Fix for Bug#56934 (mysql_stmt_fetch() incorrectly fills MYSQL_TIME

structure buffer).

This is a follow-up for WL#4435. The bug actually existed not only
MYSQL_TYPE_DATETIME type. The problem was that Item_param::set_value()
was written in an assumption that it's working with expressions, i.e.
with basic data types.

There are two different quick fixes here:
  a) Change Item_param::make_field() -- remove setting of
     Send_field::length, Send_field::charsetnr, Send_field::flags and
     Send_field::type.

     That would lead to marshalling all data using basic types to the client
     (MYSQL_TYPE_LONGLONG, MYSQL_TYPE_DOUBLE, MYSQL_TYPE_STRING and
     MYSQL_TYPE_NEWDECIMAL). In particular, that means, DATETIME would be
     sent as MYSQL_TYPE_STRING, TINYINT -- as MYSQL_TYPE_LONGLONG, etc.

     That could be Ok for the client, because the client library does
     reverse conversion automatically (the client program would see DATETIME
     as MYSQL_TIME object). However, there is a problem with metadata --
     the metadata would be wrong (misleading): it would say that DATETIME is
     marshaled as MYSQL_TYPE_DATETIME, not as MYSQL_TYPE_STRING.

  b) Set Item_param::param_type properly to actual underlying field type.
     That would lead to double conversion inside the server: for example,
     MYSQL_TIME-object would be converted into STRING-object
     (in Item_param::set_value()), and then converted back to MYSQL_TIME-object
     (in Item_param::send()).

     The data however would be marshalled more properly, and also metadata would
     be correct.

This patch implements b).

There is also a possibility to avoid double conversion either by clonning
the data field, or by storing a reference to it and using it on Item::send()
time. That requires more work and might be done later.

mysql-test/t/ps.test

@@ -3296,6 +3296,12 @@ SELECT @a;
 DROP PROCEDURE p1;
 DROP PROCEDURE p2;
 
+###########################################################################
+
+--source t/wl4435_generated.inc
+
+###########################################################################
+
 --echo
 --echo # End of WL#4435.
 

sql/item.cc

@@ -226,8 +226,6 @@ bool Item::val_bool()
 */
 String *Item::val_str_ascii(String *str)
 {
-  DBUG_ASSERT(fixed == 1);
-
   if (!(collation.collation->state & MY_CS_NONASCII))
     return val_str(str);
   
@@ -3459,19 +3457,16 @@ Item_param::set_value(THD *thd, sp_rcontext *ctx, Item **it)
                       str_value.charset());
     collation.set(str_value.charset(), DERIVATION_COERCIBLE);
     decimals= 0;
-    param_type= MYSQL_TYPE_STRING;
 
     break;
   }
 
   case REAL_RESULT:
     set_double(arg->val_real());
-      param_type= MYSQL_TYPE_DOUBLE;
     break;
 
   case INT_RESULT:
     set_int(arg->val_int(), arg->max_length);
-    param_type= MYSQL_TYPE_LONG;
     break;
 
   case DECIMAL_RESULT:
@@ -3483,8 +3478,6 @@ Item_param::set_value(THD *thd, sp_rcontext *ctx, Item **it)
       return TRUE;
 
     set_decimal(dv);
-    param_type= MYSQL_TYPE_NEWDECIMAL;
-
     break;
   }
 
@@ -3516,6 +3509,7 @@ void
 Item_param::set_out_param_info(Send_field *info)
 {
   m_out_param_info= info;
+  param_type= m_out_param_info->type;
 }
 
 
@@ -3561,6 +3555,7 @@ void Item_param::make_field(Send_field *field)
   field->org_table_name= m_out_param_info->org_table_name;
   field->col_name= m_out_param_info->col_name;
   field->org_col_name= m_out_param_info->org_col_name;
+
   field->length= m_out_param_info->length;
   field->charsetnr= m_out_param_info->charsetnr;
   field->flags= m_out_param_info->flags;

sql/sp_rcontext.h

@@ -220,6 +220,7 @@ class sp_rcontext : public Sql_alloc
     during execution.
   */
   bool m_return_value_set;
+
   /**
     TRUE if the context is created for a sub-statement.
   */

sql/sql_prepare.cc

@@ -1185,7 +1185,7 @@ static bool insert_params_from_vars_with_log(Prepared_statement *stmt,
   uint32 length= 0;
   THD *thd= stmt->thd;
 
