Bug Summary

File:include/llvm/Support/Error.h
Warning:line 200, 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-9/lib/clang/9.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/lib/Object -I /build/llvm-toolchain-snapshot-9~svn362543/lib/Object -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/include -I /build/llvm-toolchain-snapshot-9~svn362543/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/9.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-9/lib/clang/9.0.0/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-9~svn362543/build-llvm/lib/Object -fdebug-prefix-map=/build/llvm-toolchain-snapshot-9~svn362543=. -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-2019-06-05-060531-1271-1 -x c++ /build/llvm-toolchain-snapshot-9~svn362543/lib/Object/ArchiveWriter.cpp -faddrsig

/build/llvm-toolchain-snapshot-9~svn362543/lib/Object/ArchiveWriter.cpp

→
1//===- ArchiveWriter.cpp - ar File Format implementation --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the writeArchive function.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/Object/ArchiveWriter.h"
14#include "llvm/ADT/ArrayRef.h"
15#include "llvm/ADT/StringRef.h"
16#include "llvm/BinaryFormat/Magic.h"
17#include "llvm/IR/LLVMContext.h"
18#include "llvm/Object/Archive.h"
19#include "llvm/Object/ObjectFile.h"
20#include "llvm/Object/SymbolicFile.h"
21#include "llvm/Support/EndianStream.h"
22#include "llvm/Support/Errc.h"
23#include "llvm/Support/ErrorHandling.h"
24#include "llvm/Support/Format.h"
25#include "llvm/Support/Path.h"
26#include "llvm/Support/ToolOutputFile.h"
27#include "llvm/Support/raw_ostream.h"
28
29#include <map>
30
31#if !defined(_MSC_VER) && !defined(__MINGW32__)
32#include <unistd.h>
33#else
34#include <io.h>
35#endif
36
37using namespace llvm;
38
39NewArchiveMember::NewArchiveMember(MemoryBufferRef BufRef)
40 : Buf(MemoryBuffer::getMemBuffer(BufRef, false)),
41 MemberName(BufRef.getBufferIdentifier()) {}
42
43Expected<NewArchiveMember>
44NewArchiveMember::getOldMember(const object::Archive::Child &OldMember,
45 bool Deterministic) {
46 Expected<llvm::MemoryBufferRef> BufOrErr = OldMember.getMemoryBufferRef();
47 if (!BufOrErr)
48 return BufOrErr.takeError();
49
50 NewArchiveMember M;
51 M.Buf = MemoryBuffer::getMemBuffer(*BufOrErr, false);
52 M.MemberName = M.Buf->getBufferIdentifier();
53 if (!Deterministic) {
54 auto ModTimeOrErr = OldMember.getLastModified();
55 if (!ModTimeOrErr)
56 return ModTimeOrErr.takeError();
57 M.ModTime = ModTimeOrErr.get();
58 Expected<unsigned> UIDOrErr = OldMember.getUID();
59 if (!UIDOrErr)
60 return UIDOrErr.takeError();
61 M.UID = UIDOrErr.get();
62 Expected<unsigned> GIDOrErr = OldMember.getGID();
63 if (!GIDOrErr)
64 return GIDOrErr.takeError();
65 M.GID = GIDOrErr.get();
66 Expected<sys::fs::perms> AccessModeOrErr = OldMember.getAccessMode();
67 if (!AccessModeOrErr)
68 return AccessModeOrErr.takeError();
69 M.Perms = AccessModeOrErr.get();
70 }
71 return std::move(M);
72}
73
74Expected<NewArchiveMember> NewArchiveMember::getFile(StringRef FileName,
75 bool Deterministic) {
76 sys::fs::file_status Status;
77 int FD;
78 if (auto EC = sys::fs::openFileForRead(FileName, FD))
79 return errorCodeToError(EC);
80 assert(FD != -1)((FD != -1) ? static_cast<void> (0) : __assert_fail ("FD != -1"
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Object/ArchiveWriter.cpp"
, 80, __PRETTY_FUNCTION__));
81
82 if (auto EC = sys::fs::status(FD, Status))
83 return errorCodeToError(EC);
84
85 // Opening a directory doesn't make sense. Let it fail.
86 // Linux cannot open directories with open(2), although
87 // cygwin and *bsd can.
88 if (Status.type() == sys::fs::file_type::directory_file)
89 return errorCodeToError(make_error_code(errc::is_a_directory));
90
91 ErrorOr<std::unique_ptr<MemoryBuffer>> MemberBufferOrErr =
92 MemoryBuffer::getOpenFile(FD, FileName, Status.getSize(), false);
93 if (!MemberBufferOrErr)
94 return errorCodeToError(MemberBufferOrErr.getError());
95
96 if (close(FD) != 0)
97 return errorCodeToError(std::error_code(errno(*__errno_location ()), std::generic_category()));
98
99 NewArchiveMember M;
100 M.Buf = std::move(*MemberBufferOrErr);
101 M.MemberName = M.Buf->getBufferIdentifier();
102 if (!Deterministic) {
103 M.ModTime = std::chrono::time_point_cast<std::chrono::seconds>(
104 Status.getLastModificationTime());
105 M.UID = Status.getUser();
106 M.GID = Status.getGroup();
107 M.Perms = Status.permissions();
108 }
109 return std::move(M);
110}
111
112template <typename T>
113static void printWithSpacePadding(raw_ostream &OS, T Data, unsigned Size) {
114 uint64_t OldPos = OS.tell();
115 OS << Data;
116 unsigned SizeSoFar = OS.tell() - OldPos;
117 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-9~svn362543/lib/Object/ArchiveWriter.cpp"
, 117, __PRETTY_FUNCTION__));
118 OS.indent(Size - SizeSoFar);
119}
120
121static bool isDarwin(object::Archive::Kind Kind) {
122 return Kind == object::Archive::K_DARWIN ||
123 Kind == object::Archive::K_DARWIN64;
124}
125
126static bool isBSDLike(object::Archive::Kind Kind) {
127 switch (Kind) {
128 case object::Archive::K_GNU:
129 case object::Archive::K_GNU64:
130 return false;
131 case object::Archive::K_BSD:
132 case object::Archive::K_DARWIN:
133 case object::Archive::K_DARWIN64:
134 return true;
135 case object::Archive::K_COFF:
136 break;
137 }
138 llvm_unreachable("not supported for writting")::llvm::llvm_unreachable_internal("not supported for writting"
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Object/ArchiveWriter.cpp"
, 138);
139}
140
141template <class T>
142static void print(raw_ostream &Out, object::Archive::Kind Kind, T Val) {
143 support::endian::write(Out, Val,
144 isBSDLike(Kind) ? support::little : support::big);
145}
146
147static void printRestOfMemberHeader(
148 raw_ostream &Out, const sys::TimePoint<std::chrono::seconds> &ModTime,
149 unsigned UID, unsigned GID, unsigned Perms, unsigned Size) {
150 printWithSpacePadding(Out, sys::toTimeT(ModTime), 12);
151
152 // The format has only 6 chars for uid and gid. Truncate if the provided
153 // values don't fit.
154 printWithSpacePadding(Out, UID % 1000000, 6);
155 printWithSpacePadding(Out, GID % 1000000, 6);
156
157 printWithSpacePadding(Out, format("%o", Perms), 8);
158 printWithSpacePadding(Out, Size, 10);
159 Out << "`\n";
160}
161
162static void
163printGNUSmallMemberHeader(raw_ostream &Out, StringRef Name,
164 const sys::TimePoint<std::chrono::seconds> &ModTime,
165 unsigned UID, unsigned GID, unsigned Perms,
166 unsigned Size) {
167 printWithSpacePadding(Out, Twine(Name) + "/", 16);
168 printRestOfMemberHeader(Out, ModTime, UID, GID, Perms, Size);
169}
170
171static void
172printBSDMemberHeader(raw_ostream &Out, uint64_t Pos, StringRef Name,
173 const sys::TimePoint<std::chrono::seconds> &ModTime,
174 unsigned UID, unsigned GID, unsigned Perms,
175 unsigned Size) {
176 uint64_t PosAfterHeader = Pos + 60 + Name.size();
177 // Pad so that even 64 bit object files are aligned.
