Fixed #4189 (Improve check (printf('%l') not detected))

lib/checkio.cpp

@@ -560,6 +560,35 @@ void CheckIO::checkWrongPrintfScanfArguments()
                                 else if (argListTok->type() == Token::eString)
                                     invalidPrintfArgTypeError_float(tok, numFormat, *i);
                                 break;
+                            case 'h': // Can be 'hh' (signed char or unsigned char) or 'h' (short int or unsigned short int)
+                            case 'l': // Can be 'll' (long long int or unsigned long long int) or 'l' (long int or unsigned long int)
+                                // If the next character is the same (which makes 'hh' or 'll') then expect another alphabetical character
+                                if (i != formatString.end() && *(i+1) == *i) {
+                                    if (i+1 != formatString.end() && !isalpha(*(i+2))) {
+                                        std::string modifier;
+                                        modifier += *i;
+                                        modifier += *(i+1);
+                                        invalidLengthModifierError(tok, numFormat, modifier);
+                                    }
+                                } else {
+                                    if (i != formatString.end() && !isalpha(*(i+1))) {
+                                        std::string modifier;
+                                        modifier += *i;
+                                        invalidLengthModifierError(tok, numFormat, modifier);
+                                    }
+                                }
+                                break;
+                            case 'j': // intmax_t or uintmax_t
+                            case 'z': // size_t
+                            case 't': // ptrdiff_t
+                            case 'L': // long double
+                                // Expect an alphabetical character after these specifiers
+                                if (i != formatString.end() && !isalpha(*(i+1))) {
+                                    std::string modifier;
+                                    modifier += *i;
+                                    invalidLengthModifierError(tok, numFormat, modifier);
+                                }
+                                break;
                             default:
                                 break;
                             }
@@ -654,6 +683,13 @@ void CheckIO::invalidPrintfArgTypeError_float(const Token* tok, unsigned int num
     errmsg << "%" << c << " in format string (no. " << numFormat << ") requires a floating point number given in the argument list.";
     reportError(tok, Severity::warning, "invalidPrintfArgType_float", errmsg.str());
 }
+void CheckIO::invalidLengthModifierError(const Token* tok, unsigned int numFormat, std::string& modifier)
+{
+    std::ostringstream errmsg;
+    errmsg << "'" << modifier << "' in format string (no. " << numFormat << ") is a length modifier and cannot be used without a conversion specifier.";
+    reportError(tok, Severity::warning, "invalidLengthModifierError", errmsg.str());
+}
+
 void CheckIO::invalidScanfFormatWidthError(const Token* tok, unsigned int numFormat, int width, const Variable *var)
 {
     std::ostringstream errmsg;

lib/checkio.h

@@ -90,6 +90,7 @@ private:
     void invalidPrintfArgTypeError_uint(const Token* tok, unsigned int numFormat, char c);
     void invalidPrintfArgTypeError_sint(const Token* tok, unsigned int numFormat, char c);
     void invalidPrintfArgTypeError_float(const Token* tok, unsigned int numFormat, char c);
+    void invalidLengthModifierError(const Token* tok, unsigned int numFormat, std::string& modifier);
     void invalidScanfFormatWidthError(const Token* tok, unsigned int numFormat, int width, const Variable *var);
 
     void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const {

test/testio.cpp

@@ -640,6 +640,48 @@ private:
         TODO_ASSERT_EQUALS("[test.cpp:3]: (warning) %u in format string (no. 1) requires an integer given in the argument list.\n"
                            "[test.cpp:4]: (warning) %f in format string (no. 1) requires an integer given in the argument list.\n"
                            "[test.cpp:5]: (warning) %p in format string (no. 1) requires an integer given in the argument list.\n", "", errout.str());
+
+        // Ticket #4189 (Improve check (printf("%l") not detected)) tests (according to C99 7.19.6.1.7)
+        // False positive tests
+        check("void foo(signed char sc, unsigned char uc, short int si, unsigned short int usi) {\n"
+              "  printf(\"%hhx %hhd\", sc, uc);\n"
+              "  printf(\"%hd %hi\", si, usi);\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+
+        check("void foo(long long int lli, unsigned long long int ulli, long int li, unsigned long int uli) {\n"
+              "  printf(\"%llo %llx\", lli, ulli);\n"
+              "  printf(\"%ld %lu\", li, uli);\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+
+        check("void foo(intmax_t im, uintmax_t uim, size_t s, ptrdiff_t p, long double ld) {\n"
+              "  printf(\"%jd %jo\", im, uim);\n"
+              "  printf(\"%zx\", s);\n"
+              "  printf(\"%ti\", p);\n"
+              "  printf(\"%La\", ld);\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
+
+        // False negative test
+        check("void foo(unsigned int i) {\n"
+              "  printf(\"%h\", i);\n"
+              "  printf(\"%hh\", i);\n"
+              "  printf(\"%l\", i);\n"
+              "  printf(\"%ll\", i);\n"
+              "  printf(\"%j\", i);\n"
+              "  printf(\"%z\", i);\n"
+              "  printf(\"%t\", i);\n"
+              "  printf(\"%L\", i);\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (warning) 'h' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:3]: (warning) 'hh' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:4]: (warning) 'l' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:5]: (warning) 'll' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:6]: (warning) 'j' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:7]: (warning) 'z' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:8]: (warning) 't' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n"
+                      "[test.cpp:9]: (warning) 'L' in format string (no. 1) is a length modifier and cannot be used without a conversion specifier.\n", errout.str());
     }
 };