Commit graph

2039 commits

Author SHA1 Message Date
Vladislav Vaintroub
167d250924 MDEV-4742 additions
- return error from natsort_encode_numeric_key, if it would need
to allocate memory. All needed memory was preallocated much earlier.

- Add test for sort order of leading zero vs numeric strings with suffix.
2021-10-14 12:13:04 +02:00
Vladislav Vaintroub
b3cedf63a3 MDEV-4742 - address review comments.
- Remove second optional parameter to natural_sort_key(), and all fraction
handling.

- Rename natsort_num2str() to natsort_encode_length() to show the intention
that it encodes string *lengths*, and not encode whitespaces and what not.

Handles lengths for which log10(len) >= 10,  even if they do not happen for
MariaDB Strings (where length is limited by 32bit, and log10(len) is <= 9)

- Do not let natural sort key grow past max_packet_length.


- Split Item_func_natural_sort_key::val_str() further and add
natsort_encode_numeric_string(), which contains comment on how
whitespaces are handled.

- Simplify, and speedup to_natsort_key() in common case, by removing
handling of weird charsets utf16/32, that encode numbers in several bytes.
In rare cases utf16/32 is used, we'll convert to utf8 prior to
creating keys, and back to original charset afterwards.
2021-10-14 12:13:04 +02:00
Vladislav Vaintroub
5b29d407f6 MDEV-4742 - provide function to sort string in "natural" order
The numbers should be compared as numbers,  while the rest should be compared
as string.

Introduce natural_sort_key() function that transforms original string
so that the lexicographic order of such keys is suitable for
natural sort.
2021-10-14 12:13:04 +02:00
Marko Mäkelä
b4911f5a34 Merge 10.6 into 10.7 2021-10-13 16:37:12 +03:00
Marko Mäkelä
a8379e53e8 Merge 10.5 into 10.6
The changes to galera.galear_var_replicate_myisam_on
in commit d9b933bec6
are omitted due to conflicts
with commit 27d66d644c.
2021-10-13 13:28:12 +03:00
Marko Mäkelä
99bb3fb656 Merge 10.4 into 10.5 2021-10-13 12:33:56 +03:00
Marko Mäkelä
a736a3174a Merge 10.3 into 10.4 2021-10-13 12:03:32 +03:00
Marko Mäkelä
4a7dfda373 Merge 10.2 into 10.3 2021-10-13 11:38:21 +03:00
Sergei Golubchik
57bf8c1f35 MDEV-26646 SFORMAT Does not allow @variable use
If charset aggregation decides to convert arguments to some specific
charset and some arguments are numbers, they'll be wrapped into a
Item_func_conv_charset(), that changes result_type() to STRING_RESULT.

Fix: don't convert numbers, sformat needs their numerical value only.
2021-10-12 13:28:10 +02:00
Sergei Golubchik
6a7c10de92 MDEV-26691 SFORMAT: Pass down FLOAT as FLOAT, without upcast to DOUBLE 2021-10-12 13:28:10 +02:00
Sergei Golubchik
62d4e7e2df remove auto-switch between char and string based on the string length
1. it is against sql way, auto-detection should use metadata, not data,
consider:

create table t1 (qwe varchar(10)) as values ('qwe'),('qw'),('q'),('werty');
select sformat('{:*>5s}', qwe) from t1;

this will auto-break on the third row.

2. using max_char_length() instead of length() fixes that, but
there's a second big issue, fmt < 8.0 doesn't natively support unicode,
so {:c} would only work for one-byte strings, for 'a', not for 'я'

because of all that let's always format strings as strings.
{:c} will only now work for numbers and still only in the ascii range.
2021-10-12 13:28:10 +02:00
Sergei Golubchik
513c8b4c25 cannot allocate a new String[] in the ::val_str() method
String inherits from Sql_alloc, so it's allocated on the thd's memroot,
this cannot be done per row.

