WL#2575 - Fulltext: Parser plugin for FTS

Manual merge.


Makefile.am:
  Added new 'plugin' subdir.
configure.in:
  Added plugin related makefiles.
include/my_base.h:
  Added HA_OPEN_FROM_SQL_LAYER flag - indicates that a table was openned from the sql layer.
  Added HA_OPTION_RELIES_ON_SQL_LAYER flag - indicates that a table relies on the sql layer.
  Added HA_CREATE_RELIES_ON_SQL_LAYER flag - indicates that a table must be created with
  HA_OPTION_RELIES_ON_SQL_LAYER flag.
include/myisam.h:
  Distinct fulltext parser number added.
include/plugin.h:
  Revise comment.
sql/ha_myisam.cc:
  Pass HA_OPEN_FROM_SQL_LAYER flag to mi_open().
  Pass HA_CREATE_RELIES_ON_SQL_LAYER flag to mi_create().
sql/sql_plugin.cc:
  Reuse "unused" dynamic array elements.
  A check for plugin info interface version.
sql/sql_plugin.h:
  Added plugin_type_names[] - string plugin type names.
sql/sql_show.cc:
  Use plugin_type_names array instead of switch to find literal parser name representation.
sql/sql_table.cc:
  Fixed that ALTER TABLE ... ADD INDEX loses WITH PARSER info.
storage/myisam/ft_boolean_search.c:
  Call fulltext parser init() function, pass MYSQL_FTPARSER_PARAM, returned by
  ftparser_call_initializer(), to parser->parse().
storage/myisam/ft_nlq_search.c:
  Call fulltext parser init() function, pass MYSQL_FTPARSER_PARAM, returned by
  ftparser_call_initializer(), to parser->parse().
storage/myisam/ft_parser.c:
  Added two functions:
  ftparser_call_initializer() - calls parser->init() function if specified and parser is not yet
  initialized. Returns MYSQL_FTPARSER_PARAM *.
  ftparser_call_deinitializer() - calls parser->deinit() function if specified and parser was
  initialized. Deinitializes all parsers.
  ft_parse() accepts additional param now - MYSQL_FTPARSER_PARM and passes it to parser->parse().
storage/myisam/ft_update.c:
  Call fulltext parser init() function, pass MYSQL_FTPARSER_PARAM, returned by
  ftparser_call_initializer(), to _mi_ft_parse().
  _mi_ft_parse() accepts additional param now - MYSQL_FTPARSER_PARAM and passes
  it to parser->parse().
storage/myisam/ftdefs.h:
  Prototypes for new functions were added. MYSQL_FTPARSER_PARAM was added
  to ft_parse and _mi_ft_parse().
storage/myisam/mi_close.c:
  Free ftparser_param allocated by ftparser_call_initializer().
storage/myisam/mi_create.c:
  If a table relies on the sql layer, set HA_OPTION_RELIES_ON_SQL_LAYER.
storage/myisam/mi_locking.c:
  Call deinitializer for each initialized parser.
storage/myisam/mi_open.c:
  Set default values for share->ftparser and keydef->ftparser_nr.
  If a table is openned from the non-sql layer and HA_OPTION_RELIES_ON_SQL_LAYER is set, raise
  HA_ERR_UNSUPPORTED error.
storage/myisam/myisamdef.h:
  Added number of distinct parsers to MYISAM_SHARE.
  Added ftparser_param to MI_INFO.
plugin/Makefile.am:
  New BitKeeper file ``plugin/Makefile.am''
plugin/fulltext/Makefile.am:
  New BitKeeper file ``plugin/fulltext/Makefile.am''
plugin/fulltext/plugin_example.c:
  New BitKeeper file ``plugin/fulltext/plugin_example.c''

storage/myisam/ft_parser.c

@@ -284,22 +284,110 @@ static int ft_parse_internal(void *param, byte *doc, uint doc_len)
 
 
 int ft_parse(TREE *wtree, byte *doc, int doclen, my_bool with_alloc,
-                    struct st_mysql_ftparser *parser)
+                    struct st_mysql_ftparser *parser,
+                    MYSQL_FTPARSER_PARAM *param)
 {
-  MYSQL_FTPARSER_PARAM param;
   MY_FT_PARSER_PARAM my_param;
   DBUG_ENTER("ft_parse");
   DBUG_ASSERT(parser);
   my_param.wtree= wtree;
   my_param.with_alloc= with_alloc;
 
