1 /* Copyright (c) 2008, 2014, Oracle and/or its affiliates. All rights reserved.
2 
3   This program is free software; you can redistribute it and/or modify
4   it under the terms of the GNU General Public License, version 2.0,
5   as published by the Free Software Foundation.
6 
7   This program is also distributed with certain software (including
8   but not limited to OpenSSL) that is licensed under separate terms,
9   as designated in a particular file or component or in included license
10   documentation.  The authors of MySQL hereby grant you an additional
11   permission to link the program and your derivative works with the
12   separately licensed software that they have included with MySQL.
13 
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License, version 2.0, for more details.
18 
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software Foundation,
21   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */
22 
23 #include "my_global.h"
24 #include "my_pthread.h"
25 #include "table_threads.h"
26 #include "sql_parse.h"
27 #include "pfs_instr_class.h"
28 #include "pfs_instr.h"
29 
30 THR_LOCK table_threads::m_table_lock;
31 
32 static const TABLE_FIELD_TYPE field_types[]=
33 {
34   {
35     { C_STRING_WITH_LEN("THREAD_ID") },
36     { C_STRING_WITH_LEN("bigint(20)") },
37     { NULL, 0}
38   },
39   {
40     { C_STRING_WITH_LEN("NAME") },
41     { C_STRING_WITH_LEN("varchar(128)") },
42     { NULL, 0}
43   },
44   {
45     { C_STRING_WITH_LEN("TYPE") },
46     { C_STRING_WITH_LEN("varchar(10)") },
47     { NULL, 0}
48   },
49   {
50     { C_STRING_WITH_LEN("PROCESSLIST_ID") },
51     { C_STRING_WITH_LEN("bigint(20)") },
52     { NULL, 0}
53   },
54   {
55     { C_STRING_WITH_LEN("PROCESSLIST_USER") },
56     { C_STRING_WITH_LEN("varchar(16)") },
57     { NULL, 0}
58   },
59   {
60     { C_STRING_WITH_LEN("PROCESSLIST_HOST") },
61     { C_STRING_WITH_LEN("varchar(60)") },
62     { NULL, 0}
63   },
64   {
65     { C_STRING_WITH_LEN("PROCESSLIST_DB") },
66     { C_STRING_WITH_LEN("varchar(64)") },
67     { NULL, 0}
68   },
69   {
70     { C_STRING_WITH_LEN("PROCESSLIST_COMMAND") },
71     { C_STRING_WITH_LEN("varchar(16)") },
72     { NULL, 0}
73   },
74   {
75     { C_STRING_WITH_LEN("PROCESSLIST_TIME") },
76     { C_STRING_WITH_LEN("bigint(20)") },
77     { NULL, 0}
78   },
79   {
80     { C_STRING_WITH_LEN("PROCESSLIST_STATE") },
81     { C_STRING_WITH_LEN("varchar(64)") },
82     { NULL, 0}
83   },
84   {
85     { C_STRING_WITH_LEN("PROCESSLIST_INFO") },
86     { C_STRING_WITH_LEN("longtext") },
87     { NULL, 0}
88   },
89   {
90     { C_STRING_WITH_LEN("PARENT_THREAD_ID") },
91     { C_STRING_WITH_LEN("bigint(20)") },
92     { NULL, 0}
93   },
94   {
95     { C_STRING_WITH_LEN("ROLE") },
96     { C_STRING_WITH_LEN("varchar(64)") },
97     { NULL, 0}
98   },
99   {
100     { C_STRING_WITH_LEN("INSTRUMENTED") },
101     { C_STRING_WITH_LEN("enum(\'YES\',\'NO\')") },
102     { NULL, 0}
103   }
104 };
105 
106 TABLE_FIELD_DEF
107 table_threads::m_field_def=
108 { 14, field_types };
109 
110 PFS_engine_table_share
111 table_threads::m_share=
112 {
113   { C_STRING_WITH_LEN("threads") },
114   &pfs_updatable_acl,
115   &table_threads::create,
116   NULL, /* write_row */
117   NULL, /* delete_all_rows */
118   NULL, /* get_row_count */
119   1000, /* records */
120   sizeof(PFS_simple_index), /* ref length */
121   &m_table_lock,
122   &m_field_def,
123   false /* checked */
124 };
125 
create()126 PFS_engine_table* table_threads::create()
127 {
128   return new table_threads();
129 }
130 
table_threads()131 table_threads::table_threads()
132   : cursor_by_thread(& m_share),
133   m_row_exists(false)
134 {}
135 
make_row(PFS_thread * pfs)136 void table_threads::make_row(PFS_thread *pfs)
137 {
138   pfs_lock lock;
139   pfs_lock session_lock;
140   pfs_lock stmt_lock;
141   PFS_stage_class *stage_class;
142   PFS_thread_class *safe_class;
143 
144   m_row_exists= false;
145 
146   /* Protect this reader against thread termination */
147   pfs->m_lock.begin_optimistic_lock(&lock);
148 
149   safe_class= sanitize_thread_class(pfs->m_class);
150   if (unlikely(safe_class == NULL))
151     return;
152 
153   m_row.m_thread_internal_id= pfs->m_thread_internal_id;
154   m_row.m_parent_thread_internal_id= pfs->m_parent_thread_internal_id;
155   m_row.m_processlist_id= pfs->m_processlist_id;
156   m_row.m_name= safe_class->m_name;
157   m_row.m_name_length= safe_class->m_name_length;
158 
159   /* Protect this reader against session attribute changes */
160   pfs->m_session_lock.begin_optimistic_lock(&session_lock);
161 
162   m_row.m_username_length= pfs->m_username_length;
163   if (unlikely(m_row.m_username_length > sizeof(m_row.m_username)))
164     return;
165   if (m_row.m_username_length != 0)
166     memcpy(m_row.m_username, pfs->m_username, m_row.m_username_length);
167 
168   m_row.m_hostname_length= pfs->m_hostname_length;
169   if (unlikely(m_row.m_hostname_length > sizeof(m_row.m_hostname)))
170     return;
171   if (m_row.m_hostname_length != 0)
172     memcpy(m_row.m_hostname, pfs->m_hostname, m_row.m_hostname_length);
173 
174   if (! pfs->m_session_lock.end_optimistic_lock(& session_lock))
175   {
176     /*
177       One of the columns:
178       - PROCESSLIST_USER
179       - PROCESSLIST_HOST
180       is being updated.
