| File: | build/source/clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp |
| Warning: | line 421, column 9 1st function call argument is an uninitialized value |
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| 1 | //===--- SignalHandlerCheck.cpp - clang-tidy ------------------------------===// | ||||||
| 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 | #include "SignalHandlerCheck.h" | ||||||
| 10 | #include "clang/ASTMatchers/ASTMatchFinder.h" | ||||||
| 11 | #include "llvm/ADT/DepthFirstIterator.h" | ||||||
| 12 | #include "llvm/ADT/STLExtras.h" | ||||||
| 13 | |||||||
| 14 | // This is the minimal set of safe functions. | ||||||
| 15 | // https://wiki.sei.cmu.edu/confluence/display/c/SIG30-C.+Call+only+asynchronous-safe+functions+within+signal+handlers | ||||||
| 16 | constexpr llvm::StringLiteral MinimalConformingFunctions[] = { | ||||||
| 17 | "signal", "abort", "_Exit", "quick_exit"}; | ||||||
| 18 | |||||||
| 19 | // The POSIX-defined set of safe functions. | ||||||
| 20 | // https://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html#tag_15_04_03 | ||||||
| 21 | // 'quick_exit' is added to the set additionally because it looks like the | ||||||
| 22 | // mentioned POSIX specification was not updated after 'quick_exit' appeared | ||||||
| 23 | // in the C11 standard. | ||||||
| 24 | // Also, we want to keep the "minimal set" a subset of the "POSIX set". | ||||||
| 25 | // The list is repeated in bugprone-signal-handler.rst and should be kept up to date. | ||||||
| 26 | constexpr llvm::StringLiteral POSIXConformingFunctions[] = { | ||||||
| 27 | "_Exit", | ||||||
| 28 | "_exit", | ||||||
| 29 | "abort", | ||||||
| 30 | "accept", | ||||||
| 31 | "access", | ||||||
| 32 | "aio_error", | ||||||
| 33 | "aio_return", | ||||||
| 34 | "aio_suspend", | ||||||
| 35 | "alarm", | ||||||
| 36 | "bind", | ||||||
| 37 | "cfgetispeed", | ||||||
| 38 | "cfgetospeed", | ||||||
| 39 | "cfsetispeed", | ||||||
| 40 | "cfsetospeed", | ||||||
| 41 | "chdir", | ||||||
| 42 | "chmod", | ||||||
| 43 | "chown", | ||||||
| 44 | "clock_gettime", | ||||||
| 45 | "close", | ||||||
| 46 | "connect", | ||||||
| 47 | "creat", | ||||||
| 48 | "dup", | ||||||
| 49 | "dup2", | ||||||
| 50 | "execl", | ||||||
| 51 | "execle", | ||||||
| 52 | "execv", | ||||||
| 53 | "execve", | ||||||
| 54 | "faccessat", | ||||||
| 55 | "fchdir", | ||||||
| 56 | "fchmod", | ||||||
| 57 | "fchmodat", | ||||||
| 58 | "fchown", | ||||||
| 59 | "fchownat", | ||||||
| 60 | "fcntl", | ||||||
| 61 | "fdatasync", | ||||||
| 62 | "fexecve", | ||||||
| 63 | "ffs", | ||||||
| 64 | "fork", | ||||||
| 65 | "fstat", | ||||||
| 66 | "fstatat", | ||||||
| 67 | "fsync", | ||||||
| 68 | "ftruncate", | ||||||
| 69 | "futimens", | ||||||
| 70 | "getegid", | ||||||
| 71 | "geteuid", | ||||||
| 72 | "getgid", | ||||||
| 73 | "getgroups", | ||||||
| 74 | "getpeername", | ||||||
| 75 | "getpgrp", | ||||||
| 76 | "getpid", | ||||||
| 77 | "getppid", | ||||||
| 78 | "getsockname", | ||||||
| 79 | "getsockopt", | ||||||
| 80 | "getuid", | ||||||
| 81 | "htonl", | ||||||
| 82 | "htons", | ||||||
| 83 | "kill", | ||||||
| 84 | "link", | ||||||
| 85 | "linkat", | ||||||
| 86 | "listen", | ||||||
| 87 | "longjmp", | ||||||
| 88 | "lseek", | ||||||
| 89 | "lstat", | ||||||
| 90 | "memccpy", | ||||||
| 91 | "memchr", | ||||||
| 92 | "memcmp", | ||||||
| 93 | "memcpy", | ||||||
| 94 | "memmove", | ||||||
| 95 | "memset", | ||||||
| 96 | "mkdir", | ||||||
| 97 | "mkdirat", | ||||||
| 98 | "mkfifo", | ||||||
| 99 | "mkfifoat", | ||||||
| 100 | "mknod", | ||||||
| 101 | "mknodat", | ||||||
| 102 | "ntohl", | ||||||
| 103 | "ntohs", | ||||||
| 104 | "open", | ||||||
| 105 | "openat", | ||||||
| 106 | "pause", | ||||||
| 107 | "pipe", | ||||||
| 108 | "poll", | ||||||
| 109 | "posix_trace_event", | ||||||
| 110 | "pselect", | ||||||
| 111 | "pthread_kill", | ||||||
| 112 | "pthread_self", | ||||||
| 113 | "pthread_sigmask", | ||||||
| 114 | "quick_exit", | ||||||
| 115 | "raise", | ||||||
| 116 | "read", | ||||||
| 117 | "readlink", | ||||||
| 118 | "readlinkat", | ||||||
| 119 | "recv", | ||||||
| 120 | "recvfrom", | ||||||
| 121 | "recvmsg", | ||||||
| 122 | "rename", | ||||||
| 123 | "renameat", | ||||||
| 124 | "rmdir", | ||||||
| 125 | "select", | ||||||
| 126 | "sem_post", | ||||||
| 127 | "send", | ||||||
| 128 | "sendmsg", | ||||||
| 129 | "sendto", | ||||||
| 130 | "setgid", | ||||||
| 131 | "setpgid", | ||||||
| 132 | "setsid", | ||||||
| 133 | "setsockopt", | ||||||
| 134 | "setuid", | ||||||
| 135 | "shutdown", | ||||||
| 136 | "sigaction", | ||||||
| 137 | "sigaddset", | ||||||
| 138 | "sigdelset", | ||||||
| 139 | "sigemptyset", | ||||||
| 140 | "sigfillset", | ||||||
| 141 | "sigismember", | ||||||
| 142 | "siglongjmp", | ||||||
| 143 | "signal", | ||||||
| 144 | "sigpause", | ||||||
| 145 | "sigpending", | ||||||
| 146 | "sigprocmask", | ||||||
| 147 | "sigqueue", | ||||||
| 148 | "sigset", | ||||||
| 149 | "sigsuspend", | ||||||
| 150 | "sleep", | ||||||
| 151 | "sockatmark", | ||||||
| 152 | "socket", | ||||||
| 153 | "socketpair", | ||||||
| 154 | "stat", | ||||||
| 155 | "stpcpy", | ||||||
| 156 | "stpncpy", | ||||||
| 157 | "strcat", | ||||||
| 158 | "strchr", | ||||||
| 159 | "strcmp", | ||||||
| 160 | "strcpy", | ||||||
| 161 | "strcspn", | ||||||
| 162 | "strlen", | ||||||
| 163 | "strncat", | ||||||
| 164 | "strncmp", | ||||||
| 165 | "strncpy", | ||||||
| 166 | "strnlen", | ||||||
| 167 | "strpbrk", | ||||||
| 168 | "strrchr", | ||||||
| 169 | "strspn", | ||||||
| 170 | "strstr", | ||||||
| 171 | "strtok_r", | ||||||
| 172 | "symlink", | ||||||
| 173 | "symlinkat", | ||||||
| 174 | "tcdrain", | ||||||
| 175 | "tcflow", | ||||||
| 176 | "tcflush", | ||||||
| 177 | "tcgetattr", | ||||||
| 178 | "tcgetpgrp", | ||||||
| 179 | "tcsendbreak", | ||||||
| 180 | "tcsetattr", | ||||||
| 181 | "tcsetpgrp", | ||||||
| 182 | "time", | ||||||
| 183 | "timer_getoverrun", | ||||||
| 184 | "timer_gettime", | ||||||
| 185 | "timer_settime", | ||||||
| 186 | "times", | ||||||
| 187 | "umask", | ||||||
| 188 | "uname", | ||||||
| 189 | "unlink", | ||||||
| 190 | "unlinkat", | ||||||
| 191 | "utime", | ||||||
| 192 | "utimensat", | ||||||
| 193 | "utimes", | ||||||
| 194 | "wait", | ||||||
| 195 | "waitpid", | ||||||
| 196 | "wcpcpy", | ||||||
| 197 | "wcpncpy", | ||||||
| 198 | "wcscat", | ||||||
| 199 | "wcschr", | ||||||
| 200 | "wcscmp", | ||||||
| 201 | "wcscpy", | ||||||
| 202 | "wcscspn", | ||||||
| 203 | "wcslen", | ||||||
| 204 | "wcsncat", | ||||||
| 205 | "wcsncmp", | ||||||
| 206 | "wcsncpy", | ||||||
| 207 | "wcsnlen", | ||||||
| 208 | "wcspbrk", | ||||||
| 209 | "wcsrchr", | ||||||
| 210 | "wcsspn", | ||||||
| 211 | "wcsstr", | ||||||
| 212 | "wcstok", | ||||||
| 213 | "wmemchr", | ||||||
| 214 | "wmemcmp", | ||||||
| 215 | "wmemcpy", | ||||||
| 216 | "wmemmove", | ||||||
| 217 | "wmemset", | ||||||
| 218 | "write"}; | ||||||
| 219 | |||||||
| 220 | using namespace clang::ast_matchers; | ||||||
| 221 | |||||||
| 222 | namespace clang::tidy { | ||||||
| 223 | |||||||
| 224 | template <> | ||||||
| 225 | struct OptionEnumMapping< | ||||||
| 226 | bugprone::SignalHandlerCheck::AsyncSafeFunctionSetKind> { | ||||||
| 227 | static llvm::ArrayRef<std::pair< | ||||||
| 228 | bugprone::SignalHandlerCheck::AsyncSafeFunctionSetKind, StringRef>> | ||||||
| 229 | getEnumMapping() { | ||||||
| 230 | static constexpr std::pair< | ||||||
| 231 | bugprone::SignalHandlerCheck::AsyncSafeFunctionSetKind, StringRef> | ||||||
| 232 | Mapping[] = { | ||||||
| 233 | {bugprone::SignalHandlerCheck::AsyncSafeFunctionSetKind::Minimal, | ||||||
| 234 | "minimal"}, | ||||||
| 235 | {bugprone::SignalHandlerCheck::AsyncSafeFunctionSetKind::POSIX, | ||||||
