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Editing: charset_collations.h
/* Copyright (c) 2023, 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 */ #ifndef LEX_CHARSET_COLLATIONS_INCLUDED #define LEX_CHARSET_COLLATIONS_INCLUDED #include "sql_used.h" struct Charset_collation_map_st { public: struct Elem_st { protected: CHARSET_INFO *m_from; // From a character set CHARSET_INFO *m_to; // To a collation static size_t print_lex_string(char *dst, const LEX_CSTRING &str) { memcpy(dst, str.str, str.length); return str.length; } public: /* Size in text format: 'utf8mb4=utf8mb4_unicode_ai_ci' */ static constexpr size_t text_size_max() { return MY_CS_CHARACTER_SET_NAME_SIZE + 1 + MY_CS_COLLATION_NAME_SIZE; } CHARSET_INFO *from() const { return m_from; } CHARSET_INFO *to() const { return m_to; } void set_to(CHARSET_INFO *cl) { m_to= cl; } size_t print(char *dst) const { const char *dst0= dst; dst+= print_lex_string(dst, m_from->cs_name); *dst++= '='; dst+= print_lex_string(dst, m_to->coll_name); return (size_t) (dst - dst0); } int cmp_by_charset_id(const Elem_st &rhs) const { return m_from->number < rhs.m_from->number ? -1 : m_from->number > rhs.m_from->number ? +1 : 0; } }; class Elem: public Elem_st { public: Elem(CHARSET_INFO *from, CHARSET_INFO *to) { m_from= from; m_to= to; } }; protected: Elem_st m_element[8]; // Should be enough for now uint m_count; uint m_version; static int cmp_by_charset_id(const void *a, const void *b) { return static_cast<const Elem_st*>(a)-> cmp_by_charset_id(*static_cast<const Elem_st*>(b)); } void sort() { qsort(m_element, m_count, sizeof(Elem_st), cmp_by_charset_id); } const Elem_st *find_elem_by_charset_id(uint id) const { if (!m_count) return NULL; int first= 0, last= ((int) m_count) - 1; for ( ; first <= last; ) { const int middle= (first + last) / 2; DBUG_ASSERT(middle >= 0); DBUG_ASSERT(middle < (int) m_count); const uint middle_id= m_element[middle].from()->number; if (middle_id == id) return &m_element[middle]; if (middle_id < id) first= middle + 1; else last= middle - 1; } return NULL; } bool insert(const Elem_st &elem) { DBUG_ASSERT(elem.from()->state & MY_CS_PRIMARY); if (m_count >= array_elements(m_element)) return true; m_element[m_count]= elem; m_count++; sort(); return false; } bool insert_or_replace(const Elem_st &elem) { DBUG_ASSERT(elem.from()->state & MY_CS_PRIMARY); const Elem_st *found= find_elem_by_charset_id(elem.from()->number); if (found) { const_cast<Elem_st*>(found)->set_to(elem.to()); return false; } return insert(elem); } public: void init() { m_count= 0; m_version= 0; } uint count() const { return m_count; } uint version() const { return m_version; } void set(const Charset_collation_map_st &rhs, uint version_increment) { uint version= m_version; *this= rhs; m_version= version + version_increment; } const Elem_st & operator[](uint pos) const { DBUG_ASSERT(pos < m_count); return m_element[pos]; } bool insert_or_replace(const class Lex_exact_charset &cs, const class Lex_extended_collation &cl, bool error_on_conflicting_duplicate); bool insert_or_replace(const LEX_CSTRING &cs, const LEX_CSTRING &cl, bool error_on_conflicting_duplicate, myf utf8_flag); CHARSET_INFO *get_collation_for_charset(Sql_used *used, CHARSET_INFO *cs) const { DBUG_ASSERT(cs->state & MY_CS_PRIMARY); const Elem_st *elem= find_elem_by_charset_id(cs->number); used->used|= Sql_used::CHARACTER_SET_COLLATIONS_USED; if (elem) return elem->to(); return cs; } size_t text_format_nbytes_needed() const { return (Elem_st::text_size_max() + 1/* for ',' */) * m_count; } size_t print(char *dst, size_t nbytes_available) const { const char *dst0= dst; const char *end= dst + nbytes_available; for (uint i= 0; i < m_count; i++) { if (Elem_st::text_size_max() + 1/* for ',' */ > (size_t) (end - dst)) break; if (i > 0) *dst++= ','; dst+= m_element[i].print(dst); } return dst - dst0; } static constexpr size_t binary_size_max() { return 1/*count*/ + 4 * array_elements(m_element); } size_t to_binary(char *dst) const { const char *dst0= dst; *dst++= (char) (uchar) m_count; for (uint i= 0; i < m_count; i++) { int2store(dst, (uint16) m_element[i].from()->number); dst+= 2; int2store(dst, (uint16) m_element[i].to()->number); dst+= 2; } return (size_t) (dst - dst0); } size_t from_binary(const char *src, size_t srclen) { const char *src0= src; init(); if (!srclen) return 0; // Empty uint count= (uchar) *src++; if (srclen < 1 + 4 * count) return 0; for (uint i= 0; i < count; i++, src+= 4) { CHARSET_INFO *cs, *cl; if (!(cs= get_charset(uint2korr(src), MYF(0))) || !(cl= get_charset(uint2korr(src + 2), MYF(0)))) { /* Unpacking from binary format happens on the slave side. If for some reasons the slave does not know about a character set or a collation, just skip the pair here. This pair might not even be needed. */ continue; } insert_or_replace(Elem(cs, cl)); } return src - src0; } bool from_text(const LEX_CSTRING &str, myf utf8_flag); }; #endif // LEX_CHARSET_COLLATIONS_INCLUDED
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