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diff --git a/sql/sql_help.cc b/sql/sql_help.cc
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+/* Copyright (c) 2002, 2012, Oracle and/or its affiliates.
+
+ 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 Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#include "mariadb.h"
+#include "sql_priv.h"
+#include "unireg.h"
+#include "sql_help.h"
+#include "sql_table.h" // primary_key_name
+#include "sql_base.h" // REPORT_ALL_ERRORS, setup_tables
+#include "opt_range.h" // SQL_SELECT
+#include "records.h" // init_read_record, end_read_record
+
+struct st_find_field
+{
+ const char *table_name, *field_name;
+ Field *field;
+};
+
+/* Used fields */
+
+static struct st_find_field init_used_fields[]=
+{
+ { "help_topic", "help_topic_id", 0},
+ { "help_topic", "name", 0},
+ { "help_topic", "help_category_id", 0},
+ { "help_topic", "description", 0},
+ { "help_topic", "example", 0},
+
+ { "help_category", "help_category_id", 0},
+ { "help_category", "parent_category_id", 0},
+ { "help_category", "name", 0},
+
+ { "help_keyword", "help_keyword_id", 0},
+ { "help_keyword", "name", 0},
+
+ { "help_relation", "help_topic_id", 0},
+ { "help_relation", "help_keyword_id", 0}
+};
+
+enum enum_used_fields
+{
+ help_topic_help_topic_id= 0,
+ help_topic_name,
+ help_topic_help_category_id,
+ help_topic_description,
+ help_topic_example,
+
+ help_category_help_category_id,
+ help_category_parent_category_id,
+ help_category_name,
+
+ help_keyword_help_keyword_id,
+ help_keyword_name,
+
+ help_relation_help_topic_id,
+ help_relation_help_keyword_id
+};
+
+
+/*
+ Fill st_find_field structure with pointers to fields
+
+ SYNOPSIS
+ init_fields()
+ thd Thread handler
+ tables list of all tables for fields
+ find_fields array of structures
+ count size of previous array
+
+ RETURN VALUES
+ 0 all ok
+ 1 one of the fileds was not found
+*/
+
+static bool init_fields(THD *thd, TABLE_LIST *tables,
+ struct st_find_field *find_fields, uint count)
+{
+ Name_resolution_context *context= &thd->lex->first_select_lex()->context;
+ DBUG_ENTER("init_fields");
+ context->resolve_in_table_list_only(tables);
+ for (; count-- ; find_fields++)
+ {
+ /* We have to use 'new' here as field will be re_linked on free */
+ Item_field *field= (new (thd->mem_root)
+ Item_field(thd, context,
+ {STRING_WITH_LEN("mysql")},
+ Lex_cstring_strlen(find_fields->table_name),
+ Lex_cstring_strlen(find_fields->field_name)));
+ if (!(find_fields->field= find_field_in_tables(thd, field, tables, NULL,
+ 0, REPORT_ALL_ERRORS, 1,
+ TRUE)))
+ DBUG_RETURN(1);
+ bitmap_set_bit(find_fields->field->table->read_set,
+ find_fields->field->field_index);
+ /* To make life easier when setting values in keys */
+ bitmap_set_bit(find_fields->field->table->write_set,
+ find_fields->field->field_index);
+ }
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Returns variants of found topic for help (if it is just single topic,
+ returns description and example, or else returns only names..)
+
+ SYNOPSIS
+ memorize_variant_topic()
+
+ thd Thread handler
+ topics Table of topics
+ count number of alredy found topics
+ find_fields Filled array of information for work with fields
+
+ RETURN VALUES
+ names array of names of found topics (out)
+
+ name name of found topic (out)
+ description description of found topic (out)
+ example example for found topic (out)
+
+ NOTE
+ Field 'names' is set only if more than one topic is found.
+ Fields 'name', 'description', 'example' are set only if
+ found exactly one topic.
