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 "Config.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/Optional.h"
21 #include "llvm/ADT/StringSwitch.h"
22 #include "llvm/BinaryFormat/COFF.h"
23 #include "llvm/Object/COFF.h"
24 #include "llvm/Object/WindowsResource.h"
25 #include "llvm/Option/Arg.h"
26 #include "llvm/Option/ArgList.h"
27 #include "llvm/Option/Option.h"
28 #include "llvm/Support/CommandLine.h"
29 #include "llvm/Support/FileUtilities.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 <limits>
36 #include <memory>
37
38 using namespace llvm::COFF;
39 using namespace llvm;
40 using llvm::sys::Process;
41
42 namespace lld {
43 namespace coff {
44 namespace {
45
46 const uint16_t SUBLANG_ENGLISH_US = 0x0409;
47 const uint16_t RT_MANIFEST = 24;
48
49 class Executor {
50 public:
Executor(StringRef s)51 explicit Executor(StringRef s) : prog(saver.save(s)) {}
add(StringRef s)52 void add(StringRef s) { args.push_back(saver.save(s)); }
add(std::string & s)53 void add(std::string &s) { args.push_back(saver.save(s)); }
add(Twine s)54 void add(Twine s) { args.push_back(saver.save(s)); }
add(const char * s)55 void add(const char *s) { args.push_back(saver.save(s)); }
56
run()57 void run() {
58 ErrorOr<std::string> exeOrErr = sys::findProgramByName(prog);
59 if (auto ec = exeOrErr.getError())
60 fatal("unable to find " + prog + " in PATH: " + ec.message());
61 StringRef exe = saver.save(*exeOrErr);
62 args.insert(args.begin(), exe);
63
64 if (sys::ExecuteAndWait(args[0], args) != 0)
65 fatal("ExecuteAndWait failed: " +
66 llvm::join(args.begin(), args.end(), " "));
67 }
68
69 private:
70 StringRef prog;
71 std::vector<StringRef> args;
72 };
73
74 } // anonymous namespace
75
76 // Parses a string in the form of "<integer>[,<integer>]".
parseNumbers(StringRef arg,uint64_t * addr,uint64_t * size)77 void parseNumbers(StringRef arg, uint64_t *addr, uint64_t *size) {
78 StringRef s1, s2;
79 std::tie(s1, s2) = arg.split(',');
80 if (s1.getAsInteger(0, *addr))
81 fatal("invalid number: " + s1);
82 if (size && !s2.empty() && s2.getAsInteger(0, *size))
83 fatal("invalid number: " + s2);
84 }
85
86 // Parses a string in the form of "<integer>[.<integer>]".
87 // If second number is not present, Minor is set to 0.
parseVersion(StringRef arg,uint32_t * major,uint32_t * minor)88 void parseVersion(StringRef arg, uint32_t *major, uint32_t *minor) {
89 StringRef s1, s2;
90 std::tie(s1, s2) = arg.split('.');
91 if (s1.getAsInteger(10, *major))
92 fatal("invalid number: " + s1);
93 *minor = 0;
94 if (!s2.empty() && s2.getAsInteger(10, *minor))
95 fatal("invalid number: " + s2);
96 }
97
parseGuard(StringRef fullArg)98 void parseGuard(StringRef fullArg) {
99 SmallVector<StringRef, 1> splitArgs;
100 fullArg.split(splitArgs, ",");
101 for (StringRef arg : splitArgs) {
102 if (arg.equals_lower("no"))
103 config->guardCF = GuardCFLevel::Off;
104 else if (arg.equals_lower("nolongjmp"))
105 config->guardCF = GuardCFLevel::NoLongJmp;
106 else if (arg.equals_lower("cf") || arg.equals_lower("longjmp"))
107 config->guardCF = GuardCFLevel::Full;
108 else
109 fatal("invalid argument to /guard: " + arg);
110 }
111 }
112
113 // Parses a string in the form of "<subsystem>[,<integer>[.<integer>]]".