-  DBUG_ENTER("insert_params_from_vars");
+  DBUG_ENTER("insert_params_from_vars_with_log");
 
   if (query->copy(stmt->query(), stmt->query_length(), default_charset_info))
     DBUG_RETURN(1);

tests/mysql_client_test.c

@@ -2103,6 +2103,255 @@ static void test_wl4435_2()
 }
 
 
+#define WL4435_TEST(sql_type, sql_value, \
+                    c_api_in_type, c_api_out_type, \
+                    c_type, c_type_ext, \
+                    printf_args, assert_condition) \
+\
+  do { \
+  int rc; \
+  MYSQL_STMT *ps; \
+  MYSQL_BIND psp; \
+  MYSQL_RES *rs_metadata; \
+  MYSQL_FIELD *fields; \
+  c_type pspv c_type_ext; \
+  my_bool psp_null; \
+  \
+  bzero(&pspv, sizeof (pspv)); \
+  \
+  rc= mysql_query(mysql, "DROP PROCEDURE IF EXISTS p1"); \
+  myquery(rc); \
+  \
+  rc= mysql_query(mysql, \
+    "CREATE PROCEDURE p1(OUT v " sql_type ") SET v = " sql_value ";"); \
+  myquery(rc); \
+  \
+  ps = mysql_simple_prepare(mysql, "CALL p1(?)"); \
+  check_stmt(ps); \
+  \
+  bzero(&psp, sizeof (psp)); \
+  psp.buffer_type= c_api_in_type; \
+  psp.is_null= &psp_null; \
+  psp.buffer= (char *) &pspv; \
+  psp.buffer_length= sizeof (psp); \
+  \
+  rc= mysql_stmt_bind_param(ps, &psp); \
+  check_execute(ps, rc); \
+  \
+  rc= mysql_stmt_execute(ps); \
+  check_execute(ps, rc); \
+  \
+  DIE_UNLESS(mysql->server_status & SERVER_PS_OUT_PARAMS); \
+  DIE_UNLESS(mysql_stmt_field_count(ps) == 1); \
+  \
+  rs_metadata= mysql_stmt_result_metadata(ps); \
+  fields= mysql_fetch_fields(rs_metadata); \
+  \
+  rc= mysql_stmt_bind_result(ps, &psp); \
+  check_execute(ps, rc); \
+  \
+  rc= mysql_stmt_fetch(ps); \
+  DIE_UNLESS(rc == 0); \
+  \
+  DIE_UNLESS(fields[0].type == c_api_out_type); \
+  printf printf_args; \
+  printf("; in type: %d; out type: %d\n", \
+         (int) c_api_in_type, (int) c_api_out_type); \
+  \
+  rc= mysql_stmt_fetch(ps); \
+  DIE_UNLESS(rc == MYSQL_NO_DATA); \
+  \
+  rc= mysql_stmt_next_result(ps); \
+  DIE_UNLESS(rc == 0); \
+  \
+  mysql_stmt_free_result(ps); \
+  mysql_stmt_close(ps); \
+  \
+  DIE_UNLESS(assert_condition); \
+  \
+  } while (0)
+
+static void test_wl4435_3()
+{
+  char tmp[255];
+
+  puts("");
+
+  // The following types are not supported:
+  //   - ENUM
+  //   - SET
+  //
+  // The following types are supported but can not be used for
+  // OUT-parameters:
+  //   - MEDIUMINT;
+  //   - BIT(..);
+  //
+  // The problem is that those types are not supported for IN-parameters,
+  // and OUT-parameters should be bound as IN-parameters before execution.
+  //
+  // The following types should not be used:
+  //   - MYSQL_TYPE_YEAR (use MYSQL_TYPE_SHORT instead);
+  //   - MYSQL_TYPE_TINY_BLOB, MYSQL_TYPE_MEDIUM_BLOB, MYSQL_TYPE_LONG_BLOB
+  //     (use MYSQL_TYPE_BLOB instead);
+
+  WL4435_TEST("TINYINT", "127",
+              MYSQL_TYPE_TINY, MYSQL_TYPE_TINY,
+              char, ,
+              ("  - TINYINT / char / MYSQL_TYPE_TINY:\t\t\t %d", (int) pspv),
+              pspv == 127);
+
+  WL4435_TEST("SMALLINT", "32767",
+              MYSQL_TYPE_SHORT, MYSQL_TYPE_SHORT,
+              short, ,
+              ("  - SMALLINT / short / MYSQL_TYPE_SHORT:\t\t %d", (int) pspv),
+              pspv == 32767);
+
+  WL4435_TEST("INT", "2147483647",
+              MYSQL_TYPE_LONG, MYSQL_TYPE_LONG,
+              int, ,
+              ("  - INT / int / MYSQL_TYPE_LONG:\t\t\t %d", pspv),