| 236 | "POSIX"}, | ||||||
| 237 | }; | ||||||
| 238 | return ArrayRef(Mapping); | ||||||
| 239 | } | ||||||
| 240 | }; | ||||||
| 241 | |||||||
| 242 | namespace bugprone { | ||||||
| 243 | |||||||
| 244 | namespace { | ||||||
| 245 | |||||||
| 246 | /// Returns if a function is declared inside a system header. | ||||||
| 247 | /// These functions are considered to be "standard" (system-provided) library | ||||||
| 248 | /// functions. | ||||||
| 249 | bool isStandardFunction(const FunctionDecl *FD) { | ||||||
| 250 | // Find a possible redeclaration in system header. | ||||||
| 251 | // FIXME: Looking at the canonical declaration is not the most exact way | ||||||
| 252 | // to do this. | ||||||
| 253 | |||||||
| 254 | // Most common case will be inclusion directly from a header. | ||||||
| 255 | // This works fine by using canonical declaration. | ||||||
| 256 | // a.c | ||||||
| 257 | // #include <sysheader.h> | ||||||
| 258 | |||||||
| 259 | // Next most common case will be extern declaration. | ||||||
| 260 | // Can't catch this with either approach. | ||||||
| 261 | // b.c | ||||||
| 262 | // extern void sysfunc(void); | ||||||
| 263 | |||||||
| 264 | // Canonical declaration is the first found declaration, so this works. | ||||||
| 265 | // c.c | ||||||
| 266 | // #include <sysheader.h> | ||||||
| 267 | // extern void sysfunc(void); // redecl won't matter | ||||||
| 268 | |||||||
| 269 | // This does not work with canonical declaration. | ||||||
| 270 | // Probably this is not a frequently used case but may happen (the first | ||||||
| 271 | // declaration can be in a non-system header for example). | ||||||
| 272 | // d.c | ||||||
| 273 | // extern void sysfunc(void); // Canonical declaration, not in system header. | ||||||
| 274 | // #include <sysheader.h> | ||||||
| 275 | |||||||
| 276 | return FD->getASTContext().getSourceManager().isInSystemHeader( | ||||||
| 277 | FD->getCanonicalDecl()->getLocation()); | ||||||
| 278 | } | ||||||
| 279 | |||||||
| 280 | /// Check if a statement is "C++-only". | ||||||
| 281 | /// This includes all statements that have a class name with "CXX" prefix | ||||||
| 282 | /// and every other statement that is declared in file ExprCXX.h. | ||||||
| 283 | bool isCXXOnlyStmt(const Stmt *S) { | ||||||
| 284 | StringRef Name = S->getStmtClassName(); | ||||||
| 285 | if (Name.startswith("CXX")) | ||||||
| 286 | return true; | ||||||
| 287 | // Check for all other class names in ExprCXX.h that have no 'CXX' prefix. | ||||||
| 288 | return isa<ArrayTypeTraitExpr, BuiltinBitCastExpr, CUDAKernelCallExpr, | ||||||
| 289 | CoawaitExpr, CoreturnStmt, CoroutineBodyStmt, CoroutineSuspendExpr, | ||||||
| 290 | CoyieldExpr, DependentCoawaitExpr, DependentScopeDeclRefExpr, | ||||||
| 291 | ExprWithCleanups, ExpressionTraitExpr, FunctionParmPackExpr, | ||||||
| 292 | LambdaExpr, MSDependentExistsStmt, MSPropertyRefExpr, | ||||||
| 293 | MSPropertySubscriptExpr, MaterializeTemporaryExpr, OverloadExpr, | ||||||
| 294 | PackExpansionExpr, SizeOfPackExpr, SubstNonTypeTemplateParmExpr, | ||||||
| 295 | SubstNonTypeTemplateParmPackExpr, TypeTraitExpr, | ||||||
| 296 | UserDefinedLiteral>(S); | ||||||
| 297 | } | ||||||
| 298 | |||||||
| 299 | /// Given a call graph node of a \p Caller function and a \p Callee that is | ||||||
| 300 | /// called from \p Caller, get a \c CallExpr of the corresponding function call. | ||||||
| 301 | /// It is unspecified which call is found if multiple calls exist, but the order | ||||||
| 302 | /// should be deterministic (depend only on the AST). | ||||||
| 303 | Expr *findCallExpr(const CallGraphNode *Caller, const CallGraphNode *Callee) { | ||||||
| 304 | auto FoundCallee = llvm::find_if( | ||||||
| 305 | Caller->callees(), [Callee](const CallGraphNode::CallRecord &Call) { | ||||||
| 306 | return Call.Callee == Callee; | ||||||
| 307 | }); | ||||||
| 308 | assert(FoundCallee != Caller->end() &&(static_cast <bool> (FoundCallee != Caller->end() && "Callee should be called from the caller function here.") ? void (0) : __assert_fail ("FoundCallee != Caller->end() && \"Callee should be called from the caller function here.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 309, __extension__ __PRETTY_FUNCTION__)) | ||||||
| 309 | "Callee should be called from the caller function here.")(static_cast <bool> (FoundCallee != Caller->end() && "Callee should be called from the caller function here.") ? void (0) : __assert_fail ("FoundCallee != Caller->end() && \"Callee should be called from the caller function here.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 309, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 310 | return FoundCallee->CallExpr; | ||||||
| 311 | } | ||||||
| 312 | |||||||
| 313 | SourceRange getSourceRangeOfStmt(const Stmt *S, ASTContext &Ctx) { | ||||||
| 314 | ParentMapContext &PM = Ctx.getParentMapContext(); | ||||||
| 315 | DynTypedNode P = DynTypedNode::create(*S); | ||||||
| 316 | while (P.getSourceRange().isInvalid()) { | ||||||
| 317 | DynTypedNodeList PL = PM.getParents(P); | ||||||
| 318 | if (PL.size() != 1) | ||||||
| 319 | return {}; | ||||||
| 320 | P = PL[0]; | ||||||
| 321 | } | ||||||
| 322 | return P.getSourceRange(); | ||||||
| 323 | } | ||||||
| 324 | |||||||
| 325 | } // namespace | ||||||
| 326 | |||||||
| 327 | AST_MATCHER(FunctionDecl, isStandardFunction)namespace internal { class matcher_isStandardFunctionMatcher : public ::clang::ast_matchers::internal::MatcherInterface< FunctionDecl> { public: explicit matcher_isStandardFunctionMatcher () = default; bool matches(const FunctionDecl &Node, ::clang ::ast_matchers::internal::ASTMatchFinder *Finder, ::clang::ast_matchers ::internal::BoundNodesTreeBuilder *Builder) const override; } ; } inline ::clang::ast_matchers::internal::Matcher<FunctionDecl > isStandardFunction() { return ::clang::ast_matchers::internal ::makeMatcher( new internal::matcher_isStandardFunctionMatcher ()); } inline bool internal::matcher_isStandardFunctionMatcher ::matches( const FunctionDecl &Node, ::clang::ast_matchers ::internal::ASTMatchFinder *Finder, ::clang::ast_matchers::internal ::BoundNodesTreeBuilder *Builder) const { | ||||||
| 328 | return isStandardFunction(&Node); | ||||||
| 329 | } | ||||||
| 330 | |||||||
| 331 | SignalHandlerCheck::SignalHandlerCheck(StringRef Name, | ||||||
| 332 | ClangTidyContext *Context) | ||||||
| 333 | : ClangTidyCheck(Name, Context), | ||||||
| 334 | AsyncSafeFunctionSet(Options.get("AsyncSafeFunctionSet", | ||||||
| 335 | AsyncSafeFunctionSetKind::POSIX)) { | ||||||
| 336 | if (AsyncSafeFunctionSet == AsyncSafeFunctionSetKind::Minimal) { | ||||||
| 337 | for (StringRef v : MinimalConformingFunctions) | ||||||
| 338 | ConformingFunctions.insert(v); | ||||||
| 339 | } else { | ||||||
| 340 | for (StringRef v : POSIXConformingFunctions) | ||||||
| 341 | ConformingFunctions.insert(v); | ||||||
| 342 | } | ||||||
| 343 | } | ||||||
| 344 | |||||||
| 345 | void SignalHandlerCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) { | ||||||
| 346 | Options.store(Opts, "AsyncSafeFunctionSet", AsyncSafeFunctionSet); | ||||||
| 347 | } | ||||||
| 348 | |||||||
| 349 | bool SignalHandlerCheck::isLanguageVersionSupported( | ||||||
| 350 | const LangOptions &LangOpts) const { | ||||||
| 351 | return !LangOpts.CPlusPlus17; | ||||||
| 352 | } | ||||||
| 353 | |||||||
| 354 | void SignalHandlerCheck::registerMatchers(MatchFinder *Finder) { | ||||||
| 355 | auto SignalFunction = functionDecl(hasAnyName("::signal", "::std::signal"), | ||||||
| 356 | parameterCountIs(2), isStandardFunction()); | ||||||
| 357 | auto HandlerExpr = | ||||||
| 358 | declRefExpr(hasDeclaration(functionDecl().bind("handler_decl")), | ||||||
| 359 | unless(isExpandedFromMacro("SIG_IGN")), | ||||||