parseSubsystem(StringRef arg,WindowsSubsystem * sys,uint32_t * major,uint32_t * minor,bool * gotVersion)114 void parseSubsystem(StringRef arg, WindowsSubsystem *sys, uint32_t *major,
115 uint32_t *minor, bool *gotVersion) {
116 StringRef sysStr, ver;
117 std::tie(sysStr, ver) = arg.split(',');
118 std::string sysStrLower = sysStr.lower();
119 *sys = StringSwitch<WindowsSubsystem>(sysStrLower)
120 .Case("boot_application", IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION)
121 .Case("console", IMAGE_SUBSYSTEM_WINDOWS_CUI)
122 .Case("default", IMAGE_SUBSYSTEM_UNKNOWN)
123 .Case("efi_application", IMAGE_SUBSYSTEM_EFI_APPLICATION)
124 .Case("efi_boot_service_driver", IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER)
125 .Case("efi_rom", IMAGE_SUBSYSTEM_EFI_ROM)
126 .Case("efi_runtime_driver", IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER)
127 .Case("native", IMAGE_SUBSYSTEM_NATIVE)
128 .Case("posix", IMAGE_SUBSYSTEM_POSIX_CUI)
129 .Case("windows", IMAGE_SUBSYSTEM_WINDOWS_GUI)
130 .Default(IMAGE_SUBSYSTEM_UNKNOWN);
131 if (*sys == IMAGE_SUBSYSTEM_UNKNOWN && sysStrLower != "default")
132 fatal("unknown subsystem: " + sysStr);
133 if (!ver.empty())
134 parseVersion(ver, major, minor);
135 if (gotVersion)
136 *gotVersion = !ver.empty();
137 }
138
139 // Parse a string of the form of "<from>=<to>".
140 // Results are directly written to Config.
parseAlternateName(StringRef s)141 void parseAlternateName(StringRef s) {
142 StringRef from, to;
143 std::tie(from, to) = s.split('=');
144 if (from.empty() || to.empty())
145 fatal("/alternatename: invalid argument: " + s);
146 auto it = config->alternateNames.find(from);
147 if (it != config->alternateNames.end() && it->second != to)
148 fatal("/alternatename: conflicts: " + s);
149 config->alternateNames.insert(it, std::make_pair(from, to));
150 }
151
152 // Parse a string of the form of "<from>=<to>".
153 // Results are directly written to Config.
parseMerge(StringRef s)154 void parseMerge(StringRef s) {
155 StringRef from, to;
156 std::tie(from, to) = s.split('=');
157 if (from.empty() || to.empty())
158 fatal("/merge: invalid argument: " + s);
159 if (from == ".rsrc" || to == ".rsrc")
160 fatal("/merge: cannot merge '.rsrc' with any section");
161 if (from == ".reloc" || to == ".reloc")
162 fatal("/merge: cannot merge '.reloc' with any section");
163 auto pair = config->merge.insert(std::make_pair(from, to));
164 bool inserted = pair.second;
165 if (!inserted) {
166 StringRef existing = pair.first->second;
167 if (existing != to)
168 warn(s + ": already merged into " + existing);
169 }
170 }
171
parseSectionAttributes(StringRef s)172 static uint32_t parseSectionAttributes(StringRef s) {
173 uint32_t ret = 0;
174 for (char c : s.lower()) {
175 switch (c) {
176 case 'd':
177 ret |= IMAGE_SCN_MEM_DISCARDABLE;
178 break;
179 case 'e':
180 ret |= IMAGE_SCN_MEM_EXECUTE;
181 break;
182 case 'k':
183 ret |= IMAGE_SCN_MEM_NOT_CACHED;
184 break;
185 case 'p':
186 ret |= IMAGE_SCN_MEM_NOT_PAGED;
187 break;
188 case 'r':
189 ret |= IMAGE_SCN_MEM_READ;
190 break;
191 case 's':
192 ret |= IMAGE_SCN_MEM_SHARED;
193 break;
194 case 'w':
195 ret |= IMAGE_SCN_MEM_WRITE;
196 break;
197 default:
198 fatal("/section: invalid argument: " + s);
199 }
200 }
201 return ret;
202 }
203
204 // Parses /section option argument.
parseSection(StringRef s)205 void parseSection(StringRef s) {
206 StringRef name, attrs;
207 std::tie(name, attrs) = s.split(',');
208 if (name.empty() || attrs.empty())
209 fatal("/section: invalid argument: " + s);
210 config->section[name] = parseSectionAttributes(attrs);
211 }
212
213 // Parses /aligncomm option argument.
parseAligncomm(StringRef s)214 void parseAligncomm(StringRef s) {
215 StringRef name, align;
216 std::tie(name, align) = s.split(',');
217 if (name.empty() || align.empty()) {
218 error("/aligncomm: invalid argument: " + s);
219 return;
220 }
221 int v;
222 if (align.getAsInteger(0, v)) {
223 error("/aligncomm: invalid argument: " + s);
224 return;
225 }
226 config->alignComm[std::string(name)] =
227 std::max(config->alignComm[std::string(name)], 1 << v);
228 }
229
230 // Parses /functionpadmin option argument.
parseFunctionPadMin(llvm::opt::Arg * a,llvm::COFF::MachineTypes machine)231 void parseFunctionPadMin(llvm::opt::Arg *a, llvm::COFF::MachineTypes machine) {
232 StringRef arg = a->getNumValues() ? a->getValue() : "";
233 if (!arg.empty()) {
234 // Optional padding in bytes is given.
