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-rw-r--r--sql/field_conv.cc873
1 files changed, 873 insertions, 0 deletions
diff --git a/sql/field_conv.cc b/sql/field_conv.cc
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--- /dev/null
+++ b/sql/field_conv.cc
@@ -0,0 +1,873 @@
+/* Copyright (c) 2000, 2016, Oracle and/or its affiliates.
+ Copyright (c) 2010, 2020, MariaDB Corporation
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+
+/**
+ @file
+
+ @brief
+ Functions to copy data to or from fields
+
+ This could be done with a single short function but opencoding this
+ gives much more speed.
+*/
+
+#include "mariadb.h"
+#include "sql_priv.h"
+#include "sql_class.h" // THD
+#include <m_ctype.h>
+
+void Field::do_field_eq(Copy_field *copy)
+{
+ memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);
+}
+
+static void do_field_1(Copy_field *copy)
+{
+ copy->to_ptr[0]=copy->from_ptr[0];
+}
+
+static void do_field_2(Copy_field *copy)
+{
+ copy->to_ptr[0]=copy->from_ptr[0];
+ copy->to_ptr[1]=copy->from_ptr[1];
+}
+
+static void do_field_3(Copy_field *copy)
+{
+ copy->to_ptr[0]=copy->from_ptr[0];
+ copy->to_ptr[1]=copy->from_ptr[1];
+ copy->to_ptr[2]=copy->from_ptr[2];
+}
+
+static void do_field_4(Copy_field *copy)
+{
+ copy->to_ptr[0]=copy->from_ptr[0];
+ copy->to_ptr[1]=copy->from_ptr[1];
+ copy->to_ptr[2]=copy->from_ptr[2];
+ copy->to_ptr[3]=copy->from_ptr[3];
+}
+
+static void do_field_6(Copy_field *copy)
+{ // For blob field
+ copy->to_ptr[0]=copy->from_ptr[0];
+ copy->to_ptr[1]=copy->from_ptr[1];
+ copy->to_ptr[2]=copy->from_ptr[2];
+ copy->to_ptr[3]=copy->from_ptr[3];
+ copy->to_ptr[4]=copy->from_ptr[4];
+ copy->to_ptr[5]=copy->from_ptr[5];
+}
+
+static void do_field_8(Copy_field *copy)
+{
+ copy->to_ptr[0]=copy->from_ptr[0];
+ copy->to_ptr[1]=copy->from_ptr[1];
+ copy->to_ptr[2]=copy->from_ptr[2];
+ copy->to_ptr[3]=copy->from_ptr[3];
+ copy->to_ptr[4]=copy->from_ptr[4];
+ copy->to_ptr[5]=copy->from_ptr[5];
+ copy->to_ptr[6]=copy->from_ptr[6];
+ copy->to_ptr[7]=copy->from_ptr[7];
+}
+
+
+static void do_field_to_null_str(Copy_field *copy)
+{
+ if (*copy->from_null_ptr & copy->from_bit)
+ {
+ bzero(copy->to_ptr,copy->from_length);
+ copy->to_null_ptr[0]=1; // Always bit 1
+ }
+ else
+ {
+ copy->to_null_ptr[0]=0;
+ memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);
+ }
+}
+
+
+static void do_outer_field_to_null_str(Copy_field *copy)
+{
+ if (*copy->null_row ||
+ (copy->from_null_ptr && (*copy->from_null_ptr & copy->from_bit)))
+ {
+ bzero(copy->to_ptr,copy->from_length);
+ copy->to_null_ptr[0]=1; // Always bit 1
+ }
+ else
+ {
+ copy->to_null_ptr[0]=0;
+ memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);
+ }
+}
+
+
+static int set_bad_null_error(Field *field, int err)
+{
+ switch (field->table->in_use->count_cuted_fields) {