| 360 | unless(isExpandedFromMacro("SIG_DFL"))) | ||||||
| 361 | .bind("handler_expr"); | ||||||
| 362 | auto HandlerLambda = cxxMemberCallExpr( | ||||||
| 363 | on(expr(ignoringParenImpCasts(lambdaExpr().bind("handler_lambda"))))); | ||||||
| 364 | Finder->addMatcher(callExpr(callee(SignalFunction), | ||||||
| 365 | hasArgument(1, anyOf(HandlerExpr, HandlerLambda))) | ||||||
| 366 | .bind("register_call"), | ||||||
| 367 | this); | ||||||
| 368 | } | ||||||
| 369 | |||||||
| 370 | void SignalHandlerCheck::check(const MatchFinder::MatchResult &Result) { | ||||||
| 371 | if (const auto *HandlerLambda
| ||||||
| |||||||
| 372 | Result.Nodes.getNodeAs<LambdaExpr>("handler_lambda")) { | ||||||
| 373 | diag(HandlerLambda->getBeginLoc(), | ||||||
| 374 | "lambda function is not allowed as signal handler (until C++17)") | ||||||
| 375 | << HandlerLambda->getSourceRange(); | ||||||
| 376 | return; | ||||||
| 377 | } | ||||||
| 378 | |||||||
| 379 | const auto *HandlerDecl = | ||||||
| 380 | Result.Nodes.getNodeAs<FunctionDecl>("handler_decl"); | ||||||
| 381 | const auto *HandlerExpr = Result.Nodes.getNodeAs<DeclRefExpr>("handler_expr"); | ||||||
| 382 | assert(Result.Nodes.getNodeAs<CallExpr>("register_call") && HandlerDecl &&(static_cast <bool> (Result.Nodes.getNodeAs<CallExpr >("register_call") && HandlerDecl && HandlerExpr && "All of these should exist in a match here.") ? void (0) : __assert_fail ("Result.Nodes.getNodeAs<CallExpr>(\"register_call\") && HandlerDecl && HandlerExpr && \"All of these should exist in a match here.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 383, __extension__ __PRETTY_FUNCTION__)) | ||||||
| 383 | HandlerExpr && "All of these should exist in a match here.")(static_cast <bool> (Result.Nodes.getNodeAs<CallExpr >("register_call") && HandlerDecl && HandlerExpr && "All of these should exist in a match here.") ? void (0) : __assert_fail ("Result.Nodes.getNodeAs<CallExpr>(\"register_call\") && HandlerDecl && HandlerExpr && \"All of these should exist in a match here.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 383, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 384 | |||||||
| 385 | if (CG.size() <= 1) { | ||||||
| 386 | // Call graph must be populated with the entire TU at the beginning. | ||||||
| 387 | // (It is possible to add a single function but the functions called from it | ||||||
| 388 | // are not analysed in this case.) | ||||||
| 389 | CG.addToCallGraph(const_cast<TranslationUnitDecl *>( | ||||||
| 390 | HandlerDecl->getTranslationUnitDecl())); | ||||||
| 391 | assert(CG.size() > 1 &&(static_cast <bool> (CG.size() > 1 && "There should be at least one function added to call graph." ) ? void (0) : __assert_fail ("CG.size() > 1 && \"There should be at least one function added to call graph.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 392, __extension__ __PRETTY_FUNCTION__)) | ||||||
| 392 | "There should be at least one function added to call graph.")(static_cast <bool> (CG.size() > 1 && "There should be at least one function added to call graph." ) ? void (0) : __assert_fail ("CG.size() > 1 && \"There should be at least one function added to call graph.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 392, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 393 | } | ||||||
| 394 | |||||||
| 395 | if (!HandlerDecl->hasBody()) { | ||||||
| 396 | // Check the handler function. | ||||||
| 397 | // The warning is placed to the signal handler registration. | ||||||
| 398 | // No need to display a call chain and no need for more checks. | ||||||
| 399 | (void)checkFunction(HandlerDecl, HandlerExpr, {}); | ||||||
| 400 | return; | ||||||
| 401 | } | ||||||
| 402 | |||||||
| 403 | // FIXME: Update CallGraph::getNode to use canonical decl? | ||||||
| 404 | CallGraphNode *HandlerNode = CG.getNode(HandlerDecl->getCanonicalDecl()); | ||||||
| 405 | assert(HandlerNode &&(static_cast <bool> (HandlerNode && "Handler with body should be present in the call graph." ) ? void (0) : __assert_fail ("HandlerNode && \"Handler with body should be present in the call graph.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 406, __extension__ __PRETTY_FUNCTION__)) | ||||||
| 406 | "Handler with body should be present in the call graph.")(static_cast <bool> (HandlerNode && "Handler with body should be present in the call graph." ) ? void (0) : __assert_fail ("HandlerNode && \"Handler with body should be present in the call graph.\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 406, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 407 | // Start from signal handler and visit every function call. | ||||||
| 408 | auto Itr = llvm::df_begin(HandlerNode), ItrE = llvm::df_end(HandlerNode); | ||||||
| 409 | while (Itr != ItrE) { | ||||||
| 410 | const auto *CallF = dyn_cast<FunctionDecl>((*Itr)->getDecl()); | ||||||
| 411 | unsigned int PathL = Itr.getPathLength(); | ||||||
| 412 | if (CallF
| ||||||
| 413 | // A signal handler or a function transitively reachable from the signal | ||||||
| 414 | // handler was found to be unsafe. | ||||||
| 415 | // Generate notes for the whole call chain (including the signal handler | ||||||
| 416 | // registration). | ||||||
| 417 | const Expr *CallOrRef = (PathL > 1) | ||||||
| 418 | ? findCallExpr(Itr.getPath(PathL - 2), *Itr) | ||||||
| 419 | : HandlerExpr; | ||||||
| 420 | auto ChainReporter = [this, &Itr, HandlerExpr](bool SkipPathEnd) { | ||||||
| 421 | reportHandlerChain(Itr, HandlerExpr, SkipPathEnd); | ||||||
| |||||||
| 422 | }; | ||||||
| 423 | // If problems were found in a function (`CallF`), skip the analysis of | ||||||
| 424 | // functions that are called from it. | ||||||
| 425 | if (checkFunction(CallF, CallOrRef, ChainReporter)) | ||||||
| 426 | Itr.skipChildren(); | ||||||
| 427 | else | ||||||
| 428 | ++Itr; | ||||||
| 429 | } else { | ||||||
| 430 | ++Itr; | ||||||
| 431 | } | ||||||
| 432 | } | ||||||
| 433 | } | ||||||
| 434 | |||||||
| 435 | bool SignalHandlerCheck::checkFunction( | ||||||
| 436 | const FunctionDecl *FD, const Expr *CallOrRef, | ||||||
| 437 | std::function<void(bool)> ChainReporter) { | ||||||
| 438 | bool FunctionIsCalled = isa<CallExpr>(CallOrRef); | ||||||
| 439 | |||||||
| 440 | if (isStandardFunction(FD)) { | ||||||
| 441 | if (!isStandardFunctionAsyncSafe(FD)) { | ||||||
| 442 | diag(CallOrRef->getBeginLoc(), "standard function %0 may not be " | ||||||
| 443 | "asynchronous-safe; " | ||||||
| 444 | "%select{using it as|calling it from}1 " | ||||||
| 445 | "a signal handler may be dangerous") | ||||||
| 446 | << FD << FunctionIsCalled << CallOrRef->getSourceRange(); | ||||||
| 447 | if (ChainReporter) | ||||||
| 448 | ChainReporter(/*SkipPathEnd=*/true); | ||||||
| 449 | return true; | ||||||
| 450 | } | ||||||
| 451 | return false; | ||||||
| 452 | } | ||||||
| 453 | |||||||
| 454 | if (!FD->hasBody()) { | ||||||
| 455 | diag(CallOrRef->getBeginLoc(), "cannot verify that external function %0 is " | ||||||
| 456 | "asynchronous-safe; " | ||||||
| 457 | "%select{using it as|calling it from}1 " | ||||||
| 458 | "a signal handler may be dangerous") | ||||||
| 459 | << FD << FunctionIsCalled << CallOrRef->getSourceRange(); | ||||||
| 460 | if (ChainReporter) | ||||||
| 461 | ChainReporter(/*SkipPathEnd=*/true); | ||||||
| 462 | return true; | ||||||
| 463 | } | ||||||
| 464 | |||||||
| 465 | if (getLangOpts().CPlusPlus) | ||||||
| 466 | return checkFunctionCPP14(FD, CallOrRef, ChainReporter); | ||||||
| 467 | |||||||
| 468 | return false; | ||||||
| 469 | } | ||||||
| 470 | |||||||
| 471 | bool SignalHandlerCheck::checkFunctionCPP14( | ||||||
| 472 | const FunctionDecl *FD, const Expr *CallOrRef, | ||||||
| 473 | std::function<void(bool)> ChainReporter) { | ||||||
