Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

10 files changed, 2385 insertions, 0 deletions

diff --git a/storage/mroonga/udf/Makefile.am b/storage/mroonga/udf/Makefile.am
new file mode 100644
index 00000000..f3c2966f
--- /dev/null
+++ b/storage/mroonga/udf/Makefile.am
@@ -0,0 +1,10 @@
+AM_CPPFLAGS =					\
+	$(MYSQL_INCLUDES)			\
+	$(GROONGA_CFLAGS)			\
+	-I$(top_srcdir)				\
+	-I$(top_srcdir)/lib
+
+noinst_LTLIBRARIES =				\
+	libmrn_udf.la
+
+include sources.am
diff --git a/storage/mroonga/udf/mrn_udf_command.cpp b/storage/mroonga/udf/mrn_udf_command.cpp
new file mode 100644
index 00000000..10123c62
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_command.cpp
@@ -0,0 +1,294 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2010 Tetsuro IKEDA
+  Copyright(C) 2010-2013 Kentoku SHIBA
+  Copyright(C) 2011-2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_path_mapper.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_current_thread.hpp>
+
+#include <sql_table.h>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+struct CommandInfo
+{
+  grn_ctx *ctx;
+  grn_obj *db;
+  bool use_shared_db;
+  grn_obj command;
+  String result;
+};
+
+MRN_API my_bool mroonga_command_init(UDF_INIT *init, UDF_ARGS *args,
+                                     char *message)
+{
+  CommandInfo *info = NULL;
+
+  init->ptr = NULL;
+  if (args->arg_count == 0) {
+    grn_snprintf(message,
+                 MYSQL_ERRMSG_SIZE,
+                 MYSQL_ERRMSG_SIZE,
+                 "mroonga_command(): Wrong number of arguments: %u for 1..",
+                 args->arg_count);
+    goto error;
+  }
+
+  if ((args->arg_count % 2) == 0) {
+    grn_snprintf(message,
+                 MYSQL_ERRMSG_SIZE,
+                 MYSQL_ERRMSG_SIZE,
+                 "mroonga_command(): The number of arguments must be odd: %u",
+                 args->arg_count);
+    goto error;
+  }
+
+  for (unsigned int i = 0; i < args->arg_count; ++i) {
+    switch (args->arg_type[i]) {
+    case STRING_RESULT:
+      // OK
+      break;
+    case REAL_RESULT:
+      grn_snprintf(message,
+                   MYSQL_ERRMSG_SIZE,
+                   MYSQL_ERRMSG_SIZE,
+                   "mroonga_command(): Argument must be string: <%g>",
+                   *reinterpret_cast<double *>(args->args[i]));
+      goto error;
+      break;
+    case INT_RESULT:
+      grn_snprintf(message,
+                   MYSQL_ERRMSG_SIZE,
+                   MYSQL_ERRMSG_SIZE,
+                   "mroonga_command(): Argument must be string: <%lld>",
+                   *reinterpret_cast<longlong *>(args->args[i]));
+      goto error;
+      break;
+    case DECIMAL_RESULT:
+      grn_snprintf(message,
+                   MYSQL_ERRMSG_SIZE,
+                   MYSQL_ERRMSG_SIZE,
+                   "mroonga_command(): Argument must be string: <%.*s>",
+                   static_cast<int>(args->lengths[i]),
+                   args->args[i]);
+      goto error;
+      break;
+    default:
+      grn_snprintf(message,
+                   MYSQL_ERRMSG_SIZE,
+                   MYSQL_ERRMSG_SIZE,
+                   "mroonga_command(): Argument must be string: <%d>(%u)",
+                   args->arg_type[i],
+                   i);
+      goto error;
+      break;
+    }
+  }
+  init->maybe_null = 1;
+  init->const_item = 0;
+
+  info = (CommandInfo *)mrn_my_malloc(sizeof(CommandInfo),
+                                      MYF(MY_WME | MY_ZEROFILL));
+  if (!info) {
+    strcpy(message, "mroonga_command(): out of memory");
+    goto error;
+  }
+
+  info->ctx = mrn_context_pool->pull();
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    const char *action;
+    if (current_db_path) {
+      action = "open database";
+      char encoded_db_path[FN_REFLEN + 1];
+      uint encoded_db_path_length =
+        tablename_to_filename(current_db_path,
+                              encoded_db_path,
+                              sizeof(encoded_db_path));
+      encoded_db_path[encoded_db_path_length] = '\0';
+      mrn::Database *db;
+      int error = mrn_db_manager->open(encoded_db_path, &db);
+      if (error == 0) {
+        info->db = db->get();
+        grn_ctx_use(info->ctx, info->db);
+        info->use_shared_db = true;
+      }
+    } else {
+      action = "create anonymous database";
+      info->db = grn_db_create(info->ctx, NULL, NULL);
+      info->use_shared_db = false;
+    }
+    if (!info->db) {
+      grn_snprintf(message,
+                   MYSQL_ERRMSG_SIZE,
+                   MYSQL_ERRMSG_SIZE,
+                   "mroonga_command(): failed to %s: %s",
+                   action,
+                   info->ctx->errbuf);
+      goto error;
+    }
+  }
+  GRN_TEXT_INIT(&(info->command), 0);
+
+  init->ptr = (char *)info;
+
+  return FALSE;
+
+error:
+  if (info) {
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+  return TRUE;
+}
+
+static void mroonga_command_escape_value(grn_ctx *ctx,
+                                         grn_obj *command,
+                                         const char *value,
+                                         unsigned long value_length)
+{
+  GRN_TEXT_PUTC(ctx, command, '"');
+
+  const char *value_current = value;
+  const char *value_end = value_current + value_length;
+  while (value_current < value_end) {
+    int char_length = grn_charlen(ctx, value_current, value_end);
+
+    if (char_length == 0) {
+      break;
+    } else if (char_length == 1) {
+      switch (*value_current) {
+      case '\\':
+      case '"':
+        GRN_TEXT_PUTC(ctx, command, '\\');
+        GRN_TEXT_PUTC(ctx, command, *value_current);
+        break;
+      case '\n':
+        GRN_TEXT_PUTS(ctx, command, "\\n");
+        break;
+      default:
+        GRN_TEXT_PUTC(ctx, command, *value_current);
+        break;
+      }
+    } else {
+      GRN_TEXT_PUT(ctx, command, value_current, char_length);
+    }
+
+    value_current += char_length;
+  }
+
+  GRN_TEXT_PUTC(ctx, command, '"');
+}
+
+MRN_API char *mroonga_command(UDF_INIT *init, UDF_ARGS *args, char *result,
+                              unsigned long *length, char *is_null, char *error)
+{
+  CommandInfo *info = (CommandInfo *)init->ptr;
+  grn_ctx *ctx = info->ctx;
+  int flags = 0;
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    return NULL;
+  }
+
+  GRN_BULK_REWIND(&(info->command));
+  GRN_TEXT_PUT(ctx, &(info->command), args->args[0], args->lengths[0]);
+  for (unsigned int i = 1; i < args->arg_count; i += 2) {
+    if (!args->args[i] || !args->args[i + 1]) {
+      *is_null = 1;
+      return NULL;
+    }
+
