1 //===- DriverUtils.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 // This file contains utility functions for the driver. Because there
10 // are so many small functions, we created this separate file to make
11 // Driver.cpp less cluttered.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "COFFLinkerContext.h"
16 #include "Driver.h"
17 #include "Symbols.h"
18 #include "lld/Common/ErrorHandler.h"
19 #include "lld/Common/Memory.h"
20 #include "llvm/ADT/StringExtras.h"
21 #include "llvm/ADT/StringSwitch.h"
22 #include "llvm/BinaryFormat/COFF.h"
23 #include "llvm/IR/Mangler.h"
24 #include "llvm/Object/COFF.h"
25 #include "llvm/Object/WindowsResource.h"
26 #include "llvm/Option/Arg.h"
27 #include "llvm/Option/ArgList.h"
28 #include "llvm/Option/Option.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/MathExtras.h"
31 #include "llvm/Support/Process.h"
32 #include "llvm/Support/Program.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include "llvm/WindowsManifest/WindowsManifestMerger.h"
35 #include <memory>
36 #include <optional>
37
38 using namespace llvm::COFF;
39 using namespace llvm::object;
40 using namespace llvm::opt;
41 using namespace llvm;
42 using llvm::sys::Process;
43
44 namespace lld {
45 namespace coff {
46 namespace {
47
48 const uint16_t SUBLANG_ENGLISH_US = 0x0409;
49 const uint16_t RT_MANIFEST = 24;
50
51 class Executor {
52 public:
Executor(StringRef s)53 explicit Executor(StringRef s) : prog(saver().save(s)) {}
add(StringRef s)54 void add(StringRef s) { args.push_back(saver().save(s)); }
add(std::string & s)55 void add(std::string &s) { args.push_back(saver().save(s)); }
add(Twine s)56 void add(Twine s) { args.push_back(saver().save(s)); }
add(const char * s)57 void add(const char *s) { args.push_back(saver().save(s)); }
58
run()59 void run() {
60 ErrorOr<std::string> exeOrErr = sys::findProgramByName(prog);
61 if (auto ec = exeOrErr.getError())
62 fatal("unable to find " + prog + " in PATH: " + ec.message());
63 StringRef exe = saver().save(*exeOrErr);
64 args.insert(args.begin(), exe);
65
66 if (sys::ExecuteAndWait(args[0], args) != 0)
67 fatal("ExecuteAndWait failed: " +
68 llvm::join(args.begin(), args.end(), " "));
69 }
70
71 private:
72 StringRef prog;
73 std::vector<StringRef> args;
74 };
75
76 } // anonymous namespace
77
78 // Parses a string in the form of "<integer>[,<integer>]".
parseNumbers(StringRef arg,uint64_t * addr,uint64_t * size)79 void LinkerDriver::parseNumbers(StringRef arg, uint64_t *addr, uint64_t *size) {
80 auto [s1, s2] = arg.split(',');
81 if (s1.getAsInteger(0, *addr))
82 Fatal(ctx) << "invalid number: " << s1;
83 if (size && !s2.empty() && s2.getAsInteger(0, *size))
84 Fatal(ctx) << "invalid number: " << s2;
85 }
86
87 // Parses a string in the form of "<integer>[.<integer>]".
88 // If second number is not present, Minor is set to 0.
parseVersion(StringRef arg,uint32_t * major,uint32_t * minor)89 void LinkerDriver::parseVersion(StringRef arg, uint32_t *major,
90 uint32_t *minor) {
91 auto [s1, s2] = arg.split('.');
92 if (s1.getAsInteger(10, *major))
93 Fatal(ctx) << "invalid number: " << s1;
94 *minor = 0;
95 if (!s2.empty() && s2.getAsInteger(10, *minor))
96 Fatal(ctx) << "invalid number: " << s2;
97 }
98
parseGuard(StringRef fullArg)99 void LinkerDriver::parseGuard(StringRef fullArg) {
100 SmallVector<StringRef, 1> splitArgs;
101 fullArg.split(splitArgs, ",");
102 for (StringRef arg : splitArgs) {
103 if (arg.equals_insensitive("no"))
104 ctx.config.guardCF = GuardCFLevel::Off;
105 else if (arg.equals_insensitive("nolongjmp"))
106 ctx.config.guardCF &= ~GuardCFLevel::LongJmp;
107 else if (arg.equals_insensitive("noehcont"))
108 ctx.config.guardCF &= ~GuardCFLevel::EHCont;
109 else if (arg.equals_insensitive("cf") || arg.equals_insensitive("longjmp"))
110 ctx.config.guardCF |= GuardCFLevel::CF | GuardCFLevel::LongJmp;
111 else if (arg.equals_insensitive("ehcont"))
112 ctx.config.guardCF |= GuardCFLevel::CF | GuardCFLevel::EHCont;
113 else
114 Fatal(ctx) << "invalid argument to /guard: " << arg;
115 }
116 }
117
118 // Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