| 474 | if (!FD->isExternC()) { | ||||||
| 475 | diag(CallOrRef->getBeginLoc(), | ||||||
| 476 | "functions without C linkage are not allowed as signal " | ||||||
| 477 | "handler (until C++17)"); | ||||||
| 478 | if (ChainReporter) | ||||||
| 479 | ChainReporter(/*SkipPathEnd=*/true); | ||||||
| 480 | return true; | ||||||
| 481 | } | ||||||
| 482 | |||||||
| 483 | const FunctionDecl *FBody; | ||||||
| 484 | const Stmt *BodyS = FD->getBody(FBody); | ||||||
| 485 | if (!BodyS) | ||||||
| 486 | return false; | ||||||
| 487 | |||||||
| 488 | bool StmtProblemsFound = false; | ||||||
| 489 | ASTContext &Ctx = FBody->getASTContext(); | ||||||
| 490 | auto Matches = | ||||||
| 491 | match(decl(forEachDescendant(stmt().bind("stmt"))), *FBody, Ctx); | ||||||
| 492 | for (const auto &Match : Matches) { | ||||||
| 493 | const auto *FoundS = Match.getNodeAs<Stmt>("stmt"); | ||||||
| 494 | if (isCXXOnlyStmt(FoundS)) { | ||||||
| 495 | SourceRange R = getSourceRangeOfStmt(FoundS, Ctx); | ||||||
| 496 | if (R.isInvalid()) | ||||||
| 497 | continue; | ||||||
| 498 | diag(R.getBegin(), | ||||||
| 499 | "C++-only construct is not allowed in signal handler (until C++17)") | ||||||
| 500 | << R; | ||||||
| 501 | diag(R.getBegin(), "internally, the statement is parsed as a '%0'", | ||||||
| 502 | DiagnosticIDs::Remark) | ||||||
| 503 | << FoundS->getStmtClassName(); | ||||||
| 504 | if (ChainReporter) | ||||||
| 505 | ChainReporter(/*SkipPathEnd=*/false); | ||||||
| 506 | StmtProblemsFound = true; | ||||||
| 507 | } | ||||||
| 508 | } | ||||||
| 509 | |||||||
| 510 | return StmtProblemsFound; | ||||||
| 511 | } | ||||||
| 512 | |||||||
| 513 | bool SignalHandlerCheck::isStandardFunctionAsyncSafe( | ||||||
| 514 | const FunctionDecl *FD) const { | ||||||
| 515 | assert(isStandardFunction(FD))(static_cast <bool> (isStandardFunction(FD)) ? void (0) : __assert_fail ("isStandardFunction(FD)", "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 515, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 516 | |||||||
| 517 | const IdentifierInfo *II = FD->getIdentifier(); | ||||||
| 518 | // Unnamed functions are not explicitly allowed. | ||||||
| 519 | // C++ std operators may be unsafe and not within the | ||||||
| 520 | // "common subset of C and C++". | ||||||
| 521 | if (!II) | ||||||
| 522 | return false; | ||||||
| 523 | |||||||
| 524 | if (!FD->isInStdNamespace() && !FD->isGlobal()) | ||||||
| 525 | return false; | ||||||
| 526 | |||||||
| 527 | if (ConformingFunctions.count(II->getName())) | ||||||
| 528 | return true; | ||||||
| 529 | |||||||
| 530 | return false; | ||||||
| 531 | } | ||||||
| 532 | |||||||
| 533 | void SignalHandlerCheck::reportHandlerChain( | ||||||
| 534 | const llvm::df_iterator<clang::CallGraphNode *> &Itr, | ||||||
| 535 | const DeclRefExpr *HandlerRef, bool SkipPathEnd) { | ||||||
| 536 | int CallLevel = Itr.getPathLength() - 2; | ||||||
| 537 | assert(CallLevel >= -1 && "Empty iterator?")(static_cast <bool> (CallLevel >= -1 && "Empty iterator?" ) ? void (0) : __assert_fail ("CallLevel >= -1 && \"Empty iterator?\"" , "clang-tools-extra/clang-tidy/bugprone/SignalHandlerCheck.cpp" , 537, __extension__ __PRETTY_FUNCTION__)); | ||||||
| 538 | |||||||
| 539 | const CallGraphNode *Caller = Itr.getPath(CallLevel + 1), *Callee = nullptr; | ||||||
| 540 | while (CallLevel >= 0) { | ||||||
| 541 | Callee = Caller; | ||||||
| 542 | Caller = Itr.getPath(CallLevel); | ||||||
| 543 | const Expr *CE = findCallExpr(Caller, Callee); | ||||||
| 544 | if (SkipPathEnd) | ||||||
| 545 | SkipPathEnd = false; | ||||||
| 546 | else | ||||||
| 547 | diag(CE->getBeginLoc(), "function %0 called here from %1", | ||||||
| 548 | DiagnosticIDs::Note) | ||||||
| 549 | << cast<FunctionDecl>(Callee->getDecl()) | ||||||
| 550 | << cast<FunctionDecl>(Caller->getDecl()); | ||||||
| 551 | --CallLevel; | ||||||
| 552 | } | ||||||
| 553 | |||||||
| 554 | if (!SkipPathEnd) | ||||||
| 555 | diag(HandlerRef->getBeginLoc(), | ||||||
| 556 | "function %0 registered here as signal handler", DiagnosticIDs::Note) | ||||||
| 557 | << cast<FunctionDecl>(Caller->getDecl()) | ||||||
| 558 | << HandlerRef->getSourceRange(); | ||||||
| 559 | } | ||||||
| 560 | |||||||
| 561 | } // namespace bugprone | ||||||
| 562 | } // namespace clang::tidy |
| 1 | // Implementation of std::function -*- C++ -*- |
| 2 | |
| 3 | // Copyright (C) 2004-2020 Free Software Foundation, Inc. |
| 4 | // |
| 5 | // This file is part of the GNU ISO C++ Library. This library is free |
| 6 | // software; you can redistribute it and/or modify it under the |
| 7 | // terms of the GNU General Public License as published by the |
| 8 | // Free Software Foundation; either version 3, or (at your option) |
| 9 | // any later version. |
| 10 | |
| 11 | // This library is distributed in the hope that it will be useful, |
| 12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | // GNU General Public License for more details. |
| 15 | |
| 16 | // Under Section 7 of GPL version 3, you are granted additional |
| 17 | // permissions described in the GCC Runtime Library Exception, version |
| 18 | // 3.1, as published by the Free Software Foundation. |
| 19 | |
| 20 | // You should have received a copy of the GNU General Public License and |
| 21 | // a copy of the GCC Runtime Library Exception along with this program; |
| 22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| 23 | // <http://www.gnu.org/licenses/>. |
| 24 | |
| 25 | /** @file include/bits/std_function.h |
| 26 | * This is an internal header file, included by other library headers. |
| 27 | * Do not attempt to use it directly. @headername{functional} |
| 28 | */ |
| 29 | |
| 30 | #ifndef _GLIBCXX_STD_FUNCTION_H1 |
| 31 | #define _GLIBCXX_STD_FUNCTION_H1 1 |
| 32 | |
| 33 | #pragma GCC system_header |
| 34 | |
| 35 | #if __cplusplus201703L < 201103L |
| 36 | # include <bits/c++0x_warning.h> |
| 37 | #else |
| 38 | |
| 39 | #if __cpp_rtti199711L |
| 40 | # include <typeinfo> |
| 41 | #endif |
| 42 | #include <bits/stl_function.h> |
| 43 | #include <bits/invoke.h> |
| 44 | #include <bits/refwrap.h> |
| 45 | #include <bits/functexcept.h> |
| 46 | |
| 47 | namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default"))) |
| 48 | { |
| 49 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| 50 | |
| 51 | /** |
| 52 | * @brief Exception class thrown when class template function's |
| 53 | * operator() is called with an empty target. |
| 54 | * @ingroup exceptions |
| 55 | */ |
| 56 | class bad_function_call : public std::exception |
| 57 | { |
| 58 | public: |
| 59 | virtual ~bad_function_call() noexcept; |
| 60 | |
| 61 | const char* what() const noexcept; |
| 62 | }; |
| 63 | |
| 64 | /** |
| 65 | * Trait identifying "location-invariant" types, meaning that the |
| 66 | * address of the object (or any of its members) will not escape. |
| 67 | * Trivially copyable types are location-invariant and users can |
| 68 | * specialize this trait for other types. |
| 69 | */ |
| 70 | template<typename _Tp> |
| 71 | struct __is_location_invariant |
| 72 | : is_trivially_copyable<_Tp>::type |
| 73 | { }; |
| 74 | |
| 75 | class _Undefined_class; |
| 76 | |
| 77 | union _Nocopy_types |
| 78 | { |
| 79 | void* _M_object; |
| 80 | const void* _M_const_object; |
| 81 | void (*_M_function_pointer)(); |
| 82 | void (_Undefined_class::*_M_member_pointer)(); |
| 83 | }; |
| 84 | |
| 85 | union [[gnu::may_alias]] _Any_data |
| 86 | { |
| 87 | void* _M_access() { return &_M_pod_data[0]; } |
| 88 | const void* _M_access() const { return &_M_pod_data[0]; } |
| 89 | |
| 90 | template<typename _Tp> |
| 91 | _Tp& |
| 92 | _M_access() |
| 93 | { return *static_cast<_Tp*>(_M_access()); } |
| 94 | |
| 95 | template<typename _Tp> |