+    const char *name = args->args[i];
+    unsigned long name_length = args->lengths[i];
+    GRN_TEXT_PUTS(ctx, &(info->command), " --");
+    GRN_TEXT_PUT(ctx, &(info->command), name, name_length);
+
+    const char *value = args->args[i + 1];
+    unsigned long value_length = args->lengths[i + 1];
+    GRN_TEXT_PUTS(ctx, &(info->command), " ");
+    mroonga_command_escape_value(ctx, &(info->command), value, value_length);
+  }
+
+  *is_null = 0;
+
+  grn_ctx_send(ctx,
+               GRN_TEXT_VALUE(&(info->command)),
+               GRN_TEXT_LEN(&(info->command)),
+               0);
+  if (ctx->rc) {
+    my_message(ER_ERROR_ON_WRITE, ctx->errbuf, MYF(0));
+    goto error;
+  }
+
+  info->result.length(0);
+  do {
+    char *buffer;
+    unsigned int buffer_length;
+    grn_ctx_recv(ctx, &buffer, &buffer_length, &flags);
+    if (ctx->rc) {
+      my_message(ER_ERROR_ON_READ, ctx->errbuf, MYF(0));
+      goto error;
+    }
+    if (buffer_length > 0) {
+      if (info->result.reserve(buffer_length)) {
+        my_error(ER_OUT_OF_RESOURCES, MYF(0), HA_ERR_OUT_OF_MEM);
+        goto error;
+      }
+      info->result.q_append(buffer, buffer_length);
+    }
+  } while (flags & GRN_CTX_MORE);
+
+  *length = info->result.length();
+  return (char *)(info->result.ptr());
+
+error:
+  *error = 1;
+  return NULL;
+}
+
+MRN_API void mroonga_command_deinit(UDF_INIT *init)
+{
+  CommandInfo *info = (CommandInfo *)init->ptr;
+  if (info) {
+    GRN_OBJ_FIN(info->ctx, &(info->command));
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    MRN_STRING_FREE(info->result);
+    my_free(info);
+  }
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_escape.cpp b/storage/mroonga/udf/mrn_udf_escape.cpp
new file mode 100644
index 00000000..72182790
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_escape.cpp
@@ -0,0 +1,245 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2013-2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_path_mapper.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_context_pool.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::ContextPool *mrn_context_pool;
+
+struct EscapeInfo
+{
+  grn_ctx *ctx;
+  bool script_mode;
+  grn_obj target_characters;
+  grn_obj escaped_value;
+};
+
+MRN_API my_bool mroonga_escape_init(UDF_INIT *init, UDF_ARGS *args,
+                                    char *message)
+{
+  EscapeInfo *info = NULL;
+  bool script_mode = false;
+
+  init->ptr = NULL;
+  if (!(1 <= args->arg_count && args->arg_count <= 2)) {
+    snprintf(message,
+             MYSQL_ERRMSG_SIZE,
+             "mroonga_escape(): Incorrect number of arguments: %u for 1..2",
+             args->arg_count);
+    goto error;
+  }
+
+  if (args->attribute_lengths[0] == strlen("script") &&
+      strncmp(args->attributes[0], "script", strlen("script")) == 0) {
+    switch (args->arg_type[0]) {
+    case ROW_RESULT:
+      snprintf(message,
+               MYSQL_ERRMSG_SIZE,
+               "mroonga_escape(): "
+               "The 1st script argument must be "
+               "string, integer or floating point: <row>");
+      goto error;
+      break;
+    default:
+      break;
+    }
+    script_mode = true;
+  } else {
+    if (args->arg_type[0] != STRING_RESULT) {
+      strcpy(message,
+             "mroonga_escape(): The 1st query argument must be string");
+      goto error;
+    }
+  }
+  if (args->arg_count == 2) {
+    if (args->arg_type[1] != STRING_RESULT) {
+      strcpy(message,
+             "mroonga_escape(): "
+             "The 2st argument must be escape target characters as string");
+      goto error;
+    }
+  }
+
+  init->maybe_null = 1;
+
+  info = static_cast<EscapeInfo *>(mrn_my_malloc(sizeof(EscapeInfo),
+                                                 MYF(MY_WME | MY_ZEROFILL)));
+  if (!info) {
+    strcpy(message, "mroonga_escape(): out of memory");
+    goto error;
+  }
+
+  info->ctx = mrn_context_pool->pull();
+  info->script_mode = script_mode;
+  GRN_TEXT_INIT(&(info->target_characters), 0);
+  GRN_TEXT_INIT(&(info->escaped_value), 0);
+
+  init->ptr = reinterpret_cast<char *>(info);
+
+  return FALSE;
+
+error:
+  if (info) {
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+  return TRUE;
+}
+
+static void escape(EscapeInfo *info, UDF_ARGS *args)
+{
+  grn_ctx *ctx = info->ctx;
+
+  GRN_BULK_REWIND(&(info->escaped_value));
+  if (info->script_mode) {
+    switch (args->arg_type[0]) {
+    case STRING_RESULT:
+      {
+        char *value = args->args[0];
+        unsigned long value_length = args->lengths[0];
+        GRN_TEXT_PUTC(ctx, &(info->escaped_value), '"');
+        if (args->arg_count == 2) {
+          grn_obj special_characters;
+          GRN_TEXT_INIT(&special_characters, 0);
+          GRN_TEXT_PUT(ctx,
+                       &special_characters,
+                       args->args[1],
+                       args->lengths[1]);
+          GRN_TEXT_PUTC(ctx, &special_characters, '\0');
+          grn_expr_syntax_escape(ctx,
+                                 value,
+                                 value_length,
+                                 GRN_TEXT_VALUE(&special_characters),
+                                 '\\',
+                                 &(info->escaped_value));
+          GRN_OBJ_FIN(ctx, &special_characters);
+        } else {
+          const char *special_characters = "\"\\";
+          grn_expr_syntax_escape(ctx,
+                                 value,
+                                 value_length,
+                                 special_characters,
+                                 '\\',
+                                 &(info->escaped_value));
+        }
+        GRN_TEXT_PUTC(ctx, &(info->escaped_value), '"');
+      }
+      break;
+    case REAL_RESULT:
+      {
+        double value = *reinterpret_cast<double *>(args->args[0]);
+        grn_text_ftoa(ctx, &(info->escaped_value), value);
+      }
+      break;
+    case INT_RESULT:
+      {
+        longlong value = *reinterpret_cast<longlong *>(args->args[0]);
+        grn_text_lltoa(ctx, &(info->escaped_value), value);
+      }
+      break;
+    case DECIMAL_RESULT:
+      {
+        grn_obj value_raw;
+        GRN_TEXT_INIT(&value_raw, GRN_OBJ_DO_SHALLOW_COPY);
+        GRN_TEXT_SET(ctx, &value_raw, args->args[0], args->lengths[0]);
+        grn_obj value;
+        GRN_FLOAT_INIT(&value, 0);
+        if (grn_obj_cast(ctx, &value_raw, &value, GRN_FALSE) == GRN_SUCCESS) {
+          grn_text_ftoa(ctx, &(info->escaped_value), GRN_FLOAT_VALUE(&value));
+        } else {
+          GRN_TEXT_PUT(ctx,
+                       &(info->escaped_value),