181       Do not discard the entire row.
182       Do not loop waiting for a stable value.
183       Just return NULL values.
184     */
185     m_row.m_username_length= 0;
186     m_row.m_hostname_length= 0;
187   }
188 
189   /* Protect this reader against statement attributes changes */
190   pfs->m_stmt_lock.begin_optimistic_lock(&stmt_lock);
191 
192   m_row.m_dbname_length= pfs->m_dbname_length;
193   if (unlikely(m_row.m_dbname_length > sizeof(m_row.m_dbname)))
194     return;
195   if (m_row.m_dbname_length != 0)
196     memcpy(m_row.m_dbname, pfs->m_dbname, m_row.m_dbname_length);
197 
198   m_row.m_processlist_info_ptr= & pfs->m_processlist_info[0];
199   m_row.m_processlist_info_length= pfs->m_processlist_info_length;
200 
201   if (! pfs->m_stmt_lock.end_optimistic_lock(& stmt_lock))
202   {
203     /*
204       One of the columns:
205       - PROCESSLIST_DB
206       - PROCESSLIST_INFO
207       is being updated.
208       Do not discard the entire row.
209       Do not loop waiting for a stable value.
210       Just return NULL values.
211     */
212     m_row.m_dbname_length= 0;
213     m_row.m_processlist_info_length= 0;
214   }
215 
216   /* Dirty read, sanitize the command. */
217   m_row.m_command= pfs->m_command;
218   if ((m_row.m_command < 0) || (m_row.m_command > COM_END))
219     m_row.m_command= COM_END;
220 
221   m_row.m_start_time= pfs->m_start_time;
222 
223   stage_class= find_stage_class(pfs->m_stage);
224   if (stage_class != NULL)
225   {
226     m_row.m_processlist_state_ptr= stage_class->m_name + stage_class->m_prefix_length;
227     m_row.m_processlist_state_length= stage_class->m_name_length - stage_class->m_prefix_length;
228   }
229   else
230   {
231     m_row.m_processlist_state_length= 0;
232   }
233 
234   m_row.m_enabled_ptr= pfs->m_disable_instrumentation ? NULL : &pfs->m_enabled;
235 
236   if (pfs->m_lock.end_optimistic_lock(& lock))
237     m_row_exists= true;
238 
239   if(pfs->m_disable_instrumentation)
240     m_row_exists= false;
241 }
242 
read_row_values(TABLE * table,unsigned char * buf,Field ** fields,bool read_all)243 int table_threads::read_row_values(TABLE *table,
244                                    unsigned char *buf,
245                                    Field **fields,
246                                    bool read_all)
247 {
248   Field *f;
249 
250   if (unlikely(! m_row_exists))
251     return HA_ERR_RECORD_DELETED;
252 
253   /* Set the null bits */
254   DBUG_ASSERT(table->s->null_bytes == 2);
255   buf[0]= 0;
256   buf[1]= 0;
257 
258   for (; (f= *fields) ; fields++)
259   {
260     if (read_all || bitmap_is_set(table->read_set, f->field_index))
261     {
262       switch(f->field_index)
263       {
264       case 0: /* THREAD_ID */
265         set_field_ulonglong(f, m_row.m_thread_internal_id);
266         break;
267       case 1: /* NAME */
268         set_field_varchar_utf8(f, m_row.m_name, m_row.m_name_length);
269         break;
270       case 2: /* TYPE */
271         if (m_row.m_processlist_id != 0)
272           set_field_varchar_utf8(f, "FOREGROUND", 10);
273         else
274           set_field_varchar_utf8(f, "BACKGROUND", 10);
275         break;
276       case 3: /* PROCESSLIST_ID */
277         if (m_row.m_processlist_id != 0)
278           set_field_ulonglong(f, m_row.m_processlist_id);
279         else
280           f->set_null();
281         break;
282       case 4: /* PROCESSLIST_USER */
283         if (m_row.m_username_length > 0)
284           set_field_varchar_utf8(f, m_row.m_username,
285                                  m_row.m_username_length);
286         else
287           f->set_null();
288         break;
289       case 5: /* PROCESSLIST_HOST */
290         if (m_row.m_hostname_length > 0)
291           set_field_varchar_utf8(f, m_row.m_hostname,
292                                  m_row.m_hostname_length);
293         else
294           f->set_null();
295         break;
296       case 6: /* PROCESSLIST_DB */
297         if (m_row.m_dbname_length > 0)
298           set_field_varchar_utf8(f, m_row.m_dbname,
299                                  m_row.m_dbname_length);
300         else
301           f->set_null();
302         break;