| 96 | const _Tp& |
| 97 | _M_access() const |
| 98 | { return *static_cast<const _Tp*>(_M_access()); } |
| 99 | |
| 100 | _Nocopy_types _M_unused; |
| 101 | char _M_pod_data[sizeof(_Nocopy_types)]; |
| 102 | }; |
| 103 | |
| 104 | enum _Manager_operation |
| 105 | { |
| 106 | __get_type_info, |
| 107 | __get_functor_ptr, |
| 108 | __clone_functor, |
| 109 | __destroy_functor |
| 110 | }; |
| 111 | |
| 112 | template<typename _Signature> |
| 113 | class function; |
| 114 | |
| 115 | /// Base class of all polymorphic function object wrappers. |
| 116 | class _Function_base |
| 117 | { |
| 118 | public: |
| 119 | static const size_t _M_max_size = sizeof(_Nocopy_types); |
| 120 | static const size_t _M_max_align = __alignof__(_Nocopy_types); |
| 121 | |
| 122 | template<typename _Functor> |
| 123 | class _Base_manager |
| 124 | { |
| 125 | protected: |
| 126 | static const bool __stored_locally = |
| 127 | (__is_location_invariant<_Functor>::value |
| 128 | && sizeof(_Functor) <= _M_max_size |
| 129 | && __alignof__(_Functor) <= _M_max_align |
| 130 | && (_M_max_align % __alignof__(_Functor) == 0)); |
| 131 | |
| 132 | typedef integral_constant<bool, __stored_locally> _Local_storage; |
| 133 | |
| 134 | // Retrieve a pointer to the function object |
| 135 | static _Functor* |
| 136 | _M_get_pointer(const _Any_data& __source) |
| 137 | { |
| 138 | if _GLIBCXX17_CONSTEXPRconstexpr (__stored_locally) |
| 139 | { |
| 140 | const _Functor& __f = __source._M_access<_Functor>(); |
| 141 | return const_cast<_Functor*>(std::__addressof(__f)); |
| 142 | } |
| 143 | else // have stored a pointer |
| 144 | return __source._M_access<_Functor*>(); |
| 145 | } |
| 146 | |
| 147 | // Clone a location-invariant function object that fits within |
| 148 | // an _Any_data structure. |
| 149 | static void |
| 150 | _M_clone(_Any_data& __dest, const _Any_data& __source, true_type) |
| 151 | { |
| 152 | ::new (__dest._M_access()) _Functor(__source._M_access<_Functor>()); |
| 153 | } |
| 154 | |
| 155 | // Clone a function object that is not location-invariant or |
| 156 | // that cannot fit into an _Any_data structure. |
| 157 | static void |
| 158 | _M_clone(_Any_data& __dest, const _Any_data& __source, false_type) |
| 159 | { |
| 160 | __dest._M_access<_Functor*>() = |
| 161 | new _Functor(*__source._M_access<const _Functor*>()); |
| 162 | } |
| 163 | |
| 164 | // Destroying a location-invariant object may still require |
| 165 | // destruction. |
| 166 | static void |
| 167 | _M_destroy(_Any_data& __victim, true_type) |
| 168 | { |
| 169 | __victim._M_access<_Functor>().~_Functor(); |
| 170 | } |
| 171 | |
| 172 | // Destroying an object located on the heap. |
| 173 | static void |
| 174 | _M_destroy(_Any_data& __victim, false_type) |
| 175 | { |
| 176 | delete __victim._M_access<_Functor*>(); |
| 177 | } |
| 178 | |
| 179 | public: |
| 180 | static bool |
| 181 | _M_manager(_Any_data& __dest, const _Any_data& __source, |
| 182 | _Manager_operation __op) |
| 183 | { |
| 184 | switch (__op) |
| 185 | { |
| 186 | #if __cpp_rtti199711L |
| 187 | case __get_type_info: |
| 188 | __dest._M_access<const type_info*>() = &typeid(_Functor); |
| 189 | break; |
| 190 | #endif |
| 191 | case __get_functor_ptr: |
| 192 | __dest._M_access<_Functor*>() = _M_get_pointer(__source); |
| 193 | break; |
| 194 | |
| 195 | case __clone_functor: |
| 196 | _M_clone(__dest, __source, _Local_storage()); |
| 197 | break; |
| 198 | |
| 199 | case __destroy_functor: |
| 200 | _M_destroy(__dest, _Local_storage()); |
| 201 | break; |
| 202 | } |
| 203 | return false; |
| 204 | } |
| 205 | |
| 206 | static void |
| 207 | _M_init_functor(_Any_data& __functor, _Functor&& __f) |
| 208 | { _M_init_functor(__functor, std::move(__f), _Local_storage()); } |
| 209 | |
| 210 | template<typename _Signature> |
| 211 | static bool |
| 212 | _M_not_empty_function(const function<_Signature>& __f) |
| 213 | { return static_cast<bool>(__f); } |
| 214 | |
| 215 | template<typename _Tp> |
| 216 | static bool |
| 217 | _M_not_empty_function(_Tp* __fp) |
| 218 | { return __fp != nullptr; } |
| 219 | |
| 220 | template<typename _Class, typename _Tp> |
| 221 | static bool |
| 222 | _M_not_empty_function(_Tp _Class::* __mp) |
| 223 | { return __mp != nullptr; } |
| 224 | |
| 225 | template<typename _Tp> |
| 226 | static bool |
| 227 | _M_not_empty_function(const _Tp&) |
| 228 | { return true; } |
| 229 | |
| 230 | private: |
| 231 | static void |
| 232 | _M_init_functor(_Any_data& __functor, _Functor&& __f, true_type) |
| 233 | { ::new (__functor._M_access()) _Functor(std::move(__f)); } |
| 234 | |
| 235 | static void |
| 236 | _M_init_functor(_Any_data& __functor, _Functor&& __f, false_type) |
| 237 | { __functor._M_access<_Functor*>() = new _Functor(std::move(__f)); } |
| 238 | }; |
| 239 | |
| 240 | _Function_base() : _M_manager(nullptr) { } |
| 241 | |
| 242 | ~_Function_base() |
| 243 | { |
| 244 | if (_M_manager) |
| 245 | _M_manager(_M_functor, _M_functor, __destroy_functor); |
| 246 | } |
| 247 | |
| 248 | bool _M_empty() const { return !_M_manager; } |
| 249 | |
| 250 | typedef bool (*_Manager_type)(_Any_data&, const _Any_data&, |
| 251 | _Manager_operation); |
| 252 | |
| 253 | _Any_data _M_functor; |
| 254 | _Manager_type _M_manager; |
| 255 | }; |
| 256 | |
| 257 | template<typename _Signature, typename _Functor> |
| 258 | class _Function_handler; |
| 259 | |
| 260 | template<typename _Res, typename _Functor, typename... _ArgTypes> |
| 261 | class _Function_handler<_Res(_ArgTypes...), _Functor> |
| 262 | : public _Function_base::_Base_manager<_Functor> |
| 263 | { |
| 264 | typedef _Function_base::_Base_manager<_Functor> _Base; |
| 265 | |
| 266 | public: |
| 267 | static bool |
| 268 | _M_manager(_Any_data& __dest, const _Any_data& __source, |
| 269 | _Manager_operation __op) |
| 270 | { |
| 271 | switch (__op) |
| 272 | { |
| 273 | #if __cpp_rtti199711L |
| 274 | case __get_type_info: |
| 275 | __dest._M_access<const type_info*>() = &typeid(_Functor); |
| 276 | break; |
| 277 | #endif |
| 278 | case __get_functor_ptr: |
| 279 | __dest._M_access<_Functor*>() = _Base::_M_get_pointer(__source); |
| 280 | break; |
| 281 | |
| 282 | default: |
| 283 | _Base::_M_manager(__dest, __source, __op); |
| 284 | } |
| 285 | return false; |
| 286 | } |
| 287 | |
| 288 | static _Res |
| 289 | _M_invoke(const _Any_data& __functor, _ArgTypes&&... __args) |
| 290 | { |
| 291 | return std::__invoke_r<_Res>(*_Base::_M_get_pointer(__functor), |
| 292 | std::forward<_ArgTypes>(__args)...); |
| 293 | } |
| 294 | }; |
| 295 | |
| 296 | /** |
| 297 | * @brief Primary class template for std::function. |
| 298 | * @ingroup functors |
| 299 | * |
| 300 | * Polymorphic function wrapper. |
| 301 | */ |
| 302 | template<typename _Res, typename... _ArgTypes> |
| 303 | class function<_Res(_ArgTypes...)> |
| 304 | : public _Maybe_unary_or_binary_function<_Res, _ArgTypes...>, |
| 305 | private _Function_base |
| 306 | { |
| 307 | template<typename _Func, |
| 308 | typename _Res2 = __invoke_result<_Func&, _ArgTypes...>> |
| 309 | struct _Callable |
| 310 | : __is_invocable_impl<_Res2, _Res>::type |
| 311 | { }; |
| 312 | |
| 313 | // Used so the return type convertibility checks aren't done when |
| 314 | // performing overload resolution for copy construction/assignment. |
| 315 | template<typename _Tp> |
| 316 | struct _Callable<function, _Tp> : false_type { }; |
| 317 | |
| 318 | template<typename _Cond, typename _Tp> |
| 319 | using _Requires = typename enable_if<_Cond::value, _Tp>::type; |
| 320 | |
| 321 | public: |
| 322 | typedef _Res result_type; |
| 323 | |
| 324 | // [3.7.2.1] construct/copy/destroy |
| 325 | |
| 326 | /** |
| 327 | * @brief Default construct creates an empty function call wrapper. |