+                       args->args[0],
+                       args->lengths[0]);
+        }
+        GRN_OBJ_FIN(ctx, &value);
+        GRN_OBJ_FIN(ctx, &value_raw);
+      }
+      break;
+    default:
+      break;
+    }
+  } else {
+    char *query = args->args[0];
+    unsigned long query_length = args->lengths[0];
+    if (args->arg_count == 2) {
+      char *target_characters = args->args[1];
+      unsigned long target_characters_length = args->lengths[1];
+      GRN_TEXT_PUT(ctx, &(info->target_characters),
+                   target_characters,
+                   target_characters_length);
+      GRN_TEXT_PUTC(ctx, &(info->target_characters), '\0');
+      grn_expr_syntax_escape(ctx, query, query_length,
+                             GRN_TEXT_VALUE(&(info->target_characters)),
+                             GRN_QUERY_ESCAPE,
+                             &(info->escaped_value));
+    } else {
+      grn_expr_syntax_escape_query(ctx, query, query_length,
+                                   &(info->escaped_value));
+    }
+  }
+}
+
+MRN_API char *mroonga_escape(UDF_INIT *init, UDF_ARGS *args, char *result,
+                             unsigned long *length, char *is_null, char *error)
+{
+  EscapeInfo *info = reinterpret_cast<EscapeInfo *>(init->ptr);
+  grn_ctx *ctx = info->ctx;
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    return NULL;
+  }
+
+  *is_null = 0;
+
+  escape(info, args);
+
+  if (ctx->rc) {
+    my_message(ER_ERROR_ON_WRITE, ctx->errbuf, MYF(0));
+    goto error;
+  }
+
+  *length = GRN_TEXT_LEN(&(info->escaped_value));
+  return GRN_TEXT_VALUE(&(info->escaped_value));
+
+error:
+  *error = 1;
+  return NULL;
+}
+
+MRN_API void mroonga_escape_deinit(UDF_INIT *init)
+{
+  EscapeInfo *info = reinterpret_cast<EscapeInfo *>(init->ptr);
+  if (info) {
+    grn_obj_unlink(info->ctx, &(info->target_characters));
+    grn_obj_unlink(info->ctx, &(info->escaped_value));
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_highlight_html.cpp b/storage/mroonga/udf/mrn_udf_highlight_html.cpp
new file mode 100644
index 00000000..12f54a7d
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_highlight_html.cpp
@@ -0,0 +1,494 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_err.h>
+#include <mrn_encoding.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_table.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_query_parser.hpp>
+#include <mrn_current_thread.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+typedef struct st_mrn_highlight_html_info
+{
+  grn_ctx *ctx;
+  grn_obj *db;
+  bool use_shared_db;
+  grn_obj *keywords;
+  String result_str;
+  struct {
+    bool used;
+    grn_obj *table;
+    grn_obj *default_column;
+  } query_mode;
+} mrn_highlight_html_info;
+
+static my_bool mrn_highlight_html_prepare(mrn_highlight_html_info *info,
+                                          UDF_ARGS *args,
+                                          char *message,
+                                          grn_obj **keywords)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  grn_ctx *ctx = info->ctx;
+  const char *normalizer_name = "NormalizerAuto";
+  grn_obj *expr = NULL;
+  String *result_str = &(info->result_str);
+
+  *keywords = NULL;
+
+  mrn::encoding::set_raw(ctx, system_charset_info);
+  if (system_charset_info->state & (MY_CS_BINSORT | MY_CS_CSSORT)) {
+    normalizer_name = NULL;
+  }
+
+  *keywords = grn_table_create(ctx, NULL, 0, NULL,
+                               GRN_OBJ_TABLE_PAT_KEY,
+                               grn_ctx_at(ctx, GRN_DB_SHORT_TEXT),
+                               NULL);
+  if (ctx->rc != GRN_SUCCESS) {
+    if (message) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_highlight_html(): "
+               "failed to create grn_pat for keywords: <%s>",
+               ctx->errbuf);
+    }
+    goto error;
+  }
+  if (normalizer_name) {
+    grn_obj_set_info(ctx,
+                     *keywords,
+                     GRN_INFO_NORMALIZER,
+                     grn_ctx_get(ctx, normalizer_name, -1));
+  }
+
+  if (info->query_mode.used) {
+    if (!info->query_mode.table) {
+      grn_obj *short_text;
+      short_text = grn_ctx_at(info->ctx, GRN_DB_SHORT_TEXT);
+      info->query_mode.table = grn_table_create(info->ctx,
+                                                NULL, 0, NULL,
+                                                GRN_TABLE_HASH_KEY,
+                                                short_text,
+                                                NULL);
+    }
+    if (!info->query_mode.default_column) {
+      info->query_mode.default_column =
+        grn_obj_column(info->ctx,
+                       info->query_mode.table,
+                       GRN_COLUMN_NAME_KEY,
+                       GRN_COLUMN_NAME_KEY_LEN);
+    }
+
+    grn_obj *record = NULL;
+    GRN_EXPR_CREATE_FOR_QUERY(info->ctx, info->query_mode.table, expr, record);
+    if (!expr) {
+      if (message) {
+        snprintf(message, MYSQL_ERRMSG_SIZE,
+                 "mroonga_highlight_html(): "
+                 "failed to create expression: <%s>",
+                 ctx->errbuf);
+      }
+      goto error;
+    }
+
+    mrn::QueryParser query_parser(info->ctx,
+                                  current_thd,
+                                  expr,
+                                  info->query_mode.default_column,
+                                  0,
+                                  NULL);
+    grn_rc rc = query_parser.parse(args->args[1], args->lengths[1]);
+    if (rc != GRN_SUCCESS) {
+      if (message) {
+        snprintf(message, MYSQL_ERRMSG_SIZE,
+                 "mroonga_highlight_html(): "
+                 "failed to parse query: <%s>",
+                 ctx->errbuf);
+      }
+      goto error;
+    }
+
+    {
+      grn_obj extracted_keywords;
+      GRN_PTR_INIT(&extracted_keywords, GRN_OBJ_VECTOR, GRN_ID_NIL);
+      grn_expr_get_keywords(ctx, expr, &extracted_keywords);
+
+      size_t n_keywords =
+        GRN_BULK_VSIZE(&extracted_keywords) / sizeof(grn_obj *);
+      for (size_t i = 0; i < n_keywords; ++i) {
+        grn_obj *extracted_keyword = GRN_PTR_VALUE_AT(&extracted_keywords, i);
+        grn_table_add(ctx,
+                      *keywords,
+                      GRN_TEXT_VALUE(extracted_keyword),
+                      GRN_TEXT_LEN(extracted_keyword),
+                      NULL);
+        if (ctx->rc != GRN_SUCCESS) {
+          if (message) {
+            snprintf(message, MYSQL_ERRMSG_SIZE,
+                     "mroonga_highlight_html(): "
+                     "failed to add a keyword: <%.*s>: <%s>",