178 unsigned Pad = OffsetToAlignment(PosAfterHeader, 8);
179 unsigned NameWithPadding = Name.size() + Pad;
180 printWithSpacePadding(Out, Twine("#1/") + Twine(NameWithPadding), 16);
181 printRestOfMemberHeader(Out, ModTime, UID, GID, Perms,
182 NameWithPadding + Size);
183 Out << Name;
184 while (Pad--)
185 Out.write(uint8_t(0));
186}
187
188static bool useStringTable(bool Thin, StringRef Name) {
189 return Thin || Name.size() >= 16 || Name.contains('/');
190}
191
192static bool is64BitKind(object::Archive::Kind Kind) {
193 switch (Kind) {
194 case object::Archive::K_GNU:
195 case object::Archive::K_BSD:
196 case object::Archive::K_DARWIN:
197 case object::Archive::K_COFF:
198 return false;
199 case object::Archive::K_DARWIN64:
200 case object::Archive::K_GNU64:
201 return true;
202 }
203 llvm_unreachable("not supported for writting")::llvm::llvm_unreachable_internal("not supported for writting"
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Object/ArchiveWriter.cpp"
, 203);
204}
205
206static void
207printMemberHeader(raw_ostream &Out, uint64_t Pos, raw_ostream &StringTable,
208 StringMap<uint64_t> &MemberNames, object::Archive::Kind Kind,
209 bool Thin, const NewArchiveMember &M,
210 sys::TimePoint<std::chrono::seconds> ModTime, unsigned Size) {
211 if (isBSDLike(Kind))
212 return printBSDMemberHeader(Out, Pos, M.MemberName, ModTime, M.UID, M.GID,
213 M.Perms, Size);
214 if (!useStringTable(Thin, M.MemberName))
215 return printGNUSmallMemberHeader(Out, M.MemberName, ModTime, M.UID, M.GID,
216 M.Perms, Size);
217 Out << '/';
218 uint64_t NamePos;
219 if (Thin) {
220 NamePos = StringTable.tell();
221 StringTable << M.MemberName << "/\n";
222 } else {
223 auto Insertion = MemberNames.insert({M.MemberName, uint64_t(0)});
224 if (Insertion.second) {
225 Insertion.first->second = StringTable.tell();
226 StringTable << M.MemberName << "/\n";
227 }
228 NamePos = Insertion.first->second;
229 }
230 printWithSpacePadding(Out, NamePos, 15);
231 printRestOfMemberHeader(Out, ModTime, M.UID, M.GID, M.Perms, Size);
232}
233
234namespace {
235struct MemberData {
236 std::vector<unsigned> Symbols;
237 std::string Header;
238 StringRef Data;
239 StringRef Padding;
240};
241} // namespace
242
243static MemberData computeStringTable(StringRef Names) {
244 unsigned Size = Names.size();
245 unsigned Pad = OffsetToAlignment(Size, 2);
246 std::string Header;
247 raw_string_ostream Out(Header);
248 printWithSpacePadding(Out, "//", 48);
249 printWithSpacePadding(Out, Size + Pad, 10);
250 Out << "`\n";
251 Out.flush();
252 return {{}, std::move(Header), Names, Pad ? "\n" : ""};
253}
254
255static sys::TimePoint<std::chrono::seconds> now(bool Deterministic) {
256 using namespace std::chrono;
257
258 if (!Deterministic)
259 return time_point_cast<seconds>(system_clock::now());
260 return sys::TimePoint<seconds>();
261}
262
263static bool isArchiveSymbol(const object::BasicSymbolRef &S) {
264 uint32_t Symflags = S.getFlags();
265 if (Symflags & object::SymbolRef::SF_FormatSpecific)
266 return false;
267 if (!(Symflags & object::SymbolRef::SF_Global))
268 return false;
269 if (Symflags & object::SymbolRef::SF_Undefined)
270 return false;
271 return true;
272}
273
274static void printNBits(raw_ostream &Out, object::Archive::Kind Kind,
275 uint64_t Val) {
276 if (is64BitKind(Kind))
277 print<uint64_t>(Out, Kind, Val);
278 else
279 print<uint32_t>(Out, Kind, Val);
280}
281
282static void writeSymbolTable(raw_ostream &Out, object::Archive::Kind Kind,
283 bool Deterministic, ArrayRef<MemberData> Members,
284 StringRef StringTable) {
285 // We don't write a symbol table on an archive with no members -- except on
286 // Darwin, where the linker will abort unless the archive has a symbol table.
287 if (StringTable.empty() && !isDarwin(Kind))
288 return;
289
290 unsigned NumSyms = 0;
291 for (const MemberData &M : Members)
292 NumSyms += M.Symbols.size();
293
294 unsigned Size = 0;
295 unsigned OffsetSize = is64BitKind(Kind) ? sizeof(uint64_t) : sizeof(uint32_t);
296
297 Size += OffsetSize; // Number of entries
298 if (isBSDLike(Kind))
299 Size += NumSyms * OffsetSize * 2; // Table
300 else
301 Size += NumSyms * OffsetSize; // Table
302 if (isBSDLike(Kind))
303 Size += OffsetSize; // byte count
304 Size += StringTable.size();
305 // ld64 expects the members to be 8-byte aligned for 64-bit content and at
306 // least 4-byte aligned for 32-bit content. Opt for the larger encoding
307 // uniformly.
308 // We do this for all bsd formats because it simplifies aligning members.
309 unsigned Alignment = isBSDLike(Kind) ? 8 : 2;
310 unsigned Pad = OffsetToAlignment(Size, Alignment);
311 Size += Pad;
312
313 if (isBSDLike(Kind)) {
314 const char *Name = is64BitKind(Kind) ? "__.SYMDEF_64" : "__.SYMDEF";
315 printBSDMemberHeader(Out, Out.tell(), Name, now(Deterministic), 0, 0, 0,
316 Size);
317 } else {
318 const char *Name = is64BitKind(Kind) ? "/SYM64" : "";
319 printGNUSmallMemberHeader(Out, Name, now(Deterministic), 0, 0, 0, Size);
320 }
321
322 uint64_t Pos = Out.tell() + Size;
323
324 if (isBSDLike(Kind))
325 printNBits(Out, Kind, NumSyms * 2 * OffsetSize);
326 else
327 printNBits(Out, Kind, NumSyms);
328
329 for (const MemberData &M : Members) {
330 for (unsigned StringOffset : M.Symbols) {
331 if (isBSDLike(Kind))
332 printNBits(Out, Kind, StringOffset);
333 printNBits(Out, Kind, Pos); // member offset
334 }
335 Pos += M.Header.size() + M.Data.size() + M.Padding.size();
336 }
337
338 if (isBSDLike(Kind))
339 // byte count of the string table
340 printNBits(Out, Kind, StringTable.size());
341 Out << StringTable;
342
343 while (Pad--)
344 Out.write(uint8_t(0));
345}
346
347static Expected<std::vector<unsigned>>
348getSymbols(MemoryBufferRef Buf, raw_ostream &SymNames, bool &HasObject) {
349 std::vector<unsigned> Ret;
350
351 // In the scenario when LLVMContext is populated SymbolicFile will contain a
352 // reference to it, thus SymbolicFile should be destroyed first.
353 LLVMContext Context;
354 std::unique_ptr<object::SymbolicFile> Obj;
355 if (identify_magic(Buf.getBuffer()) == file_magic::bitcode) {
11
←
Assuming the condition is true
→
12
←
Taking true branch
→
356 auto ObjOrErr = object::SymbolicFile::createSymbolicFile(
357 Buf, file_magic::bitcode, &Context);
358 if (!ObjOrErr) {
13
←
Taking true branch
→
359 // FIXME: check only for "not an object file" errors.
360 consumeError(ObjOrErr.takeError());
14
←
Calling 'consumeError'
→
361 return Ret;
362 }
363 Obj = std::move(*ObjOrErr);
364 } else {
365 auto ObjOrErr = object::SymbolicFile::createSymbolicFile(Buf);
366 if (!ObjOrErr) {
367 // FIXME: check only for "not an object file" errors.
368 consumeError(ObjOrErr.takeError());
369 return Ret;
370 }
371 Obj = std::move(*ObjOrErr);
372 }
373
374 HasObject = true;
375 for (const object::BasicSymbolRef &S : Obj->symbols()) {
376 if (!isArchiveSymbol(S))
377 continue;
378 Ret.push_back(SymNames.tell());
379 if (Error E = S.printName(SymNames))
380 return std::move(E);
381 SymNames << '\0';
382 }
383 return Ret;
384}
385
386static Expected<std::vector<MemberData>>
387computeMemberData(raw_ostream &StringTable, raw_ostream &SymNames,
388 object::Archive::Kind Kind, bool Thin, bool Deterministic,
389 ArrayRef<NewArchiveMember> NewMembers) {
390 static char PaddingData[8] = {'\n', '\n', '\n', '\n', '\n', '\n', '\n', '\n'};
391
392 // This ignores the symbol table, but we only need the value mod 8 and the
393 // symbol table is aligned to be a multiple of 8 bytes
394 uint64_t Pos = 0;
395
396 std::vector<MemberData> Ret;
397 bool HasObject = false;
398
399 // Deduplicate long member names in the string table and reuse earlier name
400 // offsets. This especially saves space for COFF Import libraries where all
401 // members have the same name.
