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 "ELF/ELFConfig.h"
  13 #include "llvm/ADT/ArrayRef.h"
  14 #include "llvm/ADT/BitmaskEnum.h"
  15 #include "llvm/ADT/Optional.h"
  16 #include "llvm/ADT/SmallVector.h"
  17 #include "llvm/ADT/StringMap.h"
  18 #include "llvm/ADT/StringRef.h"
  19 #include "llvm/Object/ELFTypes.h"
  20 #include "llvm/Support/Allocator.h"
  21 #include "llvm/Support/Error.h"
  22 #include "llvm/Support/GlobPattern.h"
  23 #include "llvm/Support/Regex.h"
  24 // Necessary for llvm::DebugCompressionType::None
  25 #include "llvm/Target/TargetOptions.h"
  26 #include <vector>
  27
  28 namespace llvm {
  29 namespace objcopy {
  30
  31 enum class FileFormat {
  32   Unspecified,
  33   ELF,
  34   Binary,
  35   IHex,
  36 };
  37
  38 // This type keeps track of the machine info for various architectures. This
  39 // lets us map architecture names to ELF types and the e_machine value of the
  40 // ELF file.
  41 struct MachineInfo {
  42   MachineInfo(uint16_t EM, uint8_t ABI, bool Is64, bool IsLittle)
  43       : EMachine(EM), OSABI(ABI), Is64Bit(Is64), IsLittleEndian(IsLittle) {}
  44   // Alternative constructor that defaults to NONE for OSABI.
  45   MachineInfo(uint16_t EM, bool Is64, bool IsLittle)
  46       : MachineInfo(EM, ELF::ELFOSABI_NONE, Is64, IsLittle) {}
  47   // Default constructor for unset fields.
  48   MachineInfo() : MachineInfo(0, 0, false, false) {}
  49   uint16_t EMachine;
  50   uint8_t OSABI;
  51   bool Is64Bit;
  52   bool IsLittleEndian;
  53 };
  54
  55 // Flags set by --set-section-flags or --rename-section. Interpretation of these
  56 // is format-specific and not all flags are meaningful for all object file
  57 // formats. This is a bitmask; many section flags may be set.
  58 enum SectionFlag {
  59   SecNone = 0,
  60   SecAlloc = 1 << 0,
  61   SecLoad = 1 << 1,
  62   SecNoload = 1 << 2,
  63   SecReadonly = 1 << 3,
  64   SecDebug = 1 << 4,
  65   SecCode = 1 << 5,
  66   SecData = 1 << 6,
  67   SecRom = 1 << 7,
  68   SecMerge = 1 << 8,
  69   SecStrings = 1 << 9,
  70   SecContents = 1 << 10,
  71   SecShare = 1 << 11,
  72   LLVM_MARK_AS_BITMASK_ENUM(/* LargestValue = */ SecShare)
  73 };
  74
  75 struct SectionRename {
  76   StringRef OriginalName;
  77   StringRef NewName;
  78   Optional<SectionFlag> NewFlags;
  79 };
  80
  81 struct SectionFlagsUpdate {
  82   StringRef Name;
  83   SectionFlag NewFlags;
  84 };
  85
  86 enum class DiscardType {
  87   None,   // Default
  88   All,    // --discard-all (-x)
  89   Locals, // --discard-locals (-X)
  90 };
  91
  92 enum class MatchStyle {
  93   Literal,  // Default for symbols.
  94   Wildcard, // Default for sections, or enabled with --wildcard (-w).
  95   Regex,    // Enabled with --regex.
  96 };
  97
  98 class NameOrPattern {
  99   StringRef Name;
 100   // Regex is shared between multiple CopyConfig instances.
 101   std::shared_ptr<Regex> R;
 102   std::shared_ptr<GlobPattern> G;
 103   bool IsPositiveMatch = true;
 104
 105   NameOrPattern(StringRef N) : Name(N) {}
 106   NameOrPattern(std::shared_ptr<Regex> R) : R(R) {}
 107   NameOrPattern(std::shared_ptr<GlobPattern> G, bool IsPositiveMatch)
 108       : G(G), IsPositiveMatch(IsPositiveMatch) {}
 109
 110 public:
 111   // ErrorCallback is used to handle recoverable errors. An Error returned
 112   // by the callback aborts the parsing and is then returned by this function.
 113   static Expected<NameOrPattern>
 114   create(StringRef Pattern, MatchStyle MS,
 115          llvm::function_ref<Error(Error)> ErrorCallback);
 116
 117   bool isPositiveMatch() const { return IsPositiveMatch; }
 118   bool operator==(StringRef S) const {
 119     return R ? R->match(S) : G ? G->match(S) : Name == S;
 120   }
 121   bool operator!=(StringRef S) const { return !operator==(S); }
 122 };
 123
 124 // Matcher that checks symbol or section names against the command line flags
 125 // provided for that option.
 126 class NameMatcher {
 127   std::vector<NameOrPattern> PosMatchers;
 128   std::vector<NameOrPattern> NegMatchers;
 129
 130 public:
 131   Error addMatcher(Expected<NameOrPattern> Matcher) {
 132     if (!Matcher)
 133       return Matcher.takeError();
 134     if (Matcher->isPositiveMatch())
 135       PosMatchers.push_back(std::move(*Matcher));
 136     else
 137       NegMatchers.push_back(std::move(*Matcher));
 138     return Error::success();
 139   }
 140   bool matches(StringRef S) const {
 141     return is_contained(PosMatchers, S) && !is_contained(NegMatchers, S);
 142   }
 143   bool empty() const { return PosMatchers.empty() && NegMatchers.empty(); }
 144 };
 145
 146 // Configuration for copying/stripping a single file.
