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 ArchiveWriter.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 -analyzer-config-compatibility-mode=true -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~svn350071/build-llvm/lib/Object -I /build/llvm-toolchain-snapshot-8~svn350071/lib/Object -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn350071/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~svn350071/build-llvm/lib/Object -fdebug-prefix-map=/build/llvm-toolchain-snapshot-8~svn350071=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-12-27-042839-1215-1 -x c++ /build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp

1//===- ArchiveWriter.cpp - ar File Format implementation --------*- 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 the writeArchive function.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Object/ArchiveWriter.h"
15#include "llvm/ADT/ArrayRef.h"
16#include "llvm/ADT/StringRef.h"
17#include "llvm/BinaryFormat/Magic.h"
18#include "llvm/IR/LLVMContext.h"
19#include "llvm/Object/Archive.h"
20#include "llvm/Object/ObjectFile.h"
21#include "llvm/Object/SymbolicFile.h"
22#include "llvm/Support/EndianStream.h"
23#include "llvm/Support/Errc.h"
24#include "llvm/Support/ErrorHandling.h"
25#include "llvm/Support/Format.h"
26#include "llvm/Support/Path.h"
27#include "llvm/Support/ToolOutputFile.h"
28#include "llvm/Support/raw_ostream.h"
29
30#include <map>
31
32#if !defined(_MSC_VER) && !defined(__MINGW32__)
33#include <unistd.h>
34#else
35#include <io.h>
36#endif
37
38using namespace llvm;
39
40NewArchiveMember::NewArchiveMember(MemoryBufferRef BufRef)
41 : Buf(MemoryBuffer::getMemBuffer(BufRef, false)),
42 MemberName(BufRef.getBufferIdentifier()) {}
43
44Expected<NewArchiveMember>
45NewArchiveMember::getOldMember(const object::Archive::Child &OldMember,
46 bool Deterministic) {
47 Expected<llvm::MemoryBufferRef> BufOrErr = OldMember.getMemoryBufferRef();
48 if (!BufOrErr)
49 return BufOrErr.takeError();
50
51 NewArchiveMember M;
52 assert(M.IsNew == false)((M.IsNew == false) ? static_cast<void> (0) : __assert_fail
("M.IsNew == false", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 52, __PRETTY_FUNCTION__))
;
53 M.Buf = MemoryBuffer::getMemBuffer(*BufOrErr, false);
54 M.MemberName = M.Buf->getBufferIdentifier();
55 if (!Deterministic) {
56 auto ModTimeOrErr = OldMember.getLastModified();
57 if (!ModTimeOrErr)
58 return ModTimeOrErr.takeError();
59 M.ModTime = ModTimeOrErr.get();
60 Expected<unsigned> UIDOrErr = OldMember.getUID();
61 if (!UIDOrErr)
62 return UIDOrErr.takeError();
63 M.UID = UIDOrErr.get();
64 Expected<unsigned> GIDOrErr = OldMember.getGID();
65 if (!GIDOrErr)
66 return GIDOrErr.takeError();
67 M.GID = GIDOrErr.get();
68 Expected<sys::fs::perms> AccessModeOrErr = OldMember.getAccessMode();
69 if (!AccessModeOrErr)
70 return AccessModeOrErr.takeError();
71 M.Perms = AccessModeOrErr.get();
72 }
73 return std::move(M);
74}
75
76Expected<NewArchiveMember> NewArchiveMember::getFile(StringRef FileName,
77 bool Deterministic) {
78 sys::fs::file_status Status;
79 int FD;
80 if (auto EC = sys::fs::openFileForRead(FileName, FD))
81 return errorCodeToError(EC);
82 assert(FD != -1)((FD != -1) ? static_cast<void> (0) : __assert_fail ("FD != -1"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 82, __PRETTY_FUNCTION__))
;
83
84 if (auto EC = sys::fs::status(FD, Status))
85 return errorCodeToError(EC);
86
87 // Opening a directory doesn't make sense. Let it fail.
88 // Linux cannot open directories with open(2), although
89 // cygwin and *bsd can.