235 if (arg.getAsInteger(0, config->functionPadMin))
236 error("/functionpadmin: invalid argument: " + arg);
237 return;
238 }
239 // No optional argument given.
240 // Set default padding based on machine, similar to link.exe.
241 // There is no default padding for ARM platforms.
242 if (machine == I386) {
243 config->functionPadMin = 5;
244 } else if (machine == AMD64) {
245 config->functionPadMin = 6;
246 } else {
247 error("/functionpadmin: invalid argument for this machine: " + arg);
248 }
249 }
250
251 // Parses a string in the form of "EMBED[,=<integer>]|NO".
252 // Results are directly written to Config.
parseManifest(StringRef arg)253 void parseManifest(StringRef arg) {
254 if (arg.equals_lower("no")) {
255 config->manifest = Configuration::No;
256 return;
257 }
258 if (!arg.startswith_lower("embed"))
259 fatal("invalid option " + arg);
260 config->manifest = Configuration::Embed;
261 arg = arg.substr(strlen("embed"));
262 if (arg.empty())
263 return;
264 if (!arg.startswith_lower(",id="))
265 fatal("invalid option " + arg);
266 arg = arg.substr(strlen(",id="));
267 if (arg.getAsInteger(0, config->manifestID))
268 fatal("invalid option " + arg);
269 }
270
271 // Parses a string in the form of "level=<string>|uiAccess=<string>|NO".
272 // Results are directly written to Config.
parseManifestUAC(StringRef arg)273 void parseManifestUAC(StringRef arg) {
274 if (arg.equals_lower("no")) {
275 config->manifestUAC = false;
276 return;
277 }
278 for (;;) {
279 arg = arg.ltrim();
280 if (arg.empty())
281 return;
282 if (arg.startswith_lower("level=")) {
283 arg = arg.substr(strlen("level="));
284 std::tie(config->manifestLevel, arg) = arg.split(" ");
285 continue;
286 }
287 if (arg.startswith_lower("uiaccess=")) {
288 arg = arg.substr(strlen("uiaccess="));
289 std::tie(config->manifestUIAccess, arg) = arg.split(" ");
290 continue;
291 }
292 fatal("invalid option " + arg);
293 }
294 }
295
296 // Parses a string in the form of "cd|net[,(cd|net)]*"
297 // Results are directly written to Config.
parseSwaprun(StringRef arg)298 void parseSwaprun(StringRef arg) {
299 do {
300 StringRef swaprun, newArg;
301 std::tie(swaprun, newArg) = arg.split(',');
302 if (swaprun.equals_lower("cd"))
303 config->swaprunCD = true;
304 else if (swaprun.equals_lower("net"))
305 config->swaprunNet = true;
306 else if (swaprun.empty())
307 error("/swaprun: missing argument");
308 else
309 error("/swaprun: invalid argument: " + swaprun);
310 // To catch trailing commas, e.g. `/spawrun:cd,`
311 if (newArg.empty() && arg.endswith(","))
312 error("/swaprun: missing argument");
313 arg = newArg;
314 } while (!arg.empty());
315 }
316
317 // An RAII temporary file class that automatically removes a temporary file.
318 namespace {
319 class TemporaryFile {
320 public:
TemporaryFile(StringRef prefix,StringRef extn,StringRef contents="")321 TemporaryFile(StringRef prefix, StringRef extn, StringRef contents = "") {
322 SmallString<128> s;
323 if (auto ec = sys::fs::createTemporaryFile("lld-" + prefix, extn, s))
324 fatal("cannot create a temporary file: " + ec.message());
325 path = std::string(s.str());
326
327 if (!contents.empty()) {
328 std::error_code ec;
329 raw_fd_ostream os(path, ec, sys::fs::OF_None);
330 if (ec)
331 fatal("failed to open " + path + ": " + ec.message());
332 os << contents;
333 }
334 }
335
TemporaryFile(TemporaryFile && obj)336 TemporaryFile(TemporaryFile &&obj) {
337 std::swap(path, obj.path);
338 }
339
~TemporaryFile()340 ~TemporaryFile() {
341 if (path.empty())
342 return;
343 if (sys::fs::remove(path))
344 fatal("failed to remove " + path);
345 }
346
347 // Returns a memory buffer of this temporary file.
348 // Note that this function does not leave the file open,
349 // so it is safe to remove the file immediately after this function
350 // is called (you cannot remove an opened file on Windows.)
getMemoryBuffer()351 std::unique_ptr<MemoryBuffer> getMemoryBuffer() {
352 // IsVolatile=true forces MemoryBuffer to not use mmap().
353 return CHECK(MemoryBuffer::getFile(path, /*FileSize=*/-1,
354 /*RequiresNullTerminator=*/false,
355 /*IsVolatile=*/true),
356 "could not open " + path);
357 }
358
359 std::string path;
360 };
361 }
362
createDefaultXml()363 static std::string createDefaultXml() {
364 std::string ret;
365 raw_string_ostream os(ret);
366
367 // Emit the XML. Note that we do *not* verify that the XML attributes are
368 // syntactically correct. This is intentional for link.exe compatibility.