+ case CHECK_FIELD_WARN:
+ field->set_warning(Sql_condition::WARN_LEVEL_WARN, err, 1);
+ /* fall through */
+ case CHECK_FIELD_IGNORE:
+ case CHECK_FIELD_EXPRESSION:
+ return 0;
+ case CHECK_FIELD_ERROR_FOR_NULL:
+ if (!field->table->in_use->no_errors)
+ my_error(ER_BAD_NULL_ERROR, MYF(0), field->field_name.str);
+ return -1;
+ }
+ DBUG_ASSERT(0); // impossible
+ return -1;
+}
+
+
+int set_field_to_null(Field *field)
+{
+ if (field->table->null_catch_flags & CHECK_ROW_FOR_NULLS_TO_REJECT)
+ {
+ field->table->null_catch_flags|= REJECT_ROW_DUE_TO_NULL_FIELDS;
+ return -1;
+ }
+ if (field->real_maybe_null())
+ {
+ field->set_null();
+ field->reset();
+ return 0;
+ }
+ field->reset();
+ return set_bad_null_error(field, WARN_DATA_TRUNCATED);
+}
+
+
+/**
+ Set TIMESTAMP to NOW(), AUTO_INCREMENT to the next number, or report an error
+
+ @param field Field to update
+
+ @retval
+ 0 Field could take 0 or an automatic conversion was used
+ @retval
+ -1 Field could not take NULL and no conversion was used.
+ If no_conversion was not set, an error message is printed
+*/
+
+int convert_null_to_field_value_or_error(Field *field)
+{
+ if (field->type() == MYSQL_TYPE_TIMESTAMP)
+ {
+ field->set_time();
+ return 0;
+ }
+
+ field->reset(); // Note: we ignore any potential failure of reset() here.
+
+ if (field == field->table->next_number_field)
+ {
+ field->table->auto_increment_field_not_null= FALSE;
+ return 0; // field is set in fill_record()
+ }
+ return set_bad_null_error(field, ER_BAD_NULL_ERROR);
+}
+
+/**
+ Set field to NULL or TIMESTAMP or to next auto_increment number.
+
+ @param field Field to update
+ @param no_conversions Set to 1 if we should return 1 if field can't
+ take null values.
+ If set to 0 we will do store the 'default value'
+ if the field is a special field. If not we will
+ give an error.
+
+ @retval
+ 0 Field could take 0 or an automatic conversion was used
+ @retval
+ -1 Field could not take NULL and no conversion was used.
+ If no_conversion was not set, an error message is printed
+*/
+
+int
+set_field_to_null_with_conversions(Field *field, bool no_conversions)
+{
+ if (field->table->null_catch_flags & CHECK_ROW_FOR_NULLS_TO_REJECT)
+ {
+ field->table->null_catch_flags|= REJECT_ROW_DUE_TO_NULL_FIELDS;
+ return -1;
+ }
+ if (field->real_maybe_null())
+ {
+ field->set_null();
+ field->reset();
+ return 0;
+ }
+ if (no_conversions)
+ return -1;
+
+ return convert_null_to_field_value_or_error(field);
+}
+
+
+static void do_skip(Copy_field *copy __attribute__((unused)))
+{
+}
+
+
+/*
+ Copy: (NULLable field) -> (NULLable field)
+
+ note: if the record we're copying from is NULL-complemetned (i.e.
+ from_field->table->null_row==1), it will also have all NULLable columns to be
+ set to NULLs, so we don't need to check table->null_row here.