90 if (Status.type() == sys::fs::file_type::directory_file)
91 return errorCodeToError(make_error_code(errc::is_a_directory));
92
93 ErrorOr<std::unique_ptr<MemoryBuffer>> MemberBufferOrErr =
94 MemoryBuffer::getOpenFile(FD, FileName, Status.getSize(), false);
95 if (!MemberBufferOrErr)
96 return errorCodeToError(MemberBufferOrErr.getError());
97
98 if (close(FD) != 0)
99 return errorCodeToError(std::error_code(errno(*__errno_location ()), std::generic_category()));
100
101 NewArchiveMember M;
102 M.IsNew = true;
103 M.Buf = std::move(*MemberBufferOrErr);
104 M.MemberName = M.Buf->getBufferIdentifier();
105 if (!Deterministic) {
106 M.ModTime = std::chrono::time_point_cast<std::chrono::seconds>(
107 Status.getLastModificationTime());
108 M.UID = Status.getUser();
109 M.GID = Status.getGroup();
110 M.Perms = Status.permissions();
111 }
112 return std::move(M);
113}
114
115template <typename T>
116static void printWithSpacePadding(raw_ostream &OS, T Data, unsigned Size) {
117 uint64_t OldPos = OS.tell();
118 OS << Data;
119 unsigned SizeSoFar = OS.tell() - OldPos;
120 assert(SizeSoFar <= Size && "Data doesn't fit in Size")((SizeSoFar <= Size && "Data doesn't fit in Size")
? static_cast<void> (0) : __assert_fail ("SizeSoFar <= Size && \"Data doesn't fit in Size\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 120, __PRETTY_FUNCTION__))
;
121 OS.indent(Size - SizeSoFar);
122}
123
124static bool isDarwin(object::Archive::Kind Kind) {
125 return Kind == object::Archive::K_DARWIN ||
126 Kind == object::Archive::K_DARWIN64;
127}
128
129static bool isBSDLike(object::Archive::Kind Kind) {
130 switch (Kind) {
131 case object::Archive::K_GNU:
132 case object::Archive::K_GNU64:
133 return false;
134 case object::Archive::K_BSD:
135 case object::Archive::K_DARWIN:
136 case object::Archive::K_DARWIN64:
137 return true;
138 case object::Archive::K_COFF:
139 break;
140 }
141 llvm_unreachable("not supported for writting")::llvm::llvm_unreachable_internal("not supported for writting"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 141)
;
142}
143
144template <class T>
145static void print(raw_ostream &Out, object::Archive::Kind Kind, T Val) {
146 support::endian::write(Out, Val,
147 isBSDLike(Kind) ? support::little : support::big);
148}
149
150static void printRestOfMemberHeader(
151 raw_ostream &Out, const sys::TimePoint<std::chrono::seconds> &ModTime,
152 unsigned UID, unsigned GID, unsigned Perms, unsigned Size) {
153 printWithSpacePadding(Out, sys::toTimeT(ModTime), 12);
154
155 // The format has only 6 chars for uid and gid. Truncate if the provided
156 // values don't fit.
157 printWithSpacePadding(Out, UID % 1000000, 6);
158 printWithSpacePadding(Out, GID % 1000000, 6);
159
160 printWithSpacePadding(Out, format("%o", Perms), 8);
161 printWithSpacePadding(Out, Size, 10);
162 Out << "`\n";
163}
164
165static void
166printGNUSmallMemberHeader(raw_ostream &Out, StringRef Name,
167 const sys::TimePoint<std::chrono::seconds> &ModTime,
168 unsigned UID, unsigned GID, unsigned Perms,
169 unsigned Size) {
170 printWithSpacePadding(Out, Twine(Name) + "/", 16);
171 printRestOfMemberHeader(Out, ModTime, UID, GID, Perms, Size);
172}
173
174static void
175printBSDMemberHeader(raw_ostream &Out, uint64_t Pos, StringRef Name,
176 const sys::TimePoint<std::chrono::seconds> &ModTime,
177 unsigned UID, unsigned GID, unsigned Perms,
178 unsigned Size) {
179 uint64_t PosAfterHeader = Pos + 60 + Name.size();
180 // Pad so that even 64 bit object files are aligned.
181 unsigned Pad = OffsetToAlignment(PosAfterHeader, 8);
182 unsigned NameWithPadding = Name.size() + Pad;
183 printWithSpacePadding(Out, Twine("#1/") + Twine(NameWithPadding), 16);
184 printRestOfMemberHeader(Out, ModTime, UID, GID, Perms,
185 NameWithPadding + Size);
186 Out << Name;
187 while (Pad--)
188 Out.write(uint8_t(0));
189}
190
191static bool useStringTable(bool Thin, StringRef Name) {
192 return Thin || Name.size() >= 16 || Name.contains('/');
193}
194
195// Compute the relative path from From to To.
196static std::string computeRelativePath(StringRef From, StringRef To) {
197 if (sys::path::is_absolute(From) || sys::path::is_absolute(To))
198 return To;
199
200 StringRef DirFrom = sys::path::parent_path(From);
201 auto FromI = sys::path::begin(DirFrom);
202 auto ToI = sys::path::begin(To);
203 while (*FromI == *ToI) {
204 ++FromI;
205 ++ToI;
206 }
207
208 SmallString<128> Relative;
209 for (auto FromE = sys::path::end(DirFrom); FromI != FromE; ++FromI)
210 sys::path::append(Relative, "..");
211
212 for (auto ToE = sys::path::end(To); ToI != ToE; ++ToI)
213 sys::path::append(Relative, *ToI);
214
215#ifdef _WIN32
216 // Replace backslashes with slashes so that the path is portable between *nix
217 // and Windows.