+                     static_cast<int>(GRN_TEXT_LEN(extracted_keyword)),
+                     GRN_TEXT_VALUE(extracted_keyword),
+                     ctx->errbuf);
+            GRN_OBJ_FIN(ctx, &extracted_keywords);
+          }
+          goto error;
+        }
+      }
+      GRN_OBJ_FIN(ctx, &extracted_keywords);
+    }
+  } else {
+    for (unsigned int i = 1; i < args->arg_count; ++i) {
+      if (!args->args[i]) {
+        continue;
+      }
+      grn_table_add(ctx,
+                    *keywords,
+                    args->args[i],
+                    args->lengths[i],
+                    NULL);
+      if (ctx->rc != GRN_SUCCESS) {
+        if (message) {
+          snprintf(message, MYSQL_ERRMSG_SIZE,
+                   "mroonga_highlight_html(): "
+                   "failed to add a keyword: <%.*s>: <%s>",
+                   static_cast<int>(args->lengths[i]),
+                   args->args[i],
+                   ctx->errbuf);
+        }
+        goto error;
+      }
+    }
+  }
+
+  result_str->set_charset(system_charset_info);
+  DBUG_RETURN(FALSE);
+
+error:
+  if (expr) {
+    grn_obj_close(ctx, expr);
+  }
+  if (*keywords) {
+    grn_obj_close(ctx, *keywords);
+  }
+  DBUG_RETURN(TRUE);
+}
+
+MRN_API my_bool mroonga_highlight_html_init(UDF_INIT *init,
+                                            UDF_ARGS *args,
+                                            char *message)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_highlight_html_info *info = NULL;
+
+  init->ptr = NULL;
+
+  if (args->arg_count < 1) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_highlight_html(): wrong number of arguments: %u for 1+",
+             args->arg_count);
+    goto error;
+  }
+
+
+  for (unsigned int i = 0; i < args->arg_count; ++i) {
+    switch (args->arg_type[i]) {
+    case STRING_RESULT:
+      /* OK */
+      break;
+    case REAL_RESULT:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_highlight_html(): all arguments must be string: "
+               "<%u>=<%g>",
+               i, *((double *)(args->args[i])));
+      goto error;
+      break;
+    case INT_RESULT:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_highlight_html(): all arguments must be string: "
+               "<%u>=<%lld>",
+               i, *((longlong *)(args->args[i])));
+      goto error;
+      break;
+    default:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_highlight_html(): all arguments must be string: <%u>",
+               i);
+      goto error;
+      break;
+    }
+  }
+
+  init->maybe_null = 0;
+
+  info =
+    reinterpret_cast<mrn_highlight_html_info *>(
+      mrn_my_malloc(sizeof(mrn_highlight_html_info),
+                    MYF(MY_WME | MY_ZEROFILL)));
+  if (!info) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_highlight_html(): failed to allocate memory");
+    goto error;
+  }
+
+  info->ctx = mrn_context_pool->pull();
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    const char *action;
+    if (current_db_path) {
+      action = "open database";
+      mrn::Database *db;
+      int error = mrn_db_manager->open(current_db_path, &db);
+      if (error == 0) {
+        info->db = db->get();
+        grn_ctx_use(info->ctx, info->db);
+        info->use_shared_db = true;
+      }
+    } else {
+      action = "create anonymous database";
+      info->db = grn_db_create(info->ctx, NULL, NULL);
+      info->use_shared_db = false;
+    }
+    if (!info->db) {
+      sprintf(message,
+              "mroonga_highlight_html(): failed to %s: %s",
+              action,
+              info->ctx->errbuf);
+      goto error;
+    }
+  }
+
+  info->query_mode.used = FALSE;
+
+  if (args->arg_count == 2 &&
+      args->attribute_lengths[1] == strlen("query") &&
+      strncmp(args->attributes[1], "query", strlen("query")) == 0) {
+    info->query_mode.used = TRUE;
+    info->query_mode.table = NULL;
+    info->query_mode.default_column = NULL;
+  }
+
+  {
+    bool all_keywords_are_constant = TRUE;
+    for (unsigned int i = 1; i < args->arg_count; ++i) {
+      if (!args->args[i]) {
+        all_keywords_are_constant = FALSE;
+        break;
+      }
+    }
+
+    if (all_keywords_are_constant) {
+      if (mrn_highlight_html_prepare(info, args, message, &(info->keywords))) {
+        goto error;
+      }
+    } else {
+      info->keywords = NULL;
+    }
+  }
+
+  init->ptr = (char *)info;
+
+  DBUG_RETURN(FALSE);
+
+error:
+  if (info) {
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+  DBUG_RETURN(TRUE);
+}
+
+static bool highlight_html(grn_ctx *ctx,
+                           grn_pat *keywords,
+                           const char *target,
+                           size_t target_length,
+                           String *output)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  grn_obj buffer;
+
+  GRN_TEXT_INIT(&buffer, 0);
+
+  {
+    const char *open_tag = "<span class=\"keyword\">";
+    size_t open_tag_length = strlen(open_tag);
+    const char *close_tag = "</span>";
+    size_t close_tag_length = strlen(close_tag);
+
+    while (target_length > 0) {
+#define MAX_N_HITS 16
+      grn_pat_scan_hit hits[MAX_N_HITS];
+      const char *rest;
+      size_t previous = 0;
+      size_t chunk_length;
+
+      int n_hits = grn_pat_scan(ctx,
+                                keywords,
+                                target,
+                                target_length,
+                                hits, MAX_N_HITS, &rest);
+      for (int i = 0; i < n_hits; i++) {
+        if ((hits[i].offset - previous) > 0) {
+          grn_text_escape_xml(ctx,
+                              &buffer,
+                              target + previous,
+                              hits[i].offset - previous);
+        }
+        GRN_TEXT_PUT(ctx, &buffer, open_tag, open_tag_length);
+        grn_text_escape_xml(ctx,
+                            &buffer,
+                            target + hits[i].offset,
+                            hits[i].length);
+        GRN_TEXT_PUT(ctx, &buffer, close_tag, close_tag_length);
+        previous = hits[i].offset + hits[i].length;
+      }
+
+      chunk_length = rest - target;
+      if ((chunk_length - previous) > 0) {
+        grn_text_escape_xml(ctx,
+                            &buffer,
+                            target + previous,
+                            target_length - previous);
+      }
+      target_length -= chunk_length;
+      target = rest;
+#undef MAX_N_HITS
+    }
+  }
+
+  if (output->reserve(GRN_TEXT_LEN(&buffer))) {
+    my_error(ER_OUT_OF_RESOURCES, MYF(0), HA_ERR_OUT_OF_MEM);