+*/
+
+static void do_copy_null(Copy_field *copy)
+{
+ if (*copy->from_null_ptr & copy->from_bit)
+ {
+ *copy->to_null_ptr|=copy->to_bit;
+ copy->to_field->reset();
+ }
+ else
+ {
+ *copy->to_null_ptr&= ~copy->to_bit;
+ (copy->do_copy2)(copy);
+ }
+}
+
+/*
+ Copy: (not-NULL field in table that can be NULL-complemented) -> (NULLable
+ field)
+*/
+
+static void do_outer_field_null(Copy_field *copy)
+{
+ if (*copy->null_row ||
+ (copy->from_null_ptr && (*copy->from_null_ptr & copy->from_bit)))
+ {
+ *copy->to_null_ptr|=copy->to_bit;
+ copy->to_field->reset();
+ }
+ else
+ {
+ *copy->to_null_ptr&= ~copy->to_bit;
+ (copy->do_copy2)(copy);
+ }
+}
+
+/*
+ Copy: (not-NULL field in table that can be NULL-complemented) -> (not-NULL
+ field)
+*/
+static void do_copy_nullable_row_to_notnull(Copy_field *copy)
+{
+ if (*copy->null_row ||
+ (copy->from_null_ptr && (*copy->from_null_ptr & copy->from_bit)))
+ {
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ copy->to_field->reset();
+ }
+ else
+ {
+ (copy->do_copy2)(copy);
+ }
+
+}
+
+/* Copy: (NULL-able field) -> (not NULL-able field) */
+static void do_copy_not_null(Copy_field *copy)
+{
+ if (*copy->from_null_ptr & copy->from_bit)
+ {
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ copy->to_field->reset();
+ }
+ else
+ (copy->do_copy2)(copy);
+}
+
+
+/* Copy: (non-NULLable field) -> (NULLable field) */
+static void do_copy_maybe_null(Copy_field *copy)
+{
+ *copy->to_null_ptr&= ~copy->to_bit;
+ (copy->do_copy2)(copy);
+}
+
+/* timestamp and next_number has special handling in case of NULL values */
+
+static void do_copy_timestamp(Copy_field *copy)
+{
+ if (*copy->from_null_ptr & copy->from_bit)
+ {
+ /* Same as in set_field_to_null_with_conversions() */
+ copy->to_field->set_time();
+ }
+ else
+ (copy->do_copy2)(copy);
+}
+
+
+static void do_copy_next_number(Copy_field *copy)
+{
+ if (*copy->from_null_ptr & copy->from_bit)
+ {
+ /* Same as in set_field_to_null_with_conversions() */
+ copy->to_field->table->auto_increment_field_not_null= FALSE;
+ copy->to_field->reset();
+ }
+ else
+ (copy->do_copy2)(copy);
+}
+
+
+void Field_blob::do_copy_blob(Copy_field *copy)
+{
+ ((Field_blob*) copy->to_field)->copy_value(((Field_blob*) copy->from_field));
+}
+
+void Field_blob::do_conv_blob(Copy_field *copy)
+{
+ copy->from_field->val_str(&copy->tmp);
+ ((Field_blob *) copy->to_field)->store(copy->tmp.ptr(),
+ copy->tmp.length(),
+ copy->tmp.charset());
+}
+
+/** Save blob in copy->tmp for GROUP BY. */
+
+static void do_save_blob(Copy_field *copy)
+{
+ char buff[MAX_FIELD_WIDTH];
+ String res(buff,sizeof(buff),copy->tmp.charset());
+ copy->from_field->val_str(&res);
+ copy->tmp.copy(res);
+ ((Field_blob *) copy->to_field)->store(copy->tmp.ptr(),
+ copy->tmp.length(),
+ copy->tmp.charset());
+}
+
+
+void Field::do_field_string(Copy_field *copy)
+{
+ char buff[MAX_FIELD_WIDTH];
+ String res(buff, sizeof(buff), copy->from_field->charset());
+ res.length(0U);
+
+ copy->from_field->val_str(&res);
+ copy->to_field->store(res.c_ptr_quick(), res.length(), res.charset());
+}
+
+
+void Field_enum::do_field_enum(Copy_field *copy)
+{
+ if (copy->from_field->val_int() == 0)
+ ((Field_enum *) copy->to_field)->store_type((ulonglong) 0);
+ else
+ do_field_string(copy);
+}
+
+
+static void do_field_varbinary_pre50(Copy_field *copy)
+{
+ char buff[MAX_FIELD_WIDTH];
+ copy->tmp.set_quick(buff,sizeof(buff),copy->tmp.charset());
+ copy->from_field->val_str(&copy->tmp);
+
+ /* Use the same function as in 4.1 to trim trailing spaces */
+ size_t length= my_lengthsp_8bit(&my_charset_bin, copy->tmp.c_ptr_quick(),
+ copy->from_field->field_length);
+
+ copy->to_field->store(copy->tmp.c_ptr_quick(), length,
+ copy->tmp.charset());
+}
+
+
+void Field::do_field_int(Copy_field *copy)
+{
+ longlong value= copy->from_field->val_int();
+ copy->to_field->store(value,
+ MY_TEST(copy->from_field->flags & UNSIGNED_FLAG));
+}
+
+void Field::do_field_real(Copy_field *copy)
+{
+ double value=copy->from_field->val_real();
+ copy->to_field->store(value);
+}
+
+
+void Field::do_field_decimal(Copy_field *copy)
+{
+ my_decimal value(copy->from_field);
+ copy->to_field->store_decimal(&value);
+}
+
+
+void Field::do_field_timestamp(Copy_field *copy)
+{
+ // XXX why couldn't we do it everywhere?