218 std::replace(Relative.begin(), Relative.end(), '\\', '/');
219#endif
220
221 return Relative.str();
222}
223
224static bool is64BitKind(object::Archive::Kind Kind) {
225 switch (Kind) {
226 case object::Archive::K_GNU:
227 case object::Archive::K_BSD:
228 case object::Archive::K_DARWIN:
229 case object::Archive::K_COFF:
230 return false;
231 case object::Archive::K_DARWIN64:
232 case object::Archive::K_GNU64:
233 return true;
234 }
235 llvm_unreachable("not supported for writting")::llvm::llvm_unreachable_internal("not supported for writting"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 235)
;
236}
237
238static void addToStringTable(raw_ostream &Out, StringRef ArcName,
239 const NewArchiveMember &M, bool Thin) {
240 StringRef ID = M.Buf->getBufferIdentifier();
241 if (Thin) {
242 if (M.IsNew)
243 Out << computeRelativePath(ArcName, ID);
244 else
245 Out << ID;
246 } else
247 Out << M.MemberName;
248 Out << "/\n";
249}
250
251static void printMemberHeader(raw_ostream &Out, uint64_t Pos,
252 raw_ostream &StringTable,
253 StringMap<uint64_t> &MemberNames,
254 object::Archive::Kind Kind, bool Thin,
255 StringRef ArcName, const NewArchiveMember &M,
256 sys::TimePoint<std::chrono::seconds> ModTime,
257 unsigned Size) {
258
259 if (isBSDLike(Kind))
260 return printBSDMemberHeader(Out, Pos, M.MemberName, ModTime, M.UID, M.GID,
261 M.Perms, Size);
262 if (!useStringTable(Thin, M.MemberName))
263 return printGNUSmallMemberHeader(Out, M.MemberName, ModTime, M.UID, M.GID,
264 M.Perms, Size);
265 Out << '/';
266 uint64_t NamePos;
267 if (Thin) {
268 NamePos = StringTable.tell();
269 addToStringTable(StringTable, ArcName, M, Thin);
270 } else {
271 auto Insertion = MemberNames.insert({M.MemberName, uint64_t(0)});
272 if (Insertion.second) {
273 Insertion.first->second = StringTable.tell();
274 addToStringTable(StringTable, ArcName, M, Thin);
275 }
276 NamePos = Insertion.first->second;
277 }
278 printWithSpacePadding(Out, NamePos, 15);
279 printRestOfMemberHeader(Out, ModTime, M.UID, M.GID, M.Perms, Size);
280}
281
282namespace {
283struct MemberData {
284 std::vector<unsigned> Symbols;
285 std::string Header;
286 StringRef Data;
287 StringRef Padding;
288};
289} // namespace
290
291static MemberData computeStringTable(StringRef Names) {
292 unsigned Size = Names.size();
293 unsigned Pad = OffsetToAlignment(Size, 2);
294 std::string Header;
295 raw_string_ostream Out(Header);
296 printWithSpacePadding(Out, "//", 48);
297 printWithSpacePadding(Out, Size + Pad, 10);
298 Out << "`\n";
299 Out.flush();
300 return {{}, std::move(Header), Names, Pad ? "\n" : ""};
301}
302
303static sys::TimePoint<std::chrono::seconds> now(bool Deterministic) {
304 using namespace std::chrono;
305
306 if (!Deterministic)
307 return time_point_cast<seconds>(system_clock::now());
308 return sys::TimePoint<seconds>();
309}
310
311static bool isArchiveSymbol(const object::BasicSymbolRef &S) {
312 uint32_t Symflags = S.getFlags();
313 if (Symflags & object::SymbolRef::SF_FormatSpecific)
314 return false;
315 if (!(Symflags & object::SymbolRef::SF_Global))
316 return false;
317 if (Symflags & object::SymbolRef::SF_Undefined)
318 return false;
319 return true;
320}
321
322static void printNBits(raw_ostream &Out, object::Archive::Kind Kind,
323 uint64_t Val) {
324 if (is64BitKind(Kind))
325 print<uint64_t>(Out, Kind, Val);
326 else
327 print<uint32_t>(Out, Kind, Val);
328}
329
330static void writeSymbolTable(raw_ostream &Out, object::Archive::Kind Kind,
331 bool Deterministic, ArrayRef<MemberData> Members,
332 StringRef StringTable) {
333 // We don't write a symbol table on an archive with no members -- except on
334 // Darwin, where the linker will abort unless the archive has a symbol table.
335 if (StringTable.empty() && !isDarwin(Kind))
336 return;
337
338 unsigned NumSyms = 0;
339 for (const MemberData &M : Members)
340 NumSyms += M.Symbols.size();
341
342 unsigned Size = 0;
343 unsigned OffsetSize = is64BitKind(Kind) ? sizeof(uint64_t) : sizeof(uint32_t);
344
345 Size += OffsetSize; // Number of entries
346 if (isBSDLike(Kind))
347 Size += NumSyms * OffsetSize * 2; // Table
348 else
349 Size += NumSyms * OffsetSize; // Table
350 if (isBSDLike(Kind))
351 Size += OffsetSize; // byte count
352 Size += StringTable.size();
353 // ld64 expects the members to be 8-byte aligned for 64-bit content and at
354 // least 4-byte aligned for 32-bit content. Opt for the larger encoding
355 // uniformly.
