1 /*
2    Copyright (c) 2013, 2021, Oracle and/or its affiliates.
3 
4    This program is free software; you can redistribute it and/or modify
5    it under the terms of the GNU General Public License, version 2.0,
6    as published by the Free Software Foundation.
7 
8    This program is also distributed with certain software (including
9    but not limited to OpenSSL) that is licensed under separate terms,
10    as designated in a particular file or component or in included license
11    documentation.  The authors of MySQL hereby grant you an additional
12    permission to link the program and your derivative works with the
13    separately licensed software that they have included with MySQL.
14 
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License, version 2.0, for more details.
19 
20    You should have received a copy of the GNU General Public License
21    along with this program; if not, write to the Free Software
22    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
23 */
24 
25 #ifndef SQL_CHANNEL_INFO_INCLUDED
26 #define SQL_CHANNEL_INFO_INCLUDED
27 
28 #include "my_global.h"         // uint
29 #include "my_sys.h"            // my_micro_time
30 
31 class THD;
32 typedef struct st_vio Vio;
33 
34 
35 /**
36   This abstract base class represents connection channel information
37   about a new connection. Its subclasses encapsulate differences
38   between different connection channel types.
39 
40   Currently we support local and TCP/IP sockets (all platforms),
41   named pipes and shared memory (Windows only).
42 */
43 class Channel_info
44 {
45   ulonglong prior_thr_create_utime;
46 
47 protected:
48   /**
49     Create and initialize a Vio object.
50 
51     @retval   return a pointer to the initialized a vio object.
52   */
53   virtual Vio* create_and_init_vio() const = 0;
54 
Channel_info()55   Channel_info()
56   : prior_thr_create_utime(0)
57   { }
58 
59 public:
~Channel_info()60   virtual ~Channel_info() {}
61 
62   /**
63     Instantiate and initialize THD object and vio.
64 
65     @return
66       @retval
67         THD* pointer to initialized THD object.
68       @retval
69         NULL THD object allocation fails.
70   */
71   virtual THD* create_thd() = 0;
72 
73   /**
74     Send error back to the client and close the channel.
75 
76     @param errorcode   code indicating type of error.
77     @param error       operating system specific error code.
78     @param senderror   true if the error need to be sent to
79                        client else false.
80   */
81   virtual void send_error_and_close_channel(uint errorcode,
82                                             int error,
83                                             bool senderror) = 0;
84 
get_prior_thr_create_utime()85   ulonglong get_prior_thr_create_utime() const
86   { return prior_thr_create_utime; }
87 
set_prior_thr_create_utime()88   void set_prior_thr_create_utime()
89   { prior_thr_create_utime= my_micro_time(); }
90 };
91 
92 #endif // SQL_CHANNEL_INFO_INCLUDED.
93