xref: /llvm-project/llvm/tools/llvm-objcopy/llvm-objcopy.cpp (revision 94fba14f97233f77f30ded2fc3c2bfca9f2ce6fe) 
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 "ObjcopyOptions.h"
10 #include "llvm/ADT/STLExtras.h"
11 #include "llvm/ADT/SmallVector.h"
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/ADT/Twine.h"
14 #include "llvm/BinaryFormat/ELF.h"
15 #include "llvm/ObjCopy/COFF/COFFConfig.h"
16 #include "llvm/ObjCopy/COFF/COFFObjcopy.h"
17 #include "llvm/ObjCopy/CommonConfig.h"
18 #include "llvm/ObjCopy/ELF/ELFConfig.h"
19 #include "llvm/ObjCopy/ELF/ELFObjcopy.h"
20 #include "llvm/ObjCopy/MachO/MachOConfig.h"
21 #include "llvm/ObjCopy/MachO/MachOObjcopy.h"
22 #include "llvm/ObjCopy/ObjCopy.h"
23 #include "llvm/ObjCopy/wasm/WasmConfig.h"
24 #include "llvm/ObjCopy/wasm/WasmObjcopy.h"
25 #include "llvm/Object/Archive.h"
26 #include "llvm/Object/ArchiveWriter.h"
27 #include "llvm/Object/Binary.h"
28 #include "llvm/Object/COFF.h"
29 #include "llvm/Object/ELFObjectFile.h"
30 #include "llvm/Object/ELFTypes.h"
31 #include "llvm/Object/Error.h"
32 #include "llvm/Object/MachO.h"
33 #include "llvm/Object/MachOUniversal.h"
34 #include "llvm/Object/Wasm.h"
35 #include "llvm/Option/Arg.h"
36 #include "llvm/Option/ArgList.h"
37 #include "llvm/Option/Option.h"
38 #include "llvm/Support/Casting.h"
39 #include "llvm/Support/CommandLine.h"
40 #include "llvm/Support/Errc.h"
41 #include "llvm/Support/Error.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include "llvm/Support/ErrorOr.h"
44 #include "llvm/Support/Host.h"
45 #include "llvm/Support/InitLLVM.h"
46 #include "llvm/Support/Memory.h"
47 #include "llvm/Support/Path.h"
48 #include "llvm/Support/Process.h"
49 #include "llvm/Support/SmallVectorMemoryBuffer.h"
50 #include "llvm/Support/StringSaver.h"
51 #include "llvm/Support/WithColor.h"
52 #include "llvm/Support/raw_ostream.h"
53 #include <algorithm>
54 #include <cassert>
55 #include <cstdlib>
56 #include <memory>
57 #include <string>
58 #include <system_error>
59 #include <utility>
60 
61 using namespace llvm;
62 using namespace llvm::objcopy;
63 using namespace llvm::object;
64 
65 // The name this program was invoked as.
66 static StringRef ToolName;
67 
68 static ErrorSuccess reportWarning(Error E) {
69   assert(E);
70   WithColor::warning(errs(), ToolName) << toString(std::move(E)) << '\n';
71   return Error::success();
72 }
73 
74 static Expected<DriverConfig> getDriverConfig(ArrayRef<const char *> Args) {
75   StringRef Stem = sys::path::stem(ToolName);
76   auto Is = [=](StringRef Tool) {
77     // We need to recognize the following filenames:
78     //
79     // llvm-objcopy -> objcopy
80     // strip-10.exe -> strip
81     // powerpc64-unknown-freebsd13-objcopy -> objcopy
82     // llvm-install-name-tool -> install-name-tool
83     auto I = Stem.rfind_insensitive(Tool);
84     return I != StringRef::npos &&
85            (I + Tool.size() == Stem.size() || !isAlnum(Stem[I + Tool.size()]));
86   };
87 
88   if (Is("bitcode-strip") || Is("bitcode_strip"))
89     return parseBitcodeStripOptions(Args, reportWarning);
90   else if (Is("strip"))
91     return parseStripOptions(Args, reportWarning);
92   else if (Is("install-name-tool") || Is("install_name_tool"))
93     return parseInstallNameToolOptions(Args);
94   else
95     return parseObjcopyOptions(Args, reportWarning);
96 }
97 
98 /// The function executeObjcopyOnIHex does the dispatch based on the format
99 /// of the output specified by the command line options.
