Commit 1e8e302e authored by unknown's avatar unknown
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A fix and a test case for Bug#15613 "libmysqlclient API function 

 mysql_stmt_prepare returns wrong field length"


sql/protocol.cc:
  A fix for Bug#15613: make sure that result set column length
  is evaluated correctly for BLOB/TEXT columns.
tests/mysql_client_test.c:
  A test case for Bug#15613
parent 98448401

sql/protocol.cc

+16 −2
Original line number Diff line number Diff line
@@ -565,9 +565,23 @@ bool Protocol::send_fields(List<Item> *list, uint flag) 
      else

      {

        /* With conversion */

        uint max_char_len;

        int2store(pos, thd_charset->number);

        uint char_len= field.length / item->collation.collation->mbmaxlen;

        int4store(pos+2, char_len * thd_charset->mbmaxlen);

        /*

          For TEXT/BLOB columns, field_length describes the maximum data

          length in bytes. There is no limit to the number of characters

          that a TEXT column can store, as long as the data fits into

          the designated space.

          For the rest of textual columns, field_length is evaluated as

          char_count * mbmaxlen, where character count is taken from the

          definition of the column. In other words, the maximum number

          of characters here is limited by the column definition.

        */

        max_char_len= (field.type >= (int) MYSQL_TYPE_TINY_BLOB &&

                      field.type <= (int) MYSQL_TYPE_BLOB) ?

                      field.length / item->collation.collation->mbminlen :

                      field.length / item->collation.collation->mbmaxlen;

        int4store(pos+2, max_char_len * thd_charset->mbmaxlen);

      }

      pos[6]= field.type;

      int2store(pos+7,field.flags);

tests/mysql_client_test.c

+65 −0
Original line number Diff line number Diff line
@@ -11772,6 +11772,70 @@ static void test_bug16144() 
}





/*

  Bug #15613: "libmysqlclient API function mysql_stmt_prepare returns wrong

  field length"

*/



static void test_bug15613()

{

  MYSQL_STMT *stmt;

  const char *stmt_text;

  MYSQL_RES *metadata;

  MYSQL_FIELD *field;

  int rc;

  myheader("test_bug15613");



  /* I. Prepare the table */

  rc= mysql_query(mysql, "set names latin1");

  myquery(rc);

  mysql_query(mysql, "drop table if exists t1");

  rc= mysql_query(mysql,

                  "create table t1 (t text character set utf8, "

                                   "tt tinytext character set utf8, "

                                   "mt mediumtext character set utf8, "

                                   "lt longtext character set utf8, "

                                   "vl varchar(255) character set latin1,"

                                   "vb varchar(255) character set binary,"

                                   "vu varchar(255) character set utf8)");

  myquery(rc);



  stmt= mysql_stmt_init(mysql);



  /* II. Check SELECT metadata */

  stmt_text= ("select t, tt, mt, lt, vl, vb, vu from t1");

  rc= mysql_stmt_prepare(stmt, stmt_text, strlen(stmt_text));

  metadata= mysql_stmt_result_metadata(stmt);

  field= mysql_fetch_fields(metadata);

  if (!opt_silent)

  {

    printf("Field lengths (client character set is latin1):\n"

           "text character set utf8:\t\t%lu\n"

           "tinytext character set utf8:\t\t%lu\n"

           "mediumtext character set utf8:\t\t%lu\n"

           "longtext character set utf8:\t\t%lu\n"

           "varchar(255) character set latin1:\t%lu\n"

           "varchar(255) character set binary:\t%lu\n"

           "varchar(255) character set utf8:\t%lu\n",

           field[0].length, field[1].length, field[2].length, field[3].length,

           field[4].length, field[5].length, field[6].length);

  }

  DIE_UNLESS(field[0].length == 65535);

  DIE_UNLESS(field[1].length == 255);

  DIE_UNLESS(field[2].length == 16777215);

  DIE_UNLESS(field[3].length == 4294967295UL);

  DIE_UNLESS(field[4].length == 255);

  DIE_UNLESS(field[5].length == 255);

  DIE_UNLESS(field[6].length == 255);



  /* III. Cleanup */

  rc= mysql_query(mysql, "drop table t1");

  myquery(rc);

  rc= mysql_query(mysql, "set names default");

  myquery(rc);

  mysql_stmt_close(stmt);

}



/*

  Read and parse arguments and MySQL options from my.cnf

*/
@@ -11994,6 +12058,7 @@ static struct my_tests_st my_tests[]= { 
  { "test_bug11718", test_bug11718 },

  { "test_bug12925", test_bug12925 },

  { "test_bug16144", test_bug16144 },

  { "test_bug15613", test_bug15613 },

  { 0, 0 }

};