[clang-tidy] add ctime and localtime to clang-tidy

clang-tools-extra/clang-tidy/bugprone/UnsafeFunctionsCheck.cpp

@@ -50,6 +50,8 @@ static StringRef getReplacementFor(StringRef FunctionName,
     StringRef AnnexKReplacementFunction =
         StringSwitch<StringRef>(FunctionName)
             .Cases("asctime", "asctime_r", "asctime_s")
+            .Cases("ctime", "ctime_r")
+            .Cases("localtime", "localtime_r")
             .Case("gets", "gets_s")
             .Default({});
     if (!AnnexKReplacementFunction.empty())
@@ -60,6 +62,8 @@ static StringRef getReplacementFor(StringRef FunctionName,
   // should be matched and suggested.
   return StringSwitch<StringRef>(FunctionName)
       .Cases("asctime", "asctime_r", "strftime")
+      .Cases("ctime", "ctime_r")
+      .Cases("localtime", "localtime_r")
       .Case("gets", "fgets")
       .Case("rewind", "fseek")
       .Case("setbuf", "setvbuf");
@@ -90,8 +94,8 @@ static StringRef getReplacementForAdditional(StringRef FunctionName,
 /// safer alternative.
 static StringRef getRationaleFor(StringRef FunctionName) {
   return StringSwitch<StringRef>(FunctionName)
-      .Cases("asctime", "asctime_r", "ctime",
-             "is not bounds-checking and non-reentrant")
+      .Cases("asctime", "asctime_r", "ctime", "ctime_r", "localtime",
+             "localtime_r", "is not bounds-checking and non-reentrant")
       .Cases("bcmp", "bcopy", "bzero", "is deprecated")
       .Cases("fopen", "freopen", "has no exclusive access to the opened file")
       .Case("gets", "is insecure, was deprecated and removed in C11 and C++14")
@@ -223,8 +227,9 @@ void UnsafeFunctionsCheck::registerMatchers(MatchFinder *Finder) {
     }
 
     // Matching functions with replacements without Annex K.
-    auto FunctionNamesMatcher =
-        hasAnyName("::asctime", "asctime_r", "::gets", "::rewind", "::setbuf");
+    auto FunctionNamesMatcher = hasAnyName(
+        "::asctime", "asctime_r", "::ctime", "ctime_r", "::localtime",
+        "localtime_r", "::gets", "::rewind", "::setbuf");
     Finder->addMatcher(
         declRefExpr(
             to(functionDecl(FunctionNamesMatcher).bind(FunctionNamesId)))

clang-tools-extra/docs/ReleaseNotes.rst

@@ -152,7 +152,8 @@ Changes in existing checks
 
 - Improved :doc:`bugprone-unsafe-functions
   <clang-tidy/checks/bugprone/unsafe-functions>` check to allow specifying
-  additional C++ member functions to match.
+  additional C++ member functions to match and by adding ``ctime`` and
+  ``localtime`` to unsafe functions list.
 
 - Improved :doc:`cert-err33-c
   <clang-tidy/checks/cert/err33-c>` check by fixing false positives when

clang-tools-extra/docs/clang-tidy/checks/bugprone/unsafe-functions.rst

@@ -34,7 +34,8 @@ following functions:
 ``vsnprintf``, ``vsprintf``, ``vsscanf``, ``vswprintf``, ``vswscanf``,
 ``vwprintf``, ``vwscanf``, ``wcrtomb``, ``wcscat``, ``wcscpy``,
 ``wcslen``, ``wcsncat``, ``wcsncpy``, ``wcsrtombs``, ``wcstok``, ``wcstombs``,
-``wctomb``, ``wmemcpy``, ``wmemmove``, ``wprintf``, ``wscanf``.
+``wctomb``, ``wmemcpy``, ``wmemmove``, ``wprintf``, ``wscanf``. ``ctime_r``,
+``localtime_r``
 
 If *Annex K.* is not available, replacements are suggested only for the
 following functions from the previous list:

clang-tools-extra/test/clang-tidy/checkers/bugprone/unsafe-functions.c

@@ -108,8 +108,6 @@ char *ctime(const time_t *Timer);
 
 void f4(const time_t *Timer) {
   ctime(Timer);
-  // CHECK-MESSAGES-WITH-ANNEX-K:           :[[@LINE-1]]:3: warning: function 'ctime' is not bounds-checking and non-reentrant; 'ctime_s' should be used instead
-  // CHECK-MESSAGES-WITH-ANNEX-K-CERT-ONLY: :[[@LINE-2]]:3: warning: function 'ctime' is not bounds-checking and non-reentrant; 'ctime_s' should be used instead
   // no-warning WITHOUT-ANNEX-K
 }
 
@@ -157,7 +155,7 @@ typedef size_t rsize_t;
 errno_t asctime_s(char *S, rsize_t Maxsize, const struct tm *TimePtr);
 errno_t strcat_s(char *S1, rsize_t S1Max, const char *S2);
 
-void fUsingSafeFunctions(const struct tm *Time, FILE *F) {
+void fUsingSafeFunctions(const struct tm *Time, FILE *F, time_t *Timep) {
   char Buf[BUFSIZ] = {0};
 
   // no-warning, safe function from annex K is used

clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp

@@ -3533,15 +3533,14 @@ void StdLibraryFunctionsChecker::initFunctionSummaries(
         Signature(ArgTypes{ConstTime_tPtrTy}, RetType{StructTmPtrTy}),
         Summary(NoEvalCall).ArgConstraint(NotNull(ArgNo(0))));
 