303       case 7: /* PROCESSLIST_COMMAND */
304         if (m_row.m_processlist_id != 0)
305           set_field_varchar_utf8(f, command_name[m_row.m_command].str,
306                                  command_name[m_row.m_command].length);
307         else
308           f->set_null();
309         break;
310       case 8: /* PROCESSLIST_TIME */
311         if (m_row.m_start_time)
312         {
313           time_t now= my_time(0);
314           ulonglong elapsed= (now > m_row.m_start_time ? now - m_row.m_start_time : 0);
315           set_field_ulonglong(f, elapsed);
316         }
317         else
318           f->set_null();
319         break;
320       case 9: /* PROCESSLIST_STATE */
321         if (m_row.m_processlist_state_length > 0)
322         {
323           /* This column's datatype is declared as varchar(64). But in current
324              code, there are few process state messages which are greater than
325              64 characters(Eg:stage_slave_has_read_all_relay_log).
326              In those cases, we will end up in 'data truncated'
327              warning/error (depends sql_mode setting) when server is updating
328              this column for those threads. Since 5.6 is GAed, neither the
329              metadata of this column can be changed, nor those state messages.
330              So server will silently truncate the state message to 64 characters
331              if it is longer. In Upper versions(5.7+), these state messages are
332              changed to less than or equal to 64 characters.
333            */
334           set_field_varchar_utf8(f, m_row.m_processlist_state_ptr,
335                                  std::min<uint>(m_row.m_processlist_state_length,
336                                                 f->char_length()));
337         }
338         else
339           f->set_null();
340         break;
341       case 10: /* PROCESSLIST_INFO */
342         if (m_row.m_processlist_info_length > 0)
343           set_field_longtext_utf8(f, m_row.m_processlist_info_ptr,
344                                   m_row.m_processlist_info_length);
345         else
346           f->set_null();
347         break;
348       case 11: /* PARENT_THREAD_ID */
349         if (m_row.m_parent_thread_internal_id != 0)
350           set_field_ulonglong(f, m_row.m_parent_thread_internal_id);
351         else
352           f->set_null();
353         break;
354       case 12: /* ROLE */
355         f->set_null();
356         break;
357       case 13: /* INSTRUMENTED */
358         set_field_enum(f, (m_row.m_enabled_ptr && *m_row.m_enabled_ptr)
359 			? ENUM_YES : ENUM_NO);
360         break;
361       default:
362         DBUG_ASSERT(false);
363       }
364     }
365   }
366   return 0;
367 }
368 
update_row_values(TABLE * table,const unsigned char * old_buf,unsigned char * new_buf,Field ** fields)369 int table_threads::update_row_values(TABLE *table,
370                                      const unsigned char *old_buf,
371                                      unsigned char *new_buf,
372                                      Field **fields)
373 {
374   Field *f;
375   enum_yes_no value;
376 
377   for (; (f= *fields) ; fields++)
378   {
379     if (bitmap_is_set(table->write_set, f->field_index))
380     {
381       switch(f->field_index)
382       {
383       case 0: /* THREAD_ID */
384       case 1: /* NAME */
385       case 2: /* TYPE */
386       case 3: /* PROCESSLIST_ID */
387       case 4: /* PROCESSLIST_USER */
388       case 5: /* PROCESSLIST_HOST */
389       case 6: /* PROCESSLIST_DB */
390       case 7: /* PROCESSLIST_COMMAND */
391       case 8: /* PROCESSLIST_TIME */
392       case 9: /* PROCESSLIST_STATE */
393       case 10: /* PROCESSLIST_INFO */
394       case 11: /* PARENT_THREAD_ID */
395       case 12: /* ROLE */
396         return HA_ERR_WRONG_COMMAND;
397       case 13: /* INSTRUMENTED */
398         if(m_row.m_enabled_ptr == NULL) {
399           return HA_ERR_WRONG_COMMAND;
400         }
401         value= (enum_yes_no) get_field_enum(f);
402         *m_row.m_enabled_ptr= (value == ENUM_YES) ? true : false;
403         break;
404       default:
405         DBUG_ASSERT(false);
406       }
407     }
408   }
409   return 0;
410 }
411 
412