-  param.mysql_parse= ft_parse_internal;
-  param.mysql_add_word= ft_add_word;
-  param.ftparser_state= 0;
-  param.mysql_ftparam= &my_param;
-  param.cs= wtree->custom_arg;
-  param.doc= doc;
-  param.length= doclen;
-  param.mode= MYSQL_FTPARSER_SIMPLE_MODE;
-  DBUG_RETURN(parser->parse(&param));
+  param->mysql_parse= ft_parse_internal;
+  param->mysql_add_word= ft_add_word;
+  param->mysql_ftparam= &my_param;
+  param->cs= wtree->custom_arg;
+  param->doc= doc;
+  param->length= doclen;
+  param->mode= MYSQL_FTPARSER_SIMPLE_MODE;
+  DBUG_RETURN(parser->parse(param));  
+}
+
+
+MYSQL_FTPARSER_PARAM *ftparser_call_initializer(MI_INFO *info, uint keynr)
+{
+  uint32 ftparser_nr;
+  struct st_mysql_ftparser *parser;
+  if (! info->ftparser_param)
+  {
+    /* info->ftparser_param can not be zero after the initialization,
+       because it always includes built-in fulltext parser. And built-in
+       parser can be called even if the table has no fulltext indexes and
+       no varchar/text fields. */
+    if (! info->s->ftparsers)
+    {
+      /* It's ok that modification to shared structure is done w/o mutex
+         locks, because all threads would set the same variables to the
+         same values. */
+      uint i, j, keys= info->s->state.header.keys, ftparsers= 1;
+      for (i= 0; i < keys; i++)
+      {
+        MI_KEYDEF *keyinfo= &info->s->keyinfo[i];
+        if (keyinfo->flag & HA_FULLTEXT)
+        {
+          for (j= 0;; j++)
+          {
+            if (j == i)
+            {
+              keyinfo->ftparser_nr= ftparsers++;
+              break;
+            }
+            if (info->s->keyinfo[j].flag & HA_FULLTEXT &&
+                keyinfo->parser == info->s->keyinfo[j].parser)
+            {
+              keyinfo->ftparser_nr= info->s->keyinfo[j].ftparser_nr;
+              break;
+            }
+          }
+        }
+      }
+      info->s->ftparsers= ftparsers;
+    }
+    info->ftparser_param= (MYSQL_FTPARSER_PARAM *)
+      my_malloc(sizeof(MYSQL_FTPARSER_PARAM) *
+                info->s->ftparsers, MYF(MY_WME|MY_ZEROFILL));
+    if (! info->ftparser_param)
+      return 0;
+  }
+  if (keynr == NO_SUCH_KEY)
+  {
+    ftparser_nr= 0;
+    parser= &ft_default_parser;
+  }
+  else
+  {
+    ftparser_nr= info->s->keyinfo[keynr].ftparser_nr;
+    parser= info->s->keyinfo[keynr].parser;
+  }
+  if (! info->ftparser_param[ftparser_nr].mysql_add_word)
+  {
+    /* Note, that mysql_add_word is used here as a flag:
+       mysql_add_word == 0 - parser is not initialized
+       mysql_add_word != 0 - parser is initialized, or no
+                             initialization needed. */
+    info->ftparser_param[ftparser_nr].mysql_add_word= (void *)1;
+    if (parser->init && parser->init(&info->ftparser_param[ftparser_nr]))
+      return 0;
+  }
+  return &info->ftparser_param[ftparser_nr];
+}
+
+
+void ftparser_call_deinitializer(MI_INFO *info)
+{
+  uint i, keys= info->s->state.header.keys;
+  if (! info->ftparser_param)
+    return;
+  for (i= 0; i < keys; i++)
+  {
+    MI_KEYDEF *keyinfo= &info->s->keyinfo[i];
+    MYSQL_FTPARSER_PARAM *ftparser_param=
+      &info->ftparser_param[keyinfo->ftparser_nr];
+    if (keyinfo->flag & HA_FULLTEXT && ftparser_param->mysql_add_word)
+    {
+      if (keyinfo->parser->deinit)
+        keyinfo->parser->deinit(ftparser_param);
+      ftparser_param->mysql_add_word= 0;
+    }
+  }
 }