parseSubsystem(StringRef arg,WindowsSubsystem * sys,uint32_t * major,uint32_t * minor,bool * gotVersion)119 void LinkerDriver::parseSubsystem(StringRef arg, WindowsSubsystem *sys,
120 uint32_t *major, uint32_t *minor,
121 bool *gotVersion) {
122 auto [sysStr, ver] = arg.split(',');
123 std::string sysStrLower = sysStr.lower();
124 *sys = StringSwitch<WindowsSubsystem>(sysStrLower)
125 .Case("boot_application", IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION)
126 .Case("console", IMAGE_SUBSYSTEM_WINDOWS_CUI)
127 .Case("default", IMAGE_SUBSYSTEM_UNKNOWN)
128 .Case("efi_application", IMAGE_SUBSYSTEM_EFI_APPLICATION)
129 .Case("efi_boot_service_driver", IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER)
130 .Case("efi_rom", IMAGE_SUBSYSTEM_EFI_ROM)
131 .Case("efi_runtime_driver", IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER)
132 .Case("native", IMAGE_SUBSYSTEM_NATIVE)
133 .Case("posix", IMAGE_SUBSYSTEM_POSIX_CUI)
134 .Case("windows", IMAGE_SUBSYSTEM_WINDOWS_GUI)
135 .Default(IMAGE_SUBSYSTEM_UNKNOWN);
136 if (*sys == IMAGE_SUBSYSTEM_UNKNOWN && sysStrLower != "default")
137 Fatal(ctx) << "unknown subsystem: " << sysStr;
138 if (!ver.empty())
139 parseVersion(ver, major, minor);
140 if (gotVersion)
141 *gotVersion = !ver.empty();
142 }
143
144 // Parse a string of the form of "<from>=<to>".
145 // Results are directly written to Config.
parseMerge(StringRef s)146 void LinkerDriver::parseMerge(StringRef s) {
147 auto [from, to] = s.split('=');
148 if (from.empty() || to.empty())
149 Fatal(ctx) << "/merge: invalid argument: " << s;
150 if (from == ".rsrc" || to == ".rsrc")
151 Fatal(ctx) << "/merge: cannot merge '.rsrc' with any section";
152 if (from == ".reloc" || to == ".reloc")
153 Fatal(ctx) << "/merge: cannot merge '.reloc' with any section";
154 auto pair = ctx.config.merge.insert(std::make_pair(from, to));
155 bool inserted = pair.second;
156 if (!inserted) {
157 StringRef existing = pair.first->second;
158 if (existing != to)
159 Warn(ctx) << s << ": already merged into " << existing;
160 }
161 }
162
parsePDBPageSize(StringRef s)163 void LinkerDriver::parsePDBPageSize(StringRef s) {
164 int v;
165 if (s.getAsInteger(0, v)) {
166 Err(ctx) << "/pdbpagesize: invalid argument: " << s;
167 return;
168 }
169 if (v != 4096 && v != 8192 && v != 16384 && v != 32768) {
170 Err(ctx) << "/pdbpagesize: invalid argument: " << s;
171 return;
172 }
173
174 ctx.config.pdbPageSize = v;
175 }
176
parseSectionAttributes(COFFLinkerContext & ctx,StringRef s)177 static uint32_t parseSectionAttributes(COFFLinkerContext &ctx, StringRef s) {
178 uint32_t ret = 0;
179 for (char c : s.lower()) {
180 switch (c) {
181 case 'd':
182 ret |= IMAGE_SCN_MEM_DISCARDABLE;
183 break;
184 case 'e':
185 ret |= IMAGE_SCN_MEM_EXECUTE;
186 break;
187 case 'k':
188 ret |= IMAGE_SCN_MEM_NOT_CACHED;
189 break;
190 case 'p':
191 ret |= IMAGE_SCN_MEM_NOT_PAGED;
192 break;
193 case 'r':
194 ret |= IMAGE_SCN_MEM_READ;
195 break;
196 case 's':
197 ret |= IMAGE_SCN_MEM_SHARED;
198 break;
199 case 'w':
200 ret |= IMAGE_SCN_MEM_WRITE;
201 break;
202 default:
203 Fatal(ctx) << "/section: invalid argument: " << s;
204 }
205 }
206 return ret;
207 }
208
209 // Parses /section option argument.
parseSection(StringRef s)210 void LinkerDriver::parseSection(StringRef s) {
211 auto [name, attrs] = s.split(',');
212 if (name.empty() || attrs.empty())
213 Fatal(ctx) << "/section: invalid argument: " << s;
214 ctx.config.section[name] = parseSectionAttributes(ctx, attrs);
215 }
216
parseDosStub(StringRef path)217 void LinkerDriver::parseDosStub(StringRef path) {
218 std::unique_ptr<MemoryBuffer> stub =
219 CHECK(MemoryBuffer::getFile(path), "could not open " + path);
220 size_t bufferSize = stub->getBufferSize();
221 const char *bufferStart = stub->getBufferStart();
222 // MS link.exe compatibility:
223 // 1. stub must be greater than or equal to 64 bytes
224 // 2. stub must start with a valid dos signature 'MZ'
225 if (bufferSize < 64)
226 Err(ctx) << "/stub: stub must be greater than or equal to 64 bytes: "
227 << path;
228 if (bufferStart[0] != 'M' || bufferStart[1] != 'Z')
229 Err(ctx) << "/stub: invalid DOS signature: " << path;
230 ctx.config.dosStub = std::move(stub);
231 }
232
233 // Parses /functionpadmin option argument.