+    GRN_OBJ_FIN(ctx, &buffer);
+    DBUG_RETURN(false);
+  }
+
+  output->q_append(GRN_TEXT_VALUE(&buffer), GRN_TEXT_LEN(&buffer));
+  GRN_OBJ_FIN(ctx, &buffer);
+  DBUG_RETURN(true);
+}
+
+MRN_API char *mroonga_highlight_html(UDF_INIT *init,
+                                     UDF_ARGS *args,
+                                     char *result,
+                                     unsigned long *length,
+                                     char *is_null,
+                                     char *error)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_highlight_html_info *info =
+    reinterpret_cast<mrn_highlight_html_info *>(init->ptr);
+
+  grn_ctx *ctx = info->ctx;
+  grn_obj *keywords = info->keywords;
+  String *result_str = &(info->result_str);
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    DBUG_RETURN(NULL);
+  }
+
+  if (!keywords) {
+    if (mrn_highlight_html_prepare(info, args, NULL, &keywords)) {
+      goto error;
+    }
+  }
+
+  *is_null = 0;
+  result_str->length(0);
+
+  if (!highlight_html(ctx,
+                      reinterpret_cast<grn_pat *>(keywords),
+                      args->args[0],
+                      args->lengths[0],
+                      result_str)) {
+    goto error;
+  }
+
+  if (!info->keywords) {
+    grn_rc rc = grn_obj_close(ctx, keywords);
+    if (rc != GRN_SUCCESS) {
+      my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                      ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+        goto error;
+    }
+  }
+
+  *length = result_str->length();
+  DBUG_RETURN((char *)result_str->ptr());
+
+error:
+  if (!info->keywords && keywords) {
+    grn_obj_close(ctx, keywords);
+  }
+
+  *is_null = 1;
+  *error = 1;
+
+  DBUG_RETURN(NULL);
+}
+
+MRN_API void mroonga_highlight_html_deinit(UDF_INIT *init)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_highlight_html_info *info =
+    reinterpret_cast<mrn_highlight_html_info *>(init->ptr);
+  if (!info) {
+    DBUG_VOID_RETURN;
+  }
+
+  if (info->keywords) {
+    grn_obj_close(info->ctx, info->keywords);
+  }
+  if (info->query_mode.used) {
+    if (info->query_mode.default_column) {
+      grn_obj_close(info->ctx, info->query_mode.default_column);
+    }
+    if (info->query_mode.table) {
+      grn_obj_close(info->ctx, info->query_mode.table);
+    }
+  }
+  MRN_STRING_FREE(info->result_str);
+  if (!info->use_shared_db) {
+    grn_obj_close(info->ctx, info->db);
+  }
+  mrn_context_pool->release(info->ctx);
+  my_free(info);
+
+  DBUG_VOID_RETURN;
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_last_insert_grn_id.cpp b/storage/mroonga/udf/mrn_udf_last_insert_grn_id.cpp
new file mode 100644
index 00000000..46176bc8
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_last_insert_grn_id.cpp
@@ -0,0 +1,55 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2010 Tetsuro IKEDA
+  Copyright(C) 2010-2013 Kentoku SHIBA
+  Copyright(C) 2011-2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_windows.hpp>
+#include <mrn_table.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_current_thread.hpp>
+
+MRN_BEGIN_DECLS
+
+MRN_API my_bool last_insert_grn_id_init(UDF_INIT *init, UDF_ARGS *args, char *message)
+{
+  if (args->arg_count != 0) {
+    strcpy(message, "last_insert_grn_id must not have arguments");
+    return 1;
+  }
+  init->maybe_null = 0;
+  return 0;
+}
+
+MRN_API longlong last_insert_grn_id(UDF_INIT *init, UDF_ARGS *args, char *is_null, char *error)
+{
+  THD *thd = current_thd;
+  st_mrn_slot_data *slot_data = mrn_get_slot_data(thd, false);
+  if (slot_data == NULL) {
+    return 0;
+  }
+  longlong last_insert_record_id = slot_data->last_insert_record_id;
+  return last_insert_record_id;
+}
+
+MRN_API void last_insert_grn_id_deinit(UDF_INIT *init)
+{
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_normalize.cpp b/storage/mroonga/udf/mrn_udf_normalize.cpp
new file mode 100644
index 00000000..30362351
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_normalize.cpp
@@ -0,0 +1,212 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2015 Naoya Murakami <naoya@createfield.com>
+  Copyright(C) 2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_encoding.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_table.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_current_thread.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+#define DEFAULT_NORMALIZER_NAME "NormalizerAuto"
+
+struct st_mrn_normalize_info
+{
+  grn_ctx *ctx;
+  grn_obj *db;
+  bool use_shared_db;
+  grn_obj *normalizer;
+  int flags;
+  String result_str;
+};
+
+MRN_API my_bool mroonga_normalize_init(UDF_INIT *init, UDF_ARGS *args,
+                                       char *message)
+{
+  st_mrn_normalize_info *info = NULL;
+  String *result_str = NULL;
+
+  init->ptr = NULL;
+  if (!(1 <= args->arg_count && args->arg_count <= 2)) {
+    sprintf(message,
+            "mroonga_normalize(): Incorrect number of arguments: %u for 1..2",
+            args->arg_count);
+    goto error;
+  }
+  if (args->arg_type[0] != STRING_RESULT) {
+    strcpy(message,
+           "mroonga_normalize(): The 1st argument must be query as string");
+    goto error;
+  }
+  if (args->arg_count == 2) {
+    if (args->arg_type[1] != STRING_RESULT) {
+      strcpy(message,
+             "mroonga_normalize(): "
+             "The 2st argument must be normalizer name as string");
+      goto error;
+    }
+  }
+
+  init->maybe_null = 1;
+
+  info = (st_mrn_normalize_info *)mrn_my_malloc(sizeof(st_mrn_normalize_info),
+                                                MYF(MY_WME | MY_ZEROFILL));
+  if (!info) {
+    strcpy(message, "mroonga_normalize(): out of memory");
+    goto error;
+  }
+
+  info->ctx = mrn_context_pool->pull();
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    const char *action;
+    if (current_db_path) {
+      action = "open database";
+      mrn::Database *db;
+      int error = mrn_db_manager->open(current_db_path, &db);
+      if (error == 0) {
+        info->db = db->get();
+        grn_ctx_use(info->ctx, info->db);
+        info->use_shared_db = true;
+      }
+    } else {
+      action = "create anonymous database";
+      info->db = grn_db_create(info->ctx, NULL, NULL);
+      info->use_shared_db = false;
+    }
+    if (!info->db) {
+      sprintf(message,
+              "mroonga_normalize(): failed to %s: %s",
+              action,
+              info->ctx->errbuf);
+      goto error;
+    }
+  }
+
+  if (args->arg_count == 1) {
+    info->normalizer = grn_ctx_get(info->ctx, DEFAULT_NORMALIZER_NAME, -1);
+  } else {