| 328 | * @post @c !(bool)*this |
| 329 | */ |
| 330 | function() noexcept |
| 331 | : _Function_base() { } |
| 332 | |
| 333 | /** |
| 334 | * @brief Creates an empty function call wrapper. |
| 335 | * @post @c !(bool)*this |
| 336 | */ |
| 337 | function(nullptr_t) noexcept |
| 338 | : _Function_base() { } |
| 339 | |
| 340 | /** |
| 341 | * @brief %Function copy constructor. |
| 342 | * @param __x A %function object with identical call signature. |
| 343 | * @post @c bool(*this) == bool(__x) |
| 344 | * |
| 345 | * The newly-created %function contains a copy of the target of @a |
| 346 | * __x (if it has one). |
| 347 | */ |
| 348 | function(const function& __x); |
| 349 | |
| 350 | /** |
| 351 | * @brief %Function move constructor. |
| 352 | * @param __x A %function object rvalue with identical call signature. |
| 353 | * |
| 354 | * The newly-created %function contains the target of @a __x |
| 355 | * (if it has one). |
| 356 | */ |
| 357 | function(function&& __x) noexcept : _Function_base() |
| 358 | { |
| 359 | __x.swap(*this); |
| 360 | } |
| 361 | |
| 362 | /** |
| 363 | * @brief Builds a %function that targets a copy of the incoming |
| 364 | * function object. |
| 365 | * @param __f A %function object that is callable with parameters of |
| 366 | * type @c T1, @c T2, ..., @c TN and returns a value convertible |
| 367 | * to @c Res. |
| 368 | * |
| 369 | * The newly-created %function object will target a copy of |
| 370 | * @a __f. If @a __f is @c reference_wrapper<F>, then this function |
| 371 | * object will contain a reference to the function object @c |
| 372 | * __f.get(). If @a __f is a NULL function pointer or NULL |
| 373 | * pointer-to-member, the newly-created object will be empty. |
| 374 | * |
| 375 | * If @a __f is a non-NULL function pointer or an object of type @c |
| 376 | * reference_wrapper<F>, this function will not throw. |
| 377 | */ |
| 378 | template<typename _Functor, |
| 379 | typename = _Requires<__not_<is_same<_Functor, function>>, void>, |
| 380 | typename = _Requires<_Callable<_Functor>, void>> |
| 381 | function(_Functor); |
| 382 | |
| 383 | /** |
| 384 | * @brief %Function assignment operator. |
| 385 | * @param __x A %function with identical call signature. |
| 386 | * @post @c (bool)*this == (bool)x |
| 387 | * @returns @c *this |
| 388 | * |
| 389 | * The target of @a __x is copied to @c *this. If @a __x has no |
| 390 | * target, then @c *this will be empty. |
| 391 | * |
| 392 | * If @a __x targets a function pointer or a reference to a function |
| 393 | * object, then this operation will not throw an %exception. |
| 394 | */ |
| 395 | function& |
| 396 | operator=(const function& __x) |
| 397 | { |
| 398 | function(__x).swap(*this); |
| 399 | return *this; |
| 400 | } |
| 401 | |
| 402 | /** |
| 403 | * @brief %Function move-assignment operator. |
| 404 | * @param __x A %function rvalue with identical call signature. |
| 405 | * @returns @c *this |
| 406 | * |
| 407 | * The target of @a __x is moved to @c *this. If @a __x has no |
| 408 | * target, then @c *this will be empty. |
| 409 | * |
| 410 | * If @a __x targets a function pointer or a reference to a function |
| 411 | * object, then this operation will not throw an %exception. |
| 412 | */ |
| 413 | function& |
| 414 | operator=(function&& __x) noexcept |
| 415 | { |
| 416 | function(std::move(__x)).swap(*this); |
| 417 | return *this; |
| 418 | } |
| 419 | |
| 420 | /** |
| 421 | * @brief %Function assignment to zero. |
| 422 | * @post @c !(bool)*this |
| 423 | * @returns @c *this |
| 424 | * |
| 425 | * The target of @c *this is deallocated, leaving it empty. |
| 426 | */ |
| 427 | function& |
| 428 | operator=(nullptr_t) noexcept |
| 429 | { |
| 430 | if (_M_manager) |
| 431 | { |
| 432 | _M_manager(_M_functor, _M_functor, __destroy_functor); |
| 433 | _M_manager = nullptr; |
| 434 | _M_invoker = nullptr; |
| 435 | } |
| 436 | return *this; |
| 437 | } |
| 438 | |
| 439 | /** |
| 440 | * @brief %Function assignment to a new target. |
| 441 | * @param __f A %function object that is callable with parameters of |
| 442 | * type @c T1, @c T2, ..., @c TN and returns a value convertible |
| 443 | * to @c Res. |
| 444 | * @return @c *this |
| 445 | * |
| 446 | * This %function object wrapper will target a copy of @a |
| 447 | * __f. If @a __f is @c reference_wrapper<F>, then this function |
| 448 | * object will contain a reference to the function object @c |
| 449 | * __f.get(). If @a __f is a NULL function pointer or NULL |
| 450 | * pointer-to-member, @c this object will be empty. |
| 451 | * |
| 452 | * If @a __f is a non-NULL function pointer or an object of type @c |
| 453 | * reference_wrapper<F>, this function will not throw. |
| 454 | */ |
| 455 | template<typename _Functor> |
| 456 | _Requires<_Callable<typename decay<_Functor>::type>, function&> |
| 457 | operator=(_Functor&& __f) |
| 458 | { |
| 459 | function(std::forward<_Functor>(__f)).swap(*this); |
| 460 | return *this; |
| 461 | } |
| 462 | |
| 463 | /// @overload |
| 464 | template<typename _Functor> |
| 465 | function& |
| 466 | operator=(reference_wrapper<_Functor> __f) noexcept |
| 467 | { |
| 468 | function(__f).swap(*this); |
| 469 | return *this; |
| 470 | } |
| 471 | |
| 472 | // [3.7.2.2] function modifiers |
| 473 | |
| 474 | /** |
| 475 | * @brief Swap the targets of two %function objects. |
| 476 | * @param __x A %function with identical call signature. |
| 477 | * |
| 478 | * Swap the targets of @c this function object and @a __f. This |
| 479 | * function will not throw an %exception. |
| 480 | */ |
| 481 | void swap(function& __x) noexcept |
| 482 | { |
| 483 | std::swap(_M_functor, __x._M_functor); |
| 484 | std::swap(_M_manager, __x._M_manager); |
| 485 | std::swap(_M_invoker, __x._M_invoker); |
| 486 | } |
| 487 | |
| 488 | // [3.7.2.3] function capacity |
| 489 | |
| 490 | /** |
| 491 | * @brief Determine if the %function wrapper has a target. |
| 492 | * |
| 493 | * @return @c true when this %function object contains a target, |
| 494 | * or @c false when it is empty. |
| 495 | * |
| 496 | * This function will not throw an %exception. |
| 497 | */ |
| 498 | explicit operator bool() const noexcept |
| 499 | { return !_M_empty(); } |
| 500 | |
| 501 | // [3.7.2.4] function invocation |
| 502 | |
| 503 | /** |
| 504 | * @brief Invokes the function targeted by @c *this. |
| 505 | * @returns the result of the target. |
| 506 | * @throws bad_function_call when @c !(bool)*this |
| 507 | * |
| 508 | * The function call operator invokes the target function object |
| 509 | * stored by @c this. |
| 510 | */ |
| 511 | _Res operator()(_ArgTypes... __args) const; |
| 512 | |
| 513 | #if __cpp_rtti199711L |
| 514 | // [3.7.2.5] function target access |
| 515 | /** |
| 516 | * @brief Determine the type of the target of this function object |
| 517 | * wrapper. |
| 518 | * |
| 519 | * @returns the type identifier of the target function object, or |
| 520 | * @c typeid(void) if @c !(bool)*this. |
| 521 | * |
| 522 | * This function will not throw an %exception. |
| 523 | */ |
| 524 | const type_info& target_type() const noexcept; |
| 525 | |
| 526 | /** |
| 527 | * @brief Access the stored target function object. |
| 528 | * |
| 529 | * @return Returns a pointer to the stored target function object, |
| 530 | * if @c typeid(_Functor).equals(target_type()); otherwise, a NULL |
| 531 | * pointer. |
| 532 | * |
| 533 | * This function does not throw exceptions. |
| 534 | * |
| 535 | * @{ |
| 536 | */ |
| 537 | template<typename _Functor> _Functor* target() noexcept; |
| 538 | |
| 539 | template<typename _Functor> const _Functor* target() const noexcept; |
| 540 | // @} |
| 541 | #endif |
