diff --git a/sql/protocol.cc b/sql/protocol.cc index 6a17ae2f95b6868112b1e1f9afbb4c9d3248e306..a2287740f1eeb3bd769b751e7ad5a598afd17333 100644 --- a/sql/protocol.cc +++ b/sql/protocol.cc @@ -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); diff --git a/tests/mysql_client_test.c b/tests/mysql_client_test.c index 797a0b1b8d7bb20440c9f99c7843ce7a3cbd24d4..91c2ab9205d93d0f033f9e06351417195cad87b4 100644 --- a/tests/mysql_client_test.c +++ b/tests/mysql_client_test.c @@ -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 } };