402 StringMap<uint64_t> MemberNames;
403
404 // UniqueTimestamps is a special case to improve debugging on Darwin:
405 //
406 // The Darwin linker does not link debug info into the final
407 // binary. Instead, it emits entries of type N_OSO in in the output
408 // binary's symbol table, containing references to the linked-in
409 // object files. Using that reference, the debugger can read the
410 // debug data directly from the object files. Alternatively, an
411 // invocation of 'dsymutil' will link the debug data from the object
412 // files into a dSYM bundle, which can be loaded by the debugger,
413 // instead of the object files.
414 //
415 // For an object file, the N_OSO entries contain the absolute path
416 // path to the file, and the file's timestamp. For an object
417 // included in an archive, the path is formatted like
418 // "/absolute/path/to/archive.a(member.o)", and the timestamp is the
419 // archive member's timestamp, rather than the archive's timestamp.
420 //
421 // However, this doesn't always uniquely identify an object within
422 // an archive -- an archive file can have multiple entries with the
423 // same filename. (This will happen commonly if the original object
424 // files started in different directories.) The only way they get
425 // distinguished, then, is via the timestamp. But this process is
426 // unable to find the correct object file in the archive when there
427 // are two files of the same name and timestamp.
428 //
429 // Additionally, timestamp==0 is treated specially, and causes the
430 // timestamp to be ignored as a match criteria.
431 //
432 // That will "usually" work out okay when creating an archive not in
433 // deterministic timestamp mode, because the objects will probably
434 // have been created at different timestamps.
435 //
436 // To ameliorate this problem, in deterministic archive mode (which
437 // is the default), on Darwin we will emit a unique non-zero
438 // timestamp for each entry with a duplicated name. This is still
439 // deterministic: the only thing affecting that timestamp is the
440 // order of the files in the resultant archive.
441 //
442 // See also the functions that handle the lookup:
443 // in lldb: ObjectContainerBSDArchive::Archive::FindObject()
444 // in llvm/tools/dsymutil: BinaryHolder::GetArchiveMemberBuffers().
445 bool UniqueTimestamps = Deterministic && isDarwin(Kind);
4
←
Assuming 'Deterministic' is 0
→
446 std::map<StringRef, unsigned> FilenameCount;
447 if (UniqueTimestamps) {
5
←
Taking false branch
→
448 for (const NewArchiveMember &M : NewMembers)
449 FilenameCount[M.MemberName]++;
450 for (auto &Entry : FilenameCount)
451 Entry.second = Entry.second > 1 ? 1 : 0;
452 }
453
454 for (const NewArchiveMember &M : NewMembers) {
6
←
Assuming '__begin1' is not equal to '__end1'
→
455 std::string Header;
456 raw_string_ostream Out(Header);
457
458 MemoryBufferRef Buf = M.Buf->getMemBufferRef();
459 StringRef Data = Thin ? "" : Buf.getBuffer();
7
←
'?' condition is true
→
460
461 // ld64 expects the members to be 8-byte aligned for 64-bit content and at
462 // least 4-byte aligned for 32-bit content. Opt for the larger encoding
463 // uniformly. This matches the behaviour with cctools and ensures that ld64
464 // is happy with archives that we generate.
465 unsigned MemberPadding =
466 isDarwin(Kind) ? OffsetToAlignment(Data.size(), 8) : 0;
8
←
'?' condition is false
→
467 unsigned TailPadding = OffsetToAlignment(Data.size() + MemberPadding, 2);
468 StringRef Padding = StringRef(PaddingData, MemberPadding + TailPadding);
469
470 sys::TimePoint<std::chrono::seconds> ModTime;
471 if (UniqueTimestamps)
9
←
Taking false branch
→
472 // Increment timestamp for each file of a given name.
473 ModTime = sys::toTimePoint(FilenameCount[M.MemberName]++);
474 else
475 ModTime = M.ModTime;
476 printMemberHeader(Out, Pos, StringTable, MemberNames, Kind, Thin, M,
477 ModTime, Buf.getBufferSize() + MemberPadding);
478 Out.flush();
479
480 Expected<std::vector<unsigned>> Symbols =
481 getSymbols(Buf, SymNames, HasObject);
10
←
Calling 'getSymbols'
→
482 if (auto E = Symbols.takeError())
483 return std::move(E);
484
485 Pos += Header.size() + Data.size() + Padding.size();
486 Ret.push_back({std::move(*Symbols), std::move(Header), Data, Padding});
487 }
488 // If there are no symbols, emit an empty symbol table, to satisfy Solaris
489 // tools, older versions of which expect a symbol table in a non-empty
490 // archive, regardless of whether there are any symbols in it.
491 if (HasObject && SymNames.tell() == 0)
492 SymNames << '\0' << '\0' << '\0';
493 return Ret;
494}
495
496namespace llvm {
497
498static ErrorOr<SmallString<128>> canonicalizePath(StringRef P) {
499 SmallString<128> Ret = P;
500 std::error_code Err = sys::fs::make_absolute(Ret);
501 if (Err)
502 return Err;
503 sys::path::remove_dots(Ret, /*removedotdot*/ true);
504 return Ret;
505}
506
507// Compute the relative path from From to To.
508Expected<std::string> computeArchiveRelativePath(StringRef From, StringRef To) {
509 ErrorOr<SmallString<128>> PathToOrErr = canonicalizePath(To);
510 ErrorOr<SmallString<128>> DirFromOrErr = canonicalizePath(From);
511 if (!PathToOrErr || !DirFromOrErr)
512 return errorCodeToError(std::error_code(errno(*__errno_location ()), std::generic_category()));
513
514 const SmallString<128> &PathTo = *PathToOrErr;
515 const SmallString<128> &DirFrom = sys::path::parent_path(*DirFromOrErr);
516
517 // Can't construct a relative path between different roots
518 if (sys::path::root_name(PathTo) != sys::path::root_name(DirFrom))
519 return sys::path::convert_to_slash(PathTo);
520
521 // Skip common prefixes
522 auto FromTo =
523 std::mismatch(sys::path::begin(DirFrom), sys::path::end(DirFrom),
524 sys::path::begin(PathTo));
525 auto FromI = FromTo.first;
526 auto ToI = FromTo.second;
527
528 // Construct relative path
529 SmallString<128> Relative;
530 for (auto FromE = sys::path::end(DirFrom); FromI != FromE; ++FromI)
531 sys::path::append(Relative, sys::path::Style::posix, "..");
532
533 for (auto ToE = sys::path::end(PathTo); ToI != ToE; ++ToI)
534 sys::path::append(Relative, sys::path::Style::posix, *ToI);
535
536 return Relative.str();
537}
538
539Error writeArchive(StringRef ArcName, ArrayRef<NewArchiveMember> NewMembers,
540 bool WriteSymtab, object::Archive::Kind Kind,
541 bool Deterministic, bool Thin,
542 std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
543 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-9~svn362543/lib/Object/ArchiveWriter.cpp"
, 543, __PRETTY_FUNCTION__));
1
Assuming 'Thin' is not equal to 0
→
2
←
'?' condition is true
→
544
545 SmallString<0> SymNamesBuf;
546 raw_svector_ostream SymNames(SymNamesBuf);
547 SmallString<0> StringTableBuf;
548 raw_svector_ostream StringTable(StringTableBuf);
549
550 Expected<std::vector<MemberData>> DataOrErr = computeMemberData(
3
←
Calling 'computeMemberData'
→
551 StringTable, SymNames, Kind, Thin, Deterministic, NewMembers);
552 if (Error E = DataOrErr.takeError())
553 return E;
554 std::vector<MemberData> &Data = *DataOrErr;
555
556 if (!StringTableBuf.empty())
557 Data.insert(Data.begin(), computeStringTable(StringTableBuf));
558
559 // We would like to detect if we need to switch to a 64-bit symbol table.
560 if (WriteSymtab) {
561 uint64_t MaxOffset = 0;
562 uint64_t LastOffset = MaxOffset;
563 for (const auto &M : Data) {
564 // Record the start of the member's offset
565 LastOffset = MaxOffset;
566 // Account for the size of each part associated with the member.
