mariadb/client/my_readline.h
Alexey Kopytov 73a7d99331 Fix for bug#41486: extra character appears in BLOB for every
~40Mb after mysqldump/import 
        
When the input string exceeds the maximum allowed size for the 
internal buffer, batch_readline() returns a truncated string. 
Since there was no way for a caller to determine whether the 
string was truncated or not, the command line client assumed 
batch_readline() to always return the whole input string and 
appended a newline character. This resulted in garbled data 
when importing dumps containing strings longer than the 
maximum input buffer size. 
  
Fixed by adding a flag to the batch_readline() interface to 
signal a truncated string to the caller. 
  
Other minor problems fixed during patch implementation: 
 
- The maximum allowed buffer size for batch_readline() was set 
up depending on the client's max_allowed_packet value. It does 
not actully make any sense, as those variables are not 
related. The input buffer size limit is now always set to 1 
MB. 
  
- fill_buffer() did not always set the EOF flag. 
 
- The input buffer could actually grow twice as the specified 
limit due to insufficient checks in intern_read_line(). 

client/my_readline.h:
  Changed the interface of batch_readline().
client/mysql.cc:
  Honor the truncated flag returned by batch_readline() and do  
  not append the newline character if it was set. Since we can't 
  change the interfaces for readline()/fgets() used in the  
  interactive mode, always assume the returned string was not  
  truncated. In addition, always set the batch_readline()  
  internal buffer to 1 MB, independently from the client's  
  max_allowed_packet.
client/readline.cc:
  Added the 'truncated' argument do batch_readline() to signal 
  truncated string to a caller. 
  Fixed fill_buffer() to set the EOF flag correctly. 
  Fixed checks in intern_read_line() to not allow the internal  
  buffer grow past the specified limit.
mysql-test/r/mysql.result:
  Added a test case for bug #41486.
mysql-test/t/mysql.test:
  Added a test case for bug #41486.
2009-03-18 11:18:24 +03:00

33 lines
1.3 KiB
C

/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/* readline for batch mode */
typedef struct st_line_buffer
{
File file;
char *buffer; /* The buffer itself, grown as needed. */
char *end; /* Pointer at buffer end */
char *start_of_line,*end_of_line;
uint bufread; /* Number of bytes to get with each read(). */
uint eof;
ulong max_size;
ulong read_length; /* Length of last read string */
} LINE_BUFFER;
extern LINE_BUFFER *batch_readline_init(ulong max_size,FILE *file);
extern LINE_BUFFER *batch_readline_command(LINE_BUFFER *buffer, my_string str);
extern char *batch_readline(LINE_BUFFER *buffer, bool *truncated);
extern void batch_readline_end(LINE_BUFFER *buffer);