369 os << "<?xml version=\"1.0\" standalone=\"yes\"?>\n"
370 << "<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\"\n"
371 << " manifestVersion=\"1.0\">\n";
372 if (config->manifestUAC) {
373 os << " <trustInfo>\n"
374 << " <security>\n"
375 << " <requestedPrivileges>\n"
376 << " <requestedExecutionLevel level=" << config->manifestLevel
377 << " uiAccess=" << config->manifestUIAccess << "/>\n"
378 << " </requestedPrivileges>\n"
379 << " </security>\n"
380 << " </trustInfo>\n";
381 }
382 if (!config->manifestDependency.empty()) {
383 os << " <dependency>\n"
384 << " <dependentAssembly>\n"
385 << " <assemblyIdentity " << config->manifestDependency << " />\n"
386 << " </dependentAssembly>\n"
387 << " </dependency>\n";
388 }
389 os << "</assembly>\n";
390 return os.str();
391 }
392
createManifestXmlWithInternalMt(StringRef defaultXml)393 static std::string createManifestXmlWithInternalMt(StringRef defaultXml) {
394 std::unique_ptr<MemoryBuffer> defaultXmlCopy =
395 MemoryBuffer::getMemBufferCopy(defaultXml);
396
397 windows_manifest::WindowsManifestMerger merger;
398 if (auto e = merger.merge(*defaultXmlCopy.get()))
399 fatal("internal manifest tool failed on default xml: " +
400 toString(std::move(e)));
401
402 for (StringRef filename : config->manifestInput) {
403 std::unique_ptr<MemoryBuffer> manifest =
404 check(MemoryBuffer::getFile(filename));
405 if (auto e = merger.merge(*manifest.get()))
406 fatal("internal manifest tool failed on file " + filename + ": " +
407 toString(std::move(e)));
408 }
409
410 return std::string(merger.getMergedManifest().get()->getBuffer());
411 }
412
createManifestXmlWithExternalMt(StringRef defaultXml)413 static std::string createManifestXmlWithExternalMt(StringRef defaultXml) {
414 // Create the default manifest file as a temporary file.
415 TemporaryFile Default("defaultxml", "manifest");
416 std::error_code ec;
417 raw_fd_ostream os(Default.path, ec, sys::fs::OF_Text);
418 if (ec)
419 fatal("failed to open " + Default.path + ": " + ec.message());
420 os << defaultXml;
421 os.close();
422
423 // Merge user-supplied manifests if they are given. Since libxml2 is not
424 // enabled, we must shell out to Microsoft's mt.exe tool.
425 TemporaryFile user("user", "manifest");
426
427 Executor e("mt.exe");
428 e.add("/manifest");
429 e.add(Default.path);
430 for (StringRef filename : config->manifestInput) {
431 e.add("/manifest");
432 e.add(filename);
433 }
434 e.add("/nologo");
435 e.add("/out:" + StringRef(user.path));
436 e.run();
437
438 return std::string(
439 CHECK(MemoryBuffer::getFile(user.path), "could not open " + user.path)
440 .get()
441 ->getBuffer());
442 }
443
createManifestXml()444 static std::string createManifestXml() {
445 std::string defaultXml = createDefaultXml();
446 if (config->manifestInput.empty())
447 return defaultXml;
448
449 if (windows_manifest::isAvailable())
450 return createManifestXmlWithInternalMt(defaultXml);
451
452 return createManifestXmlWithExternalMt(defaultXml);
453 }
454
455 static std::unique_ptr<WritableMemoryBuffer>
createMemoryBufferForManifestRes(size_t manifestSize)456 createMemoryBufferForManifestRes(size_t manifestSize) {
457 size_t resSize = alignTo(
458 object::WIN_RES_MAGIC_SIZE + object::WIN_RES_NULL_ENTRY_SIZE +
459 sizeof(object::WinResHeaderPrefix) + sizeof(object::WinResIDs) +
460 sizeof(object::WinResHeaderSuffix) + manifestSize,
461 object::WIN_RES_DATA_ALIGNMENT);
462 return WritableMemoryBuffer::getNewMemBuffer(resSize, config->outputFile +
463 ".manifest.res");
464 }
465
writeResFileHeader(char * & buf)466 static void writeResFileHeader(char *&buf) {
467 memcpy(buf, COFF::WinResMagic, sizeof(COFF::WinResMagic));
468 buf += sizeof(COFF::WinResMagic);
469 memset(buf, 0, object::WIN_RES_NULL_ENTRY_SIZE);
470 buf += object::WIN_RES_NULL_ENTRY_SIZE;
471 }
472
writeResEntryHeader(char * & buf,size_t manifestSize)473 static void writeResEntryHeader(char *&buf, size_t manifestSize) {
474 // Write the prefix.
