posix.cfg: Improved configuration for 'mkstemp()' and added test cases to ensure resource leaks are caught.

cfg/posix.cfg

@@ -825,7 +825,6 @@ The obsolescent function 'usleep' is called. POSIX.1-2001 declares usleep() func
   <!-- int mkstemp(char *template); -->
   <function name="mkstemp">
     <noreturn>false</noreturn>
-    <leak-ignore/>
     <returnValue type="int"/>
     <arg nr="1">
       <not-null/>
@@ -4583,6 +4582,7 @@ The function 'mktemp' is considered to be dangerous due to race conditions and s
   </memory>
   <resource>
     <alloc init="true">open</alloc>
+    <alloc init="true">mkstemp</alloc>
     <alloc init="true">creat</alloc>
     <alloc init="true">openat</alloc>
     <alloc init="true">socket</alloc>

test/cfg/posix.c

@@ -134,6 +134,24 @@ void resourceLeak_fdopen(int fd)
     // cppcheck-suppress resourceLeak
 }
 
+void resourceLeak_mkstemp(char *template)
+{
+	// cppcheck-suppress unreadVariable
+	int fp = mkstemp(template);
+	// cppcheck-suppress resourceLeak
+}
+
+void no_resourceLeak_mkstemp_01(char *template)
+{
+	int fp = mkstemp(template);
+	close(fp);
+}
+
+int no_resourceLeak_mkstemp_02(char *template)
+{
+	return mkstemp(template);
+}
+
 void resourceLeak_fdopendir(int fd)
 {
     // cppcheck-suppress unreadVariable