| 542 | |
| 543 | private: |
| 544 | using _Invoker_type = _Res (*)(const _Any_data&, _ArgTypes&&...); |
| 545 | _Invoker_type _M_invoker; |
| 546 | }; |
| 547 | |
| 548 | #if __cpp_deduction_guides201703L >= 201606 |
| 549 | template<typename> |
| 550 | struct __function_guide_helper |
| 551 | { }; |
| 552 | |
| 553 | template<typename _Res, typename _Tp, bool _Nx, typename... _Args> |
| 554 | struct __function_guide_helper< |
| 555 | _Res (_Tp::*) (_Args...) noexcept(_Nx) |
| 556 | > |
| 557 | { using type = _Res(_Args...); }; |
| 558 | |
| 559 | template<typename _Res, typename _Tp, bool _Nx, typename... _Args> |
| 560 | struct __function_guide_helper< |
| 561 | _Res (_Tp::*) (_Args...) & noexcept(_Nx) |
| 562 | > |
| 563 | { using type = _Res(_Args...); }; |
| 564 | |
| 565 | template<typename _Res, typename _Tp, bool _Nx, typename... _Args> |
| 566 | struct __function_guide_helper< |
| 567 | _Res (_Tp::*) (_Args...) const noexcept(_Nx) |
| 568 | > |
| 569 | { using type = _Res(_Args...); }; |
| 570 | |
| 571 | template<typename _Res, typename _Tp, bool _Nx, typename... _Args> |
| 572 | struct __function_guide_helper< |
| 573 | _Res (_Tp::*) (_Args...) const & noexcept(_Nx) |
| 574 | > |
| 575 | { using type = _Res(_Args...); }; |
| 576 | |
| 577 | template<typename _Res, typename... _ArgTypes> |
| 578 | function(_Res(*)(_ArgTypes...)) -> function<_Res(_ArgTypes...)>; |
| 579 | |
| 580 | template<typename _Functor, typename _Signature = typename |
| 581 | __function_guide_helper<decltype(&_Functor::operator())>::type> |
| 582 | function(_Functor) -> function<_Signature>; |
| 583 | #endif |
| 584 | |
| 585 | // Out-of-line member definitions. |
| 586 | template<typename _Res, typename... _ArgTypes> |
| 587 | function<_Res(_ArgTypes...)>:: |
| 588 | function(const function& __x) |
| 589 | : _Function_base() |
| 590 | { |
| 591 | if (static_cast<bool>(__x)) |
| 592 | { |
| 593 | __x._M_manager(_M_functor, __x._M_functor, __clone_functor); |
| 594 | _M_invoker = __x._M_invoker; |
| 595 | _M_manager = __x._M_manager; |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | template<typename _Res, typename... _ArgTypes> |
| 600 | template<typename _Functor, typename, typename> |
| 601 | function<_Res(_ArgTypes...)>:: |
| 602 | function(_Functor __f) |
| 603 | : _Function_base() |
| 604 | { |
| 605 | typedef _Function_handler<_Res(_ArgTypes...), _Functor> _My_handler; |
| 606 | |
| 607 | if (_My_handler::_M_not_empty_function(__f)) |
| 608 | { |
| 609 | _My_handler::_M_init_functor(_M_functor, std::move(__f)); |
| 610 | _M_invoker = &_My_handler::_M_invoke; |
| 611 | _M_manager = &_My_handler::_M_manager; |
| 612 | } |
| 613 | } |
| 614 | |
| 615 | template<typename _Res, typename... _ArgTypes> |
| 616 | _Res |
| 617 | function<_Res(_ArgTypes...)>:: |
| 618 | operator()(_ArgTypes... __args) const |
| 619 | { |
| 620 | if (_M_empty()) |
| 621 | __throw_bad_function_call(); |
| 622 | return _M_invoker(_M_functor, std::forward<_ArgTypes>(__args)...); |
| 623 | } |
| 624 | |
| 625 | #if __cpp_rtti199711L |
| 626 | template<typename _Res, typename... _ArgTypes> |
| 627 | const type_info& |
| 628 | function<_Res(_ArgTypes...)>:: |
| 629 | target_type() const noexcept |
| 630 | { |
| 631 | if (_M_manager) |
| 632 | { |
| 633 | _Any_data __typeinfo_result; |
| 634 | _M_manager(__typeinfo_result, _M_functor, __get_type_info); |
| 635 | return *__typeinfo_result._M_access<const type_info*>(); |
| 636 | } |
| 637 | else |
| 638 | return typeid(void); |
| 639 | } |
| 640 | |
| 641 | template<typename _Res, typename... _ArgTypes> |
| 642 | template<typename _Functor> |
| 643 | _Functor* |
| 644 | function<_Res(_ArgTypes...)>:: |
| 645 | target() noexcept |
| 646 | { |
| 647 | const function* __const_this = this; |
| 648 | const _Functor* __func = __const_this->template target<_Functor>(); |
| 649 | return const_cast<_Functor*>(__func); |
| 650 | } |
| 651 | |
| 652 | template<typename _Res, typename... _ArgTypes> |
| 653 | template<typename _Functor> |
| 654 | const _Functor* |
| 655 | function<_Res(_ArgTypes...)>:: |
| 656 | target() const noexcept |
| 657 | { |
| 658 | if (typeid(_Functor) == target_type() && _M_manager) |
| 659 | { |
| 660 | _Any_data __ptr; |
| 661 | _M_manager(__ptr, _M_functor, __get_functor_ptr); |
| 662 | return __ptr._M_access<const _Functor*>(); |
| 663 | } |
| 664 | else |
| 665 | return nullptr; |
| 666 | } |
| 667 | #endif |
| 668 | |
| 669 | // [20.7.15.2.6] null pointer comparisons |
| 670 | |
| 671 | /** |
| 672 | * @brief Compares a polymorphic function object wrapper against 0 |
| 673 | * (the NULL pointer). |
| 674 | * @returns @c true if the wrapper has no target, @c false otherwise |
| 675 | * |
| 676 | * This function will not throw an %exception. |
| 677 | */ |
| 678 | template<typename _Res, typename... _Args> |
| 679 | inline bool |
| 680 | operator==(const function<_Res(_Args...)>& __f, nullptr_t) noexcept |
| 681 | { return !static_cast<bool>(__f); } |
| 682 | |
| 683 | #if __cpp_impl_three_way_comparison < 201907L |
| 684 | /// @overload |
| 685 | template<typename _Res, typename... _Args> |
| 686 | inline bool |
| 687 | operator==(nullptr_t, const function<_Res(_Args...)>& __f) noexcept |
| 688 | { return !static_cast<bool>(__f); } |
| 689 | |
| 690 | /** |
| 691 | * @brief Compares a polymorphic function object wrapper against 0 |
| 692 | * (the NULL pointer). |
| 693 | * @returns @c false if the wrapper has no target, @c true otherwise |
| 694 | * |
| 695 | * This function will not throw an %exception. |
| 696 | */ |
| 697 | template<typename _Res, typename... _Args> |
| 698 | inline bool |
| 699 | operator!=(const function<_Res(_Args...)>& __f, nullptr_t) noexcept |
| 700 | { return static_cast<bool>(__f); } |
| 701 | |
| 702 | /// @overload |
| 703 | template<typename _Res, typename... _Args> |
| 704 | inline bool |
| 705 | operator!=(nullptr_t, const function<_Res(_Args...)>& __f) noexcept |
| 706 | { return static_cast<bool>(__f); } |
| 707 | #endif |
| 708 | |
| 709 | // [20.7.15.2.7] specialized algorithms |
| 710 | |
| 711 | /** |
| 712 | * @brief Swap the targets of two polymorphic function object wrappers. |
| 713 | * |
| 714 | * This function will not throw an %exception. |
| 715 | */ |
| 716 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| 717 | // 2062. Effect contradictions w/o no-throw guarantee of std::function swaps |
| 718 | template<typename _Res, typename... _Args> |
| 719 | inline void |
| 720 | swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y) noexcept |
| 721 | { __x.swap(__y); } |
| 722 | |
| 723 | #if __cplusplus201703L >= 201703L |
| 724 | namespace __detail::__variant |
| 725 | { |
| 726 | template<typename> struct _Never_valueless_alt; // see <variant> |
| 727 | |
| 728 | // Provide the strong exception-safety guarantee when emplacing a |
| 729 | // function into a variant. |
| 730 | template<typename _Signature> |
| 731 | struct _Never_valueless_alt<std::function<_Signature>> |
| 732 | : std::true_type |
| 733 | { }; |
| 734 | } // namespace __detail::__variant |
| 735 | #endif // C++17 |
| 736 | |
| 737 | _GLIBCXX_END_NAMESPACE_VERSION |
| 738 | } // namespace std |
| 739 | |
| 740 | #endif // C++11 |
| 741 | #endif // _GLIBCXX_STD_FUNCTION_H |
| 1 | // Implementation of INVOKE -*- C++ -*- | ||||||
| 2 | |||||||
| 3 | // Copyright (C) 2016-2020 Free Software Foundation, Inc. | ||||||
| 4 | // | ||||||
| 5 | // This file is part of the GNU ISO C++ Library. This library is free | ||||||
| 6 | // software; you can redistribute it and/or modify it under the | ||||||
| 7 | // terms of the GNU General Public License as published by the | ||||||
| 8 | // Free Software Foundation; either version 3, or (at your option) | ||||||