+    info->normalizer = grn_ctx_get(info->ctx, args->args[1], args->lengths[1]);
+  }
+  if (!info->normalizer) {
+    sprintf(message, "mroonga_normalize(): nonexistent normalizer %.*s",
+            (int)args->lengths[1], args->args[1]);
+    goto error;
+  }
+  info->flags = 0;
+
+  result_str = &(info->result_str);
+  mrn::encoding::set_raw(info->ctx, system_charset_info);
+  result_str->set_charset(system_charset_info);
+
+  init->ptr = (char *)info;
+
+  return FALSE;
+
+error:
+  if (info) {
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+  return TRUE;
+}
+
+MRN_API char *mroonga_normalize(UDF_INIT *init, UDF_ARGS *args, char *result,
+                                unsigned long *length, char *is_null, char *error)
+{
+  st_mrn_normalize_info *info = (st_mrn_normalize_info *)init->ptr;
+  grn_ctx *ctx = info->ctx;
+  String *result_str = &(info->result_str);
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    return NULL;
+  }
+
+  result_str->length(0);
+  {
+    char *target = args->args[0];
+    unsigned int target_length = args->lengths[0];
+    grn_obj *grn_string;
+    const char *normalized;
+    unsigned int normalized_length_in_bytes;
+    unsigned int normalized_n_characters;
+
+    grn_string = grn_string_open(ctx,
+                                 target, target_length,
+                                 info->normalizer, info->flags);
+    grn_string_get_normalized(ctx, grn_string,
+                              &normalized,
+                              &normalized_length_in_bytes,
+                              &normalized_n_characters);
+    if (result_str->reserve(normalized_length_in_bytes)) {
+      my_error(ER_OUT_OF_RESOURCES, MYF(0), HA_ERR_OUT_OF_MEM);
+      goto error;
+    }
+    result_str->q_append(normalized, normalized_length_in_bytes);
+    result_str->length(normalized_length_in_bytes);
+    grn_obj_unlink(ctx, grn_string);
+  }
+  *is_null = 0;
+
+  if (ctx->rc) {
+    my_message(ER_ERROR_ON_WRITE, ctx->errbuf, MYF(0));
+    goto error;
+  }
+
+  *length = result_str->length();
+  return (char *)result_str->ptr();
+
+error:
+  *is_null = 1;
+  *error = 1;
+  return NULL;
+}
+
+MRN_API void mroonga_normalize_deinit(UDF_INIT *init)
+{
+  st_mrn_normalize_info *info = (st_mrn_normalize_info *)init->ptr;
+
+  if (info) {
+    MRN_STRING_FREE(info->result_str);
+    if (info->normalizer) {
+      grn_obj_unlink(info->ctx, info->normalizer);
+    }
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_query_expand.cpp b/storage/mroonga/udf/mrn_udf_query_expand.cpp
new file mode 100644
index 00000000..03bef321
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_query_expand.cpp
@@ -0,0 +1,282 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_path_mapper.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_current_thread.hpp>
+#include <mrn_query_parser.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+namespace mrn {
+  struct QueryExpandInfo {
+    grn_ctx *ctx;
+    grn_obj expanded_query;
+    grn_obj *term_column;
+    grn_obj *expanded_term_column;
+  };
+}
+
+static void mrn_query_expand_info_free(mrn::QueryExpandInfo *info)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  if (!info) {
+    DBUG_VOID_RETURN;
+  }
+
+  if (info->ctx) {
+    GRN_OBJ_FIN(info->ctx, &(info->expanded_query));
+    if (grn_obj_is_accessor(info->ctx, info->expanded_term_column)) {
+      grn_obj_unlink(info->ctx, info->expanded_term_column);
+    }
+    if (grn_obj_is_accessor(info->ctx, info->term_column)) {
+      grn_obj_unlink(info->ctx, info->term_column);
+    }
+    mrn_context_pool->release(info->ctx);
+  }
+  my_free(info);
+
+  DBUG_VOID_RETURN;
+}
+
+MRN_API my_bool mroonga_query_expand_init(UDF_INIT *init,
+                                          UDF_ARGS *args,
+                                          char *message)
+{
+  mrn::QueryExpandInfo *info = NULL;
+
+  MRN_DBUG_ENTER_FUNCTION();
+
+  init->ptr = NULL;
+  if (args->arg_count != 4) {
+    sprintf(message,
+            "mroonga_query_expand(): wrong number of arguments: %u for 4",
+            args->arg_count);
+    goto error;
+  }
+  if (args->arg_type[0] != STRING_RESULT) {
+    strcpy(message,
+           "mroonga_query_expand(): "
+           "the 1st argument must be table name as string");
+    goto error;
+  }
+  if (args->arg_type[1] != STRING_RESULT) {
+    strcpy(message,
+           "mroonga_query_expand(): "
+           "the 2nd argument must be term column name as string");
+    goto error;
+  }
+  if (args->arg_type[2] != STRING_RESULT) {
+    strcpy(message,
+           "mroonga_query_expand(): "
+           "the 3nd argument must be expanded term column name as string");
+    goto error;
+  }
+  if (args->arg_type[3] != STRING_RESULT) {
+    strcpy(message,
+           "mroonga_query_expand(): "
+           "the 4th argument must be query as string");
+    goto error;
+  }
+
+  init->maybe_null = 1;
+
+  info = static_cast<mrn::QueryExpandInfo *>(
+    mrn_my_malloc(sizeof(mrn::QueryExpandInfo),
+                  MYF(MY_WME | MY_ZEROFILL)));
+  if (!info) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_query_expand(): failed to allocate memory");
+    goto error;
+  }
+
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    if (!current_db_path) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_query_expand(): no current database");
+      goto error;
+    }
+
+    mrn::Database *db;
+    int error = mrn_db_manager->open(current_db_path, &db);
+    if (error != 0) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_query_expand(): failed to open database: %s",
+               mrn_db_manager->error_message());
+      goto error;
+    }
+    info->ctx = mrn_context_pool->pull();
+    grn_ctx_use(info->ctx, db->get());
+  }
+
+  GRN_TEXT_INIT(&(info->expanded_query), 0);
+
+  {
+    const char *table_name = args->args[0];
+    unsigned int table_name_length = args->lengths[0];
+    grn_obj *table = grn_ctx_get(info->ctx,
+                                 table_name,
+                                 table_name_length);
+    if (!table) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_query_expand(): table doesn't exist: <%.*s>",
+               static_cast<int>(table_name_length),
+               table_name);
+      goto error;
+    }
+
+    const char *term_column_name = args->args[1];
+    unsigned int term_column_name_length = args->lengths[1];
+    info->term_column = grn_obj_column(info->ctx,
+                                       table,
+                                       term_column_name,
+                                       term_column_name_length);