+              pspv == 2147483647l);
+
+  WL4435_TEST("BIGINT", "9223372036854775807",
+              MYSQL_TYPE_LONGLONG, MYSQL_TYPE_LONGLONG,
+              long long, ,
+              ("  - BIGINT / long long / MYSQL_TYPE_LONGLONG:\t\t %lld", pspv),
+              pspv == 9223372036854775807ll);
+
+  WL4435_TEST("TIMESTAMP", "'2007-11-18 15:01:02'",
+              MYSQL_TYPE_TIMESTAMP, MYSQL_TYPE_TIMESTAMP,
+              MYSQL_TIME, ,
+              ("  - TIMESTAMP / MYSQL_TIME / MYSQL_TYPE_TIMESTAMP:\t "
+               "%.4d-%.2d-%.2d %.2d:%.2d:%.2d",
+               (int) pspv.year, (int) pspv.month, (int) pspv.day,
+               (int) pspv.hour, (int) pspv.minute, (int) pspv.second),
+              pspv.year == 2007 && pspv.month == 11 && pspv.day == 18 &&
+              pspv.hour == 15 && pspv.minute == 1 && pspv.second == 2);
+
+  WL4435_TEST("DATETIME", "'1234-11-12 12:34:59'",
+              MYSQL_TYPE_DATETIME, MYSQL_TYPE_DATETIME,
+              MYSQL_TIME, ,
+              ("  - DATETIME / MYSQL_TIME / MYSQL_TYPE_DATETIME:\t "
+               "%.4d-%.2d-%.2d %.2d:%.2d:%.2d",
+               (int) pspv.year, (int) pspv.month, (int) pspv.day,
+               (int) pspv.hour, (int) pspv.minute, (int) pspv.second),
+              pspv.year == 1234 && pspv.month == 11 && pspv.day == 12 &&
+              pspv.hour == 12 && pspv.minute == 34 && pspv.second == 59);
+
+  WL4435_TEST("TIME", "'123:45:01'",
+              MYSQL_TYPE_TIME, MYSQL_TYPE_TIME,
+              MYSQL_TIME, ,
+              ("  - TIME / MYSQL_TIME / MYSQL_TYPE_TIME:\t\t "
+               "%.3d:%.2d:%.2d",
+               (int) pspv.hour, (int) pspv.minute, (int) pspv.second),
+              pspv.hour == 123 && pspv.minute == 45 && pspv.second == 1);
+
+  WL4435_TEST("DATE", "'1234-11-12'",
+              MYSQL_TYPE_DATE, MYSQL_TYPE_DATE,
+              MYSQL_TIME, ,
+              ("  - DATE / MYSQL_TIME / MYSQL_TYPE_DATE:\t\t "
+               "%.4d-%.2d-%.2d",
+               (int) pspv.year, (int) pspv.month, (int) pspv.day),
+              pspv.year == 1234 && pspv.month == 11 && pspv.day == 12);
+
+  WL4435_TEST("YEAR", "'2010'",
+              MYSQL_TYPE_SHORT, MYSQL_TYPE_YEAR,
+              short, ,
+              ("  - YEAR / short / MYSQL_TYPE_SHORT:\t\t\t %.4d", (int) pspv),
+              pspv == 2010);
+
+  WL4435_TEST("FLOAT(7, 4)", "123.4567",
+              MYSQL_TYPE_FLOAT, MYSQL_TYPE_FLOAT,
+              float, ,
+              ("  - FLOAT / float / MYSQL_TYPE_FLOAT:\t\t\t %g", (double) pspv),
+              pspv - 123.4567 < 0.0001);
+
+  WL4435_TEST("DOUBLE(8, 5)", "123.45678",
+              MYSQL_TYPE_DOUBLE, MYSQL_TYPE_DOUBLE,
+              double, ,
+              ("  - DOUBLE / double / MYSQL_TYPE_DOUBLE:\t\t %g", (double) pspv),
+              pspv - 123.45678 < 0.00001);
+
+  WL4435_TEST("DECIMAL(9, 6)", "123.456789",
+              MYSQL_TYPE_NEWDECIMAL, MYSQL_TYPE_NEWDECIMAL,
+              char, [255],
+              ("  - DECIMAL / char[] / MYSQL_TYPE_NEWDECIMAL:\t\t '%s'", (char *) pspv),
+              !strcmp(pspv, "123.456789"));
+
+  WL4435_TEST("CHAR(32)", "REPEAT('C', 16)",
+              MYSQL_TYPE_STRING, MYSQL_TYPE_STRING,
+              char, [255],
+              ("  - CHAR(32) / char[] / MYSQL_TYPE_STRING:\t\t '%s'", (char *) pspv),
+              !strcmp(pspv, "CCCCCCCCCCCCCCCC"));