356 // We do this for all bsd formats because it simplifies aligning members.
357 unsigned Alignment = isBSDLike(Kind) ? 8 : 2;
358 unsigned Pad = OffsetToAlignment(Size, Alignment);
359 Size += Pad;
360
361 if (isBSDLike(Kind)) {
362 const char *Name = is64BitKind(Kind) ? "__.SYMDEF_64" : "__.SYMDEF";
363 printBSDMemberHeader(Out, Out.tell(), Name, now(Deterministic), 0, 0, 0,
364 Size);
365 } else {
366 const char *Name = is64BitKind(Kind) ? "/SYM64" : "";
367 printGNUSmallMemberHeader(Out, Name, now(Deterministic), 0, 0, 0, Size);
368 }
369
370 uint64_t Pos = Out.tell() + Size;
371
372 if (isBSDLike(Kind))
373 printNBits(Out, Kind, NumSyms * 2 * OffsetSize);
374 else
375 printNBits(Out, Kind, NumSyms);
376
377 for (const MemberData &M : Members) {
378 for (unsigned StringOffset : M.Symbols) {
379 if (isBSDLike(Kind))
380 printNBits(Out, Kind, StringOffset);
381 printNBits(Out, Kind, Pos); // member offset
382 }
383 Pos += M.Header.size() + M.Data.size() + M.Padding.size();
384 }
385
386 if (isBSDLike(Kind))
387 // byte count of the string table
388 printNBits(Out, Kind, StringTable.size());
389 Out << StringTable;
390
391 while (Pad--)
392 Out.write(uint8_t(0));
393}
394
395static Expected<std::vector<unsigned>>
396getSymbols(MemoryBufferRef Buf, raw_ostream &SymNames, bool &HasObject) {
397 std::vector<unsigned> Ret;
398
399 // In the scenario when LLVMContext is populated SymbolicFile will contain a
400 // reference to it, thus SymbolicFile should be destroyed first.
401 LLVMContext Context;
402 std::unique_ptr<object::SymbolicFile> Obj;
403 if (identify_magic(Buf.getBuffer()) == file_magic::bitcode) {
11
Assuming the condition is true
12
Taking true branch
404 auto ObjOrErr = object::SymbolicFile::createSymbolicFile(
405 Buf, file_magic::bitcode, &Context);
406 if (!ObjOrErr) {
13
Taking true branch
407 // FIXME: check only for "not an object file" errors.
408 consumeError(ObjOrErr.takeError());
14
Calling 'consumeError'
409 return Ret;
410 }
411 Obj = std::move(*ObjOrErr);
412 } else {
413 auto ObjOrErr = object::SymbolicFile::createSymbolicFile(Buf);
414 if (!ObjOrErr) {
415 // FIXME: check only for "not an object file" errors.
416 consumeError(ObjOrErr.takeError());
417 return Ret;
418 }
419 Obj = std::move(*ObjOrErr);
420 }
421
422 HasObject = true;
423 for (const object::BasicSymbolRef &S : Obj->symbols()) {
424 if (!isArchiveSymbol(S))
425 continue;
426 Ret.push_back(SymNames.tell());
427 if (auto EC = S.printName(SymNames))
428 return errorCodeToError(EC);
429 SymNames << '\0';
430 }
431 return Ret;
432}
433
434static Expected<std::vector<MemberData>>
435computeMemberData(raw_ostream &StringTable, raw_ostream &SymNames,
436 object::Archive::Kind Kind, bool Thin, StringRef ArcName,
437 bool Deterministic, ArrayRef<NewArchiveMember> NewMembers) {
438 static char PaddingData[8] = {'\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'};
439
440 // This ignores the symbol table, but we only need the value mod 8 and the
441 // symbol table is aligned to be a multiple of 8 bytes
442 uint64_t Pos = 0;
443
444 std::vector<MemberData> Ret;
445 bool HasObject = false;
446
447 // Deduplicate long member names in the string table and reuse earlier name
448 // offsets. This especially saves space for COFF Import libraries where all
449 // members have the same name.
450 StringMap<uint64_t> MemberNames;
451
452 // UniqueTimestamps is a special case to improve debugging on Darwin:
453 //
454 // The Darwin linker does not link debug info into the final
455 // binary. Instead, it emits entries of type N_OSO in in the output
456 // binary's symbol table, containing references to the linked-in
457 // object files. Using that reference, the debugger can read the
458 // debug data directly from the object files. Alternatively, an
459 // invocation of 'dsymutil' will link the debug data from the object
460 // files into a dSYM bundle, which can be loaded by the debugger,
461 // instead of the object files.