+*/
+
+void memorize_variant_topic(THD *thd, TABLE *topics, int count,
+ struct st_find_field *find_fields,
+ List<String> *names,
+ String *name, String *description, String *example)
+{
+ DBUG_ENTER("memorize_variant_topic");
+ MEM_ROOT *mem_root= thd->mem_root;
+ if (count==0)
+ {
+ get_field(mem_root,find_fields[help_topic_name].field, name);
+ get_field(mem_root,find_fields[help_topic_description].field, description);
+ get_field(mem_root,find_fields[help_topic_example].field, example);
+ }
+ else
+ {
+ if (count == 1)
+ names->push_back(name, thd->mem_root);
+ String *new_name= new (thd->mem_root) String;
+ get_field(mem_root,find_fields[help_topic_name].field,new_name);
+ names->push_back(new_name, thd->mem_root);
+ }
+ DBUG_VOID_RETURN;
+}
+
+/*
+ Look for topics by mask
+
+ SYNOPSIS
+ search_topics()
+ thd Thread handler
+ topics Table of topics
+ find_fields Filled array of info for fields
+ select Function to test for matching help topic.
+ Normally 'help_topic.name like 'bit%'
+
+ RETURN VALUES
+ # number of topics found
+
+ names array of names of found topics (out)
+ name name of found topic (out)
+ description description of found topic (out)
+ example example for found topic (out)
+
+ NOTE
+ Field 'names' is set only if more than one topic was found.
+ Fields 'name', 'description', 'example' are set only if
+ exactly one topic was found.
+
+*/
+
+int search_topics(THD *thd, TABLE *topics, struct st_find_field *find_fields,
+ SQL_SELECT *select, List<String> *names,
+ String *name, String *description, String *example)
+{
+ int count= 0;
+ READ_RECORD read_record_info;
+ DBUG_ENTER("search_topics");
+
+ /* Should never happen. As this is part of help, we can ignore this */
+ if (init_read_record(&read_record_info, thd, topics, select, NULL, 1, 0,
+ FALSE))
+ DBUG_RETURN(0);
+
+ while (!read_record_info.read_record())
+ {
+ if (!select->cond->val_int()) // Doesn't match like
+ continue;
+ memorize_variant_topic(thd,topics,count,find_fields,
+ names,name,description,example);
+ count++;
+ }
+ end_read_record(&read_record_info);
+
+ DBUG_RETURN(count);
+}
+
+/*
+ Look for keyword by mask
+
+ SYNOPSIS
+ search_keyword()
+ thd Thread handler
+ keywords Table of keywords
+ find_fields Filled array of info for fields
+ select Function to test for matching keyword.
+ Normally 'help_keyword.name like 'bit%'
+
+ key_id help_keyword_if of found topics (out)
+
+ RETURN VALUES
+ 0 didn't find any topics matching the mask
+ 1 found exactly one topic matching the mask
+ 2 found more then one topic matching the mask
+*/
+
+int search_keyword(THD *thd, TABLE *keywords,
+ struct st_find_field *find_fields,
+ SQL_SELECT *select, int *key_id)
+{
+ int count= 0;
+ READ_RECORD read_record_info;
+ DBUG_ENTER("search_keyword");
+ /* Should never happen. As this is part of help, we can ignore this */
+ if (init_read_record(&read_record_info, thd, keywords, select, NULL, 1, 0,
+ FALSE))
+ DBUG_RETURN(0);
+
+ while (!read_record_info.read_record() && count<2)
+ {
+ if (!select->cond->val_int()) // Dosn't match like
+ continue;
+
+ *key_id= (int)find_fields[help_keyword_help_keyword_id].field->val_int();
+
+ count++;
+ }
+ end_read_record(&read_record_info);
+
+ DBUG_RETURN(count);
+}
+
+/*
+ Look for all topics with keyword
+
+ SYNOPSIS
+ get_topics_for_keyword()
+ thd Thread handler
+ topics Table of topics
+ relations Table of m:m relation "topic/keyword"
+ find_fields Filled array of info for fields
+ key_id Primary index to use to find for keyword
+
+ RETURN VALUES
+ # number of topics found
+
+ names array of name of found topics (out)
+
+ name name of found topic (out)
+ description description of found topic (out)
+ example example for found topic (out)
+
+ NOTE
+ Field 'names' is set only if more than one topic was found.
