1 /*
2 Copyright (c) 2000, 2010, 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 as published by
6 the Free Software Foundation; version 2 of the License.
7
8 This program is distributed in the hope that it will be useful,
9 but WITHOUT ANY WARRANTY; without even the implied warranty of
10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 GNU General Public License for more details.
12
13 You should have received a copy of the GNU General Public License
14 along with this program; if not, write to the Free Software
15 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
16
17
18 /* Mallocs for used in threads */
19
20 #include "mariadb.h"
21 #include "sql_priv.h"
22 #include "unireg.h"
23 #include "thr_malloc.h"
24 #include "sql_class.h"
25
26 extern "C" {
sql_alloc_error_handler(void)27 void sql_alloc_error_handler(void)
28 {
29 THD *thd= current_thd;
30 if (likely(thd))
31 {
32 if (! thd->is_error())
33 {
34 /*
35 This thread is Out Of Memory.
36 An OOM condition is a fatal error.
37 It should not be caught by error handlers in stored procedures.
38 Also, recording that SQL condition in the condition area could
39 cause more memory allocations, which in turn could raise more
40 OOM conditions, causing recursion in the error handling code itself.
41 As a result, my_error() should not be invoked, and the
42 thread diagnostics area is set to an error status directly.
43 Note that Diagnostics_area::set_error_status() is safe,
44 since it does not call any memory allocation routines.
45 The visible result for a client application will be:
46 - a query fails with an ER_OUT_OF_RESOURCES error,
47 returned in the error packet.
48 - SHOW ERROR/SHOW WARNINGS may be empty.
49 */
50 thd->get_stmt_da()->set_error_status(ER_OUT_OF_RESOURCES);
51 }
52 }
53
54 /* Skip writing to the error log to avoid mtr complaints */
55 DBUG_EXECUTE_IF("simulate_out_of_memory", return;);
56
57 sql_print_error("%s", ER_THD_OR_DEFAULT(thd, ER_OUT_OF_RESOURCES));
58 }
59 }
60
init_sql_alloc(MEM_ROOT * mem_root,const char * area_name,uint block_size,uint pre_alloc,myf my_flags)61 void init_sql_alloc(MEM_ROOT *mem_root,
62 const char *area_name __attribute__((unused)),
63 uint block_size, uint pre_alloc, myf my_flags)
64 {
65 init_alloc_root(mem_root, area_name, block_size, pre_alloc, my_flags);
66 mem_root->error_handler=sql_alloc_error_handler;
67 }
68
69
sql_strmake_with_convert(THD * thd,const char * str,size_t arg_length,CHARSET_INFO * from_cs,size_t max_res_length,CHARSET_INFO * to_cs,size_t * result_length)70 char *sql_strmake_with_convert(THD *thd, const char *str, size_t arg_length,
71 CHARSET_INFO *from_cs,
72 size_t max_res_length,
73 CHARSET_INFO *to_cs, size_t *result_length)
74 {
75 char *pos;
76 size_t new_length= to_cs->mbmaxlen*arg_length;
77 max_res_length--; // Reserve place for end null
78
79 set_if_smaller(new_length, max_res_length);
80 if (!(pos= (char*) thd->alloc(new_length + 1)))
81 return pos; // Error
82
83 if ((from_cs == &my_charset_bin) || (to_cs == &my_charset_bin))
84 {
85 // Safety if to_cs->mbmaxlen > 0
86 new_length= MY_MIN(arg_length, max_res_length);
87 memcpy(pos, str, new_length);
88 }
89 else
90 {
91 uint dummy_errors;
92 new_length= copy_and_convert((char*) pos, new_length, to_cs, str,
93 arg_length, from_cs, &dummy_errors);
94 }
95 pos[new_length]= 0;
96 *result_length= new_length;
97 return pos;
98 }
99
100