567 MaxOffset += M.Header.size() + M.Data.size() + M.Padding.size();
568 // We assume 32-bit symbols to see if 32-bit symbols are possible or not.
569 MaxOffset += M.Symbols.size() * 4;
570 }
571
572 // The SYM64 format is used when an archive's member offsets are larger than
573 // 32-bits can hold. The need for this shift in format is detected by
574 // writeArchive. To test this we need to generate a file with a member that
575 // has an offset larger than 32-bits but this demands a very slow test. To
576 // speed the test up we use this environment variable to pretend like the
577 // cutoff happens before 32-bits and instead happens at some much smaller
578 // value.
579 const char *Sym64Env = std::getenv("SYM64_THRESHOLD");
580 int Sym64Threshold = 32;
581 if (Sym64Env)
582 StringRef(Sym64Env).getAsInteger(10, Sym64Threshold);
583
584 // If LastOffset isn't going to fit in a 32-bit varible we need to switch
585 // to 64-bit. Note that the file can be larger than 4GB as long as the last
586 // member starts before the 4GB offset.
587 if (LastOffset >= (1ULL << Sym64Threshold)) {
588 if (Kind == object::Archive::K_DARWIN)
589 Kind = object::Archive::K_DARWIN64;
590 else
591 Kind = object::Archive::K_GNU64;
592 }
593 }
594
595 Expected<sys::fs::TempFile> Temp =
596 sys::fs::TempFile::create(ArcName + ".temp-archive-%%%%%%%.a");
597 if (!Temp)
598 return Temp.takeError();
599
600 raw_fd_ostream Out(Temp->FD, false);
601 if (Thin)
602 Out << "!<thin>\n";
603 else
604 Out << "!<arch>\n";
605
606 if (WriteSymtab)
607 writeSymbolTable(Out, Kind, Deterministic, Data, SymNamesBuf);
608
609 for (const MemberData &M : Data)
610 Out << M.Header << M.Data << M.Padding;
611
612 Out.flush();
613
614 // At this point, we no longer need whatever backing memory
615 // was used to generate the NewMembers. On Windows, this buffer
616 // could be a mapped view of the file we want to replace (if
617 // we're updating an existing archive, say). In that case, the
618 // rename would still succeed, but it would leave behind a
619 // temporary file (actually the original file renamed) because
620 // a file cannot be deleted while there's a handle open on it,
621 // only renamed. So by freeing this buffer, this ensures that
622 // the last open handle on the destination file, if any, is
623 // closed before we attempt to rename.
624 OldArchiveBuf.reset();
625
626 return Temp->keep(ArcName);
627}
628
629} // namespace llvm
←

/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15
16#include "llvm-c/Error.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Config/abi-breaking.h"
22#include "llvm/Support/AlignOf.h"
23#include "llvm/Support/Compiler.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/ErrorHandling.h"
26#include "llvm/Support/ErrorOr.h"
27#include "llvm/Support/Format.h"
28#include "llvm/Support/raw_ostream.h"
29#include <algorithm>
30#include <cassert>
31#include <cstdint>
32#include <cstdlib>
33#include <functional>
34#include <memory>
35#include <new>
36#include <string>
37#include <system_error>
38#include <type_traits>
39#include <utility>
40#include <vector>
41
42namespace llvm {
43
44class ErrorSuccess;
45
46/// Base class for error info classes. Do not extend this directly: Extend
47/// the ErrorInfo template subclass instead.
48class ErrorInfoBase {
49public:
50 virtual ~ErrorInfoBase() = default;
51
52 /// Print an error message to an output stream.
53 virtual void log(raw_ostream &OS) const = 0;
54
55 /// Return the error message as a string.
56 virtual std::string message() const {
57 std::string Msg;
58 raw_string_ostream OS(Msg);
59 log(OS);
60 return OS.str();
61 }
62
63 /// Convert this error to a std::error_code.
64 ///
65 /// This is a temporary crutch to enable interaction with code still
66 /// using std::error_code. It will be removed in the future.
67 virtual std::error_code convertToErrorCode() const = 0;
68
69 // Returns the class ID for this type.
70 static const void *classID() { return &ID; }
71
72 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
73 virtual const void *dynamicClassID() const = 0;
74
75 // Check whether this instance is a subclass of the class identified by
76 // ClassID.
77 virtual bool isA(const void *const ClassID) const {
78 return ClassID == classID();
79 }
80
81 // Check whether this instance is a subclass of ErrorInfoT.
82 template <typename ErrorInfoT> bool isA() const {
83 return isA(ErrorInfoT::classID());
84 }
85
86private:
87 virtual void anchor();
88
89 static char ID;
90};
91
92/// Lightweight error class with error context and mandatory checking.
93///
94/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
95/// are represented by setting the pointer to a ErrorInfoBase subclass
96/// instance containing information describing the failure. Success is
97/// represented by a null pointer value.
98///
99/// Instances of Error also contains a 'Checked' flag, which must be set
100/// before the destructor is called, otherwise the destructor will trigger a
101/// runtime error. This enforces at runtime the requirement that all Error
102/// instances be checked or returned to the caller.
103///
104/// There are two ways to set the checked flag, depending on what state the
105/// Error instance is in. For Error instances indicating success, it
106/// is sufficient to invoke the boolean conversion operator. E.g.:
107///
108/// @code{.cpp}
109/// Error foo(<...>);
110///
111/// if (auto E = foo(<...>))
112/// return E; // <- Return E if it is in the error state.
113/// // We have verified that E was in the success state. It can now be safely
114/// // destroyed.
115/// @endcode
116///
117/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
118/// without testing the return value will raise a runtime error, even if foo
119/// returns success.
120///
121/// For Error instances representing failure, you must use either the
122/// handleErrors or handleAllErrors function with a typed handler. E.g.:
123///
124/// @code{.cpp}
125/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
126/// // Custom error info.
127/// };
128///
129/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
130///
131/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
132/// auto NewE =
133/// handleErrors(E,
134/// [](const MyErrorInfo &M) {
135/// // Deal with the error.
136/// },
137/// [](std::unique_ptr<OtherError> M) -> Error {
138/// if (canHandle(*M)) {
139/// // handle error.
140/// return Error::success();
141/// }
142/// // Couldn't handle this error instance. Pass it up the stack.
143/// return Error(std::move(M));
144/// );
145/// // Note - we must check or return NewE in case any of the handlers
146/// // returned a new error.
147/// @endcode
148///
149/// The handleAllErrors function is identical to handleErrors, except
150/// that it has a void return type, and requires all errors to be handled and
151/// no new errors be returned. It prevents errors (assuming they can all be
152/// handled) from having to be bubbled all the way to the top-level.
153///
154/// *All* Error instances must be checked before destruction, even if
155/// they're moved-assigned or constructed from Success values that have already
156/// been checked. This enforces checking through all levels of the call stack.
157class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
158 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
159 // pointers out of this class to add to the error list.
160 friend class ErrorList;
161 friend class FileError;
162
163 // handleErrors needs to be able to set the Checked flag.
164 template <typename... HandlerTs>
165 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
166
167 // Expected<T> needs to be able to steal the payload when constructed from an
168 // error.
169 template <typename T> friend class Expected;
170
171 // wrap needs to be able to steal the payload.
172 friend LLVMErrorRef wrap(Error);
173
174protected:
175 /// Create a success value. Prefer using 'Error::success()' for readability
176 Error() {
177 setPtr(nullptr);
178 setChecked(false);
179 }
180
181public:
182 /// Create a success value.
183 static ErrorSuccess success();
184
185 // Errors are not copy-constructable.
186 Error(const Error &Other) = delete;
187
188 /// Move-construct an error value. The newly constructed error is considered
189 /// unchecked, even if the source error had been checked. The original error
190 /// becomes a checked Success value, regardless of its original state.
191 Error(Error &&Other) {
192 setChecked(true);
193 *this = std::move(Other);
194 }
195
196 /// Create an error value. Prefer using the 'make_error' function, but
197 /// this constructor can be useful when "re-throwing" errors from handlers.
198 Error(std::unique_ptr<ErrorInfoBase> Payload) {
199 setPtr(Payload.release());
200 setChecked(false);
32
←
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
201 }
202
203 // Errors are not copy-assignable.
204 Error &operator=(const Error &Other) = delete;
205
206 /// Move-assign an error value. The current error must represent success, you
207 /// you cannot overwrite an unhandled error. The current error is then
208 /// considered unchecked. The source error becomes a checked success value,
209 /// regardless of its original state.