 147 struct CopyConfig {
 148   // Format-specific options to be initialized lazily when needed.
 149   Optional<elf::ELFCopyConfig> ELF;
 150
 151   // Main input/output options
 152   StringRef InputFilename;
 153   FileFormat InputFormat;
 154   StringRef OutputFilename;
 155   FileFormat OutputFormat;
 156
 157   // Only applicable when --output-format!=binary (e.g. elf64-x86-64).
 158   Optional<MachineInfo> OutputArch;
 159
 160   // Advanced options
 161   StringRef AddGnuDebugLink;
 162   // Cached gnu_debuglink's target CRC
 163   uint32_t GnuDebugLinkCRC32;
 164   StringRef BuildIdLinkDir;
 165   Optional<StringRef> BuildIdLinkInput;
 166   Optional<StringRef> BuildIdLinkOutput;
 167   Optional<StringRef> ExtractPartition;
 168   StringRef SplitDWO;
 169   StringRef SymbolsPrefix;
 170   StringRef AllocSectionsPrefix;
 171   DiscardType DiscardMode = DiscardType::None;
 172   Optional<StringRef> NewSymbolVisibility;
 173
 174   // Repeated options
 175   std::vector<StringRef> AddSection;
 176   std::vector<StringRef> DumpSection;
 177   std::vector<StringRef> SymbolsToAdd;
 178
 179   // Section matchers
 180   NameMatcher KeepSection;
 181   NameMatcher OnlySection;
 182   NameMatcher ToRemove;
 183
 184   // Symbol matchers
 185   NameMatcher SymbolsToGlobalize;
 186   NameMatcher SymbolsToKeep;
 187   NameMatcher SymbolsToLocalize;
 188   NameMatcher SymbolsToRemove;
 189   NameMatcher UnneededSymbolsToRemove;
 190   NameMatcher SymbolsToWeaken;
 191   NameMatcher SymbolsToKeepGlobal;
 192
 193   // Map options
 194   StringMap<SectionRename> SectionsToRename;
 195   StringMap<uint64_t> SetSectionAlignment;
 196   StringMap<SectionFlagsUpdate> SetSectionFlags;
 197   StringMap<StringRef> SymbolsToRename;
 198
 199   // ELF entry point address expression. The input parameter is an entry point
 200   // address in the input ELF file. The entry address in the output file is
 201   // calculated with EntryExpr(input_address), when either --set-start or
 202   // --change-start is used.
 203   std::function<uint64_t(uint64_t)> EntryExpr;
 204
 205   // Boolean options
 206   bool AllowBrokenLinks = false;
 207   bool DeterministicArchives = true;
 208   bool ExtractDWO = false;
 209   bool ExtractMainPartition = false;
 210   bool KeepFileSymbols = false;
 211   bool LocalizeHidden = false;
 212   bool OnlyKeepDebug = false;
 213   bool PreserveDates = false;
 214   bool StripAll = false;
 215   bool StripAllGNU = false;
 216   bool StripDWO = false;
 217   bool StripDebug = false;
 218   bool StripNonAlloc = false;
 219   bool StripSections = false;
 220   bool StripUnneeded = false;
 221   bool Weaken = false;
 222   bool DecompressDebugSections = false;
 223   DebugCompressionType CompressionType = DebugCompressionType::None;
 224
 225   // parseELFConfig performs ELF-specific command-line parsing. Fills `ELF` on
 226   // success or returns an Error otherwise.
 227   Error parseELFConfig() {
 228     if (!ELF) {
 229       Expected<elf::ELFCopyConfig> ELFConfig = elf::parseConfig(*this);
 230       if (!ELFConfig)
 231         return ELFConfig.takeError();
 232       ELF = *ELFConfig;
 233     }
 234     return Error::success();
 235   }
 236 };
 237
 238 // Configuration for the overall invocation of this tool. When invoked as
 239 // objcopy, will always contain exactly one CopyConfig. When invoked as strip,
 240 // will contain one or more CopyConfigs.
 241 struct DriverConfig {
 242   SmallVector<CopyConfig, 1> CopyConfigs;
 243   BumpPtrAllocator Alloc;
 244 };
 245
 246 // ParseObjcopyOptions returns the config and sets the input arguments. If a
 247 // help flag is set then ParseObjcopyOptions will print the help messege and
 248 // exit. ErrorCallback is used to handle recoverable errors. An Error returned
 249 // by the callback aborts the parsing and is then returned by this function.
 250 Expected<DriverConfig>
 251 parseObjcopyOptions(ArrayRef<const char *> ArgsArr,
 252                     llvm::function_ref<Error(Error)> ErrorCallback);
 253
 254 // ParseStripOptions returns the config and sets the input arguments. If a
 255 // help flag is set then ParseStripOptions will print the help messege and
 256 // exit. ErrorCallback is used to handle recoverable errors. An Error returned
 257 // by the callback aborts the parsing and is then returned by this function.
 258 Expected<DriverConfig>
 259 parseStripOptions(ArrayRef<const char *> ArgsArr,
 260                   llvm::function_ref<Error(Error)> ErrorCallback);
 261
 262 } // namespace objcopy
 263 } // namespace llvm
 264
 265 #endif