Bug Summary

File:include/llvm/Support/Error.h
Warning:line 201, column 5
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name llvm-ar.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/llvm-ar -I /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/llvm-ar -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp

→
1//===-- llvm-ar.cpp - LLVM archive librarian utility ----------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// Builds up (relatively) standard unix archive files (.a) containing LLVM
11// bitcode or other files.
12//
13//===----------------------------------------------------------------------===//
14
15#include "llvm/ADT/StringSwitch.h"
16#include "llvm/ADT/Triple.h"
17#include "llvm/IR/LLVMContext.h"
18#include "llvm/Object/Archive.h"
19#include "llvm/Object/ArchiveWriter.h"
20#include "llvm/Object/MachO.h"
21#include "llvm/Object/ObjectFile.h"
22#include "llvm/Support/Chrono.h"
23#include "llvm/Support/CommandLine.h"
24#include "llvm/Support/Errc.h"
25#include "llvm/Support/FileSystem.h"
26#include "llvm/Support/Format.h"
27#include "llvm/Support/FormatVariadic.h"
28#include "llvm/Support/InitLLVM.h"
29#include "llvm/Support/LineIterator.h"
30#include "llvm/Support/MemoryBuffer.h"
31#include "llvm/Support/Path.h"
32#include "llvm/Support/Process.h"
33#include "llvm/Support/StringSaver.h"
34#include "llvm/Support/TargetSelect.h"
35#include "llvm/Support/ToolOutputFile.h"
36#include "llvm/Support/raw_ostream.h"
37#include "llvm/ToolDrivers/llvm-dlltool/DlltoolDriver.h"
38#include "llvm/ToolDrivers/llvm-lib/LibDriver.h"
39
40#if !defined(_MSC_VER) && !defined(__MINGW32__)
41#include <unistd.h>
42#else
43#include <io.h>
44#endif
45
46using namespace llvm;
47
48// The name this program was invoked as.
49static StringRef ToolName;
50
51// The basename of this program.
52static StringRef Stem;
53
54const char RanlibHelp[] = R"(
55OVERVIEW: LLVM Ranlib (llvm-ranlib)
56
57 This program generates an index to speed access to archives
58
59USAGE: llvm-ranlib <archive-file>
60
61OPTIONS:
62 -help - Display available options
63 -version - Display the version of this program
64)";
65
66const char ArHelp[] = R"(
67OVERVIEW: LLVM Archiver
68
69USAGE: llvm-ar [options] [-]<operation>[modifiers] [relpos] <archive> [files]
70 llvm-ar -M [<mri-script]
71
72OPTIONS:
73 --format - Archive format to create
74 =default - default
75 =gnu - gnu
76 =darwin - darwin
77 =bsd - bsd
78 --plugin=<string> - Ignored for compatibility
79 --help - Display available options
80 --version - Display the version of this program
81
82OPERATIONS:
83 d - delete [files] from the archive
84 m - move [files] in the archive
85 p - print [files] found in the archive
86 q - quick append [files] to the archive
87 r - replace or insert [files] into the archive
88 s - act as ranlib
89 t - display contents of archive
90 x - extract [files] from the archive
91
92MODIFIERS:
93 [a] - put [files] after [relpos]
94 [b] - put [files] before [relpos] (same as [i])
95 [c] - do not warn if archive had to be created
96 [D] - use zero for timestamps and uids/gids (default)
97 [i] - put [files] before [relpos] (same as [b])
98 [l] - ignored for compatibility
99 [L] - add archive's contents
100 [o] - preserve original dates
101 [s] - create an archive index (cf. ranlib)
102 [S] - do not build a symbol table
103 [T] - create a thin archive
104 [u] - update only [files] newer than archive contents
105 [U] - use actual timestamps and uids/gids
106 [v] - be verbose about actions taken
107)";
108
109void printHelpMessage() {
110 if (Stem.contains_lower("ranlib"))
111 outs() << RanlibHelp;
112 else if (Stem.contains_lower("ar"))
113 outs() << ArHelp;
114}
115
116// Show the error message and exit.
117LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) static void fail(Twine Error) {
118 errs() << ToolName << ": " << Error << ".\n";
119 printHelpMessage();
120 exit(1);
121}
122
123static void failIfError(std::error_code EC, Twine Context = "") {
124 if (!EC)
125 return;
126
127 std::string ContextStr = Context.str();
128 if (ContextStr == "")
129 fail(EC.message());
130 fail(Context + ": " + EC.message());
131}
132
133static void failIfError(Error E, Twine Context = "") {
134 if (!E)
7
←
Taking false branch
→
135 return;
136
137 handleAllErrors(std::move(E), [&](const llvm::ErrorInfoBase &EIB) {
8
←
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp:137:33)>'
→
138 std::string ContextStr = Context.str();
139 if (ContextStr == "")
140 fail(EIB.message());
141 fail(Context + ": " + EIB.message());
142 });
143}
144
145static SmallVector<const char *, 256> PositionalArgs;
146
147static bool MRI;
148
149namespace {
150enum Format { Default, GNU, BSD, DARWIN, Unknown };
151}
152
153static Format FormatType = Default;
154
155static std::string Options;
156
157// This enumeration delineates the kinds of operations on an archive
158// that are permitted.
159enum ArchiveOperation {
160 Print, ///< Print the contents of the archive
161 Delete, ///< Delete the specified members
162 Move, ///< Move members to end or as given by {a,b,i} modifiers
163 QuickAppend, ///< Quickly append to end of archive
164 ReplaceOrInsert, ///< Replace or Insert members
165 DisplayTable, ///< Display the table of contents
166 Extract, ///< Extract files back to file system
167 CreateSymTab ///< Create a symbol table in an existing archive
168};
169
170// Modifiers to follow operation to vary behavior
171static bool AddAfter = false; ///< 'a' modifier
172static bool AddBefore = false; ///< 'b' modifier
173static bool Create = false; ///< 'c' modifier
174static bool OriginalDates = false; ///< 'o' modifier
175static bool OnlyUpdate = false; ///< 'u' modifier
176static bool Verbose = false; ///< 'v' modifier
177static bool Symtab = true; ///< 's' modifier
178static bool Deterministic = true; ///< 'D' and 'U' modifiers
179static bool Thin = false; ///< 'T' modifier
180static bool AddLibrary = false; ///< 'L' modifier
181
182// Relative Positional Argument (for insert/move). This variable holds
183// the name of the archive member to which the 'a', 'b' or 'i' modifier
184// refers. Only one of 'a', 'b' or 'i' can be specified so we only need
185// one variable.
186static std::string RelPos;
187
188// This variable holds the name of the archive file as given on the
189// command line.
190static std::string ArchiveName;
191
192// This variable holds the list of member files to proecess, as given
193// on the command line.
194static std::vector<StringRef> Members;
195
196// Extract the member filename from the command line for the [relpos] argument
197// associated with a, b, and i modifiers
198static void getRelPos() {
199 if (PositionalArgs.size() == 0)
200 fail("Expected [relpos] for a, b, or i modifier");
201 RelPos = PositionalArgs[0];
202 PositionalArgs.erase(PositionalArgs.begin());
203}
204
205// Get the archive file name from the command line
206static void getArchive() {
207 if (PositionalArgs.size() == 0)
208 fail("An archive name must be specified");
209 ArchiveName = PositionalArgs[0];
210 PositionalArgs.erase(PositionalArgs.begin());
211}
212
213// Copy over remaining items in PositionalArgs to our Members vector
214static void getMembers() {
215 for (auto &Arg : PositionalArgs)
216 Members.push_back(Arg);
217}
218
219std::vector<std::unique_ptr<MemoryBuffer>> ArchiveBuffers;
220std::vector<std::unique_ptr<object::Archive>> Archives;
221
222static object::Archive &readLibrary(const Twine &Library) {
223 auto BufOrErr = MemoryBuffer::getFile(Library, -1, false);
224 failIfError(BufOrErr.getError(), "Could not open library");
225 ArchiveBuffers.push_back(std::move(*BufOrErr));
226 auto LibOrErr =
227 object::Archive::create(ArchiveBuffers.back()->getMemBufferRef());
228 failIfError(errorToErrorCode(LibOrErr.takeError()),
229 "Could not parse library");
230 Archives.push_back(std::move(*LibOrErr));
231 return *Archives.back();
232}
233
234static void runMRIScript();
235
236// Parse the command line options as presented and return the operation
237// specified. Process all modifiers and check to make sure that constraints on
238// modifier/operation pairs have not been violated.
239static ArchiveOperation parseCommandLine() {
240 if (MRI) {
241 if (!PositionalArgs.empty() || !Options.empty())
242 fail("Cannot mix -M and other options");
243 runMRIScript();
244 }
245
246 // Keep track of number of operations. We can only specify one
247 // per execution.
248 unsigned NumOperations = 0;
249
250 // Keep track of the number of positional modifiers (a,b,i). Only
251 // one can be specified.