462 //
463 // For an object file, the N_OSO entries contain the absolute path
464 // path to the file, and the file's timestamp. For an object
465 // included in an archive, the path is formatted like
466 // "/absolute/path/to/archive.a(member.o)", and the timestamp is the
467 // archive member's timestamp, rather than the archive's timestamp.
468 //
469 // However, this doesn't always uniquely identify an object within
470 // an archive -- an archive file can have multiple entries with the
471 // same filename. (This will happen commonly if the original object
472 // files started in different directories.) The only way they get
473 // distinguished, then, is via the timestamp. But this process is
474 // unable to find the correct object file in the archive when there
475 // are two files of the same name and timestamp.
476 //
477 // Additionally, timestamp==0 is treated specially, and causes the
478 // timestamp to be ignored as a match criteria.
479 //
480 // That will "usually" work out okay when creating an archive not in
481 // deterministic timestamp mode, because the objects will probably
482 // have been created at different timestamps.
483 //
484 // To ameliorate this problem, in deterministic archive mode (which
485 // is the default), on Darwin we will emit a unique non-zero
486 // timestamp for each entry with a duplicated name. This is still
487 // deterministic: the only thing affecting that timestamp is the
488 // order of the files in the resultant archive.
489 //
490 // See also the functions that handle the lookup:
491 // in lldb: ObjectContainerBSDArchive::Archive::FindObject()
492 // in llvm/tools/dsymutil: BinaryHolder::GetArchiveMemberBuffers().
493 bool UniqueTimestamps = Deterministic && isDarwin(Kind);
4
Assuming 'Deterministic' is 0
494 std::map<StringRef, unsigned> FilenameCount;
495 if (UniqueTimestamps) {
5
Taking false branch
496 for (const NewArchiveMember &M : NewMembers)
497 FilenameCount[M.MemberName]++;
498 for (auto &Entry : FilenameCount)
499 Entry.second = Entry.second > 1 ? 1 : 0;
500 }
501
502 for (const NewArchiveMember &M : NewMembers) {
6
Assuming '__begin1' is not equal to '__end1'
503 std::string Header;
504 raw_string_ostream Out(Header);
505
506 MemoryBufferRef Buf = M.Buf->getMemBufferRef();
507 StringRef Data = Thin ? "" : Buf.getBuffer();
7
'?' condition is true
508
509 // ld64 expects the members to be 8-byte aligned for 64-bit content and at
510 // least 4-byte aligned for 32-bit content. Opt for the larger encoding
511 // uniformly. This matches the behaviour with cctools and ensures that ld64
512 // is happy with archives that we generate.
513 unsigned MemberPadding =
514 isDarwin(Kind) ? OffsetToAlignment(Data.size(), 8) : 0;
8
'?' condition is false
515 unsigned TailPadding = OffsetToAlignment(Data.size() + MemberPadding, 2);
516 StringRef Padding = StringRef(PaddingData, MemberPadding + TailPadding);
517
518 sys::TimePoint<std::chrono::seconds> ModTime;
519 if (UniqueTimestamps)
9
Taking false branch
520 // Increment timestamp for each file of a given name.
521 ModTime = sys::toTimePoint(FilenameCount[M.MemberName]++);
522 else
523 ModTime = M.ModTime;
524 printMemberHeader(Out, Pos, StringTable, MemberNames, Kind, Thin, ArcName,
525 M, ModTime, Buf.getBufferSize() + MemberPadding);
526 Out.flush();
527
528 Expected<std::vector<unsigned>> Symbols =
529 getSymbols(Buf, SymNames, HasObject);
10
Calling 'getSymbols'
530 if (auto E = Symbols.takeError())
531 return std::move(E);
532
533 Pos += Header.size() + Data.size() + Padding.size();
534 Ret.push_back({std::move(*Symbols), std::move(Header), Data, Padding});
535 }
536 // If there are no symbols, emit an empty symbol table, to satisfy Solaris
537 // tools, older versions of which expect a symbol table in a non-empty
538 // archive, regardless of whether there are any symbols in it.
539 if (HasObject && SymNames.tell() == 0)
540 SymNames << '\0' << '\0' << '\0';
541 return Ret;
542}
543
544Error llvm::writeArchive(StringRef ArcName,
545 ArrayRef<NewArchiveMember> NewMembers,
546 bool WriteSymtab, object::Archive::Kind Kind,
547 bool Deterministic, bool Thin,
548 std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
549 assert((!Thin || !isBSDLike(Kind)) && "Only the gnu format has a thin mode")(((!Thin || !isBSDLike(Kind)) && "Only the gnu format has a thin mode"
) ? static_cast<void> (0) : __assert_fail ("(!Thin || !isBSDLike(Kind)) && \"Only the gnu format has a thin mode\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Object/ArchiveWriter.cpp"
, 549, __PRETTY_FUNCTION__))
;
1
Assuming 'Thin' is not equal to 0
2
'?' condition is true
550
551 SmallString<0> SymNamesBuf;
552 raw_svector_ostream SymNames(SymNamesBuf);
553 SmallString<0> StringTableBuf;
554 raw_svector_ostream StringTable(StringTableBuf);
555
556 Expected<std::vector<MemberData>> DataOrErr = computeMemberData(
3
Calling 'computeMemberData'
557 StringTable, SymNames, Kind, Thin, ArcName, Deterministic, NewMembers);
558 if (Error E = DataOrErr.takeError())
559 return E;
560 std::vector<MemberData> &Data = *DataOrErr;
561
562 if (!StringTableBuf.empty())
563 Data.insert(Data.begin(), computeStringTable(StringTableBuf));
564
565 // We would like to detect if we need to switch to a 64-bit symbol table.