475 auto *prefix = reinterpret_cast<object::WinResHeaderPrefix *>(buf);
476 prefix->DataSize = manifestSize;
477 prefix->HeaderSize = sizeof(object::WinResHeaderPrefix) +
478 sizeof(object::WinResIDs) +
479 sizeof(object::WinResHeaderSuffix);
480 buf += sizeof(object::WinResHeaderPrefix);
481
482 // Write the Type/Name IDs.
483 auto *iDs = reinterpret_cast<object::WinResIDs *>(buf);
484 iDs->setType(RT_MANIFEST);
485 iDs->setName(config->manifestID);
486 buf += sizeof(object::WinResIDs);
487
488 // Write the suffix.
489 auto *suffix = reinterpret_cast<object::WinResHeaderSuffix *>(buf);
490 suffix->DataVersion = 0;
491 suffix->MemoryFlags = object::WIN_RES_PURE_MOVEABLE;
492 suffix->Language = SUBLANG_ENGLISH_US;
493 suffix->Version = 0;
494 suffix->Characteristics = 0;
495 buf += sizeof(object::WinResHeaderSuffix);
496 }
497
498 // Create a resource file containing a manifest XML.
createManifestRes()499 std::unique_ptr<MemoryBuffer> createManifestRes() {
500 std::string manifest = createManifestXml();
501
502 std::unique_ptr<WritableMemoryBuffer> res =
503 createMemoryBufferForManifestRes(manifest.size());
504
505 char *buf = res->getBufferStart();
506 writeResFileHeader(buf);
507 writeResEntryHeader(buf, manifest.size());
508
509 // Copy the manifest data into the .res file.
510 std::copy(manifest.begin(), manifest.end(), buf);
511 return std::move(res);
512 }
513
createSideBySideManifest()514 void createSideBySideManifest() {
515 std::string path = std::string(config->manifestFile);
516 if (path == "")
517 path = config->outputFile + ".manifest";
518 std::error_code ec;
519 raw_fd_ostream out(path, ec, sys::fs::OF_Text);
520 if (ec)
521 fatal("failed to create manifest: " + ec.message());
522 out << createManifestXml();
523 }
524
525 // Parse a string in the form of
526 // "<name>[=<internalname>][,@ordinal[,NONAME]][,DATA][,PRIVATE]"
527 // or "<name>=<dllname>.<name>".
528 // Used for parsing /export arguments.
parseExport(StringRef arg)529 Export parseExport(StringRef arg) {
530 Export e;
531 StringRef rest;
532 std::tie(e.name, rest) = arg.split(",");
533 if (e.name.empty())
534 goto err;
535
536 if (e.name.contains('=')) {
537 StringRef x, y;
538 std::tie(x, y) = e.name.split("=");
539
540 // If "<name>=<dllname>.<name>".
541 if (y.contains(".")) {
542 e.name = x;
543 e.forwardTo = y;
544 return e;
545 }
546
547 e.extName = x;
548 e.name = y;
549 if (e.name.empty())
550 goto err;
551 }
552
553 // If "<name>=<internalname>[,@ordinal[,NONAME]][,DATA][,PRIVATE]"
554 while (!rest.empty()) {
555 StringRef tok;
556 std::tie(tok, rest) = rest.split(",");
557 if (tok.equals_lower("noname")) {
558 if (e.ordinal == 0)
559 goto err;
560 e.noname = true;
561 continue;
562 }
563 if (tok.equals_lower("data")) {
564 e.data = true;
565 continue;
566 }
567 if (tok.equals_lower("constant")) {
568 e.constant = true;
569 continue;
570 }
571 if (tok.equals_lower("private")) {
572 e.isPrivate = true;
573 continue;
574 }
575 if (tok.startswith("@")) {
576 int32_t ord;
577 if (tok.substr(1).getAsInteger(0, ord))
578 goto err;
579 if (ord <= 0 || 65535 < ord)
580 goto err;
581 e.ordinal = ord;
582 continue;
583 }
584 goto err;
585 }
586 return e;
587
588 err:
589 fatal("invalid /export: " + arg);
590 }
591
undecorate(StringRef sym)592 static StringRef undecorate(StringRef sym) {
593 if (config->machine != I386)
594 return sym;
595 // In MSVC mode, a fully decorated stdcall function is exported
596 // as-is with the leading underscore (with type IMPORT_NAME).
597 // In MinGW mode, a decorated stdcall function gets the underscore
598 // removed, just like normal cdecl functions.