+ copy->from_field->save_in_field(copy->to_field);
+}
+
+
+void Field::do_field_temporal(Copy_field *copy, date_mode_t fuzzydate)
+{
+ MYSQL_TIME ltime;
+ // TODO: we now need to check result
+ if (copy->from_field->get_date(&ltime, fuzzydate))
+ copy->to_field->reset();
+ else
+ copy->to_field->store_time_dec(&ltime, copy->from_field->decimals());
+}
+
+
+void Field::do_field_datetime(Copy_field *copy)
+{
+ return do_field_temporal(copy, Datetime::Options(TIME_CONV_NONE, current_thd));
+}
+
+
+void Field::do_field_date(Copy_field *copy)
+{
+ return do_field_temporal(copy, Date::Options(TIME_CONV_NONE));
+}
+
+
+void Field_time::do_field_time(Copy_field *copy)
+{
+ return do_field_temporal(copy, Time::Options(current_thd));
+}
+
+
+/**
+ string copy for single byte characters set when to string is shorter than
+ from string.
+*/
+
+static void do_cut_string(Copy_field *copy)
+{
+ CHARSET_INFO *cs= copy->from_field->charset();
+ memcpy(copy->to_ptr,copy->from_ptr,copy->to_length);
+
+ /* Check if we loosed any important characters */
+ if (cs->scan((char*) copy->from_ptr + copy->to_length,
+ (char*) copy->from_ptr + copy->from_length,
+ MY_SEQ_SPACES) < copy->from_length - copy->to_length)
+ {
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+}
+
+
+/**
+ string copy for multi byte characters set when to string is shorter than
+ from string.
+*/
+
+static void do_cut_string_complex(Copy_field *copy)
+{ // Shorter string field
+ CHARSET_INFO *cs= copy->from_field->charset();
+ const uchar *from_end= copy->from_ptr + copy->from_length;
+ Well_formed_prefix prefix(cs,
+ (char*) copy->from_ptr,
+ (char*) from_end,
+ copy->to_length / cs->mbmaxlen);
+ size_t copy_length= prefix.length();
+ if (copy->to_length < copy_length)
+ copy_length= copy->to_length;
+ memcpy(copy->to_ptr, copy->from_ptr, copy_length);
+
+ /* Check if we lost any important characters */
+ if (unlikely(prefix.well_formed_error_pos() ||
+ cs->scan((char*) copy->from_ptr + copy_length,
+ (char*) from_end,
+ MY_SEQ_SPACES) <
+ (copy->from_length - copy_length)))
+ {
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+
+ if (copy_length < copy->to_length)
+ cs->fill((char*) copy->to_ptr + copy_length,
+ copy->to_length - copy_length, ' ');
+}
+
+
+
+
+static void do_expand_binary(Copy_field *copy)
+{
+ CHARSET_INFO *cs= copy->from_field->charset();
+ memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);
+ cs->fill((char*) copy->to_ptr+copy->from_length,
+ copy->to_length-copy->from_length, '\0');
+}
+
+
+
+static void do_expand_string(Copy_field *copy)
+{
+ CHARSET_INFO *cs= copy->from_field->charset();
+ memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);