210 Error &operator=(Error &&Other) {
211 // Don't allow overwriting of unchecked values.
212 assertIsChecked();
213 setPtr(Other.getPtr());
214
215 // This Error is unchecked, even if the source error was checked.
216 setChecked(false);
217
218 // Null out Other's payload and set its checked bit.
219 Other.setPtr(nullptr);
220 Other.setChecked(true);
221
222 return *this;
223 }
224
225 /// Destroy a Error. Fails with a call to abort() if the error is
226 /// unchecked.
227 ~Error() {
228 assertIsChecked();
229 delete getPtr();
230 }
231
232 /// Bool conversion. Returns true if this Error is in a failure state,
233 /// and false if it is in an accept state. If the error is in a Success state
234 /// it will be considered checked.
235 explicit operator bool() {
236 setChecked(getPtr() == nullptr);
237 return getPtr() != nullptr;
238 }
239
240 /// Check whether one error is a subclass of another.
241 template <typename ErrT> bool isA() const {
242 return getPtr() && getPtr()->isA(ErrT::classID());
243 }
244
245 /// Returns the dynamic class id of this error, or null if this is a success
246 /// value.
247 const void* dynamicClassID() const {
248 if (!getPtr())
249 return nullptr;
250 return getPtr()->dynamicClassID();
251 }
252
253private:
254#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
255 // assertIsChecked() happens very frequently, but under normal circumstances
256 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
257 // of debug prints can cause the function to be too large for inlining. So
258 // it's important that we define this function out of line so that it can't be
259 // inlined.
260 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
261 void fatalUncheckedError() const;
262#endif
263
264 void assertIsChecked() {
265#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
266 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
267 fatalUncheckedError();
268#endif
269 }
270
271 ErrorInfoBase *getPtr() const {
272 return reinterpret_cast<ErrorInfoBase*>(
273 reinterpret_cast<uintptr_t>(Payload) &
274 ~static_cast<uintptr_t>(0x1));
275 }
276
277 void setPtr(ErrorInfoBase *EI) {
278#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
279 Payload = reinterpret_cast<ErrorInfoBase*>(
280 (reinterpret_cast<uintptr_t>(EI) &
281 ~static_cast<uintptr_t>(0x1)) |
282 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
283#else
284 Payload = EI;
285#endif
286 }
287
288 bool getChecked() const {
289#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
290 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
291#else
292 return true;
293#endif
294 }
295
296 void setChecked(bool V) {
297 Payload = reinterpret_cast<ErrorInfoBase*>(
298 (reinterpret_cast<uintptr_t>(Payload) &
299 ~static_cast<uintptr_t>(0x1)) |
300 (V ? 0 : 1));
301 }
302
303 std::unique_ptr<ErrorInfoBase> takePayload() {
304 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
305 setPtr(nullptr);
306 setChecked(true);
307 return Tmp;
308 }
309
310 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
311 if (auto P = E.getPtr())
312 P->log(OS);
313 else
314 OS << "success";
315 return OS;
316 }
317
318 ErrorInfoBase *Payload = nullptr;
319};
320
321/// Subclass of Error for the sole purpose of identifying the success path in
322/// the type system. This allows to catch invalid conversion to Expected<T> at
323/// compile time.
324class ErrorSuccess final : public Error {};
325
326inline ErrorSuccess Error::success() { return ErrorSuccess(); }
327
328/// Make a Error instance representing failure using the given error info
329/// type.
330template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
331 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
332}
333
334/// Base class for user error types. Users should declare their error types
335/// like:
336///
337/// class MyError : public ErrorInfo<MyError> {
338/// ....
339/// };
340///
341/// This class provides an implementation of the ErrorInfoBase::kind
342/// method, which is used by the Error RTTI system.
343template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
344class ErrorInfo : public ParentErrT {
345public:
346 using ParentErrT::ParentErrT; // inherit constructors
347
348 static const void *classID() { return &ThisErrT::ID; }
349
350 const void *dynamicClassID() const override { return &ThisErrT::ID; }
351
352 bool isA(const void *const ClassID) const override {
353 return ClassID == classID() || ParentErrT::isA(ClassID);
354 }
355};
356
357/// Special ErrorInfo subclass representing a list of ErrorInfos.
358/// Instances of this class are constructed by joinError.
359class ErrorList final : public ErrorInfo<ErrorList> {
360 // handleErrors needs to be able to iterate the payload list of an
361 // ErrorList.
362 template <typename... HandlerTs>
363 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
364
365 // joinErrors is implemented in terms of join.
366 friend Error joinErrors(Error, Error);
367
368public:
369 void log(raw_ostream &OS) const override {
370 OS << "Multiple errors:\n";
371 for (auto &ErrPayload : Payloads) {
372 ErrPayload->log(OS);
373 OS << "\n";
374 }
375 }
376
377 std::error_code convertToErrorCode() const override;
378
379 // Used by ErrorInfo::classID.
380 static char ID;
381
382private:
383 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
384 std::unique_ptr<ErrorInfoBase> Payload2) {
385 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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__))
386 "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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__));
387 Payloads.push_back(std::move(Payload1));
388 Payloads.push_back(std::move(Payload2));
389 }
390
391 static Error join(Error E1, Error E2) {
392 if (!E1)
22
←
Assuming the condition is false
→
23
←
Taking false branch
→
393 return E2;
394 if (!E2)
24
←
Assuming the condition is false
→
25
←
Taking false branch
→
395 return E1;
396 if (E1.isA<ErrorList>()) {
26
←
Assuming the condition is false
→
27
←
Taking false branch
→
397 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
398 if (E2.isA<ErrorList>()) {
399 auto E2Payload = E2.takePayload();
400 auto &E2List = static_cast<ErrorList &>(*E2Payload);
401 for (auto &Payload : E2List.Payloads)
402 E1List.Payloads.push_back(std::move(Payload));
403 } else
404 E1List.Payloads.push_back(E2.takePayload());
405
406 return E1;
407 }
408 if (E2.isA<ErrorList>()) {
28
←
Assuming the condition is false
→
29
←
Taking false branch
→
409 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
410 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
411 return E2;
412 }
413 return Error(std::unique_ptr<ErrorList>(
31
←
Calling constructor for 'Error'
→
414 new ErrorList(E1.takePayload(), E2.takePayload())));
30
←
Memory is allocated
→
415 }
416
417 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
418};
419
420/// Concatenate errors. The resulting Error is unchecked, and contains the
421/// ErrorInfo(s), if any, contained in E1, followed by the
422/// ErrorInfo(s), if any, contained in E2.
423inline Error joinErrors(Error E1, Error E2) {
424 return ErrorList::join(std::move(E1), std::move(E2));
425}
426
427/// Tagged union holding either a T or a Error.
428///
429/// This class parallels ErrorOr, but replaces error_code with Error. Since
430/// Error cannot be copied, this class replaces getError() with
431/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
432/// error class type.
433template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
434 template <class T1> friend class ExpectedAsOutParameter;
435 template <class OtherT> friend class Expected;
436
437 static const bool isRef = std::is_reference<T>::value;
438
439 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
440
441 using error_type = std::unique_ptr<ErrorInfoBase>;
442
443public:
444 using storage_type = typename std::conditional<isRef, wrap, T>::type;
445 using value_type = T;
446
447private:
448 using reference = typename std::remove_reference<T>::type &;
449 using const_reference = const typename std::remove_reference<T>::type &;
450 using pointer = typename std::remove_reference<T>::type *;
451 using const_pointer = const typename std::remove_reference<T>::type *;
452
453public:
454 /// Create an Expected<T> error value from the given Error.
455 Expected(Error Err)
456 : HasError(true)
457#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
458 // Expected is unchecked upon construction in Debug builds.
459 , Unchecked(true)
460#endif
461 {
462 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-9~svn362543/include/llvm/Support/Error.h"
, 462, __PRETTY_FUNCTION__));
463 new (getErrorStorage()) error_type(Err.takePayload());
464 }
465
466 /// Forbid to convert from Error::success() implicitly, this avoids having
467 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
468 /// but triggers the assertion above.
469 Expected(ErrorSuccess) = delete;
470
471 /// Create an Expected<T> success value from the given OtherT value, which
472 /// must be convertible to T.
473 template <typename OtherT>
474 Expected(OtherT &&Val,
475 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
476 * = nullptr)
477 : HasError(false)
478#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
479 // Expected is unchecked upon construction in Debug builds.