252 unsigned NumPositional = 0;
253
254 // Keep track of which operation was requested
255 ArchiveOperation Operation;
256
257 bool MaybeJustCreateSymTab = false;
258
259 for (unsigned i = 0; i < Options.size(); ++i) {
260 switch (Options[i]) {
261 case 'd':
262 ++NumOperations;
263 Operation = Delete;
264 break;
265 case 'm':
266 ++NumOperations;
267 Operation = Move;
268 break;
269 case 'p':
270 ++NumOperations;
271 Operation = Print;
272 break;
273 case 'q':
274 ++NumOperations;
275 Operation = QuickAppend;
276 break;
277 case 'r':
278 ++NumOperations;
279 Operation = ReplaceOrInsert;
280 break;
281 case 't':
282 ++NumOperations;
283 Operation = DisplayTable;
284 break;
285 case 'x':
286 ++NumOperations;
287 Operation = Extract;
288 break;
289 case 'c':
290 Create = true;
291 break;
292 case 'l': /* accepted but unused */
293 break;
294 case 'o':
295 OriginalDates = true;
296 break;
297 case 's':
298 Symtab = true;
299 MaybeJustCreateSymTab = true;
300 break;
301 case 'S':
302 Symtab = false;
303 break;
304 case 'u':
305 OnlyUpdate = true;
306 break;
307 case 'v':
308 Verbose = true;
309 break;
310 case 'a':
311 getRelPos();
312 AddAfter = true;
313 NumPositional++;
314 break;
315 case 'b':
316 getRelPos();
317 AddBefore = true;
318 NumPositional++;
319 break;
320 case 'i':
321 getRelPos();
322 AddBefore = true;
323 NumPositional++;
324 break;
325 case 'D':
326 Deterministic = true;
327 break;
328 case 'U':
329 Deterministic = false;
330 break;
331 case 'T':
332 Thin = true;
333 break;
334 case 'L':
335 AddLibrary = true;
336 break;
337 default:
338 fail(std::string("unknown option ") + Options[i]);
339 }
340 }
341
342 // At this point, the next thing on the command line must be
343 // the archive name.
344 getArchive();
345
346 // Everything on the command line at this point is a member.
347 getMembers();
348
349 if (NumOperations == 0 && MaybeJustCreateSymTab) {
350 NumOperations = 1;
351 Operation = CreateSymTab;
352 if (!Members.empty())
353 fail("The s operation takes only an archive as argument");
354 }
355
356 // Perform various checks on the operation/modifier specification
357 // to make sure we are dealing with a legal request.
358 if (NumOperations == 0)
359 fail("You must specify at least one of the operations");
360 if (NumOperations > 1)
361 fail("Only one operation may be specified");
362 if (NumPositional > 1)
363 fail("You may only specify one of a, b, and i modifiers");
364 if (AddAfter || AddBefore) {
365 if (Operation != Move && Operation != ReplaceOrInsert)
366 fail("The 'a', 'b' and 'i' modifiers can only be specified with "
367 "the 'm' or 'r' operations");
368 }
369 if (OriginalDates && Operation != Extract)
370 fail("The 'o' modifier is only applicable to the 'x' operation");
371 if (OnlyUpdate && Operation != ReplaceOrInsert)
372 fail("The 'u' modifier is only applicable to the 'r' operation");
373 if (AddLibrary && Operation != QuickAppend)
374 fail("The 'L' modifier is only applicable to the 'q' operation");
375
376 // Return the parsed operation to the caller
377 return Operation;
378}
379
380// Implements the 'p' operation. This function traverses the archive
381// looking for members that match the path list.
382static void doPrint(StringRef Name, const object::Archive::Child &C) {
383 if (Verbose)
384 outs() << "Printing " << Name << "\n";
385
386 Expected<StringRef> DataOrErr = C.getBuffer();
387 failIfError(DataOrErr.takeError());
388 StringRef Data = *DataOrErr;
389 outs().write(Data.data(), Data.size());
390}
391
392// Utility function for printing out the file mode when the 't' operation is in
393// verbose mode.
394static void printMode(unsigned mode) {
395 outs() << ((mode & 004) ? "r" : "-");
396 outs() << ((mode & 002) ? "w" : "-");
397 outs() << ((mode & 001) ? "x" : "-");
398}
399
400// Implement the 't' operation. This function prints out just
401// the file names of each of the members. However, if verbose mode is requested
402// ('v' modifier) then the file type, permission mode, user, group, size, and
403// modification time are also printed.
404static void doDisplayTable(StringRef Name, const object::Archive::Child &C) {
405 if (Verbose) {
406 Expected<sys::fs::perms> ModeOrErr = C.getAccessMode();
407 failIfError(ModeOrErr.takeError());
408 sys::fs::perms Mode = ModeOrErr.get();
409 printMode((Mode >> 6) & 007);
410 printMode((Mode >> 3) & 007);
411 printMode(Mode & 007);
412 Expected<unsigned> UIDOrErr = C.getUID();
413 failIfError(UIDOrErr.takeError());
414 outs() << ' ' << UIDOrErr.get();
415 Expected<unsigned> GIDOrErr = C.getGID();
416 failIfError(GIDOrErr.takeError());
417 outs() << '/' << GIDOrErr.get();
418 Expected<uint64_t> Size = C.getSize();
419 failIfError(Size.takeError());
420 outs() << ' ' << format("%6llu", Size.get());
421 auto ModTimeOrErr = C.getLastModified();
422 failIfError(ModTimeOrErr.takeError());
423 // Note: formatv() only handles the default TimePoint<>, which is in
424 // nanoseconds.
425 // TODO: fix format_provider<TimePoint<>> to allow other units.
426 sys::TimePoint<> ModTimeInNs = ModTimeOrErr.get();
427 outs() << ' ' << formatv("{0:%b %e %H:%M %Y}", ModTimeInNs);
428 outs() << ' ';
429 }
430
431 if (C.getParent()->isThin()) {
432 outs() << sys::path::parent_path(ArchiveName);
433 outs() << '/';
434 }
435 outs() << Name << "\n";
436}
437
438// Implement the 'x' operation. This function extracts files back to the file
439// system.
440static void doExtract(StringRef Name, const object::Archive::Child &C) {
441 // Retain the original mode.
442 Expected<sys::fs::perms> ModeOrErr = C.getAccessMode();
443 failIfError(ModeOrErr.takeError());
444 sys::fs::perms Mode = ModeOrErr.get();
445
446 int FD;
447 failIfError(sys::fs::openFileForWrite(sys::path::filename(Name), FD,
448 sys::fs::CD_CreateAlways,
449 sys::fs::F_None, Mode),
450 Name);
451
452 {
453 raw_fd_ostream file(FD, false);
454
455 // Get the data and its length
456 Expected<StringRef> BufOrErr = C.getBuffer();
457 failIfError(BufOrErr.takeError());
458 StringRef Data = BufOrErr.get();
459
460 // Write the data.
461 file.write(Data.data(), Data.size());
462 }
463
464 // If we're supposed to retain the original modification times, etc. do so
465 // now.
466 if (OriginalDates) {
467 auto ModTimeOrErr = C.getLastModified();
468 failIfError(ModTimeOrErr.takeError());
469 failIfError(
470 sys::fs::setLastAccessAndModificationTime(FD, ModTimeOrErr.get()));
471 }
472
473 if (close(FD))
474 fail("Could not close the file");
475}
476
477static bool shouldCreateArchive(ArchiveOperation Op) {
478 switch (Op) {
479 case Print:
480 case Delete:
481 case Move:
482 case DisplayTable:
483 case Extract:
484 case CreateSymTab:
485 return false;
486
487 case QuickAppend:
488 case ReplaceOrInsert:
489 return true;
490 }
491
492 llvm_unreachable("Missing entry in covered switch.")::llvm::llvm_unreachable_internal("Missing entry in covered switch."
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 492);
493}
494
495static void performReadOperation(ArchiveOperation Operation,
496 object::Archive *OldArchive) {
497 if (Operation == Extract && OldArchive->isThin())
498 fail("extracting from a thin archive is not supported");
499
500 bool Filter = !Members.empty();
501 {
502 Error Err = Error::success();
503 for (auto &C : OldArchive->children(Err)) {
504 Expected<StringRef> NameOrErr = C.getName();
505 failIfError(NameOrErr.takeError());
506 StringRef Name = NameOrErr.get();
507
508 if (Filter) {
509 auto I = find(Members, Name);
510 if (I == Members.end())
511 continue;
512 Members.erase(I);
513 }
514
515 switch (Operation) {
516 default:
517 llvm_unreachable("Not a read operation")::llvm::llvm_unreachable_internal("Not a read operation", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 517);
518 case Print:
519 doPrint(Name, C);
520 break;
521 case DisplayTable:
522 doDisplayTable(Name, C);
523 break;
524 case Extract:
525 doExtract(Name, C);
526 break;
527 }
528 }
529 failIfError(std::move(Err));
530 }
531
532 if (Members.empty())
533 return;
534 for (StringRef Name : Members)
535 errs() << Name << " was not found\n";
536 exit(1);
537}
538
539static void addMember(std::vector<NewArchiveMember> &Members,
540 StringRef FileName, int Pos = -1) {
541 Expected<NewArchiveMember> NMOrErr =
542 NewArchiveMember::getFile(FileName, Deterministic);
543 failIfError(NMOrErr.takeError(), FileName);
544
545 // Use the basename of the object path for the member name.