parseFunctionPadMin(llvm::opt::Arg * a)234 void LinkerDriver::parseFunctionPadMin(llvm::opt::Arg *a) {
235 StringRef arg = a->getNumValues() ? a->getValue() : "";
236 if (!arg.empty()) {
237 // Optional padding in bytes is given.
238 if (arg.getAsInteger(0, ctx.config.functionPadMin))
239 Err(ctx) << "/functionpadmin: invalid argument: " << arg;
240 return;
241 }
242 // No optional argument given.
243 // Set default padding based on machine, similar to link.exe.
244 // There is no default padding for ARM platforms.
245 if (ctx.config.machine == I386) {
246 ctx.config.functionPadMin = 5;
247 } else if (ctx.config.machine == AMD64) {
248 ctx.config.functionPadMin = 6;
249 } else {
250 Err(ctx) << "/functionpadmin: invalid argument for this machine: " << arg;
251 }
252 }
253
254 // Parses /dependentloadflag option argument.
parseDependentLoadFlags(llvm::opt::Arg * a)255 void LinkerDriver::parseDependentLoadFlags(llvm::opt::Arg *a) {
256 StringRef arg = a->getNumValues() ? a->getValue() : "";
257 if (!arg.empty()) {
258 if (arg.getAsInteger(0, ctx.config.dependentLoadFlags))
259 Err(ctx) << "/dependentloadflag: invalid argument: " << arg;
260 return;
261 }
262 // MSVC linker reports error "no argument specified", although MSDN describes
263 // argument as optional.
264 Err(ctx) << "/dependentloadflag: no argument specified";
265 }
266
267 // Parses a string in the form of "EMBED[,=<integer>]|NO".
268 // Results are directly written to
269 // Config.
parseManifest(StringRef arg)270 void LinkerDriver::parseManifest(StringRef arg) {
271 if (arg.equals_insensitive("no")) {
272 ctx.config.manifest = Configuration::No;
273 return;
274 }
275 if (!arg.starts_with_insensitive("embed"))
276 Fatal(ctx) << "invalid option " << arg;
277 ctx.config.manifest = Configuration::Embed;
278 arg = arg.substr(strlen("embed"));
279 if (arg.empty())
280 return;
281 if (!arg.starts_with_insensitive(",id="))
282 Fatal(ctx) << "invalid option " << arg;
283 arg = arg.substr(strlen(",id="));
284 if (arg.getAsInteger(0, ctx.config.manifestID))
285 Fatal(ctx) << "invalid option " << arg;
286 }
287
288 // Parses a string in the form of "level=<string>|uiAccess=<string>|NO".
289 // Results are directly written to Config.
parseManifestUAC(StringRef arg)290 void LinkerDriver::parseManifestUAC(StringRef arg) {
291 if (arg.equals_insensitive("no")) {
292 ctx.config.manifestUAC = false;
293 return;
294 }
295 for (;;) {
296 arg = arg.ltrim();
297 if (arg.empty())
298 return;
299 if (arg.consume_front_insensitive("level=")) {
300 std::tie(ctx.config.manifestLevel, arg) = arg.split(" ");
301 continue;
302 }
303 if (arg.consume_front_insensitive("uiaccess=")) {
304 std::tie(ctx.config.manifestUIAccess, arg) = arg.split(" ");
305 continue;
306 }
307 Fatal(ctx) << "invalid option " << arg;
308 }
309 }
310
311 // Parses a string in the form of "cd|net[,(cd|net)]*"
312 // Results are directly written to Config.
parseSwaprun(StringRef arg)313 void LinkerDriver::parseSwaprun(StringRef arg) {
314 do {
315 auto [swaprun, newArg] = arg.split(',');
316 if (swaprun.equals_insensitive("cd"))
317 ctx.config.swaprunCD = true;
318 else if (swaprun.equals_insensitive("net"))
319 ctx.config.swaprunNet = true;
320 else if (swaprun.empty())
321 Err(ctx) << "/swaprun: missing argument";
322 else
323 Err(ctx) << "/swaprun: invalid argument: " << swaprun;
324 // To catch trailing commas, e.g. `/spawrun:cd,`
325 if (newArg.empty() && arg.ends_with(","))
326 Err(ctx) << "/swaprun: missing argument";
327 arg = newArg;
328 } while (!arg.empty());
329 }
330
331 // An RAII temporary file class that automatically removes a temporary file.