599 if (sym.startswith("_") && sym.contains('@') && !config->mingw)
600 return sym;
601 return sym.startswith("_") ? sym.substr(1) : sym;
602 }
603
604 // Convert stdcall/fastcall style symbols into unsuffixed symbols,
605 // with or without a leading underscore. (MinGW specific.)
killAt(StringRef sym,bool prefix)606 static StringRef killAt(StringRef sym, bool prefix) {
607 if (sym.empty())
608 return sym;
609 // Strip any trailing stdcall suffix
610 sym = sym.substr(0, sym.find('@', 1));
611 if (!sym.startswith("@")) {
612 if (prefix && !sym.startswith("_"))
613 return saver.save("_" + sym);
614 return sym;
615 }
616 // For fastcall, remove the leading @ and replace it with an
617 // underscore, if prefixes are used.
618 sym = sym.substr(1);
619 if (prefix)
620 sym = saver.save("_" + sym);
621 return sym;
622 }
623
624 // Performs error checking on all /export arguments.
625 // It also sets ordinals.
fixupExports()626 void fixupExports() {
627 // Symbol ordinals must be unique.
628 std::set<uint16_t> ords;
629 for (Export &e : config->exports) {
630 if (e.ordinal == 0)
631 continue;
632 if (!ords.insert(e.ordinal).second)
633 fatal("duplicate export ordinal: " + e.name);
634 }
635
636 for (Export &e : config->exports) {
637 if (!e.forwardTo.empty()) {
638 e.exportName = undecorate(e.name);
639 } else {
640 e.exportName = undecorate(e.extName.empty() ? e.name : e.extName);
641 }
642 }
643
644 if (config->killAt && config->machine == I386) {
645 for (Export &e : config->exports) {
646 e.name = killAt(e.name, true);
647 e.exportName = killAt(e.exportName, false);
648 e.extName = killAt(e.extName, true);
649 e.symbolName = killAt(e.symbolName, true);
650 }
651 }
652
653 // Uniquefy by name.
654 DenseMap<StringRef, Export *> map(config->exports.size());
655 std::vector<Export> v;
656 for (Export &e : config->exports) {
657 auto pair = map.insert(std::make_pair(e.exportName, &e));
658 bool inserted = pair.second;
659 if (inserted) {
660 v.push_back(e);
661 continue;
662 }
663 Export *existing = pair.first->second;
664 if (e == *existing || e.name != existing->name)
665 continue;
666 warn("duplicate /export option: " + e.name);
667 }
668 config->exports = std::move(v);
669
670 // Sort by name.
671 std::sort(config->exports.begin(), config->exports.end(),
672 [](const Export &a, const Export &b) {
673 return a.exportName < b.exportName;
674 });
675 }
676
assignExportOrdinals()677 void assignExportOrdinals() {
678 // Assign unique ordinals if default (= 0).
679 uint32_t max = 0;
680 for (Export &e : config->exports)
681 max = std::max(max, (uint32_t)e.ordinal);
682 for (Export &e : config->exports)
683 if (e.ordinal == 0)
684 e.ordinal = ++max;
685 if (max > std::numeric_limits<uint16_t>::max())
686 fatal("too many exported symbols (max " +
687 Twine(std::numeric_limits<uint16_t>::max()) + ")");
688 }
689
690 // Parses a string in the form of "key=value" and check
691 // if value matches previous values for the same key.
checkFailIfMismatch(StringRef arg,InputFile * source)692 void checkFailIfMismatch(StringRef arg, InputFile *source) {
693 StringRef k, v;
694 std::tie(k, v) = arg.split('=');
695 if (k.empty() || v.empty())
696 fatal("/failifmismatch: invalid argument: " + arg);
697 std::pair<StringRef, InputFile *> existing = config->mustMatch[k];
698 if (!existing.first.empty() && v != existing.first) {
699 std::string sourceStr = source ? toString(source) : "cmd-line";
700 std::string existingStr =
701 existing.second ? toString(existing.second) : "cmd-line";
702 fatal("/failifmismatch: mismatch detected for '" + k + "':\n>>> " +
703 existingStr + " has value " + existing.first + "\n>>> " + sourceStr +
704 " has value " + v);
705 }
706 config->mustMatch[k] = {v, source};
707 }
708
709 // Convert Windows resource files (.res files) to a .obj file.
710 // Does what cvtres.exe does, but in-process and cross-platform.
convertResToCOFF(ArrayRef<MemoryBufferRef> mbs,ArrayRef<ObjFile * > objs)711 MemoryBufferRef convertResToCOFF(ArrayRef<MemoryBufferRef> mbs,
712 ArrayRef<ObjFile *> objs) {
713 object::WindowsResourceParser parser(/* MinGW */ config->mingw);
714
715 std::vector<std::string> duplicates;
716 for (MemoryBufferRef mb : mbs) {
717 std::unique_ptr<object::Binary> bin = check(object::createBinary(mb));
718 object::WindowsResource *rf = dyn_cast<object::WindowsResource>(bin.get());
719 if (!rf)
720 fatal("cannot compile non-resource file as resource");
721
722 if (auto ec = parser.parse(rf, duplicates))
723 fatal(toString(std::move(ec)));
724 }
725
726 // Note: This processes all .res files before all objs. Ideally they'd be
727 // handled in the same order they were linked (to keep the right one, if
728 // there are duplicates that are tolerated due to forceMultipleRes).