+ cs->fill((char*) copy->to_ptr+copy->from_length,
+ copy->to_length-copy->from_length, ' ');
+}
+
+
+static void do_varstring1(Copy_field *copy)
+{
+ uint length= (uint) *(uchar*) copy->from_ptr;
+ if (length > copy->to_length- 1)
+ {
+ length=copy->to_length - 1;
+ if (copy->from_field->table->in_use->count_cuted_fields >
+ CHECK_FIELD_EXPRESSION &&
+ copy->to_field)
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+ *(uchar*) copy->to_ptr= (uchar) length;
+ memcpy(copy->to_ptr+1, copy->from_ptr + 1, length);
+}
+
+
+static void do_varstring1_mb(Copy_field *copy)
+{
+ CHARSET_INFO *cs= copy->from_field->charset();
+ uint from_length= (uint) *(uchar*) copy->from_ptr;
+ const uchar *from_ptr= copy->from_ptr + 1;
+ uint to_char_length= (copy->to_length - 1) / cs->mbmaxlen;
+ Well_formed_prefix prefix(cs, (char*) from_ptr, from_length, to_char_length);
+ if (prefix.length() < from_length)
+ {
+ if (current_thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+ *copy->to_ptr= (uchar) prefix.length();
+ memcpy(copy->to_ptr + 1, from_ptr, prefix.length());
+}
+
+
+static void do_varstring2(Copy_field *copy)
+{
+ uint length=uint2korr(copy->from_ptr);
+ if (length > copy->to_length- HA_KEY_BLOB_LENGTH)
+ {
+ length=copy->to_length-HA_KEY_BLOB_LENGTH;
+ if (copy->from_field->table->in_use->count_cuted_fields >
+ CHECK_FIELD_EXPRESSION &&
+ copy->to_field)
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+ int2store(copy->to_ptr,length);
+ memcpy(copy->to_ptr+HA_KEY_BLOB_LENGTH, copy->from_ptr + HA_KEY_BLOB_LENGTH,
+ length);
+}
+
+
+static void do_varstring2_mb(Copy_field *copy)
+{
+ CHARSET_INFO *cs= copy->from_field->charset();
+ uint char_length= (copy->to_length - HA_KEY_BLOB_LENGTH) / cs->mbmaxlen;
+ uint from_length= uint2korr(copy->from_ptr);
+ const uchar *from_beg= copy->from_ptr + HA_KEY_BLOB_LENGTH;
+ Well_formed_prefix prefix(cs, (char*) from_beg, from_length, char_length);
+ if (prefix.length() < from_length)
+ {
+ if (current_thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
+ copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
+ WARN_DATA_TRUNCATED, 1);
+ }
+ int2store(copy->to_ptr, prefix.length());
+ memcpy(copy->to_ptr+HA_KEY_BLOB_LENGTH, from_beg, prefix.length());
+}
+
+
+/***************************************************************************
+** The different functions that fills in a Copy_field class
+***************************************************************************/
+
+/**
+ copy of field to maybe null string.
+ If field is null then the all bytes are set to 0.
+ if field is not null then the first byte is set to 1 and the rest of the
+ string is the field value.
