xref: /llvm-project/llvm/tools/llvm-objcopy/llvm-objcopy.cpp (revision f2af0607000cb18bf9292457ea247bb6602b4cdb) 
1 //===- llvm-objcopy.cpp ---------------------------------------------------===//
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 #include "llvm-objcopy.h"
10 #include "Buffer.h"
11 #include "COFF/COFFObjcopy.h"
12 #include "CopyConfig.h"
13 #include "ELF/ELFObjcopy.h"
14 #include "MachO/MachOObjcopy.h"
15 #include "wasm/WasmObjcopy.h"
16 
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/ADT/Twine.h"
21 #include "llvm/Object/Archive.h"
22 #include "llvm/Object/ArchiveWriter.h"
23 #include "llvm/Object/Binary.h"
24 #include "llvm/Object/COFF.h"
25 #include "llvm/Object/ELFObjectFile.h"
26 #include "llvm/Object/ELFTypes.h"
27 #include "llvm/Object/Error.h"
28 #include "llvm/Object/MachO.h"
29 #include "llvm/Object/Wasm.h"
30 #include "llvm/Option/Arg.h"
31 #include "llvm/Option/ArgList.h"
32 #include "llvm/Option/Option.h"
33 #include "llvm/Support/Casting.h"
34 #include "llvm/Support/CommandLine.h"
35 #include "llvm/Support/Error.h"
36 #include "llvm/Support/ErrorHandling.h"
37 #include "llvm/Support/ErrorOr.h"
38 #include "llvm/Support/InitLLVM.h"
39 #include "llvm/Support/Memory.h"
40 #include "llvm/Support/Path.h"
41 #include "llvm/Support/Process.h"
42 #include "llvm/Support/StringSaver.h"
43 #include "llvm/Support/WithColor.h"
44 #include "llvm/Support/raw_ostream.h"
45 #include <algorithm>
46 #include <cassert>
47 #include <cstdlib>
48 #include <memory>
49 #include <string>
50 #include <system_error>
51 #include <utility>
52 
53 namespace llvm {
54 namespace objcopy {
55 
56 // The name this program was invoked as.
57 StringRef ToolName;
58 
59 LLVM_ATTRIBUTE_NORETURN void error(Twine Message) {
60   WithColor::error(errs(), ToolName) << Message << "\n";
61   exit(1);
62 }
63 
64 LLVM_ATTRIBUTE_NORETURN void error(Error E) {
65   assert(E);
66   std::string Buf;
67   raw_string_ostream OS(Buf);
68   logAllUnhandledErrors(std::move(E), OS);
69   OS.flush();
70   WithColor::error(errs(), ToolName) << Buf;
71   exit(1);
72 }
73 
74 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, std::error_code EC) {
75   assert(EC);
76   error(createFileError(File, EC));
77 }
78 
79 LLVM_ATTRIBUTE_NORETURN void reportError(StringRef File, Error E) {
80   assert(E);
81   std::string Buf;
82   raw_string_ostream OS(Buf);
83   logAllUnhandledErrors(std::move(E), OS);
84   OS.flush();
85   WithColor::error(errs(), ToolName) << "'" << File << "': " << Buf;
86   exit(1);
87 }
88 
89 ErrorSuccess reportWarning(Error E) {
90   assert(E);
91   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
92   return Error::success();
93 }
94 
95 } // end namespace objcopy
96 } // end namespace llvm
97 
98 using namespace llvm;
99 using namespace llvm::object;
100 using namespace llvm::objcopy;
101 
102 // For regular archives this function simply calls llvm::writeArchive,
103 // For thin archives it writes the archive file itself as well as its members.
104 static Error deepWriteArchive(StringRef ArcName,
105                               ArrayRef<NewArchiveMember> NewMembers,
106                               bool WriteSymtab, object::Archive::Kind Kind,
107                               bool Deterministic, bool Thin) {
108   if (Error E = writeArchive(ArcName, NewMembers, WriteSymtab, Kind,
109                              Deterministic, Thin))
110     return createFileError(ArcName, std::move(E));
111 
112   if (!Thin)
113     return Error::success();
114 
115   for (const NewArchiveMember &Member : NewMembers) {
116     // Internally, FileBuffer will use the buffer created by
117     // FileOutputBuffer::create, for regular files (that is the case for
118     // deepWriteArchive) FileOutputBuffer::create will return OnDiskBuffer.
119     // OnDiskBuffer uses a temporary file and then renames it. So in reality
120     // there is no inefficiency / duplicated in-memory buffers in this case. For
121     // now in-memory buffers can not be completely avoided since
122     // NewArchiveMember still requires them even though writeArchive does not
123     // write them on disk.