+    if (!info->term_column) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_query_expand(): term column doesn't exist: <%.*s.%.*s>",
+               static_cast<int>(table_name_length),
+               table_name,
+               static_cast<int>(term_column_name_length),
+               term_column_name);
+      goto error;
+    }
+
+    const char *expanded_term_column_name = args->args[2];
+    unsigned int expanded_term_column_name_length = args->lengths[2];
+    info->expanded_term_column = grn_obj_column(info->ctx,
+                                                table,
+                                                expanded_term_column_name,
+                                                expanded_term_column_name_length);
+    if (!info->expanded_term_column) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_query_expand(): "
+               "expanded term column doesn't exist: <%.*s.%.*s>",
+               static_cast<int>(table_name_length),
+               table_name,
+               static_cast<int>(expanded_term_column_name_length),
+               expanded_term_column_name);
+      goto error;
+    }
+  }
+
+  init->ptr = reinterpret_cast<char *>(info);
+
+  DBUG_RETURN(FALSE);
+
+error:
+  mrn_query_expand_info_free(info);
+  DBUG_RETURN(TRUE);
+}
+
+static void query_expand(mrn::QueryExpandInfo *info, UDF_ARGS *args)
+{
+  grn_ctx *ctx = info->ctx;
+  const char *query = args->args[3];
+  unsigned int query_length = args->lengths[3];
+
+  mrn::QueryParser query_parser(info->ctx,
+                                current_thd,
+                                NULL,
+                                NULL,
+                                0,
+                                NULL);
+  const char *raw_query;
+  size_t raw_query_length;
+  grn_operator default_operator;
+  grn_expr_flags flags;
+  query_parser.parse_pragma(query,
+                            query_length,
+                            &raw_query,
+                            &raw_query_length,
+                            &default_operator,
+                            &flags);
+  GRN_TEXT_SET(info->ctx,
+               &(info->expanded_query),
+               query,
+               raw_query - query);
+  grn_expr_syntax_expand_query_by_table(ctx,
+                                        raw_query,
+                                        raw_query_length,
+                                        flags,
+                                        info->term_column,
+                                        info->expanded_term_column,
+                                        &(info->expanded_query));
+}
+
+MRN_API char *mroonga_query_expand(UDF_INIT *init,
+                                   UDF_ARGS *args,
+                                   char *result,
+                                   unsigned long *length,
+                                   char *is_null,
+                                   char *error)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn::QueryExpandInfo *info =
+    reinterpret_cast<mrn::QueryExpandInfo *>(init->ptr);
+  grn_ctx *ctx = info->ctx;
+
+  if (!args->args[3]) {
+    *is_null = 1;
+    DBUG_RETURN(NULL);
+  }
+
+  *is_null = 0;
+
+  query_expand(info, args);
+
+  if (ctx->rc) {
+    char message[MYSQL_ERRMSG_SIZE];
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_query_expand(): "
+             "failed to expand: %s",
+             ctx->errbuf);
+    my_message(ER_ERROR_ON_WRITE, message, MYF(0));
+    goto error;
+  }
+
+  *length = GRN_TEXT_LEN(&(info->expanded_query));
+  DBUG_RETURN(GRN_TEXT_VALUE(&(info->expanded_query)));
+
+error:
+  *error = 1;
+  DBUG_RETURN(NULL);
+}
+
+MRN_API void mroonga_query_expand_deinit(UDF_INIT *init)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+  mrn::QueryExpandInfo *info =
+    reinterpret_cast<mrn::QueryExpandInfo *>(init->ptr);
+  mrn_query_expand_info_free(info);
+  DBUG_VOID_RETURN;
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_snippet.cpp b/storage/mroonga/udf/mrn_udf_snippet.cpp
new file mode 100644
index 00000000..90d3721e
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_snippet.cpp
@@ -0,0 +1,340 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2010 Tetsuro IKEDA
+  Copyright(C) 2010-2013 Kentoku SHIBA
+  Copyright(C) 2011-2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_err.h>
+#include <mrn_encoding.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_table.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_current_thread.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+struct st_mrn_snip_info
+{
+  grn_ctx *ctx;
+  grn_obj *db;
+  bool use_shared_db;
+  grn_obj *snippet;
+  String result_str;
+};
+
+static my_bool mrn_snippet_prepare(st_mrn_snip_info *snip_info, UDF_ARGS *args,
+                                   char *message, grn_obj **snippet)
+{
+  unsigned int i;
+  CHARSET_INFO *cs;
+  grn_ctx *ctx = snip_info->ctx;
+  long long snip_max_len;
+  long long snip_max_num;
+  long long skip_leading_spaces;
+  long long html_escape;
+  int flags = GRN_SNIP_COPY_TAG;
+  grn_snip_mapping *mapping = NULL;
+  grn_rc rc;
+  String *result_str = &snip_info->result_str;
+  myf utf8_flag= current_thd->get_utf8_flag();
+
+  *snippet = NULL;
+  snip_max_len = *((long long *) args->args[1]);
+  snip_max_num = *((long long *) args->args[2]);
+
+  if (args->arg_type[3] == STRING_RESULT) {
+    if (!(cs = get_charset_by_name(args->args[3],
+                                   MYF(utf8_flag)))) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "Unknown charset: <%s>", args->args[3]);
+      goto error;
+    }
+  } else {
+    uint charset_id = static_cast<uint>(*((long long *) args->args[3]));
+    if (!(cs = get_charset(charset_id, MYF(0)))) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "Unknown charset ID: <%u>", charset_id);
+      goto error;
+    }
+  }
+  if (!mrn::encoding::set_raw(ctx, cs)) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "Unsupported charset: <%s>", cs->coll_name.str);
+    goto error;
+  }
+
+  if (!(cs->state & (MY_CS_BINSORT | MY_CS_CSSORT))) {
+    flags |= GRN_SNIP_NORMALIZE;
+  }
+
+  skip_leading_spaces = *((long long *) args->args[4]);
+  if (skip_leading_spaces) {
+    flags |= GRN_SNIP_SKIP_LEADING_SPACES;
+  }
+
+  html_escape = *((long long *) args->args[5]);
+  if (html_escape) {
+    mapping = (grn_snip_mapping *) -1;
+  }
+
+  *snippet = grn_snip_open(ctx, flags, static_cast<unsigned int>(snip_max_len),
+                           static_cast<unsigned int>(snip_max_num),
+                           "", 0, "", 0, mapping);
