition;
 144   StringRef SplitDWO;
 145   StringRef SymbolsPrefix;
 146   StringRef AllocSectionsPrefix;
 147   DiscardType DiscardMode = DiscardType::None;
 148   Optional<uint8_t> NewSymbolVisibility;
 149
 150   // Repeated options
 151   std::vector<StringRef> AddSection;
 152   std::vector<StringRef> DumpSection;
 153   std::vector<NewSymbolInfo> SymbolsToAdd;
 154
 155   // Section matchers
 156   NameMatcher KeepSection;
 157   NameMatcher OnlySection;
 158   NameMatcher ToRemove;
 159
 160   // Symbol matchers
 161   NameMatcher SymbolsToGlobalize;
 162   NameMatcher SymbolsToKeep;
 163   NameMatcher SymbolsToLocalize;
 164   NameMatcher SymbolsToRemove;
 165   NameMatcher UnneededSymbolsToRemove;
 166   NameMatcher SymbolsToWeaken;
 167   NameMatcher SymbolsToKeepGlobal;
 168
 169   // Map options
 170   StringMap<SectionRename> SectionsToRename;
 171   StringMap<SectionFlagsUpdate> SetSectionFlags;
 172   StringMap<StringRef> SymbolsToRename;
 173
 174   // ELF entry point address expression. The input parameter is an entry point
 175   // address in the input ELF file. The entry address in the output file is
 176   // calculated with EntryExpr(input_address), when either --set-start or
 177   // --change-start is used.
 178   std::function<uint64_t(uint64_t)> EntryExpr;
 179
 180   // Boolean options
 181   bool AllowBrokenLinks = false;
 182   bool DeterministicArchives = true;
 183   bool ExtractDWO = false;
 184   bool ExtractMainPartition = false;
 185   bool KeepFileSymbols = false;
 186   bool LocalizeHidden = false;
 187   bool OnlyKeepDebug = false;
 188   bool PreserveDates = false;
 189   bool StripAll = false;
 190   bool StripAllGNU = false;
 191   bool StripDWO = false;
 192   bool StripDebug = false;
 193   bool StripNonAlloc = false;
 194   bool StripSections = false;
 195   bool StripUnneeded = false;
 196   bool Weaken = false;
 197   bool DecompressDebugSections = false;
 198   DebugCompressionType CompressionType = DebugCompressionType::None;
 199 };
 200
 201 // Configuration for the overall invocation of this tool. When invoked as
 202 // objcopy, will always contain exactly one CopyConfig. When invoked as strip,
 203 // will contain one or more CopyConfigs.
 204 struct DriverConfig {
 205   SmallVector<CopyConfig, 1> CopyConfigs;
 206   BumpPtrAllocator Alloc;
 207 };
 208
 209 // ParseObjcopyOptions returns the config and sets the input arguments. If a
 210 // help flag is set then ParseObjcopyOptions will print the help messege and
 211 // exit.
 212 Expected<DriverConfig> parseObjcopyOptions(ArrayRef<const char *> ArgsArr);
 213
 214 // ParseStripOptions returns the config and sets the input arguments. If a
 215 // help flag is set then ParseStripOptions will print the help messege and
 216 // exit. ErrorCallback is used to handle recoverable errors. An Error returned
 217 // by the callback aborts the parsing and is then returned by this function.
 218 Expected<DriverConfig>
 219 parseStripOptions(ArrayRef<const char *> ArgsArr,
 220                   std::function<Error(Error)> ErrorCallback);
 221
 222 } // namespace objcopy
 223 } // namespace llvm
 224
 225 #endif