+ The 'to' buffer should have a size of field->pack_length()+1
+*/
+
+void Copy_field::set(uchar *to,Field *from)
+{
+ from_ptr=from->ptr;
+ to_ptr=to;
+ from_length=from->pack_length_in_rec();
+ if (from->maybe_null())
+ {
+ from_null_ptr=from->null_ptr;
+ from_bit= from->null_bit;
+ to_ptr[0]= 1; // Null as default value
+ to_null_ptr= (uchar*) to_ptr++;
+ to_bit= 1;
+ if (from->table->maybe_null)
+ {
+ null_row= &from->table->null_row;
+ do_copy= do_outer_field_to_null_str;
+ }
+ else
+ do_copy= do_field_to_null_str;
+ }
+ else
+ {
+ to_null_ptr= 0; // For easy debugging
+ do_copy= Field::do_field_eq;
+ }
+}
+
+
+/*
+ To do:
+
+ If 'save' is set to true and the 'from' is a blob field, do_copy is set to
+ do_save_blob rather than do_conv_blob. The only differences between them
+ appears to be:
+
+ - do_save_blob allocates and uses an intermediate buffer before calling
+ Field_blob::store. Is this in order to trigger the call to
+ well_formed_copy_nchars, by changing the pointer copy->tmp.ptr()?
+ That call will take place anyway in all known cases.
+ */
+void Copy_field::set(Field *to,Field *from,bool save)
+{
+ if (to->type() == MYSQL_TYPE_NULL)
+ {
+ to_null_ptr=0; // For easy debugging
+ to_ptr=0;
+ do_copy=do_skip;
+ return;
+ }
+ from_field=from;
+ to_field=to;
+ from_ptr=from->ptr;
+ from_length=from->pack_length_in_rec();
+ to_ptr= to->ptr;
+ to_length=to_field->pack_length_in_rec();
+
+ // set up null handling
+ from_null_ptr=to_null_ptr=0;
+ if (from->maybe_null())
+ {
+ from_null_ptr= from->null_ptr;
+ from_bit= from->null_bit;
+ if (to_field->real_maybe_null())
+ {
+ to_null_ptr= to->null_ptr;
+ to_bit= to->null_bit;
+ if (from_null_ptr)
+ do_copy= do_copy_null;
+ else
+ {
+ null_row= &from->table->null_row;
+ do_copy= do_outer_field_null;
+ }
+ }
+ else
+ {
+ if (to_field->type() == MYSQL_TYPE_TIMESTAMP)
+ do_copy= do_copy_timestamp; // Automatic timestamp
+ else if (to_field == to_field->table->next_number_field)
+ do_copy= do_copy_next_number;
+ else
+ {
+ if (!from_null_ptr)
+ {
+ null_row= &from->table->null_row;
+ do_copy= do_copy_nullable_row_to_notnull;
+ }
+ else
+ do_copy= do_copy_not_null;
+ }
+ }
+ }
+ else if (to_field->real_maybe_null())
+ {
+ to_null_ptr= to->null_ptr;
+ to_bit= to->null_bit;
+ do_copy= do_copy_maybe_null;
+ }
+ else
+ do_copy=0;
+
+ if ((to->flags & BLOB_FLAG) && save)
+ do_copy2= do_save_blob;
+ else
+ do_copy2= from->get_copy_func_to(to);
+ if (!do_copy) // Not null
+ do_copy=do_copy2;
+}
+
+
+Field::Copy_func *Field_timestamp::get_copy_func(const Field *from) const
+{
+ Field::Copy_func *copy= Field_temporal::get_copy_func(from);
+ if (copy == do_field_datetime && from->type() == MYSQL_TYPE_TIMESTAMP)
+ return do_field_timestamp;
+ else
+ return copy;
+}
+
+
+Field::Copy_func *Field_date_common::get_copy_func(const Field *from) const
+{
+ Field::Copy_func *copy= Field_temporal::get_copy_func(from);
+ return copy == do_field_datetime ? do_field_date : copy;
+}
+
+
+Field::Copy_func *Field_temporal::get_copy_func(const Field *from) const
+{
+ /* If types are not 100 % identical then convert trough get_date() */
+ if (from->cmp_type() == REAL_RESULT)
+ return do_field_string; // TODO: MDEV-9344
+ if (from->type() == MYSQL_TYPE_YEAR)
+ return do_field_string; // TODO: MDEV-9343
+ if (from->type() == MYSQL_TYPE_BIT)
+ return do_field_int;
+ if (!eq_def(from) ||
+ (table->in_use->variables.sql_mode &
+ (MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE)))
+ return do_field_datetime;
+ return get_identical_copy_func();
+}
+
+
+Field::Copy_func *Field_varstring::get_copy_func(const Field *from) const
+{
+ if (from->type() == MYSQL_TYPE_BIT)
+ return do_field_int;
+ /*
+ Detect copy from pre 5.0 varbinary to varbinary as of 5.0 and
+ use special copy function that removes trailing spaces and thus
+ repairs data.