480 , Unchecked(true)
481#endif
482 {
483 new (getStorage()) storage_type(std::forward<OtherT>(Val));
484 }
485
486 /// Move construct an Expected<T> value.
487 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
488
489 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
490 /// must be convertible to T.
491 template <class OtherT>
492 Expected(Expected<OtherT> &&Other,
493 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
494 * = nullptr) {
495 moveConstruct(std::move(Other));
496 }
497
498 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
499 /// isn't convertible to T.
500 template <class OtherT>
501 explicit Expected(
502 Expected<OtherT> &&Other,
503 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
504 nullptr) {
505 moveConstruct(std::move(Other));
506 }
507
508 /// Move-assign from another Expected<T>.
509 Expected &operator=(Expected &&Other) {
510 moveAssign(std::move(Other));
511 return *this;
512 }
513
514 /// Destroy an Expected<T>.
515 ~Expected() {
516 assertIsChecked();
517 if (!HasError)
518 getStorage()->~storage_type();
519 else
520 getErrorStorage()->~error_type();
521 }
522
523 /// Return false if there is an error.
524 explicit operator bool() {
525#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
526 Unchecked = HasError;
527#endif
528 return !HasError;
529 }
530
531 /// Returns a reference to the stored T value.
532 reference get() {
533 assertIsChecked();
534 return *getStorage();
535 }
536
537 /// Returns a const reference to the stored T value.
538 const_reference get() const {
539 assertIsChecked();
540 return const_cast<Expected<T> *>(this)->get();
541 }
542
543 /// Check that this Expected<T> is an error of type ErrT.
544 template <typename ErrT> bool errorIsA() const {
545 return HasError && (*getErrorStorage())->template isA<ErrT>();
546 }
547
548 /// Take ownership of the stored error.
549 /// After calling this the Expected<T> is in an indeterminate state that can
550 /// only be safely destructed. No further calls (beside the destructor) should
551 /// be made on the Expected<T> vaule.
552 Error takeError() {
553#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
554 Unchecked = false;
555#endif
556 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
557 }
558
559 /// Returns a pointer to the stored T value.
560 pointer operator->() {
561 assertIsChecked();
562 return toPointer(getStorage());
563 }
564
565 /// Returns a const pointer to the stored T value.
566 const_pointer operator->() const {
567 assertIsChecked();
568 return toPointer(getStorage());
569 }
570
571 /// Returns a reference to the stored T value.
572 reference operator*() {
573 assertIsChecked();
574 return *getStorage();
575 }
576
577 /// Returns a const reference to the stored T value.
578 const_reference operator*() const {
579 assertIsChecked();
580 return *getStorage();
581 }
582
583private:
584 template <class T1>
585 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
586 return &a == &b;
587 }
588
589 template <class T1, class T2>
590 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
591 return false;
592 }
593
594 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
595 HasError = Other.HasError;
596#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
597 Unchecked = true;
598 Other.Unchecked = false;
599#endif
600
601 if (!HasError)
602 new (getStorage()) storage_type(std::move(*Other.getStorage()));
603 else
604 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
605 }
606
607 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
608 assertIsChecked();
609
610 if (compareThisIfSameType(*this, Other))
611 return;
612
613 this->~Expected();
614 new (this) Expected(std::move(Other));
615 }
616
617 pointer toPointer(pointer Val) { return Val; }
618
619 const_pointer toPointer(const_pointer Val) const { return Val; }
620
621 pointer toPointer(wrap *Val) { return &Val->get(); }
622
623 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
624
625 storage_type *getStorage() {
626 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-9~svn362543/include/llvm/Support/Error.h"
, 626, __PRETTY_FUNCTION__));
627 return reinterpret_cast<storage_type *>(TStorage.buffer);
628 }
629
630 const storage_type *getStorage() const {
631 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-9~svn362543/include/llvm/Support/Error.h"
, 631, __PRETTY_FUNCTION__));
632 return reinterpret_cast<const storage_type *>(TStorage.buffer);
633 }
634
635 error_type *getErrorStorage() {
636 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-9~svn362543/include/llvm/Support/Error.h"
, 636, __PRETTY_FUNCTION__));
637 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
638 }
639
640 const error_type *getErrorStorage() const {
641 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-9~svn362543/include/llvm/Support/Error.h"
, 641, __PRETTY_FUNCTION__));
642 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
643 }
644
645 // Used by ExpectedAsOutParameter to reset the checked flag.
646 void setUnchecked() {
647#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
648 Unchecked = true;
649#endif
650 }
651
652#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
653 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
654 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
655 void fatalUncheckedExpected() const {
656 dbgs() << "Expected<T> must be checked before access or destruction.\n";
657 if (HasError) {
658 dbgs() << "Unchecked Expected<T> contained error:\n";
659 (*getErrorStorage())->log(dbgs());
660 } else
661 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
662 "values in success mode must still be checked prior to being "
663 "destroyed).\n";
664 abort();
665 }
666#endif
667
668 void assertIsChecked() {
669#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
670 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
671 fatalUncheckedExpected();
672#endif
673 }
674
675 union {
676 AlignedCharArrayUnion<storage_type> TStorage;
677 AlignedCharArrayUnion<error_type> ErrorStorage;
678 };
679 bool HasError : 1;
680#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
681 bool Unchecked : 1;
682#endif
683};
684
685/// Report a serious error, calling any installed error handler. See
686/// ErrorHandling.h.
687LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
688 bool gen_crash_diag = true);
689
690/// Report a fatal error if Err is a failure value.
691///
692/// This function can be used to wrap calls to fallible functions ONLY when it
693/// is known that the Error will always be a success value. E.g.
694///
695/// @code{.cpp}
696/// // foo only attempts the fallible operation if DoFallibleOperation is
697/// // true. If DoFallibleOperation is false then foo always returns
698/// // Error::success().
699/// Error foo(bool DoFallibleOperation);
700///
701/// cantFail(foo(false));
702/// @endcode
703inline void cantFail(Error Err, const char *Msg = nullptr) {
704 if (Err) {
705 if (!Msg)
706 Msg = "Failure value returned from cantFail wrapped call";
707 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 707);
708 }
709}
710
711/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
712/// returns the contained value.
713///
714/// This function can be used to wrap calls to fallible functions ONLY when it
715/// is known that the Error will always be a success value. E.g.
716///
717/// @code{.cpp}
718/// // foo only attempts the fallible operation if DoFallibleOperation is
719/// // true. If DoFallibleOperation is false then foo always returns an int.
720/// Expected<int> foo(bool DoFallibleOperation);
721///
722/// int X = cantFail(foo(false));
723/// @endcode
724template <typename T>
725T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
726 if (ValOrErr)
727 return std::move(*ValOrErr);
728 else {
729 if (!Msg)
730 Msg = "Failure value returned from cantFail wrapped call";
731 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 731);
732 }
733}
734
735/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
736/// returns the contained reference.
737///
738/// This function can be used to wrap calls to fallible functions ONLY when it
739/// is known that the Error will always be a success value. E.g.
740///
741/// @code{.cpp}
742/// // foo only attempts the fallible operation if DoFallibleOperation is
743/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
744/// Expected<Bar&> foo(bool DoFallibleOperation);
745///
746/// Bar &X = cantFail(foo(false));
747/// @endcode
748template <typename T>
749T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
750 if (ValOrErr)
751 return *ValOrErr;
752 else {
753 if (!Msg)
754 Msg = "Failure value returned from cantFail wrapped call";
755 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 755);
756 }
757}
758
759/// Helper for testing applicability of, and applying, handlers for
760/// ErrorInfo types.
761template <typename HandlerT>
762class ErrorHandlerTraits
763 : public ErrorHandlerTraits<decltype(
764 &std::remove_reference<HandlerT>::type::operator())> {};
765
766// Specialization functions of the form 'Error (const ErrT&)'.
767template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
768public:
769 static bool appliesTo(const ErrorInfoBase &E) {
770 return E.template isA<ErrT>();
771 }
772
773 template <typename HandlerT>
774 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
775 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-9~svn362543/include/llvm/Support/Error.h"
, 775, __PRETTY_FUNCTION__));
776 return H(static_cast<ErrT &>(*E));
777 }
778};
779
780// Specialization functions of the form 'void (const ErrT&)'.