332 namespace {
333 class TemporaryFile {
334 public:
TemporaryFile(COFFLinkerContext & ctx,StringRef prefix,StringRef extn,StringRef contents="")335 TemporaryFile(COFFLinkerContext &ctx, StringRef prefix, StringRef extn,
336 StringRef contents = "")
337 : ctx(ctx) {
338 SmallString<128> s;
339 if (auto ec = sys::fs::createTemporaryFile("lld-" + prefix, extn, s))
340 Fatal(ctx) << "cannot create a temporary file: " << ec.message();
341 path = std::string(s);
342
343 if (!contents.empty()) {
344 std::error_code ec;
345 raw_fd_ostream os(path, ec, sys::fs::OF_None);
346 if (ec)
347 Fatal(ctx) << "failed to open " << path << ": " << ec.message();
348 os << contents;
349 }
350 }
351
TemporaryFile(TemporaryFile && obj)352 TemporaryFile(TemporaryFile &&obj) noexcept : ctx(obj.ctx) {
353 std::swap(path, obj.path);
354 }
355
~TemporaryFile()356 ~TemporaryFile() {
357 if (path.empty())
358 return;
359 if (sys::fs::remove(path))
360 Fatal(ctx) << "failed to remove " << path;
361 }
362
363 // Returns a memory buffer of this temporary file.
364 // Note that this function does not leave the file open,
365 // so it is safe to remove the file immediately after this function
366 // is called (you cannot remove an opened file on Windows.)
getMemoryBuffer()367 std::unique_ptr<MemoryBuffer> getMemoryBuffer() {
368 // IsVolatile=true forces MemoryBuffer to not use mmap().
369 return CHECK(MemoryBuffer::getFile(path, /*IsText=*/false,
370 /*RequiresNullTerminator=*/false,
371 /*IsVolatile=*/true),
372 "could not open " + path);
373 }
374
375 COFFLinkerContext &ctx;
376 std::string path;
377 };
378 }
379
createDefaultXml()380 std::string LinkerDriver::createDefaultXml() {
381 std::string ret;
382 raw_string_ostream os(ret);
383
384 // Emit the XML. Note that we do *not* verify that the XML attributes are
385 // syntactically correct. This is intentional for link.exe compatibility.
386 os << "<?xml version=\"1.0\" standalone=\"yes\"?>\n"
387 << "<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\"\n"
388 << " manifestVersion=\"1.0\">\n";
389 if (ctx.config.manifestUAC) {
390 os << " <trustInfo xmlns=\"urn:schemas-microsoft-com:asm.v3\">\n"
391 << " <security>\n"
392 << " <requestedPrivileges>\n"
393 << " <requestedExecutionLevel level=" << ctx.config.manifestLevel
394 << " uiAccess=" << ctx.config.manifestUIAccess << "/>\n"
395 << " </requestedPrivileges>\n"
396 << " </security>\n"
397 << " </trustInfo>\n";
398 }
399 for (auto manifestDependency : ctx.config.manifestDependencies) {
400 os << " <dependency>\n"
401 << " <dependentAssembly>\n"
402 << " <assemblyIdentity " << manifestDependency << " />\n"
403 << " </dependentAssembly>\n"
404 << " </dependency>\n";
405 }
406 os << "</assembly>\n";
407 return ret;
408 }
409
410 std::string
createManifestXmlWithInternalMt(StringRef defaultXml)411 LinkerDriver::createManifestXmlWithInternalMt(StringRef defaultXml) {
412 std::unique_ptr<MemoryBuffer> defaultXmlCopy =
413 MemoryBuffer::getMemBufferCopy(defaultXml);
414
415 windows_manifest::WindowsManifestMerger merger;
416 if (auto e = merger.merge(*defaultXmlCopy))
417 Fatal(ctx) << "internal manifest tool failed on default xml: "
418 << toString(std::move(e));
419
420 for (StringRef filename : ctx.config.manifestInput) {
421 std::unique_ptr<MemoryBuffer> manifest =
422 check(MemoryBuffer::getFile(filename));
423 // Call takeBuffer to include in /reproduce: output if applicable.
424 if (auto e = merger.merge(takeBuffer(std::move(manifest))))
425 Fatal(ctx) << "internal manifest tool failed on file " << filename << ": "
426 << toString(std::move(e));
427 }
428
429 return std::string(merger.getMergedManifest()->getBuffer());
430 }
431
432 std::string
createManifestXmlWithExternalMt(StringRef defaultXml)433 LinkerDriver::createManifestXmlWithExternalMt(StringRef defaultXml) {
434 // Create the default manifest file as a temporary file.
435 TemporaryFile Default(ctx, "defaultxml", "manifest");
436 std::error_code ec;
437 raw_fd_ostream os(Default.path, ec, sys::fs::OF_TextWithCRLF);
438 if (ec)
439 Fatal(ctx) << "failed to open " << Default.path << ": " << ec.message();
440 os << defaultXml;
441 os.close();
442
443 // Merge user-supplied manifests if they are given. Since libxml2 is not
444 // enabled, we must shell out to Microsoft's mt.exe tool.