Moved String[] allocation into the Item_func_sformat constructor
(not fix_fields(), because we want it on the same memroot where the item
is).
2021-10-12 13:28:10 +02:00
Sergei Golubchik
8150f52e47 support charsets with mbminlen > 1 2021-10-12 13:28:10 +02:00
Sergei Golubchik
6777c67a39 support {:L} with a ',' thousand separator 2021-10-12 13:28:10 +02:00
Sergei Golubchik
519bb2e41c disallow {:p}
by printing a String as an std::string_view, not as a char*
2021-10-12 13:28:10 +02:00
Sergei Golubchik
a363ccd681 misc cleanups
* comment - use the standard style
* no need to reimplement for with while
* TODO comments for not implemented types
* rename the error not to refer to the underlying library, it's
  the implementation detail
* use res->length(0) to set length to 0, but preserve the already
  allocated buffer
* rename main.sformat -> main.func_sformat
* removed a duplicated part of the test
2021-10-12 13:28:10 +02:00
Alan Cueva
e214e60201 MDEV-25015 Custom formatting of strings in MariaDB queries
SFORMAT() SQL function that uses fmtlib (https://fmt.dev/)
for python-like (also Rust, C++20, etc) string formatting

Only fmtlib 7.0.0+ is supported, older fmtlib
produces different results in the test.

No native support for temporal and decimal values,
* TIME_RESULT is handled as STRING_RESULT
* DECIMAL_RESULT as REAL_RESULT
2021-10-12 13:27:36 +02:00
Alexander Barkov
9300b66577 MDEV-24742 Server crashes in Charset::numchars / String::numchars
The crash happened because Item_aes_crypt::val_str() did not
set the character set of the result.
2021-10-11 17:01:47 +04:00
Oleksandr Byelkin
6efb5e9f5e Merge branch '10.5' into 10.6 2021-08-02 10:11:41 +02:00
Oleksandr Byelkin
ae6bdc6769 Merge branch '10.4' into 10.5 2021-07-31 23:19:51 +02:00
Oleksandr Byelkin
7841a7eb09 Merge branch '10.3' into 10.4 2021-07-31 22:59:58 +02:00
Nikita Malyavin
dba7cd25e1 MDEV-25560 Creating table with certain generated column crashes server
Fix RPAD() handling without 3rd argument of padding, in which case default
padding is used.
2021-07-22 22:35:23 +03:00
Marko Mäkelä
b50ea90063 Merge 10.2 into 10.3 2021-07-22 18:57:54 +03:00
Hollow Man
bd711d4f3d Typo fixes in item_strfunc.cc 2021-07-21 10:31:15 +03:00
Sergei Golubchik
c3b5003851 fixes for win32
in win32 stat_info.st_size is __int64, not size_t
2021-05-19 22:58:34 +02:00
Monty
cc125bebfe Fix all warnings given by UBSAN
The 'special' cases where we disable, suppress or circumvent UBSAN are:
- ref10 source (as here we intentionally do some shifts that UBSAN
  complains about.
- x86 version of optimized int#korr() methods. UBSAN do not like unaligned
  memory access of integers.  Fixed by using byte_order_generic.h when
  compiling with UBSAN
- We use smaller thread stack with ASAN and UBSAN, which forced me to
  disable a few tests that prints the thread stack size.
- Verifying class types does not work for shared libraries. I added
  suppression in mysql-test-run.pl for this case.
- Added '#ifdef WITH_UBSAN' when using integer arithmetic where it is
  safe to have overflows (two cases, in item_func.cc).

Things fixed:
- Don't left shift signed values
  (byte_order_generic.h, mysqltest.c, item_sum.cc and many more)
- Don't assign not non existing values to enum variables.
- Ensure that bool and enum values are properly initialized in
  constructors.  This was needed as UBSAN checks that these types has
  correct values when one copies an object.
  (gcalc_tools.h, ha_partition.cc, item_sum.cc, partition_element.h ...)
- Ensure we do not called handler functions on unallocated objects or
  deleted objects.
  (events.cc, sql_acl.cc).
- Fixed bugs in Item_sp::Item_sp() where we did not call constructor
  on Query_arena object.
- Fixed several cast of objects to an incompatible class!
  (Item.cc, Item_buff.cc, item_timefunc.cc, opt_subselect.cc, sql_acl.cc,
   sql_select.cc ...)
- Ensure we do not do integer arithmetic that causes over or underflows.
  This includes also ++ and -- of integers.
  (Item_func.cc, Item_strfunc.cc, item_timefunc.cc, sql_base.cc ...)
- Added JSON_VALUE_UNITIALIZED to json_value_types and ensure that
  value_type is initialized to this instead of to -1, which is not a valid
  enum value for json_value_types.
- Ensure we do not call memcpy() when second argument could be null.