546 NMOrErr->MemberName = sys::path::filename(NMOrErr->MemberName);
547
548 if (Pos == -1)
549 Members.push_back(std::move(*NMOrErr));
550 else
551 Members[Pos] = std::move(*NMOrErr);
552}
553
554static void addMember(std::vector<NewArchiveMember> &Members,
555 const object::Archive::Child &M, int Pos = -1) {
556 if (Thin && !M.getParent()->isThin())
557 fail("Cannot convert a regular archive to a thin one");
558 Expected<NewArchiveMember> NMOrErr =
559 NewArchiveMember::getOldMember(M, Deterministic);
560 failIfError(NMOrErr.takeError());
561 if (Pos == -1)
562 Members.push_back(std::move(*NMOrErr));
563 else
564 Members[Pos] = std::move(*NMOrErr);
565}
566
567static void addLibMember(std::vector<NewArchiveMember> &Members,
568 StringRef FileName) {
569 Expected<NewArchiveMember> NMOrErr =
570 NewArchiveMember::getFile(FileName, Deterministic);
571 failIfError(NMOrErr.takeError(), FileName);
572 if (identify_magic(NMOrErr->Buf->getBuffer()) == file_magic::archive) {
573 object::Archive &Lib = readLibrary(FileName);
574 Error Err = Error::success();
575
576 for (auto &Child : Lib.children(Err))
577 addMember(Members, Child);
578
579 failIfError(std::move(Err));
580 } else {
581 // Use the basename of the object path for the member name.
582 NMOrErr->MemberName = sys::path::filename(NMOrErr->MemberName);
583 Members.push_back(std::move(*NMOrErr));
584 }
585}
586
587enum InsertAction {
588 IA_AddOldMember,
589 IA_AddNewMember,
590 IA_Delete,
591 IA_MoveOldMember,
592 IA_MoveNewMember
593};
594
595static InsertAction computeInsertAction(ArchiveOperation Operation,
596 const object::Archive::Child &Member,
597 StringRef Name,
598 std::vector<StringRef>::iterator &Pos) {
599 if (Operation == QuickAppend || Members.empty())
600 return IA_AddOldMember;
601
602 auto MI = find_if(Members, [Name](StringRef Path) {
603 return Name == sys::path::filename(Path);
604 });
605
606 if (MI == Members.end())
607 return IA_AddOldMember;
608
609 Pos = MI;
610
611 if (Operation == Delete)
612 return IA_Delete;
613
614 if (Operation == Move)
615 return IA_MoveOldMember;
616
617 if (Operation == ReplaceOrInsert) {
618 StringRef PosName = sys::path::filename(RelPos);
619 if (!OnlyUpdate) {
620 if (PosName.empty())
621 return IA_AddNewMember;
622 return IA_MoveNewMember;
623 }
624
625 // We could try to optimize this to a fstat, but it is not a common
626 // operation.
627 sys::fs::file_status Status;
628 failIfError(sys::fs::status(*MI, Status), *MI);
629 auto ModTimeOrErr = Member.getLastModified();
630 failIfError(ModTimeOrErr.takeError());
631 if (Status.getLastModificationTime() < ModTimeOrErr.get()) {
632 if (PosName.empty())
633 return IA_AddOldMember;
634 return IA_MoveOldMember;
635 }
636
637 if (PosName.empty())
638 return IA_AddNewMember;
639 return IA_MoveNewMember;
640 }
641 llvm_unreachable("No such operation")::llvm::llvm_unreachable_internal("No such operation", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 641);
642}
643
644// We have to walk this twice and computing it is not trivial, so creating an
645// explicit std::vector is actually fairly efficient.
646static std::vector<NewArchiveMember>
647computeNewArchiveMembers(ArchiveOperation Operation,
648 object::Archive *OldArchive) {
649 std::vector<NewArchiveMember> Ret;
650 std::vector<NewArchiveMember> Moved;
651 int InsertPos = -1;
652 StringRef PosName = sys::path::filename(RelPos);
653 if (OldArchive) {
4
←
Assuming 'OldArchive' is non-null
→
5
←
Taking true branch
→
654 Error Err = Error::success();
655 for (auto &Child : OldArchive->children(Err)) {
656 int Pos = Ret.size();
657 Expected<StringRef> NameOrErr = Child.getName();
658 failIfError(NameOrErr.takeError());
659 StringRef Name = NameOrErr.get();
660 if (Name == PosName) {
661 assert(AddAfter || AddBefore)((AddAfter || AddBefore) ? static_cast<void> (0) : __assert_fail
("AddAfter || AddBefore", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 661, __PRETTY_FUNCTION__));
662 if (AddBefore)
663 InsertPos = Pos;
664 else
665 InsertPos = Pos + 1;
666 }
667
668 std::vector<StringRef>::iterator MemberI = Members.end();
669 InsertAction Action =
670 computeInsertAction(Operation, Child, Name, MemberI);
671 switch (Action) {
672 case IA_AddOldMember:
673 addMember(Ret, Child);
674 break;
675 case IA_AddNewMember:
676 addMember(Ret, *MemberI);
677 break;
678 case IA_Delete:
679 break;
680 case IA_MoveOldMember:
681 addMember(Moved, Child);
682 break;
683 case IA_MoveNewMember:
684 addMember(Moved, *MemberI);
685 break;
686 }
687 if (MemberI != Members.end())
688 Members.erase(MemberI);
689 }
690 failIfError(std::move(Err));
6
←
Calling 'failIfError'
→
691 }
692
693 if (Operation == Delete)
694 return Ret;
695
696 if (!RelPos.empty() && InsertPos == -1)
697 fail("Insertion point not found");
698
699 if (RelPos.empty())
700 InsertPos = Ret.size();
701
702 assert(unsigned(InsertPos) <= Ret.size())((unsigned(InsertPos) <= Ret.size()) ? static_cast<void
> (0) : __assert_fail ("unsigned(InsertPos) <= Ret.size()"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 702, __PRETTY_FUNCTION__));
703 int Pos = InsertPos;
704 for (auto &M : Moved) {
705 Ret.insert(Ret.begin() + Pos, std::move(M));
706 ++Pos;
707 }
708
709 if (AddLibrary) {
710 assert(Operation == QuickAppend)((Operation == QuickAppend) ? static_cast<void> (0) : __assert_fail
("Operation == QuickAppend", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 710, __PRETTY_FUNCTION__));
711 for (auto &Member : Members)
712 addLibMember(Ret, Member);
713 return Ret;
714 }
715
716 for (unsigned I = 0; I != Members.size(); ++I)
717 Ret.insert(Ret.begin() + InsertPos, NewArchiveMember());
718 Pos = InsertPos;
719 for (auto &Member : Members) {
720 addMember(Ret, Member, Pos);
721 ++Pos;
722 }
723
724 return Ret;
725}
726
727static object::Archive::Kind getDefaultForHost() {
728 return Triple(sys::getProcessTriple()).isOSDarwin()
729 ? object::Archive::K_DARWIN
730 : object::Archive::K_GNU;
731}
732
733static object::Archive::Kind getKindFromMember(const NewArchiveMember &Member) {
734 Expected<std::unique_ptr<object::ObjectFile>> OptionalObject =
735 object::ObjectFile::createObjectFile(Member.Buf->getMemBufferRef());
736
737 if (OptionalObject)
738 return isa<object::MachOObjectFile>(**OptionalObject)
739 ? object::Archive::K_DARWIN
740 : object::Archive::K_GNU;
741
742 // squelch the error in case we had a non-object file
743 consumeError(OptionalObject.takeError());
744 return getDefaultForHost();
745}
746
747static void performWriteOperation(ArchiveOperation Operation,
748 object::Archive *OldArchive,
749 std::unique_ptr<MemoryBuffer> OldArchiveBuf,
750 std::vector<NewArchiveMember> *NewMembersP) {
751 std::vector<NewArchiveMember> NewMembers;
752 if (!NewMembersP)
1
Assuming 'NewMembersP' is null
→
2
←
Taking true branch
→
753 NewMembers = computeNewArchiveMembers(Operation, OldArchive);
3
←
Calling 'computeNewArchiveMembers'
→
754
755 object::Archive::Kind Kind;
756 switch (FormatType) {
757 case Default:
758 if (Thin)
759 Kind = object::Archive::K_GNU;
760 else if (OldArchive)
761 Kind = OldArchive->kind();
762 else if (NewMembersP)
763 Kind = NewMembersP->size() ? getKindFromMember(NewMembersP->front())
764 : getDefaultForHost();
765 else
766 Kind = NewMembers.size() ? getKindFromMember(NewMembers.front())
767 : getDefaultForHost();
768 break;
769 case GNU:
770 Kind = object::Archive::K_GNU;
771 break;
772 case BSD:
773 if (Thin)
774 fail("Only the gnu format has a thin mode");
775 Kind = object::Archive::K_BSD;
776 break;
777 case DARWIN:
778 if (Thin)
779 fail("Only the gnu format has a thin mode");
780 Kind = object::Archive::K_DARWIN;
781 break;
782 case Unknown:
783 llvm_unreachable("")::llvm::llvm_unreachable_internal("", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 783);
784 }
785
786 Error E =
787 writeArchive(ArchiveName, NewMembersP ? *NewMembersP : NewMembers, Symtab,
788 Kind, Deterministic, Thin, std::move(OldArchiveBuf));
789 failIfError(std::move(E), ArchiveName);
790}
791
792static void createSymbolTable(object::Archive *OldArchive) {
793 // When an archive is created or modified, if the s option is given, the
794 // resulting archive will have a current symbol table. If the S option
795 // is given, it will have no symbol table.
796 // In summary, we only need to update the symbol table if we have none.
797 // This is actually very common because of broken build systems that think
798 // they have to run ranlib.