+ Fields 'name', 'description', 'example' are set only if
+ exactly one topic was found.
+*/
+
+int get_topics_for_keyword(THD *thd, TABLE *topics, TABLE *relations,
+ struct st_find_field *find_fields, int16 key_id,
+ List<String> *names,
+ String *name, String *description, String *example)
+{
+ uchar buff[8]; // Max int length
+ int count= 0;
+ int iindex_topic, iindex_relations;
+ Field *rtopic_id, *rkey_id;
+ DBUG_ENTER("get_topics_for_keyword");
+
+ if ((iindex_topic=
+ find_type(primary_key_name, &topics->s->keynames,
+ FIND_TYPE_NO_PREFIX) - 1) < 0 ||
+ (iindex_relations=
+ find_type(primary_key_name, &relations->s->keynames,
+ FIND_TYPE_NO_PREFIX) - 1) < 0)
+ {
+ my_message(ER_CORRUPT_HELP_DB, ER_THD(thd, ER_CORRUPT_HELP_DB), MYF(0));
+ DBUG_RETURN(-1);
+ }
+ rtopic_id= find_fields[help_relation_help_topic_id].field;
+ rkey_id= find_fields[help_relation_help_keyword_id].field;
+
+ if (topics->file->ha_index_init(iindex_topic,1) ||
+ relations->file->ha_index_init(iindex_relations,1))
+ {
+ if (topics->file->inited)
+ topics->file->ha_index_end();
+ my_message(ER_CORRUPT_HELP_DB, ER_THD(thd, ER_CORRUPT_HELP_DB), MYF(0));
+ DBUG_RETURN(-1);
+ }
+
+ rkey_id->store((longlong) key_id, TRUE);
+ rkey_id->get_key_image(buff, rkey_id->pack_length(), Field::itRAW);
+ int key_res= relations->file->ha_index_read_map(relations->record[0],
+ buff, (key_part_map) 1,
+ HA_READ_KEY_EXACT);
+
+ for ( ;
+ !key_res && key_id == (int16) rkey_id->val_int() ;
+ key_res= relations->file->ha_index_next(relations->record[0]))
+ {
+ uchar topic_id_buff[8];
+ longlong topic_id= rtopic_id->val_int();
+ Field *field= find_fields[help_topic_help_topic_id].field;
+ field->store((longlong) topic_id, TRUE);
+ field->get_key_image(topic_id_buff, field->pack_length(), Field::itRAW);
+
+ if (!topics->file->ha_index_read_map(topics->record[0], topic_id_buff,
+ (key_part_map)1, HA_READ_KEY_EXACT))
+ {
+ memorize_variant_topic(thd,topics,count,find_fields,
+ names,name,description,example);
+ count++;
+ }
+ }
+ topics->file->ha_index_end();
+ relations->file->ha_index_end();
+ DBUG_RETURN(count);
+}
+
+/*
+ Look for categories by mask
+
+ SYNOPSIS
+ search_categories()
+ thd THD for init_read_record
+ categories Table of categories
+ find_fields Filled array of info for fields
+ select Function to test for if matching help topic.
+ Normally 'help_vategory.name like 'bit%'
+ names List of found categories names (out)
+ res_id Primary index of found category (only if
+ found exactly one category)
+
+ RETURN VALUES
+ # Number of categories found
+*/
+
+int search_categories(THD *thd, TABLE *categories,
+ struct st_find_field *find_fields,
+ SQL_SELECT *select, List<String> *names, int16 *res_id)
+{
+ Field *pfname= find_fields[help_category_name].field;
+ Field *pcat_id= find_fields[help_category_help_category_id].field;
+ int count= 0;
+ READ_RECORD read_record_info;
+ DBUG_ENTER("search_categories");
+
+ /* Should never happen. As this is part of help, we can ignore this */
+ if (init_read_record(&read_record_info, thd, categories, select, NULL,
+ 1, 0, FALSE))
+ DBUG_RETURN(0);
+ while (!read_record_info.read_record())
+ {
+ if (select && !select->cond->val_int())
+ continue;
+ String *lname= new (thd->mem_root) String;
+ get_field(thd->mem_root,pfname,lname);
+ if (++count == 1 && res_id)
+ *res_id= (int16) pcat_id->val_int();
+ names->push_back(lname, thd->mem_root);
+ }
+ end_read_record(&read_record_info);
+
+ DBUG_RETURN(count);
+}
+
+/*
+ Look for all topics or subcategories of category
+
+ SYNOPSIS
+ get_all_items_for_category()
+ thd Thread handler
+ items Table of items
+ pfname Field "name" in items
+ select "where" part of query..
