Tokenizer: simplify loops that continue while errno is EINTR

lib/tokenize.cpp

@@ -3598,6 +3598,7 @@ bool Tokenizer::simplifyTokenList()
     simplifyComparisonOrder();
     simplifyNestedStrcat();
     simplifyWhile0();
+    simplifyErrNoInWhile();
     simplifyFuncInWhile();
 
     simplifyIfAssign();    // could be affected by simplifyIfNot
@@ -7480,6 +7481,38 @@ void Tokenizer::simplifyWhile0()
     }
 }
 
+void Tokenizer::simplifyErrNoInWhile()
+{
+    for (Token *tok = _tokens; tok; tok = tok->next())
+    {
+        if (tok->str() != "errno")
+            continue;
+
+        Token *endpar = 0;
+        if (Token::Match(tok->previous(), "&& errno == EINTR ) { ;| }"))
+            endpar = tok->tokAt(3);
+        else if (Token::Match(tok->tokAt(-2), "&& ( errno == EINTR ) ) { ;| }"))
+            endpar = tok->tokAt(4);
+        else
+            continue;
+
+        if (Token::simpleMatch(endpar->link()->previous(), "while ("))
+        {
+            Token *tok1 = tok->previous();
+            if (tok1->str() == "(")
+                tok1 = tok1->previous();
+
+            // erase "&& errno == EINTR"
+            Token::eraseTokens(tok1->previous(), endpar);
+
+            // tok is invalid.. move to endpar
+            tok = endpar;
+
+        }
+    }
+}
+
+
 void Tokenizer::simplifyFuncInWhile()
 {
     for (Token *tok = _tokens; tok; tok = tok->next())

lib/tokenize.h

@@ -366,6 +366,11 @@ public:
      */
     void simplifyWhile0();
 
+    /**
+     * Simplify while(func() && errno==EINTR)
+     */
+    void simplifyErrNoInWhile();
+
     /**
      * Simplify while(func(f))
      */

test/testsimplifytokens.cpp

@@ -243,6 +243,9 @@ private:
         // x = realloc(y,0);  =>  free(y);x=0;
         TEST_CASE(simplifyRealloc);
 
+        // while(f() && errno==EINTR) { } => while (f()) { }
+        TEST_CASE(simplifyErrNoInWhile);
+
         // while(fclose(f)); => r = fclose(f); while(r){r=fclose(f);}
         TEST_CASE(simplifyFuncInWhile);
 
@@ -4938,6 +4941,14 @@ private:
                       tok("; p = realloc(p,0);"));
     }
 
+    void simplifyErrNoInWhile()
+    {
+        ASSERT_EQUALS("; while ( f ( ) ) { }",
+                      tok("; while (f() && errno == EINTR) { }"));
+        ASSERT_EQUALS("; while ( f ( ) ) { }",
+                      tok("; while (f() && (errno == EINTR)) { }"));
+    }
+
     void simplifyFuncInWhile()
     {
         ASSERT_EQUALS("int cppcheck:r = fclose ( f ) ; "