Other things:

- Changed struct st_position to an OBJECT and added an initialization
  function to it to ensure that we do not copy or use uninitialized
  members. The change to a class was also motived that we used "struct
  st_position" and POSITION randomly trough the code which was
  confusing.
- Notably big rewrite in sql_acl.cc to avoid using deleted objects.
- Changed in sql_partition to use '^' instead of '-'. This is safe as
  the operator is either 0 or 0x8000000000000000ULL.
- Added check for select_nr < INT_MAX in JOIN::build_explain() to
  avoid bug when get_select() could return NULL.
- Reordered elements in POSITION for better alignment.
- Changed sql_test.cc::print_plan() to use pointers instead of objects.
- Fixed bug in find_set() where could could execute '1 << -1'.
- Added variable have_sanitizer, used by mtr.  (This variable was before
  only in 10.5 and up).  It can now have one of two values:
  ASAN or UBSAN.
- Moved ~Archive_share() from ha_archive.cc to ha_archive.h and marked
  it virtual. This was an effort to get UBSAN to work with loaded storage
  engines. I kept the change as the new place is better.
- Added in CONNECT engine COLBLK::SetName(), to get around a wrong cast
  in tabutil.cpp.

Changes that should not be needed but had to be done to suppress warnings
from UBSAN:

- Added static_cast<<uint16_t>> around shift to get rid of a LOT of
  compiler warnings when using UBSAN.
- Had to change some '/' of 2 base integers to shift to get rid of
  some compile time warnings.

Fixes:

MDEV-25505 Assertion `old_flags == ((my_flags & 0x10000U) ? 1 : 0)
fixed (was caused by an old version if this commit).

Reviewed by:
- Json changes: Alexey Botchkov
- Charset changes in ctype-uca.c: Alexander Barkov
- InnoDB changes: Marko Mäkelä
- sql_acl.cc changes: Vicențiu Ciorbaru
- build_explain() changes: Sergey Petrunia
Temporary commit to log changes for UBSAN
2021-05-19 22:54:14 +02:00
Monty
b8c3159594 MDEV-24285 support oracle build-in function: sys_guid
SYS_GUID() returns same as UUID(), but without any '-'

author: woqutech
2021-05-19 22:54:11 +02:00
Monty
949d10bea2 Don't reset StringBuffers in loops when not needed
- Moved out creating StringBuffers in loops and instead create them
  outside and just reset the buffer if it was not allocated (to avoid
  a possible malloc/free for every entry)

Other things related to set_buffer_if_not_allocated()
- Changed Valuebuffer to not call set_buffer_if_not_allocated() when
  it is created.
- Fixed geometry functions to reset string length before calling
  String::reserve().  This is because one should not access length()
  of an undefined.
- Added Item_func_conv_charset::save_in_field() as the item is using
  str_value to store cached values, which conflicts with
  Item::save_str_in_field().
- Changed Item_proc_string to not store the string value in sql_string
  as this clashes with Item::save_str_in_field().
- Locally store value of full_name_cstring() in analyse::end_of_records()
  as Item::save_str_in_field() may overwrite it.
- Marked some strings as set_thread_specific()
- Added String::free_buffer() to be used internally in String functions
  to just free the buffer but not reset other String values.
- Fixed uses_buffer_owned_by() to check for allocated length instead of
  strlength, which could be marked MEM_UNDEFINED().
2021-05-19 22:54:11 +02:00
Monty
a206658b98 Change CHARSET_INFO character set and collaction names to LEX_CSTRING
This change removed 68 explict strlen() calls from the code.