+ res list of finded names
+*/
+
+void get_all_items_for_category(THD *thd, TABLE *items, Field *pfname,
+ SQL_SELECT *select, List<String> *res)
+{
+ READ_RECORD read_record_info;
+ DBUG_ENTER("get_all_items_for_category");
+
+ /* Should never happen. As this is part of help, we can ignore this */
+ if (init_read_record(&read_record_info, thd, items, select, NULL, 1, 0,
+ FALSE))
+ DBUG_VOID_RETURN;
+
+ while (!read_record_info.read_record())
+ {
+ if (!select->cond->val_int())
+ continue;
+ String *name= new (thd->mem_root) String();
+ get_field(thd->mem_root,pfname,name);
+ res->push_back(name, thd->mem_root);
+ }
+ end_read_record(&read_record_info);
+
+ DBUG_VOID_RETURN;
+}
+
+/*
+ Send to client answer for help request
+
+ SYNOPSIS
+ send_answer_1()
+ protocol - protocol for sending
+ s1 - value of column "Name"
+ s2 - value of column "Description"
+ s3 - value of column "Example"
+
+ IMPLEMENTATION
+ Format used:
+ +----------+------------+------------+
+ |name |description |example |
+ +----------+------------+------------+
+ |String(64)|String(1000)|String(1000)|
+ +----------+------------+------------+
+ with exactly one row!
+
+ RETURN VALUES
+ 1 Writing of head failed
+ -1 Writing of row failed
+ 0 Successeful send
+*/
+
+int send_answer_1(Protocol *protocol, String *s1, String *s2, String *s3)
+{
+ THD *thd= protocol->thd;
+ MEM_ROOT *mem_root= thd->mem_root;
+ DBUG_ENTER("send_answer_1");
+
+ List<Item> field_list;
+ field_list.push_back(new (mem_root) Item_empty_string(thd, "name", 64),
+ mem_root);
+ field_list.push_back(new (mem_root) Item_empty_string(thd, "description", 1000),
+ mem_root);
+ field_list.push_back(new (mem_root) Item_empty_string(thd, "example", 1000),
+ mem_root);
+
+ if (protocol->send_result_set_metadata(&field_list,
+ Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF))
+ DBUG_RETURN(1);
+
+ protocol->prepare_for_resend();
+ protocol->store(s1);
+ protocol->store(s2);
+ protocol->store(s3);
+ if (protocol->write())
+ DBUG_RETURN(-1);
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Send to client help header
+
+ SYNOPSIS
+ send_header_2()
+ protocol - protocol for sending
+ is_it_category - need column 'source_category_name'
+
+ IMPLEMENTATION
+ +- -+
+ |+-------------------- | +----------+--------------+
+ ||source_category_name | |name |is_it_category|
+ |+-------------------- | +----------+--------------+
+ ||String(64) | |String(64)|String(1) |
+ |+-------------------- | +----------+--------------+
+ +- -+
+
+ RETURN VALUES
+ result of protocol->send_result_set_metadata
+*/
+
+int send_header_2(Protocol *protocol, bool for_category)
+{
+ THD *thd= protocol->thd;
+ MEM_ROOT *mem_root= thd->mem_root;
+ DBUG_ENTER("send_header_2");
+ List<Item> field_list;
+ if (for_category)
+ field_list.push_back(new (mem_root)
+ Item_empty_string(thd, "source_category_name", 64),
+ mem_root);
+ field_list.push_back(new (mem_root)
+ Item_empty_string(thd, "name", 64),
+ mem_root);
+ field_list.push_back(new (mem_root)
+ Item_empty_string(thd, "is_it_category", 1),
+ mem_root);
+ DBUG_RETURN(protocol->send_result_set_metadata(&field_list,
+ Protocol::SEND_NUM_ROWS |
+ Protocol::SEND_EOF));
+}
+
+/*
+ strcmp for using in qsort
+
+ SYNOPSIS
+ strptrcmp()
+ ptr1 (const void*)&str1
+ ptr2 (const void*)&str2
+
+ RETURN VALUES
+ same as strcmp
+*/
+
+extern "C" int string_ptr_cmp(const void* ptr1, const void* ptr2)
+{
+ String *str1= *(String**)ptr1;
+ String *str2= *(String**)ptr2;
+ return strcmp(str1->c_ptr(),str2->c_ptr());
+}
+
+/*
+ Send to client rows in format:
+ column1 : <name>
+ column2 : <is_it_category>
+
+ SYNOPSIS
+ send_variant_2_list()
+ protocol Protocol for sending
+ names List of names
+ cat Value of the column <is_it_category>
+ source_name name of category for all items..