781template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
782public:
783 static bool appliesTo(const ErrorInfoBase &E) {
784 return E.template isA<ErrT>();
785 }
786
787 template <typename HandlerT>
788 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
789 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-9~svn362543/include/llvm/Support/Error.h"
, 789, __PRETTY_FUNCTION__));
790 H(static_cast<ErrT &>(*E));
791 return Error::success();
792 }
793};
794
795/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
796template <typename ErrT>
797class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
798public:
799 static bool appliesTo(const ErrorInfoBase &E) {
800 return E.template isA<ErrT>();
801 }
802
803 template <typename HandlerT>
804 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
805 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-9~svn362543/include/llvm/Support/Error.h"
, 805, __PRETTY_FUNCTION__));
806 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
807 return H(std::move(SubE));
808 }
809};
810
811/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
812template <typename ErrT>
813class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
814public:
815 static bool appliesTo(const ErrorInfoBase &E) {
816 return E.template isA<ErrT>();
817 }
818
819 template <typename HandlerT>
820 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
821 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-9~svn362543/include/llvm/Support/Error.h"
, 821, __PRETTY_FUNCTION__));
822 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
823 H(std::move(SubE));
824 return Error::success();
825 }
826};
827
828// Specialization for member functions of the form 'RetT (const ErrT&)'.
829template <typename C, typename RetT, typename ErrT>
830class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
831 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
832
833// Specialization for member functions of the form 'RetT (const ErrT&) const'.
834template <typename C, typename RetT, typename ErrT>
835class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
836 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
837
838// Specialization for member functions of the form 'RetT (const ErrT&)'.
839template <typename C, typename RetT, typename ErrT>
840class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
841 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
842
843// Specialization for member functions of the form 'RetT (const ErrT&) const'.
844template <typename C, typename RetT, typename ErrT>
845class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
846 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
847
848/// Specialization for member functions of the form
849/// 'RetT (std::unique_ptr<ErrT>)'.
850template <typename C, typename RetT, typename ErrT>
851class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
852 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
853
854/// Specialization for member functions of the form
855/// 'RetT (std::unique_ptr<ErrT>) const'.
856template <typename C, typename RetT, typename ErrT>
857class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
858 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
859
860inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
861 return Error(std::move(Payload));
862}
863
864template <typename HandlerT, typename... HandlerTs>
865Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
866 HandlerT &&Handler, HandlerTs &&... Handlers) {
867 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
868 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
869 std::move(Payload));
870 return handleErrorImpl(std::move(Payload),
871 std::forward<HandlerTs>(Handlers)...);
872}
873
874/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
875/// unhandled errors (or Errors returned by handlers) are re-concatenated and
876/// returned.
877/// Because this function returns an error, its result must also be checked
878/// or returned. If you intend to handle all errors use handleAllErrors
879/// (which returns void, and will abort() on unhandled errors) instead.
880template <typename... HandlerTs>
881Error handleErrors(Error E, HandlerTs &&... Hs) {
882 if (!E)
17
←
Assuming the condition is false
→
18
←
Taking false branch
→
883 return Error::success();
884
885 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
886
887 if (Payload->isA<ErrorList>()) {
19
←
Assuming the condition is true
→
20
←
Taking true branch
→
888 ErrorList &List = static_cast<ErrorList &>(*Payload);
889 Error R;
890 for (auto &P : List.Payloads)
891 R = ErrorList::join(
21
←
Calling 'ErrorList::join'
→
892 std::move(R),
893 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
894 return R;
895 }
896
897 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
898}
899
900/// Behaves the same as handleErrors, except that by contract all errors
901/// *must* be handled by the given handlers (i.e. there must be no remaining
902/// errors after running the handlers, or llvm_unreachable is called).
903template <typename... HandlerTs>
904void handleAllErrors(Error E, HandlerTs &&... Handlers) {
905 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
16
←
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h:982:35)>'
→
906}
907
908/// Check that E is a non-error, then drop it.
909/// If E is an error, llvm_unreachable will be called.
910inline void handleAllErrors(Error E) {
911 cantFail(std::move(E));
912}
913
914/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
915///
916/// If the incoming value is a success value it is returned unmodified. If it
917/// is a failure value then it the contained error is passed to handleErrors.
918/// If handleErrors is able to handle the error then the RecoveryPath functor
919/// is called to supply the final result. If handleErrors is not able to
920/// handle all errors then the unhandled errors are returned.
921///
922/// This utility enables the follow pattern:
923///
924/// @code{.cpp}
925/// enum FooStrategy { Aggressive, Conservative };
926/// Expected<Foo> foo(FooStrategy S);
927///
928/// auto ResultOrErr =
929/// handleExpected(
930/// foo(Aggressive),
931/// []() { return foo(Conservative); },
932/// [](AggressiveStrategyError&) {
933/// // Implicitly conusme this - we'll recover by using a conservative
934/// // strategy.
935/// });
936///
937/// @endcode
938template <typename T, typename RecoveryFtor, typename... HandlerTs>
939Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
940 HandlerTs &&... Handlers) {
941 if (ValOrErr)
942 return ValOrErr;
943
944 if (auto Err = handleErrors(ValOrErr.takeError(),
945 std::forward<HandlerTs>(Handlers)...))
946 return std::move(Err);
947
948 return RecoveryPath();
949}
950
951/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
952/// will be printed before the first one is logged. A newline will be printed
953/// after each error.
954///
955/// This function is compatible with the helpers from Support/WithColor.h. You
956/// can pass any of them as the OS. Please consider using them instead of
957/// including 'error: ' in the ErrorBanner.
958///
959/// This is useful in the base level of your program to allow clean termination
960/// (allowing clean deallocation of resources, etc.), while reporting error
961/// information to the user.
962void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
963
964/// Write all error messages (if any) in E to a string. The newline character
965/// is used to separate error messages.
966inline std::string toString(Error E) {
967 SmallVector<std::string, 2> Errors;
968 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
969 Errors.push_back(EI.message());
970 });
971 return join(Errors.begin(), Errors.end(), "\n");
972}
973
974/// Consume a Error without doing anything. This method should be used
975/// only where an error can be considered a reasonable and expected return
976/// value.
977///
978/// Uses of this method are potentially indicative of design problems: If it's
979/// legitimate to do nothing while processing an "error", the error-producer
980/// might be more clearly refactored to return an Optional<T>.
981inline void consumeError(Error Err) {
982 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
15
←
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h:982:35)>'
→
983}
984
985/// Helper for converting an Error to a bool.
986///
987/// This method returns true if Err is in an error state, or false if it is
988/// in a success state. Puts Err in a checked state in both cases (unlike
989/// Error::operator bool(), which only does this for success states).
990inline bool errorToBool(Error Err) {
991 bool IsError = static_cast<bool>(Err);
992 if (IsError)
993 consumeError(std::move(Err));
994 return IsError;
995}
996
997/// Helper for Errors used as out-parameters.
998///
999/// This helper is for use with the Error-as-out-parameter idiom, where an error
1000/// is passed to a function or method by reference, rather than being returned.
1001/// In such cases it is helpful to set the checked bit on entry to the function
1002/// so that the error can be written to (unchecked Errors abort on assignment)
1003/// and clear the checked bit on exit so that clients cannot accidentally forget
1004/// to check the result. This helper performs these actions automatically using
1005/// RAII:
1006///
1007/// @code{.cpp}
1008/// Result foo(Error &Err) {
1009/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1010/// // <body of foo>
1011/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1012/// }
1013/// @endcode
1014///
1015/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1016/// used with optional Errors (Error pointers that are allowed to be null). If
1017/// ErrorAsOutParameter took an Error reference, an instance would have to be
1018/// created inside every condition that verified that Error was non-null. By
1019/// taking an Error pointer we can just create one instance at the top of the
1020/// function.
1021class ErrorAsOutParameter {
1022public:
1023 ErrorAsOutParameter(Error *Err) : Err(Err) {
1024 // Raise the checked bit if Err is success.
1025 if (Err)
1026 (void)!!*Err;
1027 }
1028
1029 ~ErrorAsOutParameter() {
1030 // Clear the checked bit.
1031 if (Err && !*Err)
1032 *Err = Error::success();
1033 }
1034
1035private:
1036 Error *Err;
1037};
1038
1039/// Helper for Expected<T>s used as out-parameters.
1040///
1041/// See ErrorAsOutParameter.
1042template <typename T>
1043class ExpectedAsOutParameter {
1044public:
1045 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1046 : ValOrErr(ValOrErr) {
1047 if (ValOrErr)
1048 (void)!!*ValOrErr;
1049 }
1050
1051 ~ExpectedAsOutParameter() {
1052 if (ValOrErr)
1053 ValOrErr->setUnchecked();
1054 }
1055
1056private:
1057 Expected<T> *ValOrErr;
1058};
1059
1060/// This class wraps a std::error_code in a Error.