799 if (OldArchive->hasSymbolTable())
800 return;
801
802 performWriteOperation(CreateSymTab, OldArchive, nullptr, nullptr);
803}
804
805static void performOperation(ArchiveOperation Operation,
806 object::Archive *OldArchive,
807 std::unique_ptr<MemoryBuffer> OldArchiveBuf,
808 std::vector<NewArchiveMember> *NewMembers) {
809 switch (Operation) {
810 case Print:
811 case DisplayTable:
812 case Extract:
813 performReadOperation(Operation, OldArchive);
814 return;
815
816 case Delete:
817 case Move:
818 case QuickAppend:
819 case ReplaceOrInsert:
820 performWriteOperation(Operation, OldArchive, std::move(OldArchiveBuf),
821 NewMembers);
822 return;
823 case CreateSymTab:
824 createSymbolTable(OldArchive);
825 return;
826 }
827 llvm_unreachable("Unknown operation.")::llvm::llvm_unreachable_internal("Unknown operation.", "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 827);
828}
829
830static int performOperation(ArchiveOperation Operation,
831 std::vector<NewArchiveMember> *NewMembers) {
832 // Create or open the archive object.
833 ErrorOr<std::unique_ptr<MemoryBuffer>> Buf =
834 MemoryBuffer::getFile(ArchiveName, -1, false);
835 std::error_code EC = Buf.getError();
836 if (EC && EC != errc::no_such_file_or_directory)
837 fail("error opening '" + ArchiveName + "': " + EC.message() + "!");
838
839 if (!EC) {
840 Error Err = Error::success();
841 object::Archive Archive(Buf.get()->getMemBufferRef(), Err);
842 EC = errorToErrorCode(std::move(Err));
843 failIfError(EC,
844 "error loading '" + ArchiveName + "': " + EC.message() + "!");
845 performOperation(Operation, &Archive, std::move(Buf.get()), NewMembers);
846 return 0;
847 }
848
849 assert(EC == errc::no_such_file_or_directory)((EC == errc::no_such_file_or_directory) ? static_cast<void
> (0) : __assert_fail ("EC == errc::no_such_file_or_directory"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp"
, 849, __PRETTY_FUNCTION__));
850
851 if (!shouldCreateArchive(Operation)) {
852 failIfError(EC, Twine("error loading '") + ArchiveName + "'");
853 } else {
854 if (!Create) {
855 // Produce a warning if we should and we're creating the archive
856 errs() << ToolName << ": creating " << ArchiveName << "\n";
857 }
858 }
859
860 performOperation(Operation, nullptr, nullptr, NewMembers);
861 return 0;
862}
863
864static void runMRIScript() {
865 enum class MRICommand { AddLib, AddMod, Create, Delete, Save, End, Invalid };
866
867 ErrorOr<std::unique_ptr<MemoryBuffer>> Buf = MemoryBuffer::getSTDIN();
868 failIfError(Buf.getError());
869 const MemoryBuffer &Ref = *Buf.get();
870 bool Saved = false;
871 std::vector<NewArchiveMember> NewMembers;
872
873 for (line_iterator I(Ref, /*SkipBlanks*/ false), E; I != E; ++I) {
874 StringRef Line = *I;
875 Line = Line.split(';').first;
876 Line = Line.split('*').first;
877 Line = Line.trim();
878 if (Line.empty())
879 continue;
880 StringRef CommandStr, Rest;
881 std::tie(CommandStr, Rest) = Line.split(' ');
882 Rest = Rest.trim();
883 if (!Rest.empty() && Rest.front() == '"' && Rest.back() == '"')
884 Rest = Rest.drop_front().drop_back();
885 auto Command = StringSwitch<MRICommand>(CommandStr.lower())
886 .Case("addlib", MRICommand::AddLib)
887 .Case("addmod", MRICommand::AddMod)
888 .Case("create", MRICommand::Create)
889 .Case("delete", MRICommand::Delete)
890 .Case("save", MRICommand::Save)
891 .Case("end", MRICommand::End)
892 .Default(MRICommand::Invalid);
893
894 switch (Command) {
895 case MRICommand::AddLib: {
896 object::Archive &Lib = readLibrary(Rest);
897 {
898 Error Err = Error::success();
899 for (auto &Member : Lib.children(Err))
900 addMember(NewMembers, Member);
901 failIfError(std::move(Err));
902 }
903 break;
904 }
905 case MRICommand::AddMod:
906 addMember(NewMembers, Rest);
907 break;
908 case MRICommand::Create:
909 Create = true;
910 if (!ArchiveName.empty())
911 fail("Editing multiple archives not supported");
912 if (Saved)
913 fail("File already saved");
914 ArchiveName = Rest;
915 break;
916 case MRICommand::Delete: {
917 StringRef Name = sys::path::filename(Rest);
918 llvm::erase_if(NewMembers,
919 [=](NewArchiveMember &M) { return M.MemberName == Name; });
920 break;
921 }
922 case MRICommand::Save:
923 Saved = true;
924 break;
925 case MRICommand::End:
926 break;
927 case MRICommand::Invalid:
928 fail("Unknown command: " + CommandStr);
929 }
930 }
931
932 // Nothing to do if not saved.
933 if (Saved)
934 performOperation(ReplaceOrInsert, &NewMembers);
935 exit(0);
936}
937
938static bool handleGenericOption(StringRef arg) {
939 if (arg == "-help" || arg == "--help") {
940 printHelpMessage();
941 return true;
942 }
943 if (arg == "-version" || arg == "--version") {
944 cl::PrintVersionMessage();
945 return true;
946 }
947 return false;
948}
949
950static int ar_main(int argc, char **argv) {
951 SmallVector<const char *, 0> Argv(argv, argv + argc);
952 BumpPtrAllocator Alloc;
953 StringSaver Saver(Alloc);
954 cl::ExpandResponseFiles(Saver, cl::TokenizeGNUCommandLine, Argv);
955 for (size_t i = 1; i < Argv.size(); ++i) {
956 StringRef Arg = Argv[i];
957 const char *match;
958 auto MatchFlagWithArg = [&](const char *expected) {
959 size_t len = strlen(expected);
960 if (Arg == expected) {
961 if (++i >= Argv.size())
962 fail(std::string(expected) + " requires an argument");
963 match = Argv[i];
964 return true;
965 }
966 if (Arg.startswith(expected) && Arg.size() > len && Arg[len] == '=') {
967 match = Arg.data() + len + 1;
968 return true;
969 }
970 return false;
971 };
972 if (handleGenericOption(Argv[i]))
973 return 0;
974 if (Arg == "--") {
975 for (; i < Argv.size(); ++i)
976 PositionalArgs.push_back(Argv[i]);
977 break;
978 }
979 if (Arg[0] == '-') {
980 if (Arg.startswith("--"))
981 Arg = Argv[i] + 2;
982 else
983 Arg = Argv[i] + 1;
984 if (Arg == "M") {
985 MRI = true;
986 } else if (MatchFlagWithArg("format")) {
987 FormatType = StringSwitch<Format>(match)
988 .Case("default", Default)
989 .Case("gnu", GNU)
990 .Case("darwin", DARWIN)
991 .Case("bsd", BSD)
992 .Default(Unknown);
993 if (FormatType == Unknown)
994 fail(std::string("Invalid format ") + match);
995 } else if (MatchFlagWithArg("plugin")) {
996 // Ignored.
997 } else {
998 Options += Argv[i] + 1;
999 }
1000 } else if (Options.empty()) {
1001 Options += Argv[i];
1002 } else {
1003 PositionalArgs.push_back(Argv[i]);
1004 }
1005 }
1006 ArchiveOperation Operation = parseCommandLine();
1007 return performOperation(Operation, nullptr);
1008}
1009
1010static int ranlib_main(int argc, char **argv) {
1011 bool ArchiveSpecified = false;
1012 for (int i = 1; i < argc; ++i) {
1013 if (handleGenericOption(argv[i])) {
1014 return 0;
1015 } else {
1016 if (ArchiveSpecified)
1017 fail("Exactly one archive should be specified");
1018 ArchiveSpecified = true;
1019 ArchiveName = argv[i];
1020 }
1021 }
1022 return performOperation(CreateSymTab, nullptr);
1023}
1024
1025int main(int argc, char **argv) {
1026 InitLLVM X(argc, argv);
1027 ToolName = argv[0];
1028
1029 llvm::InitializeAllTargetInfos();
1030 llvm::InitializeAllTargetMCs();
1031 llvm::InitializeAllAsmParsers();
1032
1033 Stem = sys::path::stem(ToolName);
1034 if (Stem.contains_lower("dlltool"))
1035 return dlltoolDriverMain(makeArrayRef(argv, argc));
1036
1037 if (Stem.contains_lower("ranlib"))
1038 return ranlib_main(argc, argv);
1039
1040 if (Stem.contains_lower("lib"))
1041 return libDriverMain(makeArrayRef(argv, argc));
1042
1043 if (Stem.contains_lower("ar"))
1044 return ar_main(argc, argv);
1045 fail("Not ranlib, ar, lib or dlltool!");
1046}
←

/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines an API used to report recoverable errors.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_ERROR_H
15#define LLVM_SUPPORT_ERROR_H
16
17#include "llvm-c/Error.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/ADT/StringExtras.h"
21#include "llvm/ADT/Twine.h"
22#include "llvm/Config/abi-breaking.h"
23#include "llvm/Support/AlignOf.h"
24#include "llvm/Support/Compiler.h"
25#include "llvm/Support/Debug.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/ErrorOr.h"
28#include "llvm/Support/Format.h"
29#include "llvm/Support/raw_ostream.h"
30#include <algorithm>
31#include <cassert>
32#include <cstdint>
33#include <cstdlib>
34#include <functional>
35#include <memory>
36#include <new>
37#include <string>
38#include <system_error>
39#include <type_traits>
40#include <utility>
41#include <vector>
42
43namespace llvm {
44
45class ErrorSuccess;
46
47/// Base class for error info classes. Do not extend this directly: Extend
48/// the ErrorInfo template subclass instead.
