Fixed bug #2310 "INET_ATON handles short-forms addresses incorrectly"

mysql-test/r/func_misc.result:
  added new test for inet_aton (short-forms addresses)
mysql-test/t/func_misc.test:
  added new test for inet_aton (short-forms addresses)
sql/item_func.cc:
  Change Item_func_inet_aton::val_int to parse short-forms addresses correctly

mysql-test/r/func_misc.result

@@ -6,10 +6,19 @@ inet_ntoa(inet_aton("255.255.255.255.255.255.255.255"))
 NULL
 select inet_aton("255.255.255.255.255"),inet_aton("255.255.1.255"),inet_aton("0.1.255");
 inet_aton("255.255.255.255.255")	inet_aton("255.255.1.255")	inet_aton("0.1.255")
-1099511627775	4294902271	511
+1099511627775	4294902271	65791
 select inet_ntoa(1099511627775),inet_ntoa(4294902271),inet_ntoa(511);
 inet_ntoa(1099511627775)	inet_ntoa(4294902271)	inet_ntoa(511)
 NULL	255.255.1.255	0.0.1.255
+select hex(inet_aton('127'));
+hex(inet_aton('127'))
+7F
+select hex(inet_aton('127.1'));
+hex(inet_aton('127.1'))
+7F000001
+select hex(inet_aton('127.1.1'));
+hex(inet_aton('127.1.1'))
+7F010001
 select length(format('nan', 2)) > 0;
 length(format('nan', 2)) > 0
 1

mysql-test/t/func_misc.test

@@ -8,6 +8,10 @@ select inet_ntoa(inet_aton("255.255.255.255.255.255.255.255"));
 select inet_aton("255.255.255.255.255"),inet_aton("255.255.1.255"),inet_aton("0.1.255");
 select inet_ntoa(1099511627775),inet_ntoa(4294902271),inet_ntoa(511);
 
+select hex(inet_aton('127'));
+select hex(inet_aton('127.1'));
+select hex(inet_aton('127.1.1'));
+
 #
 # Test for core dump with nan
 #

sql/item_func.cc

@@ -2618,6 +2618,7 @@ longlong Item_func_inet_aton::val_int()
   const char *p,* end;
   char c = '.'; // we mark c to indicate invalid IP in case length is 0
   char buff[36];
+  int dot_count= 0;
 
   String *s,tmp(buff,sizeof(buff),&my_charset_bin);
   if (!(s = args[0]->val_str(&tmp)))		// If null value
@@ -2636,6 +2637,7 @@ longlong Item_func_inet_aton::val_int()
     }
     else if (c == '.')
     {
+      dot_count++;
       result= (result << 8) + (ulonglong) byte_result;
       byte_result = 0;
     }
@@ -2643,7 +2645,14 @@ longlong Item_func_inet_aton::val_int()
       goto err;					// Invalid character
   }
   if (c != '.')					// IP number can't end on '.'
+  {
+    switch (dot_count)
+    {
+    case 1: result<<= 8;
+    case 2: result<<= 8;
+    }
     return (result << 8) + (ulonglong) byte_result;
+  }
 
 err:
   null_value=1;