566 if (WriteSymtab) {
567 uint64_t MaxOffset = 0;
568 uint64_t LastOffset = MaxOffset;
569 for (const auto &M : Data) {
570 // Record the start of the member's offset
571 LastOffset = MaxOffset;
572 // Account for the size of each part associated with the member.
573 MaxOffset += M.Header.size() + M.Data.size() + M.Padding.size();
574 // We assume 32-bit symbols to see if 32-bit symbols are possible or not.
575 MaxOffset += M.Symbols.size() * 4;
576 }
577
578 // The SYM64 format is used when an archive's member offsets are larger than
579 // 32-bits can hold. The need for this shift in format is detected by
580 // writeArchive. To test this we need to generate a file with a member that
581 // has an offset larger than 32-bits but this demands a very slow test. To
582 // speed the test up we use this environment variable to pretend like the
583 // cutoff happens before 32-bits and instead happens at some much smaller
584 // value.
585 const char *Sym64Env = std::getenv("SYM64_THRESHOLD");
586 int Sym64Threshold = 32;
587 if (Sym64Env)
588 StringRef(Sym64Env).getAsInteger(10, Sym64Threshold);
589
590 // If LastOffset isn't going to fit in a 32-bit varible we need to switch
591 // to 64-bit. Note that the file can be larger than 4GB as long as the last
592 // member starts before the 4GB offset.
593 if (LastOffset >= (1ULL << Sym64Threshold)) {
594 if (Kind == object::Archive::K_DARWIN)
595 Kind = object::Archive::K_DARWIN64;
596 else
597 Kind = object::Archive::K_GNU64;
598 }
599 }
600
601 Expected<sys::fs::TempFile> Temp =
602 sys::fs::TempFile::create(ArcName + ".temp-archive-%%%%%%%.a");
603 if (!Temp)
604 return Temp.takeError();
605
606 raw_fd_ostream Out(Temp->FD, false);
607 if (Thin)
608 Out << "!<thin>\n";
609 else
610 Out << "!<arch>\n";
611
612 if (WriteSymtab)
613 writeSymbolTable(Out, Kind, Deterministic, Data, SymNamesBuf);
614
615 for (const MemberData &M : Data)
616 Out << M.Header << M.Data << M.Padding;
617
618 Out.flush();
619
620 // At this point, we no longer need whatever backing memory
621 // was used to generate the NewMembers. On Windows, this buffer
622 // could be a mapped view of the file we want to replace (if
623 // we're updating an existing archive, say). In that case, the
624 // rename would still succeed, but it would leave behind a
625 // temporary file (actually the original file renamed) because
626 // a file cannot be deleted while there's a handle open on it,
627 // only renamed. So by freeing this buffer, this ensures that
628 // the last open handle on the destination file, if any, is
629 // closed before we attempt to rename.
630 OldArchiveBuf.reset();
631
632 return Temp->keep(ArcName);
633}

/build/llvm-toolchain-snapshot-8~svn350071/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);
29
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~svn350071/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~svn350071/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)
21
Taking false branch
394 return E2;
395 if (!E2)
22
Taking false branch
396 return E1;
397 if (E1.isA<ErrorList>()) {
23
Assuming the condition is false
24
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>()) {
25
Assuming the condition is false
26
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>(
28
Calling constructor for 'Error'
415 new ErrorList(E1.takePayload(), E2.takePayload())));
27
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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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)
17
Taking false branch
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
18
Assuming the condition is true
19
Taking true branch
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
20
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)...));
16
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:983:35)>'
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 function is compatible with the helpers from Support/WithColor.h. You
957/// can pass any of them as the OS. Please consider using them instead of
958/// including 'error: ' in the ErrorBanner.
959///
960/// This is useful in the base level of your program to allow clean termination
961/// (allowing clean deallocation of resources, etc.), while reporting error
962/// information to the user.
963void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
964
965/// Write all error messages (if any) in E to a string. The newline character
966/// is used to separate error messages.
967inline std::string toString(Error E) {
968 SmallVector<std::string, 2> Errors;
969 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
970 Errors.push_back(EI.message());
971 });
972 return join(Errors.begin(), Errors.end(), "\n");
973}
974
975/// Consume a Error without doing anything. This method should be used
976/// only where an error can be considered a reasonable and expected return
977/// value.