+ */
+ if (from->type() == MYSQL_TYPE_VAR_STRING && !from->has_charset() &&
+ !Field_varstring::has_charset())
+ return do_field_varbinary_pre50;
+ if (Field_varstring::real_type() != from->real_type() ||
+ Field_varstring::charset() != from->charset() ||
+ length_bytes != ((const Field_varstring*) from)->length_bytes ||
+ !compression_method() != !from->compression_method())
+ return do_field_string;
+ return length_bytes == 1 ?
+ (from->charset()->mbmaxlen == 1 ? do_varstring1 : do_varstring1_mb) :
+ (from->charset()->mbmaxlen == 1 ? do_varstring2 : do_varstring2_mb);
+}
+
+
+Field::Copy_func *Field_string::get_copy_func(const Field *from) const
+{
+ if (from->type() == MYSQL_TYPE_BIT)
+ return do_field_int;
+ if (Field_string::type_handler() != from->type_handler() ||
+ Field_string::charset() != from->charset())
+ return do_field_string;
+ if (Field_string::pack_length() < from->pack_length())
+ return (Field_string::charset()->mbmaxlen == 1 ?
+ do_cut_string : do_cut_string_complex);
+ if (Field_string::pack_length() > from->pack_length())
+ return Field_string::charset() == &my_charset_bin ? do_expand_binary :
+ do_expand_string;
+ return get_identical_copy_func();
+}
+
+
+Field::Copy_func *Field::get_identical_copy_func() const
+{
+ /* Identical field types */
+ switch (pack_length()) {
+ case 1: return do_field_1;
+ case 2: return do_field_2;
+ case 3: return do_field_3;
+ case 4: return do_field_4;
+ case 6: return do_field_6;
+ case 8: return do_field_8;
+ }
+ return do_field_eq;
+}
+
+
+bool Field_temporal::memcpy_field_possible(const Field *from) const
+{
+ return real_type() == from->real_type() &&
+ decimals() == from->decimals() &&
+ !sql_mode_for_dates(table->in_use);
+}
+
+
+static int field_conv_memcpy(Field *to, Field *from)
+{
+ /*
+ This may happen if one does 'UPDATE ... SET x=x'
+ The test is here mostly for valgrind, but can also be relevant
+ if memcpy() is implemented with prefetch-write
+ */
+ if (to->ptr != from->ptr)
+ memcpy(to->ptr,from->ptr, to->pack_length());
+ return 0;
+}
+
+
+/**
+ Copy value of the field with conversion.
+
+ @note Impossibility of simple copy should be checked before this call.
+
+ @param to The field to copy to
+
+ @retval TRUE ERROR
+ @retval FALSE OK
+
+*/
+static int field_conv_incompatible(Field *to, Field *from)
+{
+ return to->store_field(from);
+}
+
+
+/**
+ Simple quick field converter that is called on insert, e.g.:
+ INSERT INTO t1 (field1) SELECT field2 FROM t2;
+*/
+
+int field_conv(Field *to,Field *from)
+{
+ return to->memcpy_field_possible(from) ?
+ field_conv_memcpy(to, from) :
+ field_conv_incompatible(to, from);
+}
+
+
+fast_field_copier Field::get_fast_field_copier(const Field *from)
+{
+ DBUG_ENTER("Field::get_fast_field_copier");
+ DBUG_RETURN(memcpy_field_possible(from) ?
+ &field_conv_memcpy :
+ &field_conv_incompatible);
+}