1061///
1062/// This is useful if you're writing an interface that returns a Error
1063/// (or Expected) and you want to call code that still returns
1064/// std::error_codes.
1065class ECError : public ErrorInfo<ECError> {
1066 friend Error errorCodeToError(std::error_code);
1067
1068 virtual void anchor() override;
1069
1070public:
1071 void setErrorCode(std::error_code EC) { this->EC = EC; }
1072 std::error_code convertToErrorCode() const override { return EC; }
1073 void log(raw_ostream &OS) const override { OS << EC.message(); }
1074
1075 // Used by ErrorInfo::classID.
1076 static char ID;
1077
1078protected:
1079 ECError() = default;
1080 ECError(std::error_code EC) : EC(EC) {}
1081
1082 std::error_code EC;
1083};
1084
1085/// The value returned by this function can be returned from convertToErrorCode
1086/// for Error values where no sensible translation to std::error_code exists.
1087/// It should only be used in this situation, and should never be used where a
1088/// sensible conversion to std::error_code is available, as attempts to convert
1089/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1090///error to try to convert such a value).
1091std::error_code inconvertibleErrorCode();
1092
1093/// Helper for converting an std::error_code to a Error.
1094Error errorCodeToError(std::error_code EC);
1095
1096/// Helper for converting an ECError to a std::error_code.
1097///
1098/// This method requires that Err be Error() or an ECError, otherwise it
1099/// will trigger a call to abort().
1100std::error_code errorToErrorCode(Error Err);
1101
1102/// Convert an ErrorOr<T> to an Expected<T>.
1103template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1104 if (auto EC = EO.getError())
1105 return errorCodeToError(EC);
1106 return std::move(*EO);
1107}
1108
1109/// Convert an Expected<T> to an ErrorOr<T>.
1110template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1111 if (auto Err = E.takeError())
1112 return errorToErrorCode(std::move(Err));
1113 return std::move(*E);
1114}
1115
1116/// This class wraps a string in an Error.
1117///
1118/// StringError is useful in cases where the client is not expected to be able
1119/// to consume the specific error message programmatically (for example, if the
1120/// error message is to be presented to the user).
1121///
1122/// StringError can also be used when additional information is to be printed
1123/// along with a error_code message. Depending on the constructor called, this
1124/// class can either display:
1125/// 1. the error_code message (ECError behavior)
1126/// 2. a string
1127/// 3. the error_code message and a string
1128///
1129/// These behaviors are useful when subtyping is required; for example, when a
1130/// specific library needs an explicit error type. In the example below,
1131/// PDBError is derived from StringError:
1132///
1133/// @code{.cpp}
1134/// Expected<int> foo() {
1135/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1136/// "Additional information");
1137/// }
1138/// @endcode
1139///
1140class StringError : public ErrorInfo<StringError> {
1141public:
1142 static char ID;
1143
1144 // Prints EC + S and converts to EC
1145 StringError(std::error_code EC, const Twine &S = Twine());
1146
1147 // Prints S and converts to EC
1148 StringError(const Twine &S, std::error_code EC);
1149
1150 void log(raw_ostream &OS) const override;
1151 std::error_code convertToErrorCode() const override;
1152
1153 const std::string &getMessage() const { return Msg; }
1154
1155private:
1156 std::string Msg;
1157 std::error_code EC;
1158 const bool PrintMsgOnly = false;
1159};
1160
1161/// Create formatted StringError object.
1162template <typename... Ts>
1163Error createStringError(std::error_code EC, char const *Fmt,
1164 const Ts &... Vals) {
1165 std::string Buffer;
1166 raw_string_ostream Stream(Buffer);
1167 Stream << format(Fmt, Vals...);
1168 return make_error<StringError>(Stream.str(), EC);
1169}
1170
1171Error createStringError(std::error_code EC, char const *Msg);
1172
1173/// This class wraps a filename and another Error.
1174///
1175/// In some cases, an error needs to live along a 'source' name, in order to
1176/// show more detailed information to the user.
1177class FileError final : public ErrorInfo<FileError> {
1178
1179 friend Error createFileError(const Twine &, Error);
1180 friend Error createFileError(const Twine &, size_t, Error);
1181
1182public:
1183 void log(raw_ostream &OS) const override {
1184 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-9~svn362543/include/llvm/Support/Error.h"
, 1184, __PRETTY_FUNCTION__));
1185 OS << "'" << FileName << "': ";
1186 if (Line.hasValue())
1187 OS << "line " << Line.getValue() << ": ";
1188 Err->log(OS);
1189 }
1190
1191 Error takeError() { return Error(std::move(Err)); }
1192
1193 std::error_code convertToErrorCode() const override;
1194
1195 // Used by ErrorInfo::classID.
1196 static char ID;
1197
1198private:
1199 FileError(const Twine &F, Optional<size_t> LineNum,
1200 std::unique_ptr<ErrorInfoBase> E) {
1201 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-9~svn362543/include/llvm/Support/Error.h"
, 1201, __PRETTY_FUNCTION__));
1202 assert(!F.isTriviallyEmpty() &&((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__))
1203 "The file name provided to FileError must not be empty.")((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__));
1204 FileName = F.str();
1205 Err = std::move(E);
1206 Line = std::move(LineNum);
1207 }
1208
1209 static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1210 return Error(
1211 std::unique_ptr<FileError>(new FileError(F, Line, E.takePayload())));
1212 }
1213
1214 std::string FileName;
1215 Optional<size_t> Line;
1216 std::unique_ptr<ErrorInfoBase> Err;
1217};
1218
1219/// Concatenate a source file path and/or name with an Error. The resulting
1220/// Error is unchecked.
1221inline Error createFileError(const Twine &F, Error E) {
1222 return FileError::build(F, Optional<size_t>(), std::move(E));
1223}
1224
1225/// Concatenate a source file path and/or name with line number and an Error.
1226/// The resulting Error is unchecked.
1227inline Error createFileError(const Twine &F, size_t Line, Error E) {
1228 return FileError::build(F, Optional<size_t>(Line), std::move(E));
1229}
1230
1231/// Concatenate a source file path and/or name with a std::error_code
1232/// to form an Error object.
1233inline Error createFileError(const Twine &F, std::error_code EC) {
1234 return createFileError(F, errorCodeToError(EC));
1235}
1236
1237/// Concatenate a source file path and/or name with line number and
1238/// std::error_code to form an Error object.
1239inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1240 return createFileError(F, Line, errorCodeToError(EC));
1241}
1242
1243Error createFileError(const Twine &F, ErrorSuccess) = delete;
1244
1245/// Helper for check-and-exit error handling.
1246///
1247/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1248///
1249class ExitOnError {
1250public:
1251 /// Create an error on exit helper.
1252 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1253 : Banner(std::move(Banner)),
1254 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1255
1256 /// Set the banner string for any errors caught by operator().
1257 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1258
1259 /// Set the exit-code mapper function.
1260 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1261 this->GetExitCode = std::move(GetExitCode);
1262 }
1263
1264 /// Check Err. If it's in a failure state log the error(s) and exit.
1265 void operator()(Error Err) const { checkError(std::move(Err)); }
1266
1267 /// Check E. If it's in a success state then return the contained value. If
1268 /// it's in a failure state log the error(s) and exit.
1269 template <typename T> T operator()(Expected<T> &&E) const {
1270 checkError(E.takeError());
1271 return std::move(*E);
1272 }
1273
1274 /// Check E. If it's in a success state then return the contained reference. If
1275 /// it's in a failure state log the error(s) and exit.
1276 template <typename T> T& operator()(Expected<T&> &&E) const {
1277 checkError(E.takeError());
1278 return *E;
1279 }
1280
1281private:
1282 void checkError(Error Err) const {
1283 if (Err) {
1284 int ExitCode = GetExitCode(Err);
1285 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1286 exit(ExitCode);
1287 }
1288 }
1289
1290 std::string Banner;
1291 std::function<int(const Error &)> GetExitCode;
1292};
1293
1294/// Conversion from Error to LLVMErrorRef for C error bindings.
1295inline LLVMErrorRef wrap(Error Err) {
1296 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1297}
1298
1299/// Conversion from LLVMErrorRef to Error for C error bindings.
1300inline Error unwrap(LLVMErrorRef ErrRef) {
1301 return Error(std::unique_ptr<ErrorInfoBase>(
1302 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1303}
1304
1305} // end namespace llvm
1306
1307#endif // LLVM_SUPPORT_ERROR_H