445 TemporaryFile user(ctx, "user", "manifest");
446
447 Executor e("mt.exe");
448 e.add("/manifest");
449 e.add(Default.path);
450 for (StringRef filename : ctx.config.manifestInput) {
451 e.add("/manifest");
452 e.add(filename);
453
454 // Manually add the file to the /reproduce: tar if needed.
455 if (tar)
456 if (auto mbOrErr = MemoryBuffer::getFile(filename))
457 takeBuffer(std::move(*mbOrErr));
458 }
459 e.add("/nologo");
460 e.add("/out:" + StringRef(user.path));
461 e.run();
462
463 return std::string(
464 CHECK(MemoryBuffer::getFile(user.path), "could not open " + user.path)
465 .get()
466 ->getBuffer());
467 }
468
createManifestXml()469 std::string LinkerDriver::createManifestXml() {
470 std::string defaultXml = createDefaultXml();
471 if (ctx.config.manifestInput.empty())
472 return defaultXml;
473
474 if (windows_manifest::isAvailable())
475 return createManifestXmlWithInternalMt(defaultXml);
476
477 return createManifestXmlWithExternalMt(defaultXml);
478 }
479
480 std::unique_ptr<WritableMemoryBuffer>
createMemoryBufferForManifestRes(size_t manifestSize)481 LinkerDriver::createMemoryBufferForManifestRes(size_t manifestSize) {
482 size_t resSize = alignTo(
483 object::WIN_RES_MAGIC_SIZE + object::WIN_RES_NULL_ENTRY_SIZE +
484 sizeof(object::WinResHeaderPrefix) + sizeof(object::WinResIDs) +
485 sizeof(object::WinResHeaderSuffix) + manifestSize,
486 object::WIN_RES_DATA_ALIGNMENT);
487 return WritableMemoryBuffer::getNewMemBuffer(resSize, ctx.config.outputFile +
488 ".manifest.res");
489 }
490
writeResFileHeader(char * & buf)491 static void writeResFileHeader(char *&buf) {
492 memcpy(buf, COFF::WinResMagic, sizeof(COFF::WinResMagic));
493 buf += sizeof(COFF::WinResMagic);
494 memset(buf, 0, object::WIN_RES_NULL_ENTRY_SIZE);
495 buf += object::WIN_RES_NULL_ENTRY_SIZE;
496 }
497
writeResEntryHeader(char * & buf,size_t manifestSize,int manifestID)498 static void writeResEntryHeader(char *&buf, size_t manifestSize,
499 int manifestID) {
500 // Write the prefix.
501 auto *prefix = reinterpret_cast<object::WinResHeaderPrefix *>(buf);
502 prefix->DataSize = manifestSize;
503 prefix->HeaderSize = sizeof(object::WinResHeaderPrefix) +
504 sizeof(object::WinResIDs) +
505 sizeof(object::WinResHeaderSuffix);
506 buf += sizeof(object::WinResHeaderPrefix);
507
508 // Write the Type/Name IDs.
509 auto *iDs = reinterpret_cast<object::WinResIDs *>(buf);
510 iDs->setType(RT_MANIFEST);
511 iDs->setName(manifestID);
512 buf += sizeof(object::WinResIDs);
513
514 // Write the suffix.
515 auto *suffix = reinterpret_cast<object::WinResHeaderSuffix *>(buf);
516 suffix->DataVersion = 0;
517 suffix->MemoryFlags = object::WIN_RES_PURE_MOVEABLE;
518 suffix->Language = SUBLANG_ENGLISH_US;
519 suffix->Version = 0;
520 suffix->Characteristics = 0;
521 buf += sizeof(object::WinResHeaderSuffix);
522 }
523
524 // Create a resource file containing a manifest XML.
createManifestRes()525 std::unique_ptr<MemoryBuffer> LinkerDriver::createManifestRes() {
526 std::string manifest = createManifestXml();
527
528 std::unique_ptr<WritableMemoryBuffer> res =
529 createMemoryBufferForManifestRes(manifest.size());
530
531 char *buf = res->getBufferStart();
532 writeResFileHeader(buf);
533 writeResEntryHeader(buf, manifest.size(), ctx.config.manifestID);
534
535 // Copy the manifest data into the .res file.
536 std::copy(manifest.begin(), manifest.end(), buf);
537 return std::move(res);
538 }
539
createSideBySideManifest()540 void LinkerDriver::createSideBySideManifest() {
541 std::string path = std::string(ctx.config.manifestFile);
542 if (path == "")
543 path = ctx.config.outputFile + ".manifest";
544 std::error_code ec;
545 raw_fd_ostream out(path, ec, sys::fs::OF_TextWithCRLF);
546 if (ec)
547 Fatal(ctx) << "failed to create manifest: " << ec.message();
548 out << createManifestXml();
549 }
550
551 // Parse a string in the form of
552 // "<name>[=<internalname>][,@ordinal[,NONAME]][,DATA][,PRIVATE]"
553 // or "<name>=<dllname>.<name>".