124     FileBuffer FB(Member.MemberName);
125     if (Error E = FB.allocate(Member.Buf->getBufferSize()))
126       return E;
127     std::copy(Member.Buf->getBufferStart(), Member.Buf->getBufferEnd(),
128               FB.getBufferStart());
129     if (Error E = FB.commit())
130       return E;
131   }
132   return Error::success();
133 }
134 
135 /// The function executeObjcopyOnIHex does the dispatch based on the format
136 /// of the output specified by the command line options.
137 static Error executeObjcopyOnIHex(CopyConfig &Config, MemoryBuffer &In,
138                                   Buffer &Out) {
139   // TODO: support output formats other than ELF.
140   if (Error E = Config.parseELFConfig())
141     return E;
142   return elf::executeObjcopyOnIHex(Config, In, Out);
143 }
144 
145 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
146 /// of the output specified by the command line options.
147 static Error executeObjcopyOnRawBinary(CopyConfig &Config, MemoryBuffer &In,
148                                        Buffer &Out) {
149   switch (Config.OutputFormat) {
150   case FileFormat::ELF:
151   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
152   // output format is binary/ihex or it's not given. This behavior differs from
153   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
154   case FileFormat::Binary:
155   case FileFormat::IHex:
156   case FileFormat::Unspecified:
157     if (Error E = Config.parseELFConfig())
158       return E;
159     return elf::executeObjcopyOnRawBinary(Config, In, Out);
160   }
161 
162   llvm_unreachable("unsupported output format");
163 }
164 
165 /// The function executeObjcopyOnBinary does the dispatch based on the format
166 /// of the input binary (ELF, MachO or COFF).
167 static Error executeObjcopyOnBinary(CopyConfig &Config, object::Binary &In,
168                                     Buffer &Out) {
169   if (auto *ELFBinary = dyn_cast<object::ELFObjectFileBase>(&In)) {
170     if (Error E = Config.parseELFConfig())
171       return E;
172     return elf::executeObjcopyOnBinary(Config, *ELFBinary, Out);
173   } else if (auto *COFFBinary = dyn_cast<object::COFFObjectFile>(&In))
174     return coff::executeObjcopyOnBinary(Config, *COFFBinary, Out);
175   else if (auto *MachOBinary = dyn_cast<object::MachOObjectFile>(&In))
176     return macho::executeObjcopyOnBinary(Config, *MachOBinary, Out);
177   else if (auto *WasmBinary = dyn_cast<object::WasmObjectFile>(&In))
178     return objcopy::wasm::executeObjcopyOnBinary(Config, *WasmBinary, Out);
179   else
180     return createStringError(object_error::invalid_file_type,
181                              "unsupported object file format");
182 }
183 
184 static Error executeObjcopyOnArchive(CopyConfig &Config, const Archive &Ar) {
185   std::vector<NewArchiveMember> NewArchiveMembers;
186   Error Err = Error::success();
187   for (const Archive::Child &Child : Ar.children(Err)) {
188     Expected<StringRef> ChildNameOrErr = Child.getName();
189     if (!ChildNameOrErr)
190       return createFileError(Ar.getFileName(), ChildNameOrErr.takeError());
191 
192     Expected<std::unique_ptr<Binary>> ChildOrErr = Child.getAsBinary();
193     if (!ChildOrErr)
194       return createFileError(Ar.getFileName() + "(" + *ChildNameOrErr + ")",
195                              ChildOrErr.takeError());
196 
197     MemBuffer MB(ChildNameOrErr.get());
198     if (Error E = executeObjcopyOnBinary(Config, *ChildOrErr->get(), MB))
199       return E;
200 
201     Expected<NewArchiveMember> Member =
202         NewArchiveMember::getOldMember(Child, Config.DeterministicArchives);
203     if (!Member)
204       return createFileError(Ar.getFileName(), Member.takeError());
205     Member->Buf = MB.releaseMemoryBuffer();
206     Member->MemberName = Member->Buf->getBufferIdentifier();
207     NewArchiveMembers.push_back(std::move(*Member));
208   }
209   if (Err)
210     return createFileError(Config.InputFilename, std::move(Err));
211 
212   return deepWriteArchive(Config.OutputFilename, NewArchiveMembers,
213                           Ar.hasSymbolTable(), Ar.kind(),
214                           Config.DeterministicArchives, Ar.isThin());
215 }
216 
217 static Error restoreStatOnFile(StringRef Filename,
218                                const sys::fs::file_status &Stat,
219                                bool PreserveDates) {
220   int FD;
221 
222   // Writing to stdout should not be treated as an error here, just
223   // do not set access/modification times or permissions.