| 9 | // any later version. | ||||||
| 10 | |||||||
| 11 | // This library is distributed in the hope that it will be useful, | ||||||
| 12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of | ||||||
| 13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||||||
| 14 | // GNU General Public License for more details. | ||||||
| 15 | |||||||
| 16 | // Under Section 7 of GPL version 3, you are granted additional | ||||||
| 17 | // permissions described in the GCC Runtime Library Exception, version | ||||||
| 18 | // 3.1, as published by the Free Software Foundation. | ||||||
| 19 | |||||||
| 20 | // You should have received a copy of the GNU General Public License and | ||||||
| 21 | // a copy of the GCC Runtime Library Exception along with this program; | ||||||
| 22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see | ||||||
| 23 | // <http://www.gnu.org/licenses/>. | ||||||
| 24 | |||||||
| 25 | /** @file include/bits/invoke.h | ||||||
| 26 | * This is an internal header file, included by other library headers. | ||||||
| 27 | * Do not attempt to use it directly. @headername{functional} | ||||||
| 28 | */ | ||||||
| 29 | |||||||
| 30 | #ifndef _GLIBCXX_INVOKE_H1 | ||||||
| 31 | #define _GLIBCXX_INVOKE_H1 1 | ||||||
| 32 | |||||||
| 33 | #pragma GCC system_header | ||||||
| 34 | |||||||
| 35 | #if __cplusplus201703L < 201103L | ||||||
| 36 | # include <bits/c++0x_warning.h> | ||||||
| 37 | #else | ||||||
| 38 | |||||||
| 39 | #include <type_traits> | ||||||
| 40 | |||||||
| 41 | namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default"))) | ||||||
| 42 | { | ||||||
| 43 | _GLIBCXX_BEGIN_NAMESPACE_VERSION | ||||||
| 44 | |||||||
| 45 | /** | ||||||
| 46 | * @addtogroup utilities | ||||||
| 47 | * @{ | ||||||
| 48 | */ | ||||||
| 49 | |||||||
| 50 | // Used by __invoke_impl instead of std::forward<_Tp> so that a | ||||||
| 51 | // reference_wrapper is converted to an lvalue-reference. | ||||||
| 52 | template<typename _Tp, typename _Up = typename __inv_unwrap<_Tp>::type> | ||||||
| 53 | constexpr _Up&& | ||||||
| 54 | __invfwd(typename remove_reference<_Tp>::type& __t) noexcept | ||||||
| 55 | { return static_cast<_Up&&>(__t); } | ||||||
| 56 | |||||||
| 57 | template<typename _Res, typename _Fn, typename... _Args> | ||||||
| 58 | constexpr _Res | ||||||
| 59 | __invoke_impl(__invoke_other, _Fn&& __f, _Args&&... __args) | ||||||
| 60 | { return std::forward<_Fn>(__f)(std::forward<_Args>(__args)...); } | ||||||
| 61 | |||||||
| 62 | template<typename _Res, typename _MemFun, typename _Tp, typename... _Args> | ||||||
| 63 | constexpr _Res | ||||||
| 64 | __invoke_impl(__invoke_memfun_ref, _MemFun&& __f, _Tp&& __t, | ||||||
| 65 | _Args&&... __args) | ||||||
| 66 | { return (__invfwd<_Tp>(__t).*__f)(std::forward<_Args>(__args)...); } | ||||||
| 67 | |||||||
| 68 | template<typename _Res, typename _MemFun, typename _Tp, typename... _Args> | ||||||
| 69 | constexpr _Res | ||||||
| 70 | __invoke_impl(__invoke_memfun_deref, _MemFun&& __f, _Tp&& __t, | ||||||
| 71 | _Args&&... __args) | ||||||
| 72 | { | ||||||
| 73 | return ((*std::forward<_Tp>(__t)).*__f)(std::forward<_Args>(__args)...); | ||||||
| 74 | } | ||||||
| 75 | |||||||
| 76 | template<typename _Res, typename _MemPtr, typename _Tp> | ||||||
| 77 | constexpr _Res | ||||||
| 78 | __invoke_impl(__invoke_memobj_ref, _MemPtr&& __f, _Tp&& __t) | ||||||
| 79 | { return __invfwd<_Tp>(__t).*__f; } | ||||||
| 80 | |||||||
| 81 | template<typename _Res, typename _MemPtr, typename _Tp> | ||||||
| 82 | constexpr _Res | ||||||
| 83 | __invoke_impl(__invoke_memobj_deref, _MemPtr&& __f, _Tp&& __t) | ||||||
| 84 | { return (*std::forward<_Tp>(__t)).*__f; } | ||||||
| 85 | |||||||
| 86 | /// Invoke a callable object. | ||||||
| 87 | template<typename _Callable, typename... _Args> | ||||||
| 88 | constexpr typename __invoke_result<_Callable, _Args...>::type | ||||||
| 89 | __invoke(_Callable&& __fn, _Args&&... __args) | ||||||
| 90 | noexcept(__is_nothrow_invocable<_Callable, _Args...>::value) | ||||||
| 91 | { | ||||||
| 92 | using __result = __invoke_result<_Callable, _Args...>; | ||||||
| 93 | using __type = typename __result::type; | ||||||
| 94 | using __tag = typename __result::__invoke_type; | ||||||
| 95 | return std::__invoke_impl<__type>(__tag{}, std::forward<_Callable>(__fn), | ||||||
| 96 | std::forward<_Args>(__args)...); | ||||||
| 97 | } | ||||||
| 98 | |||||||
| 99 | #if __cplusplus201703L >= 201703L | ||||||
| 100 | // INVOKE<R>: Invoke a callable object and convert the result to R. | ||||||
| 101 | template<typename _Res, typename _Callable, typename... _Args> | ||||||
| 102 | constexpr enable_if_t<is_invocable_r_v<_Res, _Callable, _Args...>, _Res> | ||||||
| 103 | __invoke_r(_Callable&& __fn, _Args&&... __args) | ||||||
| 104 | noexcept(is_nothrow_invocable_r_v<_Res, _Callable, _Args...>) | ||||||
| 105 | { | ||||||
| 106 | using __result = __invoke_result<_Callable, _Args...>; | ||||||
| 107 | using __type = typename __result::type; | ||||||
| 108 | using __tag = typename __result::__invoke_type; | ||||||
| 109 | if constexpr (is_void_v<_Res>
| ||||||
| 110 | std::__invoke_impl<__type>(__tag{}, std::forward<_Callable>(__fn), | ||||||
| 111 | std::forward<_Args>(__args)...); | ||||||
| 112 | else | ||||||
| 113 | return std::__invoke_impl<__type>(__tag{}, | ||||||
| 114 | std::forward<_Callable>(__fn), | ||||||
| 115 | std::forward<_Args>(__args)...); | ||||||
| 116 | } | ||||||
| 117 | #else // C++11 | ||||||
| 118 | template<typename _Res, typename _Callable, typename... _Args> | ||||||
| 119 | using __can_invoke_as_void = __enable_if_t< | ||||||
| 120 | __and_<is_void<_Res>, __is_invocable<_Callable, _Args...>>::value, | ||||||
| 121 | _Res | ||||||
| 122 | >; | ||||||
| 123 | |||||||
| 124 | template<typename _Res, typename _Callable, typename... _Args> | ||||||
| 125 | using __can_invoke_as_nonvoid = __enable_if_t< | ||||||
| 126 | __and_<__not_<is_void<_Res>>, | ||||||
| 127 | is_convertible<typename __invoke_result<_Callable, _Args...>::type, | ||||||
| 128 | _Res> | ||||||
| 129 | >::value, | ||||||
| 130 | _Res | ||||||
| 131 | >; | ||||||
| 132 | |||||||
| 133 | // INVOKE<R>: Invoke a callable object and convert the result to R. | ||||||
| 134 | template<typename _Res, typename _Callable, typename... _Args> | ||||||
| 135 | constexpr __can_invoke_as_nonvoid<_Res, _Callable, _Args...> | ||||||
| 136 | __invoke_r(_Callable&& __fn, _Args&&... __args) | ||||||
| 137 | { | ||||||
| 138 | using __result = __invoke_result<_Callable, _Args...>; | ||||||
| 139 | using __type = typename __result::type; | ||||||
| 140 | using __tag = typename __result::__invoke_type; | ||||||
| 141 | return std::__invoke_impl<__type>(__tag{}, std::forward<_Callable>(__fn), | ||||||
| 142 | std::forward<_Args>(__args)...); | ||||||
| 143 | } | ||||||
| 144 | |||||||
| 145 | // INVOKE<R> when R is cv void | ||||||
| 146 | template<typename _Res, typename _Callable, typename... _Args> | ||||||
| 147 | _GLIBCXX14_CONSTEXPRconstexpr __can_invoke_as_void<_Res, _Callable, _Args...> | ||||||
| 148 | __invoke_r(_Callable&& __fn, _Args&&... __args) | ||||||
| 149 | { | ||||||
| 150 | using __result = __invoke_result<_Callable, _Args...>; | ||||||
| 151 | using __type = typename __result::type; | ||||||
| 152 | using __tag = typename __result::__invoke_type; | ||||||
| 153 | std::__invoke_impl<__type>(__tag{}, std::forward<_Callable>(__fn), | ||||||
| 154 | std::forward<_Args>(__args)...); | ||||||
| 155 | } | ||||||
| 156 | #endif // C++11 | ||||||
| 157 | |||||||
| 158 | _GLIBCXX_END_NAMESPACE_VERSION | ||||||
| 159 | } // namespace std | ||||||
| 160 | |||||||
| 161 | #endif // C++11 | ||||||
| 162 | |||||||
| 163 | #endif // _GLIBCXX_INVOKE_H |