49class ErrorInfoBase {
50public:
51 virtual ~ErrorInfoBase() = default;
52
53 /// Print an error message to an output stream.
54 virtual void log(raw_ostream &OS) const = 0;
55
56 /// Return the error message as a string.
57 virtual std::string message() const {
58 std::string Msg;
59 raw_string_ostream OS(Msg);
60 log(OS);
61 return OS.str();
62 }
63
64 /// Convert this error to a std::error_code.
65 ///
66 /// This is a temporary crutch to enable interaction with code still
67 /// using std::error_code. It will be removed in the future.
68 virtual std::error_code convertToErrorCode() const = 0;
69
70 // Returns the class ID for this type.
71 static const void *classID() { return &ID; }
72
73 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
74 virtual const void *dynamicClassID() const = 0;
75
76 // Check whether this instance is a subclass of the class identified by
77 // ClassID.
78 virtual bool isA(const void *const ClassID) const {
79 return ClassID == classID();
80 }
81
82 // Check whether this instance is a subclass of ErrorInfoT.
83 template <typename ErrorInfoT> bool isA() const {
84 return isA(ErrorInfoT::classID());
85 }
86
87private:
88 virtual void anchor();
89
90 static char ID;
91};
92
93/// Lightweight error class with error context and mandatory checking.
94///
95/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
96/// are represented by setting the pointer to a ErrorInfoBase subclass
97/// instance containing information describing the failure. Success is
98/// represented by a null pointer value.
99///
100/// Instances of Error also contains a 'Checked' flag, which must be set
101/// before the destructor is called, otherwise the destructor will trigger a
102/// runtime error. This enforces at runtime the requirement that all Error
103/// instances be checked or returned to the caller.
104///
105/// There are two ways to set the checked flag, depending on what state the
106/// Error instance is in. For Error instances indicating success, it
107/// is sufficient to invoke the boolean conversion operator. E.g.:
108///
109/// @code{.cpp}
110/// Error foo(<...>);
111///
112/// if (auto E = foo(<...>))
113/// return E; // <- Return E if it is in the error state.
114/// // We have verified that E was in the success state. It can now be safely
115/// // destroyed.
116/// @endcode
117///
118/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
119/// without testing the return value will raise a runtime error, even if foo
120/// returns success.
121///
122/// For Error instances representing failure, you must use either the
123/// handleErrors or handleAllErrors function with a typed handler. E.g.:
124///
125/// @code{.cpp}
126/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
127/// // Custom error info.
128/// };
129///
130/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
131///
132/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
133/// auto NewE =
134/// handleErrors(E,
135/// [](const MyErrorInfo &M) {
136/// // Deal with the error.
137/// },
138/// [](std::unique_ptr<OtherError> M) -> Error {
139/// if (canHandle(*M)) {
140/// // handle error.
141/// return Error::success();
142/// }
143/// // Couldn't handle this error instance. Pass it up the stack.
144/// return Error(std::move(M));
145/// );
146/// // Note - we must check or return NewE in case any of the handlers
147/// // returned a new error.
148/// @endcode
149///
150/// The handleAllErrors function is identical to handleErrors, except
151/// that it has a void return type, and requires all errors to be handled and
152/// no new errors be returned. It prevents errors (assuming they can all be
153/// handled) from having to be bubbled all the way to the top-level.
154///
155/// *All* Error instances must be checked before destruction, even if
156/// they're moved-assigned or constructed from Success values that have already
157/// been checked. This enforces checking through all levels of the call stack.
158class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
159 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
160 // pointers out of this class to add to the error list.
161 friend class ErrorList;
162 friend class FileError;
163
164 // handleErrors needs to be able to set the Checked flag.
165 template <typename... HandlerTs>
166 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
167
168 // Expected<T> needs to be able to steal the payload when constructed from an
169 // error.
170 template <typename T> friend class Expected;
171
172 // wrap needs to be able to steal the payload.
173 friend LLVMErrorRef wrap(Error);
174
175protected:
176 /// Create a success value. Prefer using 'Error::success()' for readability
177 Error() {
178 setPtr(nullptr);
179 setChecked(false);
180 }
181
182public:
183 /// Create a success value.
184 static ErrorSuccess success();
185
186 // Errors are not copy-constructable.
187 Error(const Error &Other) = delete;
188
189 /// Move-construct an error value. The newly constructed error is considered
190 /// unchecked, even if the source error had been checked. The original error
191 /// becomes a checked Success value, regardless of its original state.
192 Error(Error &&Other) {
193 setChecked(true);
194 *this = std::move(Other);
195 }
196
197 /// Create an error value. Prefer using the 'make_error' function, but
198 /// this constructor can be useful when "re-throwing" errors from handlers.
199 Error(std::unique_ptr<ErrorInfoBase> Payload) {
200 setPtr(Payload.release());
201 setChecked(false);
22
←
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
202 }
203
204 // Errors are not copy-assignable.
205 Error &operator=(const Error &Other) = delete;
206
207 /// Move-assign an error value. The current error must represent success, you
208 /// you cannot overwrite an unhandled error. The current error is then
209 /// considered unchecked. The source error becomes a checked success value,
210 /// regardless of its original state.
211 Error &operator=(Error &&Other) {
212 // Don't allow overwriting of unchecked values.
213 assertIsChecked();
214 setPtr(Other.getPtr());
215
216 // This Error is unchecked, even if the source error was checked.
217 setChecked(false);
218
219 // Null out Other's payload and set its checked bit.
220 Other.setPtr(nullptr);
221 Other.setChecked(true);
222
223 return *this;
224 }
225
226 /// Destroy a Error. Fails with a call to abort() if the error is
227 /// unchecked.
228 ~Error() {
229 assertIsChecked();
230 delete getPtr();
231 }
232
233 /// Bool conversion. Returns true if this Error is in a failure state,
234 /// and false if it is in an accept state. If the error is in a Success state
235 /// it will be considered checked.
236 explicit operator bool() {
237 setChecked(getPtr() == nullptr);
238 return getPtr() != nullptr;
239 }
240
241 /// Check whether one error is a subclass of another.
242 template <typename ErrT> bool isA() const {
243 return getPtr() && getPtr()->isA(ErrT::classID());
244 }
245
246 /// Returns the dynamic class id of this error, or null if this is a success
247 /// value.
248 const void* dynamicClassID() const {
249 if (!getPtr())
250 return nullptr;
251 return getPtr()->dynamicClassID();
252 }
253
254private:
255#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
256 // assertIsChecked() happens very frequently, but under normal circumstances
257 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
258 // of debug prints can cause the function to be too large for inlining. So
259 // it's important that we define this function out of line so that it can't be
260 // inlined.
261 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
262 void fatalUncheckedError() const;
263#endif
264
265 void assertIsChecked() {
266#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
267 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
268 fatalUncheckedError();
269#endif
270 }
271
272 ErrorInfoBase *getPtr() const {
273 return reinterpret_cast<ErrorInfoBase*>(
274 reinterpret_cast<uintptr_t>(Payload) &
275 ~static_cast<uintptr_t>(0x1));
276 }
277
278 void setPtr(ErrorInfoBase *EI) {
279#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
280 Payload = reinterpret_cast<ErrorInfoBase*>(
281 (reinterpret_cast<uintptr_t>(EI) &
282 ~static_cast<uintptr_t>(0x1)) |
283 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
284#else
285 Payload = EI;
286#endif
287 }
288
289 bool getChecked() const {
290#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
291 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
292#else
293 return true;
294#endif
295 }
296
297 void setChecked(bool V) {
298 Payload = reinterpret_cast<ErrorInfoBase*>(
299 (reinterpret_cast<uintptr_t>(Payload) &
300 ~static_cast<uintptr_t>(0x1)) |
301 (V ? 0 : 1));
302 }
303
304 std::unique_ptr<ErrorInfoBase> takePayload() {
305 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
306 setPtr(nullptr);
307 setChecked(true);
308 return Tmp;
309 }
310
311 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
312 if (auto P = E.getPtr())
313 P->log(OS);
314 else
315 OS << "success";
316 return OS;
317 }
318
319 ErrorInfoBase *Payload = nullptr;
320};
321
322/// Subclass of Error for the sole purpose of identifying the success path in
323/// the type system. This allows to catch invalid conversion to Expected<T> at
324/// compile time.
325class ErrorSuccess final : public Error {};
326
327inline ErrorSuccess Error::success() { return ErrorSuccess(); }
328
329/// Make a Error instance representing failure using the given error info
330/// type.
331template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
332 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
333}
334
335/// Base class for user error types. Users should declare their error types
336/// like:
337///
338/// class MyError : public ErrorInfo<MyError> {
339/// ....