554 // Used for parsing /export arguments.
parseExport(StringRef arg)555 Export LinkerDriver::parseExport(StringRef arg) {
556 Export e;
557 e.source = ExportSource::Export;
558
559 StringRef rest;
560 std::tie(e.name, rest) = arg.split(",");
561 if (e.name.empty())
562 goto err;
563
564 if (e.name.contains('=')) {
565 auto [x, y] = e.name.split("=");
566
567 // If "<name>=<dllname>.<name>".
568 if (y.contains(".")) {
569 e.name = x;
570 e.forwardTo = y;
571 } else {
572 e.extName = x;
573 e.name = y;
574 if (e.name.empty())
575 goto err;
576 }
577 }
578
579 // Optional parameters
580 // "[,@ordinal[,NONAME]][,DATA][,PRIVATE][,EXPORTAS,exportname]"
581 while (!rest.empty()) {
582 StringRef tok;
583 std::tie(tok, rest) = rest.split(",");
584 if (tok.equals_insensitive("noname")) {
585 if (e.ordinal == 0)
586 goto err;
587 e.noname = true;
588 continue;
589 }
590 if (tok.equals_insensitive("data")) {
591 e.data = true;
592 continue;
593 }
594 if (tok.equals_insensitive("constant")) {
595 e.constant = true;
596 continue;
597 }
598 if (tok.equals_insensitive("private")) {
599 e.isPrivate = true;
600 continue;
601 }
602 if (tok.equals_insensitive("exportas")) {
603 if (!rest.empty() && !rest.contains(','))
604 e.exportAs = rest;
605 else
606 Err(ctx) << "invalid EXPORTAS value: " << rest;
607 break;
608 }
609 if (tok.starts_with("@")) {
610 int32_t ord;
611 if (tok.substr(1).getAsInteger(0, ord))
612 goto err;
613 if (ord <= 0 || 65535 < ord)
614 goto err;
615 e.ordinal = ord;
616 continue;
617 }
618 goto err;
619 }
620 return e;
621
622 err:
623 Fatal(ctx) << "invalid /export: " << arg;
624 llvm_unreachable("");
625 }
626
627 // Parses a string in the form of "key=value" and check
628 // if value matches previous values for the same key.
checkFailIfMismatch(StringRef arg,InputFile * source)629 void LinkerDriver::checkFailIfMismatch(StringRef arg, InputFile *source) {
630 auto [k, v] = arg.split('=');
631 if (k.empty() || v.empty())
632 Fatal(ctx) << "/failifmismatch: invalid argument: " << arg;
633 std::pair<StringRef, InputFile *> existing = ctx.config.mustMatch[k];
634 if (!existing.first.empty() && v != existing.first) {
635 std::string sourceStr = source ? toString(source) : "cmd-line";
636 std::string existingStr =
637 existing.second ? toString(existing.second) : "cmd-line";
638 Fatal(ctx) << "/failifmismatch: mismatch detected for '" << k << "':\n>>> "
639 << existingStr << " has value " << existing.first << "\n>>> "
640 << sourceStr << " has value " << v;
641 }
642 ctx.config.mustMatch[k] = {v, source};
643 }
644
645 // Convert Windows resource files (.res files) to a .obj file.
646 // Does what cvtres.exe does, but in-process and cross-platform.
convertResToCOFF(ArrayRef<MemoryBufferRef> mbs,ArrayRef<ObjFile * > objs)647 MemoryBufferRef LinkerDriver::convertResToCOFF(ArrayRef<MemoryBufferRef> mbs,
648 ArrayRef<ObjFile *> objs) {
649 object::WindowsResourceParser parser(/* MinGW */ ctx.config.mingw);
650
651 std::vector<std::string> duplicates;
652 for (MemoryBufferRef mb : mbs) {
653 std::unique_ptr<object::Binary> bin = check(object::createBinary(mb));
654 object::WindowsResource *rf = dyn_cast<object::WindowsResource>(bin.get());
655 if (!rf)
656 Fatal(ctx) << "cannot compile non-resource file as resource";
657
658 if (auto ec = parser.parse(rf, duplicates))
659 Fatal(ctx) << toString(std::move(ec));
660 }
661
662 // Note: This processes all .res files before all objs. Ideally they'd be
663 // handled in the same order they were linked (to keep the right one, if
664 // there are duplicates that are tolerated due to forceMultipleRes).