The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name

Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible

Other things:
- There where compiler issues with ensuring that all character set names
  points to the same string: gcc doesn't allow one to use integer constants
  when defining global structures (constant char * pointers works fine).
  To get around this, I declared defines for each character set name
  length.
2021-05-19 22:54:07 +02:00
Sergei Golubchik
6de84e6f4e cleanup: Item::can_eval_in_optimize()
a helper method to check whether an item can be evaluated
in the query optimization phase (in and below JOIN::optimize()).
2021-05-19 22:27:53 +02:00
Monty
b6ff139aa3 Reduce usage of strlen()
Changes:
- To detect automatic strlen() I removed the methods in String that
  uses 'const char *' without a length:
  - String::append(const char*)
  - Binary_string(const char *str)
  - String(const char *str, CHARSET_INFO *cs)
  - append_for_single_quote(const char *)
  All usage of append(const char*) is changed to either use
  String::append(char), String::append(const char*, size_t length) or
  String::append(LEX_CSTRING)
- Added STRING_WITH_LEN() around constant string arguments to
  String::append()
- Added overflow argument to escape_string_for_mysql() and
  escape_quotes_for_mysql() instead of returning (size_t) -1 on overflow.
  This was needed as most usage of the above functions never tested the
  result for -1 and would have given wrong results or crashes in case
  of overflows.
- Added Item_func_or_sum::func_name_cstring(), which returns LEX_CSTRING.
  Changed all Item_func::func_name()'s to func_name_cstring()'s.
  The old Item_func_or_sum::func_name() is now an inline function that
  returns func_name_cstring().str.
- Changed Item::mode_name() and Item::func_name_ext() to return
  LEX_CSTRING.
- Changed for some functions the name argument from const char * to
  to const LEX_CSTRING &:
  - Item::Item_func_fix_attributes()
  - Item::check_type_...()
  - Type_std_attributes::agg_item_collations()
  - Type_std_attributes::agg_item_set_converter()
  - Type_std_attributes::agg_arg_charsets...()
  - Type_handler_hybrid_field_type::aggregate_for_result()
  - Type_handler_geometry::check_type_geom_or_binary()
  - Type_handler::Item_func_or_sum_illegal_param()
  - Predicant_to_list_comparator::add_value_skip_null()
  - Predicant_to_list_comparator::add_value()
  - cmp_item_row::prepare_comparators()
  - cmp_item_row::aggregate_row_elements_for_comparison()
  - Cursor_ref::print_func()
- Removes String_space() as it was only used in one cases and that
  could be simplified to not use String_space(), thanks to the fixed
  my_vsnprintf().
- Added some const LEX_CSTRING's for common strings:
  - NULL_clex_str, DATA_clex_str, INDEX_clex_str.
- Changed primary_key_name to a LEX_CSTRING
- Renamed String::set_quick() to String::set_buffer_if_not_allocated() to
  clarify what the function really does.
- Rename of protocol function:
  bool store(const char *from, CHARSET_INFO *cs) to
  bool store_string_or_null(const char *from, CHARSET_INFO *cs).
  This was done to both clarify the difference between this 'store' function
  and also to make it easier to find unoptimal usage of store() calls.
- Added Protocol::store(const LEX_CSTRING*, CHARSET_INFO*)
- Changed some 'const char*' arrays to instead be of type LEX_CSTRING.
- class Item_func_units now used LEX_CSTRING for name.

Other things:
- Fixed a bug in mysql.cc:construct_prompt() where a wrong escape character
  in the prompt would cause some part of the prompt to be duplicated.
- Fixed a lot of instances where the length of the argument to
  append is known or easily obtain but was not used.
- Removed some not needed 'virtual' definition for functions that was
  inherited from the parent. I added override to these.
- Fixed Ordered_key::print() to preallocate needed buffer. Old code could
  case memory overruns.
- Simplified some loops when adding char * to a String with delimiters.
2021-05-19 22:27:48 +02:00
Monty
6079b46d8d Split item->flags into base_flags and with_flags
This was done to simplify copying of with_* flags

Other things:
- Changed Flags to C++ enums, which enables gdb to print
  out bit values for the flags. This also enables compiler
  errors if one tries to manipulate a non existing bit in
  a variable.
- Added set_maybe_null() as a shortcut as setting the
  MAYBE_NULL flags was used in a LOT of places.
- Renamed PARAM flag to SP_VAR to ensure it's not confused with persistent
  statement parameters.
2021-05-19 22:27:28 +02:00
Michael Widenius
3105c9e7a5 Change bitfields in Item to an uint16
The reason for the change is that neither clang or gcc can do efficient
code when several bit fields are change at the same time or when copying
one or more bits between identical bit fields.
Updated bits explicitely with & and | is MUCH more efficient than what
current compilers can do.
2021-05-19 22:27:28 +02:00
Michael Widenius
451c4ae548 Renamed 'flags' variables in Item_class
This is a preparation for adding a flags variable to Item class
2021-05-19 22:27:28 +02:00
Monty
c76eabfb5e Improved storage size for Item, Field and some other classes
- Changed order of class fields to remove dead alignment space.
- Changed bool fields in Item to bit fields.
- Used packed enum's for some fields in common classes
- Removed not used Item::rsize.
- Changed some class variables from uint/int to smaller type int's.
- Ensured that field_index is uint16 in all classes and functions. Fixed
  also that we proparly compare with NO_CACHED_FIELD_INDEX when checking
  if variable is not set.
- Removed checking of highest bit of unireg_check (has not been used in
  a long time)
- Fixed wrong arguments to make_cond_for_table() for join_tab_idx_arg
  from false to 0.