340/// };
341///
342/// This class provides an implementation of the ErrorInfoBase::kind
343/// method, which is used by the Error RTTI system.
344template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
345class ErrorInfo : public ParentErrT {
346public:
347 using ParentErrT::ParentErrT; // inherit constructors
348
349 static const void *classID() { return &ThisErrT::ID; }
350
351 const void *dynamicClassID() const override { return &ThisErrT::ID; }
352
353 bool isA(const void *const ClassID) const override {
354 return ClassID == classID() || ParentErrT::isA(ClassID);
355 }
356};
357
358/// Special ErrorInfo subclass representing a list of ErrorInfos.
359/// Instances of this class are constructed by joinError.
360class ErrorList final : public ErrorInfo<ErrorList> {
361 // handleErrors needs to be able to iterate the payload list of an
362 // ErrorList.
363 template <typename... HandlerTs>
364 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
365
366 // joinErrors is implemented in terms of join.
367 friend Error joinErrors(Error, Error);
368
369public:
370 void log(raw_ostream &OS) const override {
371 OS << "Multiple errors:\n";
372 for (auto &ErrPayload : Payloads) {
373 ErrPayload->log(OS);
374 OS << "\n";
375 }
376 }
377
378 std::error_code convertToErrorCode() const override;
379
380 // Used by ErrorInfo::classID.
381 static char ID;
382
383private:
384 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
385 std::unique_ptr<ErrorInfoBase> Payload2) {
386 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
387 "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__));
388 Payloads.push_back(std::move(Payload1));
389 Payloads.push_back(std::move(Payload2));
390 }
391
392 static Error join(Error E1, Error E2) {
393 if (!E1)
14
←
Taking false branch
→
394 return E2;
395 if (!E2)
15
←
Taking false branch
→
396 return E1;
397 if (E1.isA<ErrorList>()) {
16
←
Assuming the condition is false
→
17
←
Taking false branch
→
398 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
399 if (E2.isA<ErrorList>()) {
400 auto E2Payload = E2.takePayload();
401 auto &E2List = static_cast<ErrorList &>(*E2Payload);
402 for (auto &Payload : E2List.Payloads)
403 E1List.Payloads.push_back(std::move(Payload));
404 } else
405 E1List.Payloads.push_back(E2.takePayload());
406
407 return E1;
408 }
409 if (E2.isA<ErrorList>()) {
18
←
Assuming the condition is false
→
19
←
Taking false branch
→
410 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
411 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
412 return E2;
413 }
414 return Error(std::unique_ptr<ErrorList>(
21
←
Calling constructor for 'Error'
→
415 new ErrorList(E1.takePayload(), E2.takePayload())));
20
←
Memory is allocated
→
416 }
417
418 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
419};
420
421/// Concatenate errors. The resulting Error is unchecked, and contains the
422/// ErrorInfo(s), if any, contained in E1, followed by the
423/// ErrorInfo(s), if any, contained in E2.
424inline Error joinErrors(Error E1, Error E2) {
425 return ErrorList::join(std::move(E1), std::move(E2));
426}
427
428/// Tagged union holding either a T or a Error.
429///
430/// This class parallels ErrorOr, but replaces error_code with Error. Since
431/// Error cannot be copied, this class replaces getError() with
432/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
433/// error class type.
434template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
435 template <class T1> friend class ExpectedAsOutParameter;
436 template <class OtherT> friend class Expected;
437
438 static const bool isRef = std::is_reference<T>::value;
439
440 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
441
442 using error_type = std::unique_ptr<ErrorInfoBase>;
443
444public:
445 using storage_type = typename std::conditional<isRef, wrap, T>::type;
446 using value_type = T;
447
448private:
449 using reference = typename std::remove_reference<T>::type &;
450 using const_reference = const typename std::remove_reference<T>::type &;
451 using pointer = typename std::remove_reference<T>::type *;
452 using const_pointer = const typename std::remove_reference<T>::type *;
453
454public:
455 /// Create an Expected<T> error value from the given Error.
456 Expected(Error Err)
457 : HasError(true)
458#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
459 // Expected is unchecked upon construction in Debug builds.
460 , Unchecked(true)
461#endif
462 {
463 assert(Err && "Cannot create Expected<T> from Error success value.")((Err && "Cannot create Expected<T> from Error success value."
) ? static_cast<void> (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 463, __PRETTY_FUNCTION__));
464 new (getErrorStorage()) error_type(Err.takePayload());
465 }
466
467 /// Forbid to convert from Error::success() implicitly, this avoids having
468 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
469 /// but triggers the assertion above.
470 Expected(ErrorSuccess) = delete;
471
472 /// Create an Expected<T> success value from the given OtherT value, which
473 /// must be convertible to T.
474 template <typename OtherT>
475 Expected(OtherT &&Val,
476 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
477 * = nullptr)
478 : HasError(false)
479#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
480 // Expected is unchecked upon construction in Debug builds.
481 , Unchecked(true)
482#endif
483 {
484 new (getStorage()) storage_type(std::forward<OtherT>(Val));
485 }
486
487 /// Move construct an Expected<T> value.
488 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
489
490 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
491 /// must be convertible to T.
492 template <class OtherT>
493 Expected(Expected<OtherT> &&Other,
494 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
495 * = nullptr) {
496 moveConstruct(std::move(Other));
497 }
498
499 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
500 /// isn't convertible to T.
501 template <class OtherT>
502 explicit Expected(
503 Expected<OtherT> &&Other,
504 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
505 nullptr) {
506 moveConstruct(std::move(Other));
507 }
508
509 /// Move-assign from another Expected<T>.
510 Expected &operator=(Expected &&Other) {
511 moveAssign(std::move(Other));
512 return *this;
513 }
514
515 /// Destroy an Expected<T>.
516 ~Expected() {
517 assertIsChecked();
518 if (!HasError)
519 getStorage()->~storage_type();
520 else
521 getErrorStorage()->~error_type();
522 }
523
524 /// Return false if there is an error.
525 explicit operator bool() {
526#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
527 Unchecked = HasError;
528#endif
529 return !HasError;
530 }
531
532 /// Returns a reference to the stored T value.
533 reference get() {
534 assertIsChecked();
535 return *getStorage();
536 }
537
538 /// Returns a const reference to the stored T value.
539 const_reference get() const {
540 assertIsChecked();
541 return const_cast<Expected<T> *>(this)->get();
542 }
543
544 /// Check that this Expected<T> is an error of type ErrT.
545 template <typename ErrT> bool errorIsA() const {
546 return HasError && (*getErrorStorage())->template isA<ErrT>();
547 }
548
549 /// Take ownership of the stored error.
550 /// After calling this the Expected<T> is in an indeterminate state that can
551 /// only be safely destructed. No further calls (beside the destructor) should
552 /// be made on the Expected<T> vaule.
553 Error takeError() {
554#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
555 Unchecked = false;
556#endif
557 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
558 }
559
560 /// Returns a pointer to the stored T value.
561 pointer operator->() {
562 assertIsChecked();
563 return toPointer(getStorage());
564 }
565
566 /// Returns a const pointer to the stored T value.
567 const_pointer operator->() const {
568 assertIsChecked();
569 return toPointer(getStorage());
570 }
571
572 /// Returns a reference to the stored T value.
573 reference operator*() {
574 assertIsChecked();
575 return *getStorage();
576 }
577
578 /// Returns a const reference to the stored T value.
579 const_reference operator*() const {
580 assertIsChecked();
581 return *getStorage();
582 }
583
584private:
585 template <class T1>
586 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
587 return &a == &b;
588 }
589
590 template <class T1, class T2>
591 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
592 return false;
593 }
594
595 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
596 HasError = Other.HasError;
597#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
598 Unchecked = true;
599 Other.Unchecked = false;
600#endif
601
602 if (!HasError)
603 new (getStorage()) storage_type(std::move(*Other.getStorage()));
604 else
605 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
606 }
607
608 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
609 assertIsChecked();
610
611 if (compareThisIfSameType(*this, Other))
612 return;
613
614 this->~Expected();
615 new (this) Expected(std::move(Other));
616 }
617
618 pointer toPointer(pointer Val) { return Val; }
619
620 const_pointer toPointer(const_pointer Val) const { return Val; }
621
622 pointer toPointer(wrap *Val) { return &Val->get(); }
623
624 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
625
626 storage_type *getStorage() {
627 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 627, __PRETTY_FUNCTION__));
628 return reinterpret_cast<storage_type *>(TStorage.buffer);
629 }
630
631 const storage_type *getStorage() const {
632 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 632, __PRETTY_FUNCTION__));
633 return reinterpret_cast<const storage_type *>(TStorage.buffer);
634 }
635
636 error_type *getErrorStorage() {
637 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 637, __PRETTY_FUNCTION__));
638 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
639 }
640
641 const error_type *getErrorStorage() const {
642 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 642, __PRETTY_FUNCTION__));
643 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
644 }
645
646 // Used by ExpectedAsOutParameter to reset the checked flag.
