From 565ac2fca665ff30dd142b77781d78bb8a96875e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <hyd_danmar@users.sourceforge.net>
Date: Thu, 23 Jul 2009 16:30:30 +0200
Subject: [PATCH] Fixed #493 (Memory leak: False positive when using the
 exit(0))

---
 src/checkmemoryleak.cpp | 56 +++++++++++++++++++----------------------
 test/testmemleak.cpp    | 30 ++++++++++++++++++++++
 2 files changed, 56 insertions(+), 30 deletions(-)

diff --git a/src/checkmemoryleak.cpp b/src/checkmemoryleak.cpp
index 7b962f917..55912ad08 100644
--- a/src/checkmemoryleak.cpp
+++ b/src/checkmemoryleak.cpp
@@ -895,7 +895,10 @@ Token *CheckMemoryLeakInFunction::getcode(const Token *tok, std::list<const Toke
 
         // exit..
         if (Token::Match(tok->previous(), "[{};] exit ( %any% ) ;"))
+        {
             addtoken("exit");
+            tok = tok->tokAt(3);
+        }
 
         // Assignment..
         if (Token::Match(tok, std::string("[)=] " + varnameStr + " [+;)]").c_str()) ||
@@ -1006,36 +1009,6 @@ void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
             tok2->str("return");
     }
 
-
-    // simplify "exit".. remove everything in its execution path
-    for (Token *tok2 = tok; tok2; tok2 = tok2->next())
-    {
-        if (tok2->str() != "exit")
-            continue;
-
-        // Found an "exit".. try to remove everything before it
-        Token *tokEnd = tok2->next();
-        int indentlevel = 0;
-        while (tok2->previous())
-        {
-            tok2 = tok2->previous();
-            if (tok2->str() == "}")
-            {
-                indentlevel--;
-            }
-            else if (tok2->str() == "{")
-            {
-                if (indentlevel == 0)
-                    break;
-
-                indentlevel++;
-            }
-        }
-
-        Token::eraseTokens(tok2, tokEnd);
-        tok2 = tokEnd;
-    }
-
     // If "--all" is given, remove all "callfunc"..
     if (_settings->_showAll)
     {
@@ -1257,6 +1230,27 @@ void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
                 done = false;
             }
 
+            // Reduce "alloc|dealloc|use ; exit ;" => "; exit ;"
+            if (Token::Match(tok2, "alloc|dealloc|use ; exit ;"))
+            {
+                tok2->deleteThis();
+                done = false;
+            }
+
+            // Reduce "alloc|dealloc|use ; if(var) exit ;"
+            if (Token::Match(tok2, "alloc|dealloc|use ; if(var) exit ;"))
+            {
+                tok2->deleteThis();
+                done = false;
+            }
+
+            // Remove "if exit ;"
+            if (Token::simpleMatch(tok2, "if exit ;"))
+            {
+                tok2->deleteThis();
+                tok2->deleteThis();
+                done = false;
+            }
 
             // Replace "dealloc use ;" with "dealloc ;"
             if (Token::simpleMatch(tok2, "dealloc use ;"))
@@ -1485,6 +1479,8 @@ void CheckMemoryLeakInFunction::simplifycode(Token *tok, bool &all)
             }
         }
     }
+
+
 }
 
 
diff --git a/test/testmemleak.cpp b/test/testmemleak.cpp
index f8f0f9299..48ef0079a 100644
--- a/test/testmemleak.cpp
+++ b/test/testmemleak.cpp
@@ -265,6 +265,8 @@ private:
         // Using the function "exit"
         TEST_CASE(exit1);
         TEST_CASE(exit2);
+        TEST_CASE(exit3);
+        TEST_CASE(exit4);
         TEST_CASE(stdstring);
 
         TEST_CASE(strndup_function);
@@ -2118,6 +2120,34 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void exit3()
+    {
+        check("void f()\n"
+              "{\n"
+              "    char *p = malloc(100);\n"
+              "    if (p)\n"
+              "    {\n"
+              "        exit(0);\n"
+              "    }\n"
+              "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
+    void exit4()
+    {
+        check("void f()\n"
+              "{\n"
+              "    char *p = malloc(100);\n"
+              "    if (x)\n"
+              "    {\n"
+              "        exit(0);\n"
+              "    }\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:8]: (error) Memory leak: p\n", errout.str());
+    }
+
+
+
     void stdstring()
     {
         check("void f(std::string foo)\n"