One of the result was reducing the size if class Item with ~24 bytes
2021-05-19 22:27:27 +02:00
Marko Mäkelä
4930f9c94b Merge 10.5 into 10.6 2021-04-21 11:45:00 +03:00
Marko Mäkelä
80ed136e6d Merge 10.4 into 10.5 2021-04-21 09:01:01 +03:00
Oleksandr Byelkin
a3099a3b4a MDEV-24312 master_host has 60 character limit, increase to 255 bytes
Also increase user name up to 128.

The work was started by Rucha Deodhar <rucha.deodhar@mariadb.com>,
contains audit plugin fixes by Alexey Botchkov <holyfoot@askmonty.org>.
2021-04-20 16:36:56 +02:00
Monty
031f11717d Fix all warnings given by UBSAN
The easiest way to compile and test the server with UBSAN is to run:
./BUILD/compile-pentium64-ubsan
and then run mysql-test-run.
After this commit, one should be able to run this without any UBSAN
warnings. There is still a few compiler warnings that should be fixed
at some point, but these do not expose any real bugs.

The 'special' cases where we disable, suppress or circumvent UBSAN are:
- ref10 source (as here we intentionally do some shifts that UBSAN
  complains about.
- x86 version of optimized int#korr() methods. UBSAN do not like unaligned
  memory access of integers.  Fixed by using byte_order_generic.h when
  compiling with UBSAN
- We use smaller thread stack with ASAN and UBSAN, which forced me to
  disable a few tests that prints the thread stack size.
- Verifying class types does not work for shared libraries. I added
  suppression in mysql-test-run.pl for this case.
- Added '#ifdef WITH_UBSAN' when using integer arithmetic where it is
  safe to have overflows (two cases, in item_func.cc).

Things fixed:
- Don't left shift signed values
  (byte_order_generic.h, mysqltest.c, item_sum.cc and many more)
- Don't assign not non existing values to enum variables.
- Ensure that bool and enum values are properly initialized in
  constructors.  This was needed as UBSAN checks that these types has
  correct values when one copies an object.
  (gcalc_tools.h, ha_partition.cc, item_sum.cc, partition_element.h ...)
- Ensure we do not called handler functions on unallocated objects or
  deleted objects.
  (events.cc, sql_acl.cc).
- Fixed bugs in Item_sp::Item_sp() where we did not call constructor
  on Query_arena object.
- Fixed several cast of objects to an incompatible class!
  (Item.cc, Item_buff.cc, item_timefunc.cc, opt_subselect.cc, sql_acl.cc,
   sql_select.cc ...)
- Ensure we do not do integer arithmetic that causes over or underflows.
  This includes also ++ and -- of integers.
  (Item_func.cc, Item_strfunc.cc, item_timefunc.cc, sql_base.cc ...)
- Added JSON_VALUE_UNITIALIZED to json_value_types and ensure that
  value_type is initialized to this instead of to -1, which is not a valid
  enum value for json_value_types.
- Ensure we do not call memcpy() when second argument could be null.
- Fixed that Item_func_str::make_empty_result() creates an empty string
  instead of a null string (safer as it ensures we do not do arithmetic
  on null strings).

Other things:

- Changed struct st_position to an OBJECT and added an initialization
  function to it to ensure that we do not copy or use uninitialized
  members. The change to a class was also motived that we used "struct
  st_position" and POSITION randomly trough the code which was
  confusing.
- Notably big rewrite in sql_acl.cc to avoid using deleted objects.
- Changed in sql_partition to use '^' instead of '-'. This is safe as
  the operator is either 0 or 0x8000000000000000ULL.
- Added check for select_nr < INT_MAX in JOIN::build_explain() to
  avoid bug when get_select() could return NULL.
- Reordered elements in POSITION for better alignment.
- Changed sql_test.cc::print_plan() to use pointers instead of objects.
- Fixed bug in find_set() where could could execute '1 << -1'.
- Added variable have_sanitizer, used by mtr.  (This variable was before
  only in 10.5 and up).  It can now have one of two values:
  ASAN or UBSAN.
- Moved ~Archive_share() from ha_archive.cc to ha_archive.h and marked
  it virtual. This was an effort to get UBSAN to work with loaded storage
  engines. I kept the change as the new place is better.
- Added in CONNECT engine COLBLK::SetName(), to get around a wrong cast
  in tabutil.cpp.
- Added HAVE_REPLICATION around usage of rgi_slave, to get embedded
  server to compile with UBSAN. (Patch from Marko).
- Added #ifdef for powerpc64 to avoid a bug in old gcc versions related
  to integer arithmetic.