+
+ RETURN VALUES
+ -1 Writing fail
+ 0 Data was successefully send
+*/
+
+int send_variant_2_list(MEM_ROOT *mem_root, Protocol *protocol,
+ List<String> *names,
+ const char *cat, String *source_name)
+{
+ DBUG_ENTER("send_variant_2_list");
+
+ String **pointers= (String**)alloc_root(mem_root,
+ sizeof(String*)*names->elements);
+ String **pos;
+ String **end= pointers + names->elements;
+
+ List_iterator<String> it(*names);
+ for (pos= pointers; pos!=end; (*pos++= it++))
+ ;
+
+ my_qsort(pointers,names->elements,sizeof(String*),string_ptr_cmp);
+
+ for (pos= pointers; pos!=end; pos++)
+ {
+ protocol->prepare_for_resend();
+ if (source_name)
+ protocol->store(source_name);
+ protocol->store(*pos);
+ protocol->store(cat,1,&my_charset_latin1);
+ if (protocol->write())
+ DBUG_RETURN(-1);
+ }
+
+ DBUG_RETURN(0);
+}
+
+/*
+ Prepare simple SQL_SELECT table.* WHERE <Item>
+
+ SYNOPSIS
+ prepare_simple_select()
+ thd Thread handler
+ cond WHERE part of select
+ table goal table
+
+ error code of error (out)
+
+ RETURN VALUES
+ # created SQL_SELECT
+*/
+
+SQL_SELECT *prepare_simple_select(THD *thd, Item *cond,
+ TABLE *table, int *error)
+{
+ cond->fix_fields_if_needed(thd, &cond); // can never fail
+
+ /* Assume that no indexes cover all required fields */
+ table->covering_keys.clear_all();
+
+ SQL_SELECT *res= make_select(table, 0, 0, cond, 0, 0, error);
+ if (unlikely(*error) ||
+ (likely(res) && unlikely(res->check_quick(thd, 0, HA_POS_ERROR))) ||
+ (likely(res) && res->quick && unlikely(res->quick->reset())))
+ {
+ delete res;
+ res=0;
+ }
+ return res;
+}
+
+/*
+ Prepare simple SQL_SELECT table.* WHERE table.name LIKE mask
+
+ SYNOPSIS
+ prepare_select_for_name()
+ thd Thread handler
+ mask mask for compare with name
+ mlen length of mask
+ tables list of tables, used in WHERE
+ table goal table
+ pfname field "name" in table
+
+ error code of error (out)
+
+ RETURN VALUES
+ # created SQL_SELECT
+*/
+
+SQL_SELECT *prepare_select_for_name(THD *thd, const char *mask, size_t mlen,
+ TABLE_LIST *tables, TABLE *table,
+ Field *pfname, int *error)
+{
+ MEM_ROOT *mem_root= thd->mem_root;
+ Item *cond= new (mem_root)
+ Item_func_like(thd,
+ new (mem_root)
+ Item_field(thd, pfname),
+ new (mem_root) Item_string(thd, mask, (uint)mlen,
+ pfname->charset()),
+ new (mem_root) Item_string_ascii(thd, "\\"),
+ FALSE);
+ if (unlikely(thd->is_fatal_error))
+ return 0; // OOM
+ return prepare_simple_select(thd, cond, table, error);
+}
+
+
+/*
+ Server-side function 'help'
+
+ SYNOPSIS
+ mysqld_help()
+ thd Thread handler
+
+ RETURN VALUES
+ FALSE Success
+ TRUE Error and send_error already committed
+*/
+
+static bool mysqld_help_internal(THD *thd, const char *mask)
+{
+ Protocol *protocol= thd->protocol;
+ SQL_SELECT *select;
+ st_find_field used_fields[array_elements(init_used_fields)];
+ List<TABLE_LIST> leaves;
+ TABLE_LIST tables[4];
