posix.cfg: Improved configuration for close(). Issue a warning in case close is called with a file pointer having a negative value.

cfg/posix.cfg

@@ -1114,9 +1114,10 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
   <function name="close">
     <noreturn>false</noreturn>
     <returnValue type="int"/>
-    <arg nr="1">
+    <arg nr="1" direction="in">
       <not-uninit/>
       <not-bool/>
+      <valid>0:</valid>
     </arg>
   </function>
   <!-- size_t confstr(int, char *, size_t); -->

test/cfg/posix.c

@@ -215,6 +215,14 @@ void invalidFunctionArg()
     usleep(1000000);
 }
 
+void invalidFunctionArg_close(int fd)
+{
+    if (fd < 0) {
+        // cppcheck-suppress invalidFunctionArg
+        (void)close(fd);
+    }
+}
+
 void uninitvar(int fd)
 {
     int x1, x2, x3, x4;