665 for (ObjFile *f : objs) {
666 object::ResourceSectionRef rsf;
667 if (auto ec = rsf.load(f->getCOFFObj()))
668 Fatal(ctx) << toString(f) << ": " << toString(std::move(ec));
669
670 if (auto ec = parser.parse(rsf, f->getName(), duplicates))
671 Fatal(ctx) << toString(std::move(ec));
672 }
673
674 if (ctx.config.mingw)
675 parser.cleanUpManifests(duplicates);
676
677 for (const auto &dupeDiag : duplicates)
678 if (ctx.config.forceMultipleRes)
679 Warn(ctx) << dupeDiag;
680 else
681 Err(ctx) << dupeDiag;
682
683 Expected<std::unique_ptr<MemoryBuffer>> e =
684 llvm::object::writeWindowsResourceCOFF(ctx.config.machine, parser,
685 ctx.config.timestamp);
686 if (!e)
687 Fatal(ctx) << "failed to write .res to COFF: " << toString(e.takeError());
688
689 MemoryBufferRef mbref = **e;
690 make<std::unique_ptr<MemoryBuffer>>(std::move(*e)); // take ownership
691 return mbref;
692 }
693
694 // Create OptTable
695
696 #define OPTTABLE_STR_TABLE_CODE
697 #include "Options.inc"
698 #undef OPTTABLE_STR_TABLE_CODE
699
700 // Create prefix string literals used in Options.td
701 #define OPTTABLE_PREFIXES_TABLE_CODE
702 #include "Options.inc"
703 #undef OPTTABLE_PREFIXES_TABLE_CODE
704
705 // Create table mapping all options defined in Options.td
706 static constexpr llvm::opt::OptTable::Info infoTable[] = {
707 #define OPTION(...) LLVM_CONSTRUCT_OPT_INFO(__VA_ARGS__),
708 #include "Options.inc"
709 #undef OPTION
710 };
711
COFFOptTable()712 COFFOptTable::COFFOptTable()
713 : GenericOptTable(OptionStrTable, OptionPrefixesTable, infoTable, true) {}
714
715 // Set color diagnostics according to --color-diagnostics={auto,always,never}
716 // or --no-color-diagnostics flags.
handleColorDiagnostics(COFFLinkerContext & ctx,opt::InputArgList & args)717 static void handleColorDiagnostics(COFFLinkerContext &ctx,
718 opt::InputArgList &args) {
719 auto *arg = args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
720 OPT_no_color_diagnostics);
721 if (!arg)
722 return;
723 if (arg->getOption().getID() == OPT_color_diagnostics) {
724 ctx.e.errs().enable_colors(true);
725 } else if (arg->getOption().getID() == OPT_no_color_diagnostics) {
726 ctx.e.errs().enable_colors(false);
727 } else {
728 StringRef s = arg->getValue();
729 if (s == "always")
730 ctx.e.errs().enable_colors(true);
731 else if (s == "never")
732 ctx.e.errs().enable_colors(false);
733 else if (s != "auto")
734 Err(ctx) << "unknown option: --color-diagnostics=" << s;
735 }
736 }
737
getQuotingStyle(COFFLinkerContext & ctx,opt::InputArgList & args)738 static cl::TokenizerCallback getQuotingStyle(COFFLinkerContext &ctx,
739 opt::InputArgList &args) {
740 if (auto *arg = args.getLastArg(OPT_rsp_quoting)) {
741 StringRef s = arg->getValue();
742 if (s != "windows" && s != "posix")
743 Err(ctx) << "invalid response file quoting: " << s;
744 if (s == "windows")
745 return cl::TokenizeWindowsCommandLine;
746 return cl::TokenizeGNUCommandLine;
747 }
748 // The COFF linker always defaults to Windows quoting.
749 return cl::TokenizeWindowsCommandLine;
750 }
751
ArgParser(COFFLinkerContext & c)752 ArgParser::ArgParser(COFFLinkerContext &c) : ctx(c) {}
753
754 // Parses a given list of options.
parse(ArrayRef<const char * > argv)755 opt::InputArgList ArgParser::parse(ArrayRef<const char *> argv) {
756 // Make InputArgList from string vectors.
757 unsigned missingIndex;
758 unsigned missingCount;
759
760 // We need to get the quoting style for response files before parsing all
761 // options so we parse here before and ignore all the options but
762 // --rsp-quoting and /lldignoreenv.
763 // (This means --rsp-quoting can't be added through %LINK%.)
764 opt::InputArgList args =
765 ctx.optTable.ParseArgs(argv, missingIndex, missingCount);
766
767 // Expand response files (arguments in the form of @<filename>) and insert
768 // flags from %LINK% and %_LINK_%, and then parse the argument again.
769 SmallVector<const char *, 256> expandedArgv(argv.data(),
770 argv.data() + argv.size());
771 if (!args.hasArg(OPT_lldignoreenv))
772 addLINK(expandedArgv);
773 cl::ExpandResponseFiles(saver(), getQuotingStyle(ctx, args), expandedArgv);
774 args = ctx.optTable.ParseArgs(ArrayRef(expandedArgv).drop_front(),
775 missingIndex, missingCount);
776
777 // Print the real command line if response files are expanded.
778 if (args.hasArg(OPT_verbose) && argv.size() != expandedArgv.size()) {
779 std::string msg = "Command line:";
780 for (const char *s : expandedArgv)
781 msg += " " + std::string(s);
782 Msg(ctx) << msg;
783 }
784
785 // Save the command line after response file expansion so we can write it to
786 // the PDB if necessary. Mimic MSVC, which skips input files.
