Fix ticket #312 (division by pointer value causes wrong tokenizing)

http://apps.sourceforge.net/trac/cppcheck/ticket/312

src/preprocessor.cpp

@@ -81,7 +81,7 @@ std::string Preprocessor::read(std::istream &istr)
         // Skip spaces after ' ' and after '#'
         if (ch == ' ' && ignoreSpace)
             continue;
-        ignoreSpace = bool(ch == ' ' || ch == '#' || ch == '/' || ch == '\n');
+        ignoreSpace = bool(ch == ' ' || ch == '#' || ch == '\n');
 
         if (needSpace)
         {
@@ -148,8 +148,8 @@ std::string Preprocessor::removeComments(const std::string &str)
     // when this is encountered the <backspace><newline> will be "skipped".
     // on the next <newline>, extra newlines will be added
     unsigned int newlines = 0;
-
     std::ostringstream code;
+    char previous = 0;
     for (std::string::size_type i = 0; i < str.length(); ++i)
     {
         char ch = str[i];
@@ -157,25 +157,20 @@ std::string Preprocessor::removeComments(const std::string &str)
             throw std::runtime_error("The code contains characters that are unhandled");
 
         // Remove comments..
-        if (ch == '/')
+        if (str.compare(i, 2, "//", 0, 2) == 0)
         {
-            ++i;
-            char chNext = str[i];
+            i = str.find('\n', i);
+            if (i == std::string::npos)
+                break;
 
-            if (chNext == '/')
-            {
-                while (i < str.length() && ch != '\n')
-                {
-                    ++i;
-                    ch = str[i];
-                }
             code << "\n";
+            previous = '\n';
             ++lineno;
         }
-
-            else if (chNext == '*')
+        else if (str.compare(i, 2, "/*", 0, 2) == 0)
         {
             char chPrev = 0;
+            ++i;
             while (i < str.length() && (chPrev != '*' || ch != '/'))
             {
                 chPrev = ch;
@@ -184,19 +179,12 @@ std::string Preprocessor::removeComments(const std::string &str)
                 if (ch == '\n')
                 {
                     code << "\n";
+                    previous = '\n';
                     ++lineno;
                 }
             }
         }
 
-            else
-            {
-                if (chNext == '\n')
-                    ++lineno;
-                code << std::string(1, ch) << std::string(1, chNext);
-            }
-        }
-
         // String or char constants..
         else if (ch == '\"' || ch == '\'')
         {
@@ -216,10 +204,14 @@ std::string Preprocessor::removeComments(const std::string &str)
                     {
                         code << std::string(1, chNext);
                         code << std::string(1, chSeq);
+                        previous = chSeq;
                     }
                 }
                 else
+                {
                     code << std::string(1, chNext);
+                    previous = chNext;
+                }
             }
             while (i < str.length() && chNext != ch);
         }
@@ -227,14 +219,24 @@ std::string Preprocessor::removeComments(const std::string &str)
 
         // Just some code..
         else
+        {
+            if (ch == ' ' && previous == ' ')
+            {
+                // Skip double white space
+            }
+            else
             {
                 code << std::string(1, ch);
+                previous = ch;
+            }
+
 
             // if there has been <backspace><newline> sequences, add extra newlines..
             if (ch == '\n' && newlines > 0)
             {
                 code << std::string(newlines, '\n');
                 newlines = 0;
+                previous = '\n';
             }
         }
     }

test/testpreprocessor.cpp

@@ -417,6 +417,23 @@ private:
             ASSERT_EQUALS("\n\n\n\n", actual[""]);
             ASSERT_EQUALS(1, static_cast<unsigned int>(actual.size()));
         }
+
+        {
+            const char filedata[] = "void f()\n"
+                                    "{\n"
+                                    "  *p = a / *b / *c;\n"
+                                    "}\n";
+
+            // Preprocess => actual result..
+            std::istringstream istr(filedata);
+            std::map<std::string, std::string> actual;
+            Preprocessor preprocessor;
+            preprocessor.preprocess(istr, actual, "file.c");
+
+            // Compare results..
+            ASSERT_EQUALS("void f()\n{\n*p = a / *b / *c;\n}\n", actual[""]);
+            ASSERT_EQUALS(1, static_cast<unsigned int>(actual.size()));
+        }
     }