729 for (ObjFile *f : objs) {
730 object::ResourceSectionRef rsf;
731 if (auto ec = rsf.load(f->getCOFFObj()))
732 fatal(toString(f) + ": " + toString(std::move(ec)));
733
734 if (auto ec = parser.parse(rsf, f->getName(), duplicates))
735 fatal(toString(std::move(ec)));
736 }
737
738 if (config->mingw)
739 parser.cleanUpManifests(duplicates);
740
741 for (const auto &dupeDiag : duplicates)
742 if (config->forceMultipleRes)
743 warn(dupeDiag);
744 else
745 error(dupeDiag);
746
747 Expected<std::unique_ptr<MemoryBuffer>> e =
748 llvm::object::writeWindowsResourceCOFF(config->machine, parser,
749 config->timestamp);
750 if (!e)
751 fatal("failed to write .res to COFF: " + toString(e.takeError()));
752
753 MemoryBufferRef mbref = **e;
754 make<std::unique_ptr<MemoryBuffer>>(std::move(*e)); // take ownership
755 return mbref;
756 }
757
758 // Create OptTable
759
760 // Create prefix string literals used in Options.td
761 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
762 #include "Options.inc"
763 #undef PREFIX
764
765 // Create table mapping all options defined in Options.td
766 static const llvm::opt::OptTable::Info infoTable[] = {
767 #define OPTION(X1, X2, ID, KIND, GROUP, ALIAS, X7, X8, X9, X10, X11, X12) \
768 {X1, X2, X10, X11, OPT_##ID, llvm::opt::Option::KIND##Class, \
769 X9, X8, OPT_##GROUP, OPT_##ALIAS, X7, X12},
770 #include "Options.inc"
771 #undef OPTION
772 };
773
COFFOptTable()774 COFFOptTable::COFFOptTable() : OptTable(infoTable, true) {}
775
776 COFFOptTable optTable;
777
778 // Set color diagnostics according to --color-diagnostics={auto,always,never}
779 // or --no-color-diagnostics flags.
handleColorDiagnostics(opt::InputArgList & args)780 static void handleColorDiagnostics(opt::InputArgList &args) {
781 auto *arg = args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
782 OPT_no_color_diagnostics);
783 if (!arg)
784 return;
785 if (arg->getOption().getID() == OPT_color_diagnostics) {
786 lld::errs().enable_colors(true);
787 } else if (arg->getOption().getID() == OPT_no_color_diagnostics) {
788 lld::errs().enable_colors(false);
789 } else {
790 StringRef s = arg->getValue();
791 if (s == "always")
792 lld::errs().enable_colors(true);
793 else if (s == "never")
794 lld::errs().enable_colors(false);
795 else if (s != "auto")
796 error("unknown option: --color-diagnostics=" + s);
797 }
798 }
799
getQuotingStyle(opt::InputArgList & args)800 static cl::TokenizerCallback getQuotingStyle(opt::InputArgList &args) {
801 if (auto *arg = args.getLastArg(OPT_rsp_quoting)) {
802 StringRef s = arg->getValue();
803 if (s != "windows" && s != "posix")
804 error("invalid response file quoting: " + s);
805 if (s == "windows")
806 return cl::TokenizeWindowsCommandLine;
807 return cl::TokenizeGNUCommandLine;
808 }
809 // The COFF linker always defaults to Windows quoting.
810 return cl::TokenizeWindowsCommandLine;
811 }
812
813 // Parses a given list of options.
parse(ArrayRef<const char * > argv)814 opt::InputArgList ArgParser::parse(ArrayRef<const char *> argv) {
815 // Make InputArgList from string vectors.
816 unsigned missingIndex;
817 unsigned missingCount;
818
819 // We need to get the quoting style for response files before parsing all
820 // options so we parse here before and ignore all the options but
821 // --rsp-quoting and /lldignoreenv.
822 // (This means --rsp-quoting can't be added through %LINK%.)
823 opt::InputArgList args = optTable.ParseArgs(argv, missingIndex, missingCount);
824
825 // Expand response files (arguments in the form of @<filename>) and insert
826 // flags from %LINK% and %_LINK_%, and then parse the argument again.