+ List<String> topics_list, categories_list, subcategories_list;
+ String name, description, example;
+ int count_topics, count_categories, error;
+ size_t mlen= strlen(mask);
+ size_t i;
+ MEM_ROOT *mem_root= thd->mem_root;
+ LEX_CSTRING MYSQL_HELP_TOPIC_NAME= {STRING_WITH_LEN("help_topic") };
+ LEX_CSTRING MYSQL_HELP_CATEGORY_NAME= {STRING_WITH_LEN("help_category") };
+ LEX_CSTRING MYSQL_HELP_RELATION_NAME= {STRING_WITH_LEN("help_relation") };
+ LEX_CSTRING MYSQL_HELP_KEYWORD_NAME= {STRING_WITH_LEN("help_keyword") };
+ DBUG_ENTER("mysqld_help");
+
+ tables[0].init_one_table(&MYSQL_SCHEMA_NAME, &MYSQL_HELP_TOPIC_NAME, 0, TL_READ);
+ tables[1].init_one_table(&MYSQL_SCHEMA_NAME, &MYSQL_HELP_CATEGORY_NAME, 0, TL_READ);
+ tables[2].init_one_table(&MYSQL_SCHEMA_NAME, &MYSQL_HELP_RELATION_NAME, 0, TL_READ);
+ tables[3].init_one_table(&MYSQL_SCHEMA_NAME, &MYSQL_HELP_KEYWORD_NAME, 0, TL_READ);
+ tables[0].next_global= tables[0].next_local=
+ tables[0].next_name_resolution_table= &tables[1];
+ tables[1].next_global= tables[1].next_local=
+ tables[1].next_name_resolution_table= &tables[2];
+ tables[2].next_global= tables[2].next_local=
+ tables[2].next_name_resolution_table= &tables[3];
+
+ /*
+ HELP must be available under LOCK TABLES.
+ Reset and backup the current open tables state to
+ make it possible.
+ */
+ start_new_trans new_trans(thd);
+
+ if (open_system_tables_for_read(thd, tables))
+ goto error2;
+
+ /*
+ Init tables and fields to be usable from items
+ tables do not contain VIEWs => we can pass 0 as conds
+ */
+ thd->lex->first_select_lex()->context.table_list=
+ thd->lex->first_select_lex()->context.first_name_resolution_table=
+ &tables[0];
+ if (setup_tables(thd, &thd->lex->first_select_lex()->context,
+ &thd->lex->first_select_lex()->top_join_list,
+ tables, leaves, FALSE, FALSE))
+ goto error;
+ memcpy((char*) used_fields, (char*) init_used_fields, sizeof(used_fields));
+ if (init_fields(thd, tables, used_fields, array_elements(used_fields)))
+ goto error;
+ for (i=0; i<sizeof(tables)/sizeof(TABLE_LIST); i++)
+ tables[i].table->file->init_table_handle_for_HANDLER();
+
+ if (!(select=
+ prepare_select_for_name(thd,mask,mlen,tables,tables[0].table,
+ used_fields[help_topic_name].field,&error)))
+ goto error;
+
+ count_topics= search_topics(thd,tables[0].table,used_fields,
+ select,&topics_list,
+ &name, &description, &example);
+ delete select;
+
+ if (thd->is_error())
+ goto error;
+
+ if (count_topics == 0)
+ {
+ int UNINIT_VAR(key_id);
+ if (!(select=
+ prepare_select_for_name(thd,mask,mlen,tables,tables[3].table,
+ used_fields[help_keyword_name].field,
+ &error)))
+ goto error;
+
+ count_topics= search_keyword(thd,tables[3].table, used_fields, select,
+ &key_id);
+ delete select;
+ count_topics= (count_topics != 1) ? 0 :
+ get_topics_for_keyword(thd,tables[0].table,tables[2].table,
+ used_fields,key_id,&topics_list,&name,
+ &description,&example);