647 void setUnchecked() {
648#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
649 Unchecked = true;
650#endif
651 }
652
653#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
654 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
655 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
656 void fatalUncheckedExpected() const {
657 dbgs() << "Expected<T> must be checked before access or destruction.\n";
658 if (HasError) {
659 dbgs() << "Unchecked Expected<T> contained error:\n";
660 (*getErrorStorage())->log(dbgs());
661 } else
662 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
663 "values in success mode must still be checked prior to being "
664 "destroyed).\n";
665 abort();
666 }
667#endif
668
669 void assertIsChecked() {
670#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
671 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
672 fatalUncheckedExpected();
673#endif
674 }
675
676 union {
677 AlignedCharArrayUnion<storage_type> TStorage;
678 AlignedCharArrayUnion<error_type> ErrorStorage;
679 };
680 bool HasError : 1;
681#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
682 bool Unchecked : 1;
683#endif
684};
685
686/// Report a serious error, calling any installed error handler. See
687/// ErrorHandling.h.
688LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
689 bool gen_crash_diag = true);
690
691/// Report a fatal error if Err is a failure value.
692///
693/// This function can be used to wrap calls to fallible functions ONLY when it
694/// is known that the Error will always be a success value. E.g.
695///
696/// @code{.cpp}
697/// // foo only attempts the fallible operation if DoFallibleOperation is
698/// // true. If DoFallibleOperation is false then foo always returns
699/// // Error::success().
700/// Error foo(bool DoFallibleOperation);
701///
702/// cantFail(foo(false));
703/// @endcode
704inline void cantFail(Error Err, const char *Msg = nullptr) {
705 if (Err) {
706 if (!Msg)
707 Msg = "Failure value returned from cantFail wrapped call";
708 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 708);
709 }
710}
711
712/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
713/// returns the contained value.
714///
715/// This function can be used to wrap calls to fallible functions ONLY when it
716/// is known that the Error will always be a success value. E.g.
717///
718/// @code{.cpp}
719/// // foo only attempts the fallible operation if DoFallibleOperation is
720/// // true. If DoFallibleOperation is false then foo always returns an int.
721/// Expected<int> foo(bool DoFallibleOperation);
722///
723/// int X = cantFail(foo(false));
724/// @endcode
725template <typename T>
726T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
727 if (ValOrErr)
728 return std::move(*ValOrErr);
729 else {
730 if (!Msg)
731 Msg = "Failure value returned from cantFail wrapped call";
732 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 732);
733 }
734}
735
736/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
737/// returns the contained reference.
738///
739/// This function can be used to wrap calls to fallible functions ONLY when it
740/// is known that the Error will always be a success value. E.g.
741///
742/// @code{.cpp}
743/// // foo only attempts the fallible operation if DoFallibleOperation is
744/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
745/// Expected<Bar&> foo(bool DoFallibleOperation);
746///
747/// Bar &X = cantFail(foo(false));
748/// @endcode
749template <typename T>
750T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
751 if (ValOrErr)
752 return *ValOrErr;
753 else {
754 if (!Msg)
755 Msg = "Failure value returned from cantFail wrapped call";
756 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 756);
757 }
758}
759
760/// Helper for testing applicability of, and applying, handlers for
761/// ErrorInfo types.
762template <typename HandlerT>
763class ErrorHandlerTraits
764 : public ErrorHandlerTraits<decltype(
765 &std::remove_reference<HandlerT>::type::operator())> {};
766
767// Specialization functions of the form 'Error (const ErrT&)'.
768template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
769public:
770 static bool appliesTo(const ErrorInfoBase &E) {
771 return E.template isA<ErrT>();
772 }
773
774 template <typename HandlerT>
775 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
776 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 776, __PRETTY_FUNCTION__));
777 return H(static_cast<ErrT &>(*E));
778 }
779};
780
781// Specialization functions of the form 'void (const ErrT&)'.
782template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
783public:
784 static bool appliesTo(const ErrorInfoBase &E) {
785 return E.template isA<ErrT>();
786 }
787
788 template <typename HandlerT>
789 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
790 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 790, __PRETTY_FUNCTION__));
791 H(static_cast<ErrT &>(*E));
792 return Error::success();
793 }
794};
795
796/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
797template <typename ErrT>
798class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
799public:
800 static bool appliesTo(const ErrorInfoBase &E) {
801 return E.template isA<ErrT>();
802 }
803
804 template <typename HandlerT>
805 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
806 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 806, __PRETTY_FUNCTION__));
807 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
808 return H(std::move(SubE));
809 }
810};
811
812/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
813template <typename ErrT>
814class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
815public:
816 static bool appliesTo(const ErrorInfoBase &E) {
817 return E.template isA<ErrT>();
818 }
819
820 template <typename HandlerT>
821 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
822 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 822, __PRETTY_FUNCTION__));
823 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
824 H(std::move(SubE));
825 return Error::success();
826 }
827};
828
829// Specialization for member functions of the form 'RetT (const ErrT&)'.
830template <typename C, typename RetT, typename ErrT>
831class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
832 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
833
834// Specialization for member functions of the form 'RetT (const ErrT&) const'.
835template <typename C, typename RetT, typename ErrT>
836class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
837 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
838
839// Specialization for member functions of the form 'RetT (const ErrT&)'.
840template <typename C, typename RetT, typename ErrT>
841class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
842 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
843
844// Specialization for member functions of the form 'RetT (const ErrT&) const'.
845template <typename C, typename RetT, typename ErrT>
846class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
847 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
848
849/// Specialization for member functions of the form
850/// 'RetT (std::unique_ptr<ErrT>)'.
851template <typename C, typename RetT, typename ErrT>
852class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
853 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
854
855/// Specialization for member functions of the form
856/// 'RetT (std::unique_ptr<ErrT>) const'.
857template <typename C, typename RetT, typename ErrT>
858class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
859 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
860
861inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
862 return Error(std::move(Payload));
863}
864
865template <typename HandlerT, typename... HandlerTs>
866Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
867 HandlerT &&Handler, HandlerTs &&... Handlers) {
868 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
869 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
870 std::move(Payload));
871 return handleErrorImpl(std::move(Payload),
872 std::forward<HandlerTs>(Handlers)...);
873}
874
875/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
876/// unhandled errors (or Errors returned by handlers) are re-concatenated and
877/// returned.
878/// Because this function returns an error, its result must also be checked
879/// or returned. If you intend to handle all errors use handleAllErrors
880/// (which returns void, and will abort() on unhandled errors) instead.
881template <typename... HandlerTs>
882Error handleErrors(Error E, HandlerTs &&... Hs) {
883 if (!E)
10
←
Taking false branch
→
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
11
←
Assuming the condition is true
→
12
←
Taking true branch
→
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
13
←
Calling 'ErrorList::join'
→
893 std::move(R),
894 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
895 return R;
896 }
897
898 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
899}
900
901/// Behaves the same as handleErrors, except that by contract all errors
902/// *must* be handled by the given handlers (i.e. there must be no remaining
903/// errors after running the handlers, or llvm_unreachable is called).
904template <typename... HandlerTs>
905void handleAllErrors(Error E, HandlerTs &&... Handlers) {
906 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
9
←
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn345461/tools/llvm-ar/llvm-ar.cpp:137:33)>'
→
907}
908
909/// Check that E is a non-error, then drop it.
910/// If E is an error, llvm_unreachable will be called.
911inline void handleAllErrors(Error E) {
912 cantFail(std::move(E));
913}
914
915/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
916///
917/// If the incoming value is a success value it is returned unmodified. If it
918/// is a failure value then it the contained error is passed to handleErrors.
919/// If handleErrors is able to handle the error then the RecoveryPath functor
920/// is called to supply the final result. If handleErrors is not able to
921/// handle all errors then the unhandled errors are returned.
922///
923/// This utility enables the follow pattern:
924///
925/// @code{.cpp}
926/// enum FooStrategy { Aggressive, Conservative };
927/// Expected<Foo> foo(FooStrategy S);
928///
929/// auto ResultOrErr =
930/// handleExpected(
931/// foo(Aggressive),
932/// []() { return foo(Conservative); },
933/// [](AggressiveStrategyError&) {
934/// // Implicitly conusme this - we'll recover by using a conservative
935/// // strategy.
936/// });
937///
938/// @endcode
939template <typename T, typename RecoveryFtor, typename... HandlerTs>
940Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
941 HandlerTs &&... Handlers) {
942 if (ValOrErr)
943 return ValOrErr;
944
945 if (auto Err = handleErrors(ValOrErr.takeError(),
946 std::forward<HandlerTs>(Handlers)...))
947 return std::move(Err);
948
949 return RecoveryPath();
950}
951
952/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
953/// will be printed before the first one is logged. A newline will be printed
954/// after each error.
955///
956/// This is useful in the base level of your program to allow clean termination
957/// (allowing clean deallocation of resources, etc.), while reporting error
958/// information to the user.
959void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner);
960
961/// Write all error messages (if any) in E to a string. The newline character
962/// is used to separate error messages.
963inline std::string toString(Error E) {
964 SmallVector<std::string, 2> Errors;
965 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
966 Errors.push_back(EI.message());
967 });
968 return join(Errors.begin(), Errors.end(), "\n");
969}
970
971/// Consume a Error without doing anything. This method should be used
972/// only where an error can be considered a reasonable and expected return
973/// value.
974///
975/// Uses of this method are potentially indicative of design problems: If it's
976/// legitimate to do nothing while processing an "error", the error-producer
977/// might be more clearly refactored to return an Optional<T>.
978inline void consumeError(Error Err) {
979 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
980}
981
982/// Helper for converting an Error to a bool.
983///
984/// This method returns true if Err is in an error state, or false if it is
985/// in a success state. Puts Err in a checked state in both cases (unlike
986/// Error::operator bool(), which only does this for success states).