100 static Error executeObjcopyOnIHex(ConfigManager &ConfigMgr, MemoryBuffer &In,
101                                   raw_ostream &Out) {
102   // TODO: support output formats other than ELF.
103   Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
104   if (!ELFConfig)
105     return ELFConfig.takeError();
106 
107   return elf::executeObjcopyOnIHex(ConfigMgr.getCommonConfig(), *ELFConfig, In,
108                                    Out);
109 }
110 
111 /// The function executeObjcopyOnRawBinary does the dispatch based on the format
112 /// of the output specified by the command line options.
113 static Error executeObjcopyOnRawBinary(ConfigManager &ConfigMgr,
114                                        MemoryBuffer &In, raw_ostream &Out) {
115   const CommonConfig &Config = ConfigMgr.getCommonConfig();
116   switch (Config.OutputFormat) {
117   case FileFormat::ELF:
118   // FIXME: Currently, we call elf::executeObjcopyOnRawBinary even if the
119   // output format is binary/ihex or it's not given. This behavior differs from
120   // GNU objcopy. See https://bugs.llvm.org/show_bug.cgi?id=42171 for details.
121   case FileFormat::Binary:
122   case FileFormat::IHex:
123   case FileFormat::Unspecified:
124     Expected<const ELFConfig &> ELFConfig = ConfigMgr.getELFConfig();
125     if (!ELFConfig)
126       return ELFConfig.takeError();
127 
128     return elf::executeObjcopyOnRawBinary(Config, *ELFConfig, In, Out);
129   }
130 
131   llvm_unreachable("unsupported output format");
132 }
133 
134 static Error restoreStatOnFile(StringRef Filename,
135                                const sys::fs::file_status &Stat,
136                                const ConfigManager &ConfigMgr) {
137   int FD;
138   const CommonConfig &Config = ConfigMgr.getCommonConfig();
139 
140   // Writing to stdout should not be treated as an error here, just
141   // do not set access/modification times or permissions.
142   if (Filename == "-")
143     return Error::success();
144 
145   if (auto EC =
146           sys::fs::openFileForWrite(Filename, FD, sys::fs::CD_OpenExisting))
147     return createFileError(Filename, EC);
148 
149   if (Config.PreserveDates)
150     if (auto EC = sys::fs::setLastAccessAndModificationTime(
151             FD, Stat.getLastAccessedTime(), Stat.getLastModificationTime()))
152       return createFileError(Filename, EC);
153 
154   sys::fs::file_status OStat;
155   if (std::error_code EC = sys::fs::status(FD, OStat))
156     return createFileError(Filename, EC);
157   if (OStat.type() == sys::fs::file_type::regular_file) {
158 #ifndef _WIN32
159     // Keep ownership if llvm-objcopy is called under root.
160     if (Config.InputFilename == Config.OutputFilename && OStat.getUser() == 0)
161       sys::fs::changeFileOwnership(FD, Stat.getUser(), Stat.getGroup());
162 #endif
163 
164     sys::fs::perms Perm = Stat.permissions();
165     if (Config.InputFilename != Config.OutputFilename)
166       Perm = static_cast<sys::fs::perms>(Perm & ~sys::fs::getUmask() & ~06000);
167 #ifdef _WIN32
168     if (auto EC = sys::fs::setPermissions(Filename, Perm))
169 #else
170     if (auto EC = sys::fs::setPermissions(FD, Perm))
171 #endif
172       return createFileError(Filename, EC);
173   }
174 
175   if (auto EC = sys::Process::SafelyCloseFileDescriptor(FD))
176     return createFileError(Filename, EC);
177 
178   return Error::success();
179 }
180 
181 /// The function executeObjcopy does the higher level dispatch based on the type
182 /// of input (raw binary, archive or single object file) and takes care of the
183 /// format-agnostic modifications, i.e. preserving dates.
184 static Error executeObjcopy(ConfigManager &ConfigMgr) {
185   CommonConfig &Config = ConfigMgr.Common;
186 
187   sys::fs::file_status Stat;
188   if (Config.InputFilename != "-") {
189     if (auto EC = sys::fs::status(Config.InputFilename, Stat))
190       return createFileError(Config.InputFilename, EC);
191   } else {
192     Stat.permissions(static_cast<sys::fs::perms>(0777));
193   }
194 
195   std::function<Error(raw_ostream & OutFile)> ObjcopyFunc;
196 
197   OwningBinary<llvm::object::Binary> BinaryHolder;
198   std::unique_ptr<MemoryBuffer> MemoryBufferHolder;
199 
200   if (Config.InputFormat == FileFormat::Binary ||
201       Config.InputFormat == FileFormat::IHex) {
202     ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
203         MemoryBuffer::getFileOrSTDIN(Config.InputFilename);
204     if (!BufOrErr)
205       return createFileError(Config.InputFilename, BufOrErr.getError());
206     MemoryBufferHolder = std::move(*BufOrErr);
207 
208     if (Config.InputFormat == FileFormat::Binary)
209       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
210         // Handle FileFormat::Binary.