+ }
+
+ if (count_topics == 0)
+ {
+ int16 category_id;
+ Field *cat_cat_id= used_fields[help_category_parent_category_id].field;
+ if (!(select=
+ prepare_select_for_name(thd,mask,mlen,tables,tables[1].table,
+ used_fields[help_category_name].field,
+ &error)))
+ goto error;
+
+ count_categories= search_categories(thd, tables[1].table, used_fields,
+ select,
+ &categories_list,&category_id);
+ delete select;
+ if (!count_categories)
+ {
+ if (send_header_2(protocol,FALSE))
+ goto error;
+ }
+ else if (count_categories > 1)
+ {
+ if (send_header_2(protocol,FALSE) ||
+ send_variant_2_list(mem_root,protocol,&categories_list,"Y",0))
+ goto error;
+ }
+ else
+ {
+ Field *topic_cat_id= used_fields[help_topic_help_category_id].field;
+ Item *cond_topic_by_cat=
+ new (mem_root)
+ Item_func_equal(thd,
+ new (mem_root)
+ Item_field(thd, topic_cat_id),
+ new (mem_root)
+ Item_int(thd, (int32) category_id));
+ Item *cond_cat_by_cat=
+ new (mem_root)
+ Item_func_equal(thd,
+ new (mem_root) Item_field(thd, cat_cat_id),
+ new (mem_root) Item_int(thd, (int32) category_id));
+ if (!(select= prepare_simple_select(thd, cond_topic_by_cat,
+ tables[0].table, &error)))
+ goto error;
+ get_all_items_for_category(thd,tables[0].table,
+ used_fields[help_topic_name].field,
+ select,&topics_list);
+ delete select;
+ if (!(select= prepare_simple_select(thd, cond_cat_by_cat,
+ tables[1].table, &error)))
+ goto error;
+ get_all_items_for_category(thd,tables[1].table,
+ used_fields[help_category_name].field,
+ select,&subcategories_list);
+ delete select;
+ String *cat= categories_list.head();
+ if (send_header_2(protocol, TRUE) ||
+ send_variant_2_list(mem_root,protocol,&topics_list, "N",cat) ||
+ send_variant_2_list(mem_root,protocol,&subcategories_list,"Y",cat))
+ goto error;
+ }
+ }
+ else if (count_topics == 1)
+ {
+ if (send_answer_1(protocol,&name,&description,&example))
+ goto error;
+ }
+ else
+ {
+ /* First send header and functions */
+ if (send_header_2(protocol, FALSE) ||
+ send_variant_2_list(mem_root,protocol, &topics_list, "N", 0))
+ goto error;
+ if (!(select=
+ prepare_select_for_name(thd,mask,mlen,tables,tables[1].table,
+ used_fields[help_category_name].field,&error)))
+ goto error;
+ search_categories(thd, tables[1].table, used_fields,
+ select,&categories_list, 0);
+ delete select;
+ /* Then send categories */
+ if (send_variant_2_list(mem_root,protocol, &categories_list, "Y", 0))
+ goto error;
+ }
+ my_eof(thd);
+
+ thd->commit_whole_transaction_and_close_tables();
+ new_trans.restore_old_transaction();
+ DBUG_RETURN(FALSE);
+
+error:
+ thd->commit_whole_transaction_and_close_tables();
+ new_trans.restore_old_transaction();
+
+error2:
+ DBUG_RETURN(TRUE);
+}
+
+
+bool mysqld_help(THD *thd, const char *mask)
+{
+ Sql_mode_instant_remove sms(thd, MODE_PAD_CHAR_TO_FULL_LENGTH);
+ bool rc= mysqld_help_internal(thd, mask);
+ return rc;
+}