224   if (Filename == "-")
225     return Error::success();
226 
227   if (auto EC =
228           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
229     return createFileError(Filename, EC);
230 
231   if (PreserveDates)
232     if (auto EC = sys::fs::setLastAccessAndModificationTime(
233             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
234       return createFileError(Filename, EC);
235 
236   sys::fs::file_status OStat;
237   if (std::error_code EC = sys::fs::status(FD, OStat))
238     return createFileError(Filename, EC);
239   if (OStat.type() == sys::fs::file_type::regular_file)
240 #ifdef _WIN32
241     if (auto EC = sys::fs::setPermissions(
242             Filename, static_cast<sys::fs::perms>(Stat.permissions() &
243                                                   ~sys::fs::getUmask())))
244 #else
245     if (auto EC = sys::fs::setPermissions(
246             FD, static_cast<sys::fs::perms>(Stat.permissions() &
247                                             ~sys::fs::getUmask())))
248 #endif
249       return createFileError(Filename, EC);
250 
251   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
252     return createFileError(Filename, EC);
253 
254   return Error::success();
255 }
256 
257 /// The function executeObjcopy does the higher level dispatch based on the type
258 /// of input (raw binary, archive or single object file) and takes care of the
259 /// format-agnostic modifications, i.e. preserving dates.
260 static Error executeObjcopy(CopyConfig &Config) {
261   sys::fs::file_status Stat;
262   if (Config.InputFilename != "-") {
263     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
264       return createFileError(Config.InputFilename, EC);
265   } else {
266     Stat.permissions(static_cast<sys::fs::perms>(0777));
267   }
268 
269   using ProcessRawFn = Error (*)(CopyConfig &, MemoryBuffer &, Buffer &);
270   ProcessRawFn ProcessRaw;
271   switch (Config.InputFormat) {
272   case FileFormat::Binary:
273     ProcessRaw = executeObjcopyOnRawBinary;
274     break;
275   case FileFormat::IHex:
276     ProcessRaw = executeObjcopyOnIHex;
277     break;
278   default:
279     ProcessRaw = nullptr;
280   }
281 
282   if (ProcessRaw) {
283     auto BufOrErr = MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
284     if (!BufOrErr)
285       return createFileError(Config.InputFilename, BufOrErr.getError());
286     FileBuffer FB(Config.OutputFilename);
287     if (Error E = ProcessRaw(Config, *BufOrErr->get(), FB))
288       return E;
289   } else {
290     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
291         createBinary(Config.InputFilename);
292     if (!BinaryOrErr)
293       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
294 
295     if (Archive *Ar = dyn_cast<Archive>(BinaryOrErr.get().getBinary())) {
296       if (Error E = executeObjcopyOnArchive(Config, *Ar))
297         return E;
298     } else {
299       FileBuffer FB(Config.OutputFilename);
300       if (Error E = executeObjcopyOnBinary(Config,
301                                            *BinaryOrErr.get().getBinary(), FB))
302         return E;
303     }
304   }
305 
306   if (Error E =
307           restoreStatOnFile(Config.OutputFilename, Stat, Config.PreserveDates))
308     return E;
309 
310   if (!Config.SplitDWO.empty()) {
311     Stat.permissions(static_cast<sys::fs::perms>(0666));
312     if (Error E =
313             restoreStatOnFile(Config.SplitDWO, Stat, Config.PreserveDates))
314       return E;
315   }
316 
317   return Error::success();
318 }
319 
320 namespace {
321 
322 enum class ToolType { Objcopy, Strip, InstallNameTool };
323 
324 } // anonymous namespace
325 
326 int main(int argc, char **argv) {
327   InitLLVM X(argc, argv);
328   ToolName = argv[0];
329   ToolType Tool = StringSwitch<ToolType>(sys::path::stem(ToolName))
330                       .EndsWith("strip", ToolType::Strip)
331                       .EndsWith("install-name-tool", ToolType::InstallNameTool)
332                       .EndsWith("install_name_tool", ToolType::InstallNameTool)
333                       .Default(ToolType::Objcopy);
334   // Expand response files.
335   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
336   // into a separate function in the CommandLine library and call that function
337   // here. This is duplicated code.
338   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
339   BumpPtrAllocator A;
340   StringSaver Saver(A);
341   cl::ExpandResponseFiles(Saver,
342                           Triple(sys::getProcessTriple()).isOSWindows()
343                               ? cl::TokenizeWindowsCommandLine
344                               : cl::TokenizeGNUCommandLine,
345                           NewArgv);
346 
347   auto Args = makeArrayRef(NewArgv).drop_front();
348   Expected<DriverConfig> DriverConfig =
349       (Tool == ToolType::Strip) ? parseStripOptions(Args, reportWarning)
350                                 : ((Tool == ToolType::InstallNameTool)
351                                        ? parseInstallNameToolOptions(Args)
352                                        : parseObjcopyOptions(Args, reportWarning));
353   if (!DriverConfig) {
354     logAllUnhandledErrors(DriverConfig.takeError(),
355                           WithColor::error(errs(), ToolName));
356     return 1;
357   }
358   for (CopyConfig &CopyConfig : DriverConfig->CopyConfigs) {
359     if (Error E = executeObjcopy(CopyConfig)) {
360       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
361       return 1;
362     }
363   }
364 
365   return 0;
366 }
367