211         return executeObjcopyOnRawBinary(ConfigMgr, *MemoryBufferHolder,
212                                          OutFile);
213       };
214     else
215       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
216         // Handle FileFormat::IHex.
217         return executeObjcopyOnIHex(ConfigMgr, *MemoryBufferHolder, OutFile);
218       };
219   } else {
220     Expected<OwningBinary<llvm::object::Binary>> BinaryOrErr =
221         createBinary(Config.InputFilename);
222     if (!BinaryOrErr)
223       return createFileError(Config.InputFilename, BinaryOrErr.takeError());
224     BinaryHolder = std::move(*BinaryOrErr);
225 
226     if (Archive *Ar = dyn_cast<Archive>(BinaryHolder.getBinary())) {
227       // Handle Archive.
228       if (Error E = executeObjcopyOnArchive(ConfigMgr, *Ar))
229         return E;
230     } else {
231       // Handle llvm::object::Binary.
232       ObjcopyFunc = [&](raw_ostream &OutFile) -> Error {
233         return executeObjcopyOnBinary(ConfigMgr, *BinaryHolder.getBinary(),
234                                       OutFile);
235       };
236     }
237   }
238 
239   if (ObjcopyFunc) {
240     if (Config.SplitDWO.empty()) {
241       // Apply transformations described by Config and store result into
242       // Config.OutputFilename using specified ObjcopyFunc function.
243       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
244         return E;
245     } else {
246       Config.ExtractDWO = true;
247       Config.StripDWO = false;
248       // Copy .dwo tables from the Config.InputFilename into Config.SplitDWO
249       // file using specified ObjcopyFunc function.
250       if (Error E = writeToOutput(Config.SplitDWO, ObjcopyFunc))
251         return E;
252       Config.ExtractDWO = false;
253       Config.StripDWO = true;
254       // Apply transformations described by Config, remove .dwo tables and
255       // store result into Config.OutputFilename using specified ObjcopyFunc
256       // function.
257       if (Error E = writeToOutput(Config.OutputFilename, ObjcopyFunc))
258         return E;
259     }
260   }
261 
262   if (Error E = restoreStatOnFile(Config.OutputFilename, Stat, ConfigMgr))
263     return E;
264 
265   if (!Config.SplitDWO.empty()) {
266     Stat.permissions(static_cast<sys::fs::perms>(0666));
267     if (Error E = restoreStatOnFile(Config.SplitDWO, Stat, ConfigMgr))
268       return E;
269   }
270 
271   return Error::success();
272 }
273 
274 int main(int argc, char **argv) {
275   InitLLVM X(argc, argv);
276   ToolName = argv[0];
277 
278   // Expand response files.
279   // TODO: Move these lines, which are copied from lib/Support/CommandLine.cpp,
280   // into a separate function in the CommandLine library and call that function
281   // here. This is duplicated code.
282   SmallVector<const char *, 20> NewArgv(argv, argv + argc);
283   BumpPtrAllocator A;
284   StringSaver Saver(A);
285   cl::ExpandResponseFiles(Saver,
286                           Triple(sys::getProcessTriple()).isOSWindows()
287                               ? cl::TokenizeWindowsCommandLine
288                               : cl::TokenizeGNUCommandLine,
289                           NewArgv);
290 
291   auto Args = makeArrayRef(NewArgv).drop_front();
292   Expected<DriverConfig> DriverConfig = getDriverConfig(Args);
293 
294   if (!DriverConfig) {
295     logAllUnhandledErrors(DriverConfig.takeError(),
296                           WithColor::error(errs(), ToolName));
297     return 1;
298   }
299   for (ConfigManager &ConfigMgr : DriverConfig->CopyConfigs) {
300     if (Error E = executeObjcopy(ConfigMgr)) {
301       logAllUnhandledErrors(std::move(E), WithColor::error(errs(), ToolName));
302       return 1;
303     }
304   }
305 
306   return 0;
307 }
308