+
+  WL4435_TEST("VARCHAR(32)", "REPEAT('V', 16)",
+              MYSQL_TYPE_VAR_STRING, MYSQL_TYPE_VAR_STRING,
+              char, [255],
+              ("  - VARCHAR(32) / char[] / MYSQL_TYPE_VAR_STRING:\t '%s'", (char *) pspv),
+              !strcmp(pspv, "VVVVVVVVVVVVVVVV"));
+
+  WL4435_TEST("TINYTEXT", "REPEAT('t', 16)",
+              MYSQL_TYPE_TINY_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - TINYTEXT / char[] / MYSQL_TYPE_TINY_BLOB:\t\t '%s'", (char *) pspv),
+              !strcmp(pspv, "tttttttttttttttt"));
+
+  WL4435_TEST("TEXT", "REPEAT('t', 16)",
+              MYSQL_TYPE_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - TEXT / char[] / MYSQL_TYPE_BLOB:\t\t\t '%s'", (char *) pspv),
+              !strcmp(pspv, "tttttttttttttttt"));
+
+  WL4435_TEST("MEDIUMTEXT", "REPEAT('t', 16)",
+              MYSQL_TYPE_MEDIUM_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - MEDIUMTEXT / char[] / MYSQL_TYPE_MEDIUM_BLOB:\t '%s'", (char *) pspv),
+              !strcmp(pspv, "tttttttttttttttt"));
+
+  WL4435_TEST("LONGTEXT", "REPEAT('t', 16)",
+              MYSQL_TYPE_LONG_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - LONGTEXT / char[] / MYSQL_TYPE_LONG_BLOB:\t\t '%s'", (char *) pspv),
+              !strcmp(pspv, "tttttttttttttttt"));
+
+  WL4435_TEST("BINARY(32)", "REPEAT('\1', 16)",
+              MYSQL_TYPE_STRING, MYSQL_TYPE_STRING,
+              char, [255],
+              ("  - BINARY(32) / char[] / MYSQL_TYPE_STRING:\t\t '%s'", (char *) pspv),
+              memset(tmp, 1, 16) && !memcmp(tmp, pspv, 16));
+
+  WL4435_TEST("VARBINARY(32)", "REPEAT('\1', 16)",
+              MYSQL_TYPE_VAR_STRING, MYSQL_TYPE_VAR_STRING,
+              char, [255],
+              ("  - VARBINARY(32) / char[] / MYSQL_TYPE_VAR_STRING:\t '%s'", (char *) pspv),
+              memset(tmp, 1, 16) && !memcmp(tmp, pspv, 16));
+
+  WL4435_TEST("TINYBLOB", "REPEAT('\2', 16)",
+              MYSQL_TYPE_TINY_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - TINYBLOB / char[] / MYSQL_TYPE_TINY_BLOB:\t\t '%s'", (char *) pspv),
+              memset(tmp, 2, 16) && !memcmp(tmp, pspv, 16));
+
+  WL4435_TEST("BLOB", "REPEAT('\2', 16)",
+              MYSQL_TYPE_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - BLOB / char[] / MYSQL_TYPE_BLOB:\t\t\t '%s'", (char *) pspv),
+              memset(tmp, 2, 16) && !memcmp(tmp, pspv, 16));
+
+  WL4435_TEST("MEDIUMBLOB", "REPEAT('\2', 16)",
+              MYSQL_TYPE_MEDIUM_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - MEDIUMBLOB / char[] / MYSQL_TYPE_MEDIUM_BLOB:\t '%s'", (char *) pspv),
+              memset(tmp, 2, 16) && !memcmp(tmp, pspv, 16));
+
+  WL4435_TEST("LONGBLOB", "REPEAT('\2', 16)",
+              MYSQL_TYPE_LONG_BLOB, MYSQL_TYPE_BLOB,
+              char, [255],
+              ("  - LONGBLOB / char[] / MYSQL_TYPE_LONG_BLOB:\t\t '%s'", (char *) pspv),
+              memset(tmp, 2, 16) && !memcmp(tmp, pspv, 16));
+}
+
+
 /* Test simple prepare field results */
 
 static void test_prepare_field_result()
@@ -19468,6 +19717,7 @@ static struct my_tests_st my_tests[]= {
   { "test_wl4284_1", test_wl4284_1 },
   { "test_wl4435",   test_wl4435 },
   { "test_wl4435_2", test_wl4435_2 },
+  { "test_wl4435_3", test_wl4435_3 },
   { "test_bug38486", test_bug38486 },
   { "test_bug33831", test_bug33831 },
   { "test_bug40365", test_bug40365 },