787 ctx.config.argv = {argv[0]};
788 for (opt::Arg *arg : args) {
789 if (arg->getOption().getKind() != opt::Option::InputClass) {
790 ctx.config.argv.emplace_back(args.getArgString(arg->getIndex()));
791 }
792 }
793
794 // Handle /WX early since it converts missing argument warnings to errors.
795 ctx.e.fatalWarnings = args.hasFlag(OPT_WX, OPT_WX_no, false);
796
797 if (missingCount)
798 Fatal(ctx) << args.getArgString(missingIndex) << ": missing argument";
799
800 handleColorDiagnostics(ctx, args);
801
802 for (opt::Arg *arg : args.filtered(OPT_UNKNOWN)) {
803 std::string nearest;
804 if (ctx.optTable.findNearest(arg->getAsString(args), nearest) > 1)
805 Warn(ctx) << "ignoring unknown argument '" << arg->getAsString(args)
806 << "'";
807 else
808 Warn(ctx) << "ignoring unknown argument '" << arg->getAsString(args)
809 << "', did you mean '" << nearest << "'";
810 }
811
812 if (args.hasArg(OPT_lib))
813 Warn(ctx) << "ignoring /lib since it's not the first argument";
814
815 return args;
816 }
817
818 // Tokenizes and parses a given string as command line in .drective section.
parseDirectives(StringRef s)819 ParsedDirectives ArgParser::parseDirectives(StringRef s) {
820 ParsedDirectives result;
821 SmallVector<const char *, 16> rest;
822
823 // Handle /EXPORT and /INCLUDE in a fast path. These directives can appear for
824 // potentially every symbol in the object, so they must be handled quickly.
825 SmallVector<StringRef, 16> tokens;
826 cl::TokenizeWindowsCommandLineNoCopy(s, saver(), tokens);
827 for (StringRef tok : tokens) {
828 if (tok.starts_with_insensitive("/export:") ||
829 tok.starts_with_insensitive("-export:"))
830 result.exports.push_back(tok.substr(strlen("/export:")));
831 else if (tok.starts_with_insensitive("/include:") ||
832 tok.starts_with_insensitive("-include:"))
833 result.includes.push_back(tok.substr(strlen("/include:")));
834 else if (tok.starts_with_insensitive("/exclude-symbols:") ||
835 tok.starts_with_insensitive("-exclude-symbols:"))
836 result.excludes.push_back(tok.substr(strlen("/exclude-symbols:")));
837 else {
838 // Copy substrings that are not valid C strings. The tokenizer may have
839 // already copied quoted arguments for us, so those do not need to be
840 // copied again.
841 bool HasNul = tok.end() != s.end() && tok.data()[tok.size()] == '\0';
842 rest.push_back(HasNul ? tok.data() : saver().save(tok).data());
843 }
844 }
845
846 // Make InputArgList from unparsed string vectors.
847 unsigned missingIndex;
848 unsigned missingCount;
849
850 result.args = ctx.optTable.ParseArgs(rest, missingIndex, missingCount);
851
852 if (missingCount)
853 Fatal(ctx) << result.args.getArgString(missingIndex)
854 << ": missing argument";
855 for (auto *arg : result.args.filtered(OPT_UNKNOWN))
856 Warn(ctx) << "ignoring unknown argument: " << arg->getAsString(result.args);
857 return result;
858 }
859
860 // link.exe has an interesting feature. If LINK or _LINK_ environment
861 // variables exist, their contents are handled as command line strings.
862 // So you can pass extra arguments using them.
addLINK(SmallVector<const char *,256> & argv)863 void ArgParser::addLINK(SmallVector<const char *, 256> &argv) {
864 // Concatenate LINK env and command line arguments, and then parse them.
865 if (std::optional<std::string> s = Process::GetEnv("LINK")) {
866 std::vector<const char *> v = tokenize(*s);
867 argv.insert(std::next(argv.begin()), v.begin(), v.end());
868 }
869 if (std::optional<std::string> s = Process::GetEnv("_LINK_")) {
870 std::vector<const char *> v = tokenize(*s);
871 argv.insert(std::next(argv.begin()), v.begin(), v.end());
872 }
873 }
874
tokenize(StringRef s)875 std::vector<const char *> ArgParser::tokenize(StringRef s) {
876 SmallVector<const char *, 16> tokens;
877 cl::TokenizeWindowsCommandLine(s, saver(), tokens);
878 return std::vector<const char *>(tokens.begin(), tokens.end());
879 }
880
printHelp(const char * argv0)881 void LinkerDriver::printHelp(const char *argv0) {
882 ctx.optTable.printHelp(ctx.e.outs(),
883 (std::string(argv0) + " [options] file...").c_str(),
884 "LLVM Linker", false);
885 }
886
887 } // namespace coff
888 } // namespace lld
889