Changes that should not be needed but had to be done to suppress warnings
from UBSAN:

- Added static_cast<<uint16_t>> around shift to get rid of a LOT of
  compiler warnings when using UBSAN.
- Had to change some '/' of 2 base integers to shift to get rid of
  some compile time warnings.

Reviewed by:
- Json changes: Alexey Botchkov
- Charset changes in ctype-uca.c: Alexander Barkov
- InnoDB changes & Embedded server: Marko Mäkelä
- sql_acl.cc changes: Vicențiu Ciorbaru
- build_explain() changes: Sergey Petrunia
2021-04-20 12:30:09 +03:00
Monty
55b2788800 Fixed length estimate for REPLACE() 2020-11-26 19:13:37 +02:00
Daniele Sciascia
f8bf5b0f84 MDEV-23466 SIGABRT on SELECT WSREP_LAST_SEEN_GTID
SELECT WSREP_LAST_SEEN_GTID aborts the server if no provider is
loaded.
2020-08-19 13:12:00 +03:00
Marko Mäkelä
cf87f3e08c Merge 10.4 into 10.5 2020-08-14 11:33:35 +03:00
Marko Mäkelä
2f7b37b021 Merge 10.3 into 10.4, except MDEV-22543
Also, fix GCC -Og -Wmaybe-uninitialized in run_backup_stage()
2020-08-13 18:48:41 +03:00
Marko Mäkelä
b811c6ecc7 Fix GCC 10.2.0 -Og -Wmaybe-uninitialized
Fix some more cases after merging
commit 31aef3ae99.
Some warnings look possibly genuine, others are clearly bogus.
2020-08-13 18:21:30 +03:00
Marko Mäkelä
1c58748196 Merge 10.4 into 10.5 2020-08-10 21:38:55 +03:00
Marko Mäkelä
101ddc5e27 Merge mariadb-10.4.14 2020-08-10 20:37:52 +03:00
Alexander Barkov
fe555b9c5f MDEV-23415 Server crash or Assertion `dec_length <= str_length' failed in Item_func_format::val_str_ascii
Problem:

The crash happened in FORMAT(double, dec>=31, 'de_DE').

The patch for MDEV-23118 (commit 0041dacc1b)
did not take into account that String::set_real() has a limit of 31
(FLOATING_POINT_DECIMALS) fractional digits. So for the range of 31..38
digits, set_real() switches to use:
- my_fcvt() - decimal point notation, e.g. 1.9999999999
- my_gcvt() - scientific notation,    e.g. 1e22

my_gcvt() returned a shorter string than Item_func_format::val_str_ascii()
expected to get after the my_fcvt() call, so it crashed on assert.

Solution:

We cannot extend set_real() to use the my_fcvt() mode for the range of
31..38 fractional digits, because set_real() is used in a lot of places
and such a change will break everything.

Introducing String::set_fcvt() which always prints using my_fcvt()
for the whole range of decimals 0..38, supported by the FORMAT() function.
2020-08-08 09:44:31 +04:00
Alexander Barkov
0041dacc1b MDEV-23118 FORMAT(d1,dec) where dec=0/38 and d1 is DECIMAL(38,38) gives incorrect results
FORMAT() can print more integer digits (than the argument has)
if rounding happens:

  FORMAT(9.9,0) -> '10'

The old code did not take this into account.

Fix:

1. One extra digit is needed in case of rounding

- If args[1] is a not-NULL constant, then reserve space for one extra integer
  digit if the requested number of decimals is less than args[0]->decimals.

- Otherwise, reserve space for one extra integer digit if
  args[0]->decimals is not 0, because rounding can potentially happen
  (depending on the exact data in arguments).

2. One extra digit is also needed if the argument has no integer digits,
   e.g. in a data type like DECIMAL(38,38).

The conditions 1 and 2 are ORed.

3. Fixing FORMAT_MAX_DECIMALS from 30 to 38. This was forgotten in 10.2.1
   (when the limit for the number of fractional digits in DECIMAL was extended).
2020-08-05 08:56:12 +04:00
Oleksandr Byelkin
48b5777ebd Merge branch '10.4' into 10.5 2020-08-04 17:24:15 +02:00
Oleksandr Byelkin
57325e4706 Merge branch '10.3' into 10.4 2020-08-03 14:44:06 +02:00