987inline bool errorToBool(Error Err) {
988 bool IsError = static_cast<bool>(Err);
989 if (IsError)
990 consumeError(std::move(Err));
991 return IsError;
992}
993
994/// Helper for Errors used as out-parameters.
995///
996/// This helper is for use with the Error-as-out-parameter idiom, where an error
997/// is passed to a function or method by reference, rather than being returned.
998/// In such cases it is helpful to set the checked bit on entry to the function
999/// so that the error can be written to (unchecked Errors abort on assignment)
1000/// and clear the checked bit on exit so that clients cannot accidentally forget
1001/// to check the result. This helper performs these actions automatically using
1002/// RAII:
1003///
1004/// @code{.cpp}
1005/// Result foo(Error &Err) {
1006/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1007/// // <body of foo>
1008/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1009/// }
1010/// @endcode
1011///
1012/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1013/// used with optional Errors (Error pointers that are allowed to be null). If
1014/// ErrorAsOutParameter took an Error reference, an instance would have to be
1015/// created inside every condition that verified that Error was non-null. By
1016/// taking an Error pointer we can just create one instance at the top of the
1017/// function.
1018class ErrorAsOutParameter {
1019public:
1020 ErrorAsOutParameter(Error *Err) : Err(Err) {
1021 // Raise the checked bit if Err is success.
1022 if (Err)
1023 (void)!!*Err;
1024 }
1025
1026 ~ErrorAsOutParameter() {
1027 // Clear the checked bit.
1028 if (Err && !*Err)
1029 *Err = Error::success();
1030 }
1031
1032private:
1033 Error *Err;
1034};
1035
1036/// Helper for Expected<T>s used as out-parameters.
1037///
1038/// See ErrorAsOutParameter.
1039template <typename T>
1040class ExpectedAsOutParameter {
1041public:
1042 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1043 : ValOrErr(ValOrErr) {
1044 if (ValOrErr)
1045 (void)!!*ValOrErr;
1046 }
1047
1048 ~ExpectedAsOutParameter() {
1049 if (ValOrErr)
1050 ValOrErr->setUnchecked();
1051 }
1052
1053private:
1054 Expected<T> *ValOrErr;
1055};
1056
1057/// This class wraps a std::error_code in a Error.
1058///
1059/// This is useful if you're writing an interface that returns a Error
1060/// (or Expected) and you want to call code that still returns
1061/// std::error_codes.
1062class ECError : public ErrorInfo<ECError> {
1063 friend Error errorCodeToError(std::error_code);
1064
1065public:
1066 void setErrorCode(std::error_code EC) { this->EC = EC; }
1067 std::error_code convertToErrorCode() const override { return EC; }
1068 void log(raw_ostream &OS) const override { OS << EC.message(); }
1069
1070 // Used by ErrorInfo::classID.
1071 static char ID;
1072
1073protected:
1074 ECError() = default;
1075 ECError(std::error_code EC) : EC(EC) {}
1076
1077 std::error_code EC;
1078};
1079
1080/// The value returned by this function can be returned from convertToErrorCode
1081/// for Error values where no sensible translation to std::error_code exists.
1082/// It should only be used in this situation, and should never be used where a
1083/// sensible conversion to std::error_code is available, as attempts to convert
1084/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1085///error to try to convert such a value).
1086std::error_code inconvertibleErrorCode();
1087
1088/// Helper for converting an std::error_code to a Error.
1089Error errorCodeToError(std::error_code EC);
1090
1091/// Helper for converting an ECError to a std::error_code.
1092///
1093/// This method requires that Err be Error() or an ECError, otherwise it
1094/// will trigger a call to abort().
1095std::error_code errorToErrorCode(Error Err);
1096
1097/// Convert an ErrorOr<T> to an Expected<T>.
1098template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1099 if (auto EC = EO.getError())
1100 return errorCodeToError(EC);
1101 return std::move(*EO);
1102}
1103
1104/// Convert an Expected<T> to an ErrorOr<T>.
1105template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1106 if (auto Err = E.takeError())
1107 return errorToErrorCode(std::move(Err));
1108 return std::move(*E);
1109}
1110
1111/// This class wraps a string in an Error.
1112///
1113/// StringError is useful in cases where the client is not expected to be able
1114/// to consume the specific error message programmatically (for example, if the
1115/// error message is to be presented to the user).
1116///
1117/// StringError can also be used when additional information is to be printed
1118/// along with a error_code message. Depending on the constructor called, this
1119/// class can either display:
1120/// 1. the error_code message (ECError behavior)
1121/// 2. a string
1122/// 3. the error_code message and a string
1123///
1124/// These behaviors are useful when subtyping is required; for example, when a
1125/// specific library needs an explicit error type. In the example below,
1126/// PDBError is derived from StringError:
1127///
1128/// @code{.cpp}
1129/// Expected<int> foo() {
1130/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1131/// "Additional information");
1132/// }
1133/// @endcode
1134///
1135class StringError : public ErrorInfo<StringError> {
1136public:
1137 static char ID;
1138
1139 // Prints EC + S and converts to EC
1140 StringError(std::error_code EC, const Twine &S = Twine());
1141
1142 // Prints S and converts to EC
1143 StringError(const Twine &S, std::error_code EC);
1144
1145 void log(raw_ostream &OS) const override;
1146 std::error_code convertToErrorCode() const override;
1147
1148 const std::string &getMessage() const { return Msg; }
1149
1150private:
1151 std::string Msg;
1152 std::error_code EC;
1153 const bool PrintMsgOnly = false;
1154};
1155
1156/// Create formatted StringError object.
1157template <typename... Ts>
1158Error createStringError(std::error_code EC, char const *Fmt,
1159 const Ts &... Vals) {
1160 std::string Buffer;
1161 raw_string_ostream Stream(Buffer);
1162 Stream << format(Fmt, Vals...);
1163 return make_error<StringError>(Stream.str(), EC);
1164}
1165
1166Error createStringError(std::error_code EC, char const *Msg);
1167
1168/// This class wraps a filename and another Error.
1169///
1170/// In some cases, an error needs to live along a 'source' name, in order to
1171/// show more detailed information to the user.
1172class FileError final : public ErrorInfo<FileError> {
1173
1174 friend Error createFileError(std::string, Error);
1175
1176public:
1177 void log(raw_ostream &OS) const override {
1178 assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()."
) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1178, __PRETTY_FUNCTION__));
1179 OS << "'" << FileName << "': ";
1180 Err->log(OS);
1181 }
1182
1183 Error takeError() { return Error(std::move(Err)); }
1184
1185 std::error_code convertToErrorCode() const override;
1186
1187 // Used by ErrorInfo::classID.
1188 static char ID;
1189
1190private:
1191 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1192 assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value."
) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1192, __PRETTY_FUNCTION__));
1193 assert(!F.empty() &&((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__))
1194 "The file name provided to FileError must not be empty.")((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__));
1195 FileName = F;
1196 Err = std::move(E);
1197 }
1198
1199 static Error build(std::string F, Error E) {
1200 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1201 }
1202
1203 std::string FileName;
1204 std::unique_ptr<ErrorInfoBase> Err;
1205};
1206
1207/// Concatenate a source file path and/or name with an Error. The resulting
1208/// Error is unchecked.
1209inline Error createFileError(std::string F, Error E) {
1210 return FileError::build(F, std::move(E));
1211}
1212
1213Error createFileError(std::string F, ErrorSuccess) = delete;
1214
1215/// Helper for check-and-exit error handling.
1216///
1217/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1218///
1219class ExitOnError {
1220public:
1221 /// Create an error on exit helper.
1222 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1223 : Banner(std::move(Banner)),
1224 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1225
1226 /// Set the banner string for any errors caught by operator().
1227 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1228
1229 /// Set the exit-code mapper function.
1230 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1231 this->GetExitCode = std::move(GetExitCode);
1232 }
1233
1234 /// Check Err. If it's in a failure state log the error(s) and exit.
1235 void operator()(Error Err) const { checkError(std::move(Err)); }
1236
1237 /// Check E. If it's in a success state then return the contained value. If
1238 /// it's in a failure state log the error(s) and exit.
1239 template <typename T> T operator()(Expected<T> &&E) const {
1240 checkError(E.takeError());
1241 return std::move(*E);
1242 }
1243
1244 /// Check E. If it's in a success state then return the contained reference. If
1245 /// it's in a failure state log the error(s) and exit.
1246 template <typename T> T& operator()(Expected<T&> &&E) const {
1247 checkError(E.takeError());
1248 return *E;
1249 }
1250
1251private:
1252 void checkError(Error Err) const {
1253 if (Err) {
1254 int ExitCode = GetExitCode(Err);
1255 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1256 exit(ExitCode);
1257 }
1258 }
1259
1260 std::string Banner;
1261 std::function<int(const Error &)> GetExitCode;
1262};
1263
1264/// Conversion from Error to LLVMErrorRef for C error bindings.
1265inline LLVMErrorRef wrap(Error Err) {
1266 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1267}
1268
1269/// Conversion from LLVMErrorRef to Error for C error bindings.
1270inline Error unwrap(LLVMErrorRef ErrRef) {
1271 return Error(std::unique_ptr<ErrorInfoBase>(
1272 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1273}
1274
1275} // end namespace llvm
1276
1277#endif // LLVM_SUPPORT_ERROR_H