978///
979/// Uses of this method are potentially indicative of design problems: If it's
980/// legitimate to do nothing while processing an "error", the error-producer
981/// might be more clearly refactored to return an Optional<T>.
982inline void consumeError(Error Err) {
983 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
15
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:983:35)>'
984}
985
986/// Helper for converting an Error to a bool.
987///
988/// This method returns true if Err is in an error state, or false if it is
989/// in a success state. Puts Err in a checked state in both cases (unlike
990/// Error::operator bool(), which only does this for success states).
991inline bool errorToBool(Error Err) {
992 bool IsError = static_cast<bool>(Err);
993 if (IsError)
994 consumeError(std::move(Err));
995 return IsError;
996}
997
998/// Helper for Errors used as out-parameters.
999///
1000/// This helper is for use with the Error-as-out-parameter idiom, where an error
1001/// is passed to a function or method by reference, rather than being returned.
1002/// In such cases it is helpful to set the checked bit on entry to the function
1003/// so that the error can be written to (unchecked Errors abort on assignment)
1004/// and clear the checked bit on exit so that clients cannot accidentally forget
1005/// to check the result. This helper performs these actions automatically using
1006/// RAII:
1007///
1008/// @code{.cpp}
1009/// Result foo(Error &Err) {
1010/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1011/// // <body of foo>
1012/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1013/// }
1014/// @endcode
1015///
1016/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1017/// used with optional Errors (Error pointers that are allowed to be null). If
1018/// ErrorAsOutParameter took an Error reference, an instance would have to be
1019/// created inside every condition that verified that Error was non-null. By
1020/// taking an Error pointer we can just create one instance at the top of the
1021/// function.
1022class ErrorAsOutParameter {
1023public:
1024 ErrorAsOutParameter(Error *Err) : Err(Err) {
1025 // Raise the checked bit if Err is success.
1026 if (Err)
1027 (void)!!*Err;
1028 }
1029
1030 ~ErrorAsOutParameter() {
1031 // Clear the checked bit.
1032 if (Err && !*Err)
1033 *Err = Error::success();
1034 }
1035
1036private:
1037 Error *Err;
1038};
1039
1040/// Helper for Expected<T>s used as out-parameters.
1041///
1042/// See ErrorAsOutParameter.
1043template <typename T>
1044class ExpectedAsOutParameter {
1045public:
1046 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1047 : ValOrErr(ValOrErr) {
1048 if (ValOrErr)
1049 (void)!!*ValOrErr;
1050 }
1051
1052 ~ExpectedAsOutParameter() {
1053 if (ValOrErr)
1054 ValOrErr->setUnchecked();
1055 }
1056
1057private:
1058 Expected<T> *ValOrErr;
1059};
1060
1061/// This class wraps a std::error_code in a Error.
1062///
1063/// This is useful if you're writing an interface that returns a Error
1064/// (or Expected) and you want to call code that still returns
1065/// std::error_codes.
1066class ECError : public ErrorInfo<ECError> {
1067 friend Error errorCodeToError(std::error_code);
1068
1069public:
1070 void setErrorCode(std::error_code EC) { this->EC = EC; }
1071 std::error_code convertToErrorCode() const override { return EC; }
1072 void log(raw_ostream &OS) const override { OS << EC.message(); }
1073
1074 // Used by ErrorInfo::classID.
1075 static char ID;
1076
1077protected:
1078 ECError() = default;
1079 ECError(std::error_code EC) : EC(EC) {}
1080
1081 std::error_code EC;
1082};
1083
1084/// The value returned by this function can be returned from convertToErrorCode
1085/// for Error values where no sensible translation to std::error_code exists.
1086/// It should only be used in this situation, and should never be used where a
1087/// sensible conversion to std::error_code is available, as attempts to convert
1088/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1089///error to try to convert such a value).
1090std::error_code inconvertibleErrorCode();
1091
1092/// Helper for converting an std::error_code to a Error.
1093Error errorCodeToError(std::error_code EC);
1094
1095/// Helper for converting an ECError to a std::error_code.
1096///
1097/// This method requires that Err be Error() or an ECError, otherwise it
1098/// will trigger a call to abort().
1099std::error_code errorToErrorCode(Error Err);
1100
1101/// Convert an ErrorOr<T> to an Expected<T>.
1102template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1103 if (auto EC = EO.getError())
1104 return errorCodeToError(EC);
1105 return std::move(*EO);
1106}
1107
1108/// Convert an Expected<T> to an ErrorOr<T>.
1109template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1110 if (auto Err = E.takeError())
1111 return errorToErrorCode(std::move(Err));
1112 return std::move(*E);
1113}
1114
1115/// This class wraps a string in an Error.
1116///
1117/// StringError is useful in cases where the client is not expected to be able
1118/// to consume the specific error message programmatically (for example, if the
1119/// error message is to be presented to the user).