827 SmallVector<const char *, 256> expandedArgv(argv.data(),
828 argv.data() + argv.size());
829 if (!args.hasArg(OPT_lldignoreenv))
830 addLINK(expandedArgv);
831 cl::ExpandResponseFiles(saver, getQuotingStyle(args), expandedArgv);
832 args = optTable.ParseArgs(makeArrayRef(expandedArgv).drop_front(),
833 missingIndex, missingCount);
834
835 // Print the real command line if response files are expanded.
836 if (args.hasArg(OPT_verbose) && argv.size() != expandedArgv.size()) {
837 std::string msg = "Command line:";
838 for (const char *s : expandedArgv)
839 msg += " " + std::string(s);
840 message(msg);
841 }
842
843 // Save the command line after response file expansion so we can write it to
844 // the PDB if necessary.
845 config->argv = {expandedArgv.begin(), expandedArgv.end()};
846
847 // Handle /WX early since it converts missing argument warnings to errors.
848 errorHandler().fatalWarnings = args.hasFlag(OPT_WX, OPT_WX_no, false);
849
850 if (missingCount)
851 fatal(Twine(args.getArgString(missingIndex)) + ": missing argument");
852
853 handleColorDiagnostics(args);
854
855 for (opt::Arg *arg : args.filtered(OPT_UNKNOWN)) {
856 std::string nearest;
857 if (optTable.findNearest(arg->getAsString(args), nearest) > 1)
858 warn("ignoring unknown argument '" + arg->getAsString(args) + "'");
859 else
860 warn("ignoring unknown argument '" + arg->getAsString(args) +
861 "', did you mean '" + nearest + "'");
862 }
863
864 if (args.hasArg(OPT_lib))
865 warn("ignoring /lib since it's not the first argument");
866
867 return args;
868 }
869
870 // Tokenizes and parses a given string as command line in .drective section.
parseDirectives(StringRef s)871 ParsedDirectives ArgParser::parseDirectives(StringRef s) {
872 ParsedDirectives result;
873 SmallVector<const char *, 16> rest;
874
875 // Handle /EXPORT and /INCLUDE in a fast path. These directives can appear for
876 // potentially every symbol in the object, so they must be handled quickly.
877 SmallVector<StringRef, 16> tokens;
878 cl::TokenizeWindowsCommandLineNoCopy(s, saver, tokens);
879 for (StringRef tok : tokens) {
880 if (tok.startswith_lower("/export:") || tok.startswith_lower("-export:"))
881 result.exports.push_back(tok.substr(strlen("/export:")));
882 else if (tok.startswith_lower("/include:") ||
883 tok.startswith_lower("-include:"))
884 result.includes.push_back(tok.substr(strlen("/include:")));
885 else {
886 // Save non-null-terminated strings to make proper C strings.
887 bool HasNul = tok.data()[tok.size()] == '\0';
888 rest.push_back(HasNul ? tok.data() : saver.save(tok).data());
889 }
890 }
891
892 // Make InputArgList from unparsed string vectors.
893 unsigned missingIndex;
894 unsigned missingCount;
895
896 result.args = optTable.ParseArgs(rest, missingIndex, missingCount);
897
898 if (missingCount)
899 fatal(Twine(result.args.getArgString(missingIndex)) + ": missing argument");
900 for (auto *arg : result.args.filtered(OPT_UNKNOWN))
901 warn("ignoring unknown argument: " + arg->getAsString(result.args));
902 return result;
903 }
904
905 // link.exe has an interesting feature. If LINK or _LINK_ environment
906 // variables exist, their contents are handled as command line strings.
907 // So you can pass extra arguments using them.
addLINK(SmallVector<const char *,256> & argv)908 void ArgParser::addLINK(SmallVector<const char *, 256> &argv) {
909 // Concatenate LINK env and command line arguments, and then parse them.
910 if (Optional<std::string> s = Process::GetEnv("LINK")) {
911 std::vector<const char *> v = tokenize(*s);
912 argv.insert(std::next(argv.begin()), v.begin(), v.end());
913 }
914 if (Optional<std::string> s = Process::GetEnv("_LINK_")) {
915 std::vector<const char *> v = tokenize(*s);
916 argv.insert(std::next(argv.begin()), v.begin(), v.end());
917 }
918 }
919
tokenize(StringRef s)920 std::vector<const char *> ArgParser::tokenize(StringRef s) {
921 SmallVector<const char *, 16> tokens;
922 cl::TokenizeWindowsCommandLine(s, saver, tokens);
923 return std::vector<const char *>(tokens.begin(), tokens.end());
924 }
925
printHelp(const char * argv0)926 void printHelp(const char *argv0) {
927 optTable.PrintHelp(lld::outs(),
928 (std::string(argv0) + " [options] file...").c_str(),
929 "LLVM Linker", false);
930 }
931
932 } // namespace coff
933 } // namespace lld
934