-    // struct tm *localtime_r(const time_t *restrict timer,
-    //                        struct tm *restrict result);
-    addToFunctionSummaryMap(
-        "localtime_r",
-        Signature(ArgTypes{ConstTime_tPtrRestrictTy, StructTmPtrRestrictTy},
-                  RetType{StructTmPtrTy}),
-        Summary(NoEvalCall)
-            .ArgConstraint(NotNull(ArgNo(0)))
-            .ArgConstraint(NotNull(ArgNo(1))));
+    // struct tm *localtime_r(const time_t *timer,
+    //                        struct tm *result);
+    addToFunctionSummaryMap("localtime_r",
+                            Signature(ArgTypes{ConstTime_tPtrTy, StructTmPtrTy},
+                                      RetType{StructTmPtrTy}),
+                            Summary(NoEvalCall)
+                                .ArgConstraint(NotNull(ArgNo(0)))
+                                .ArgConstraint(NotNull(ArgNo(1))));
 
     // char *asctime_r(const struct tm *restrict tm, char *restrict buf);
     addToFunctionSummaryMap(

clang/lib/StaticAnalyzer/Checkers/cert/InvalidPtrChecker.cpp

@@ -76,6 +76,10 @@ class InvalidPtrChecker
        &InvalidPtrChecker::postPreviousReturnInvalidatingCall},
       {{CDM::CLibrary, {"asctime"}, 1},
        &InvalidPtrChecker::postPreviousReturnInvalidatingCall},
+      {{CDM::CLibrary, {"ctime"}, 1},
+       &InvalidPtrChecker::postPreviousReturnInvalidatingCall},
+      {{CDM::CLibrary, {"localtime"}, 1},
+       &InvalidPtrChecker::postPreviousReturnInvalidatingCall},
   };
 
   // The private members of this checker corresponding to commandline options

clang/lib/Tooling/Inclusions/Stdlib/StdSymbolMap.inc

@@ -2032,8 +2032,8 @@ SYMBOL(locale, std::, <locale>)
 SYMBOL(localeconv, std::, <clocale>)
 SYMBOL(localeconv, None, <clocale>)
 SYMBOL(localeconv, None, <locale.h>)
-SYMBOL(localtime, std::, <ctime>)
-SYMBOL(localtime, None, <ctime>)
+SYMBOL(localtime, std::, <localtime>)
+SYMBOL(localtime, None, <localtime>)
 SYMBOL(localtime, None, <time.h>)
 SYMBOL(lock, std::, <mutex>)
 SYMBOL(lock_guard, std::, <mutex>)

clang/test/Analysis/Inputs/std-c-library-functions-POSIX.h

@@ -174,7 +174,7 @@ int utimensat(int dirfd, const char *pathname, const struct timespec times[2], i
 int utimes(const char *filename, const struct timeval times[2]);
 int nanosleep(const struct timespec *rqtp, struct timespec *rmtp);
 struct tm *localtime(const time_t *tp);
-struct tm *localtime_r(const time_t *restrict timer, struct tm *restrict result);
+struct tm *localtime_r(const time_t *timer, struct tm *result);
 char *asctime_r(const struct tm *restrict tm, char *restrict buf);
 char *ctime_r(const time_t *timep, char *buf);
 struct tm *gmtime_r(const time_t *restrict timer, struct tm *restrict result);

clang/test/Analysis/cert/env34-c.c

@@ -16,6 +16,8 @@ lconv *localeconv(void);
 typedef struct {
 } tm;
 char *asctime(const tm *timeptr);
+char *ctime(const time_t *time);
+struct tm *localtime(const time_t *time);
 
 int strcmp(const char*, const char*);
 extern void foo(char *e);
@@ -313,6 +315,34 @@ void asctime_test(void) {
   // expected-note@-2{{dereferencing an invalid pointer}}
 }
 
+void ctime_test(void) {
+  const time_t *t;
+  const time_t *tt;
+
+  char* p = ctime(t);
+  // expected-note@-1{{previous function call was here}}
+  char* pp = ctime(tt);
+  // expected-note@-1{{'ctime' call may invalidate the result of the previous 'ctime'}}
+
+  *p;
+  // expected-warning@-1{{dereferencing an invalid pointer}}
+  // expected-note@-2{{dereferencing an invalid pointer}}
+}
+
+void localtime_test(void) {
+  const time_t *t;
+  const time_t *tt;
+
+  struct tm* p = localtime(t);
+  // expected-note@-1{{previous function call was here}}
+  struct tm* pp = localtime(tt);
+  // expected-note@-1{{'localtime' call may invalidate the result of the previous 'localtime'}}
+
+  *p;
+  // expected-warning@-1{{dereferencing an invalid pointer}}
+  // expected-note@-2{{dereferencing an invalid pointer}}
+}
+
 void localeconv_test1(void) {
   lconv *lc1 = localeconv();
   // expected-note@-1{{previous function call was here}}

clang/test/Analysis/std-c-library-functions-POSIX.c

@@ -129,7 +129,7 @@
 // CHECK: Loaded summary for: int utimes(const char *filename, const struct timeval times[2])
 // CHECK: Loaded summary for: int nanosleep(const struct timespec *rqtp, struct timespec *rmtp)
 // CHECK: Loaded summary for: struct tm *localtime(const time_t *tp)
-// CHECK: Loaded summary for: struct tm *localtime_r(const time_t *restrict timer, struct tm *restrict result)
+// CHECK: Loaded summary for: struct tm *localtime_r(const time_t *timer, struct tm *result)
 // CHECK: Loaded summary for: char *asctime_r(const struct tm *restrict tm, char *restrict buf)
 // CHECK: Loaded summary for: char *ctime_r(const time_t *timep, char *buf)
 // CHECK: Loaded summary for: struct tm *gmtime_r(const time_t *restrict timer, struct tm *restrict result)