1120///
1121/// StringError can also be used when additional information is to be printed
1122/// along with a error_code message. Depending on the constructor called, this
1123/// class can either display:
1124/// 1. the error_code message (ECError behavior)
1125/// 2. a string
1126/// 3. the error_code message and a string
1127///
1128/// These behaviors are useful when subtyping is required; for example, when a
1129/// specific library needs an explicit error type. In the example below,
1130/// PDBError is derived from StringError:
1131///
1132/// @code{.cpp}
1133/// Expected<int> foo() {
1134/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1135/// "Additional information");
1136/// }
1137/// @endcode
1138///
1139class StringError : public ErrorInfo<StringError> {
1140public:
1141 static char ID;
1142
1143 // Prints EC + S and converts to EC
1144 StringError(std::error_code EC, const Twine &S = Twine());
1145
1146 // Prints S and converts to EC
1147 StringError(const Twine &S, std::error_code EC);
1148
1149 void log(raw_ostream &OS) const override;
1150 std::error_code convertToErrorCode() const override;
1151
1152 const std::string &getMessage() const { return Msg; }
1153
1154private:
1155 std::string Msg;
1156 std::error_code EC;
1157 const bool PrintMsgOnly = false;
1158};
1159
1160/// Create formatted StringError object.
1161template <typename... Ts>
1162Error createStringError(std::error_code EC, char const *Fmt,
1163 const Ts &... Vals) {
1164 std::string Buffer;
1165 raw_string_ostream Stream(Buffer);
1166 Stream << format(Fmt, Vals...);
1167 return make_error<StringError>(Stream.str(), EC);
1168}
1169
1170Error createStringError(std::error_code EC, char const *Msg);
1171
1172/// This class wraps a filename and another Error.
1173///
1174/// In some cases, an error needs to live along a 'source' name, in order to
1175/// show more detailed information to the user.
1176class FileError final : public ErrorInfo<FileError> {
1177
1178 friend Error createFileError(std::string, Error);
1179
1180public:
1181 void log(raw_ostream &OS) const override {
1182 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~svn350071/include/llvm/Support/Error.h"
, 1182, __PRETTY_FUNCTION__))
;
1183 OS << "'" << FileName << "': ";
1184 Err->log(OS);
1185 }
1186
1187 Error takeError() { return Error(std::move(Err)); }
1188
1189 std::error_code convertToErrorCode() const override;
1190
1191 // Used by ErrorInfo::classID.
1192 static char ID;
1193
1194private:
1195 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1196 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~svn350071/include/llvm/Support/Error.h"
, 1196, __PRETTY_FUNCTION__))
;
1197 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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
1198 "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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
;
1199 FileName = F;
1200 Err = std::move(E);
1201 }
1202
1203 static Error build(std::string F, Error E) {
1204 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1205 }
1206
1207 std::string FileName;
1208 std::unique_ptr<ErrorInfoBase> Err;
1209};
1210
1211/// Concatenate a source file path and/or name with an Error. The resulting
1212/// Error is unchecked.
1213inline Error createFileError(std::string F, Error E) {
1214 return FileError::build(F, std::move(E));
1215}
1216
1217Error createFileError(std::string F, ErrorSuccess) = delete;
1218
1219/// Helper for check-and-exit error handling.
1220///
1221/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1222///
1223class ExitOnError {
1224public:
1225 /// Create an error on exit helper.
1226 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1227 : Banner(std::move(Banner)),
1228 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1229
1230 /// Set the banner string for any errors caught by operator().
1231 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1232
1233 /// Set the exit-code mapper function.
1234 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1235 this->GetExitCode = std::move(GetExitCode);
1236 }
1237
1238 /// Check Err. If it's in a failure state log the error(s) and exit.
1239 void operator()(Error Err) const { checkError(std::move(Err)); }
1240
1241 /// Check E. If it's in a success state then return the contained value. If
1242 /// it's in a failure state log the error(s) and exit.
1243 template <typename T> T operator()(Expected<T> &&E) const {
1244 checkError(E.takeError());
1245 return std::move(*E);
1246 }
1247
1248 /// Check E. If it's in a success state then return the contained reference. If
1249 /// it's in a failure state log the error(s) and exit.
1250 template <typename T> T& operator()(Expected<T&> &&E) const {
1251 checkError(E.takeError());
1252 return *E;
1253 }
1254
1255private:
1256 void checkError(Error Err) const {
1257 if (Err) {
1258 int ExitCode = GetExitCode(Err);
1259 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1260 exit(ExitCode);
1261 }
1262 }
1263
1264 std::string Banner;
1265 std::function<int(const Error &)> GetExitCode;
1266};
1267
1268/// Conversion from Error to LLVMErrorRef for C error bindings.
1269inline LLVMErrorRef wrap(Error Err) {
1270 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1271}
1272
1273/// Conversion from LLVMErrorRef to Error for C error bindings.
1274inline Error unwrap(LLVMErrorRef ErrRef) {
1275 return Error(std::unique_ptr<ErrorInfoBase>(
1276 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1277}
1278
1279} // end namespace llvm
1280
1281#endif // LLVM_SUPPORT_ERROR_H