+  if (ctx->rc) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "Failed to open grn_snip: <%s>", ctx->errbuf);
+    goto error;
+  }
+
+  for (i = 8; i < args->arg_count; i += 3) {
+    rc = grn_snip_add_cond(ctx, *snippet,
+                           args->args[i], args->lengths[i],
+                           args->args[i + 1], args->lengths[i + 1],
+                           args->args[i + 2], args->lengths[i + 2]);
+    if (rc) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "Failed to add a condition to grn_snip: <%s>", ctx->errbuf);
+      goto error;
+    }
+  }
+
+  result_str->set_charset(cs);
+  return FALSE;
+
+error:
+  if (*snippet) {
+    grn_obj_close(ctx, *snippet);
+  }
+  return TRUE;
+}
+
+MRN_API my_bool mroonga_snippet_init(UDF_INIT *init, UDF_ARGS *args, char *message)
+{
+  uint i;
+  st_mrn_snip_info *snip_info = NULL;
+  bool can_open_snippet = TRUE;
+  init->ptr = NULL;
+  if (args->arg_count < 11 || (args->arg_count - 11) % 3)
+  {
+    sprintf(message, "Incorrect number of arguments for mroonga_snippet(): %u",
+            args->arg_count);
+    goto error;
+  }
+  if (args->arg_type[0] != STRING_RESULT) {
+    strcpy(message, "mroonga_snippet() requires string for 1st argument");
+    goto error;
+  }
+  if (args->arg_type[1] != INT_RESULT) {
+    strcpy(message, "mroonga_snippet() requires int for 2nd argument");
+    goto error;
+  }
+  if (args->arg_type[2] != INT_RESULT) {
+    strcpy(message, "mroonga_snippet() requires int for 3rd argument");
+    goto error;
+  }
+  if (
+    args->arg_type[3] != STRING_RESULT &&
+    args->arg_type[3] != INT_RESULT
+  ) {
+    strcpy(message,
+      "mroonga_snippet() requires string or int for 4th argument");
+    goto error;
+  }
+  if (args->arg_type[4] != INT_RESULT) {
+    strcpy(message, "mroonga_snippet() requires int for 5th argument");
+    goto error;
+  }
+  if (args->arg_type[5] != INT_RESULT) {
+    strcpy(message, "mroonga_snippet() requires int for 6th argument");
+    goto error;
+  }
+  for (i = 6; i < args->arg_count; i++) {
+    if (args->arg_type[i] != STRING_RESULT) {
+      sprintf(message, "mroonga_snippet() requires string for %uth argument",
+              i);
+      goto error;
+    }
+  }
+  init->maybe_null = 1;
+
+  if (!(snip_info = (st_mrn_snip_info *) mrn_my_malloc(sizeof(st_mrn_snip_info),
+                                                       MYF(MY_WME | MY_ZEROFILL))))
+  {
+    strcpy(message, "mroonga_snippet() out of memory");
+    goto error;
+  }
+  snip_info->ctx = mrn_context_pool->pull();
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    const char *action;
+    if (current_db_path) {
+      action = "open database";
+      mrn::Database *db;
+      int error = mrn_db_manager->open(current_db_path, &db);
+      if (error == 0) {
+        snip_info->db = db->get();
+        grn_ctx_use(snip_info->ctx, snip_info->db);
+        snip_info->use_shared_db = true;
+      }
+    } else {
+      action = "create anonymous database";
+      snip_info->db = grn_db_create(snip_info->ctx, NULL, NULL);
+      snip_info->use_shared_db = false;
+    }
+    if (!snip_info->db) {
+      sprintf(message,
+              "mroonga_snippet(): failed to %s: %s",
+              action,
+              snip_info->ctx->errbuf);
+      goto error;
+    }
+  }
+
+  for (i = 1; i < args->arg_count; i++) {
+    if (!args->args[i]) {
+      can_open_snippet = FALSE;
+      break;
+    }
+  }
+  if (can_open_snippet) {
+    if (mrn_snippet_prepare(snip_info, args, message, &snip_info->snippet)) {
+      goto error;
+    }
+  }
+  init->ptr = (char *) snip_info;
+
+  return FALSE;
+
+error:
+  if (snip_info) {
+    if (!snip_info->use_shared_db) {
+      grn_obj_close(snip_info->ctx, snip_info->db);
+    }
+    mrn_context_pool->release(snip_info->ctx);
+    my_free(snip_info);
+  }
+  return TRUE;
+}
+
+MRN_API char *mroonga_snippet(UDF_INIT *init, UDF_ARGS *args, char *result,
+                              unsigned long *length, char *is_null, char *error)
+{
+  st_mrn_snip_info *snip_info = (st_mrn_snip_info *) init->ptr;
+  grn_ctx *ctx = snip_info->ctx;
+  String *result_str = &snip_info->result_str;
+  char *target;
+  unsigned int target_length;
+  grn_obj *snippet = NULL;
+  grn_rc rc;
+  unsigned int i, n_results, max_tagged_length, result_length;
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    return NULL;
+  }
+  *is_null = 0;
+  target = args->args[0];
+  target_length = args->lengths[0];
+
+  if (!snip_info->snippet) {
+    for (i = 1; i < args->arg_count; i++) {
+      if (!args->args[i]) {
+        my_printf_error(ER_MRN_INVALID_NULL_VALUE_NUM,
+                        ER_MRN_INVALID_NULL_VALUE_STR, MYF(0),
+                        "mroonga_snippet() arguments");
+        goto error;
+      }
+    }
+
+    if (mrn_snippet_prepare(snip_info, args, NULL, &snippet)) {
+      goto error;
+    }
+  } else {
+    snippet = snip_info->snippet;
+  }
+
+  rc = grn_snip_exec(ctx, snippet, target, target_length,
+                     &n_results, &max_tagged_length);
+  if (rc) {
+    my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                    ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+    goto error;
+  }
+
+  result_str->length(0);
+  if (result_str->reserve((args->lengths[6] + args->lengths[7] +
+                          max_tagged_length) * n_results)) {
+    my_error(ER_OUT_OF_RESOURCES, MYF(0), HA_ERR_OUT_OF_MEM);
+    goto error;
+  }
+  for (i = 0; i < n_results; i++) {
+    result_str->q_append(args->args[6], args->lengths[6]);
+    rc = grn_snip_get_result(ctx, snippet, i,
+                             (char *) result_str->ptr() + result_str->length(),
+                             &result_length);
+    if (rc) {
+      my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                      ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+      goto error;
+    }
+    result_str->length(result_str->length() + result_length);
+    result_str->q_append(args->args[7], args->lengths[7]);
+  }
+
+  if (!snip_info->snippet) {
+    rc = grn_obj_close(ctx, snippet);
+    if (rc) {
+      my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                      ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+      goto error;
+    }
+  }
+
+  *length = result_str->length();
+  return (char *) result_str->ptr();
+
+error:
+  *error = 1;
+  return NULL;
+}
+
+MRN_API void mroonga_snippet_deinit(UDF_INIT *init)
+{
+  st_mrn_snip_info *snip_info = (st_mrn_snip_info *) init->ptr;
+  if (snip_info) {
+    if (snip_info->snippet) {
+      grn_obj_close(snip_info->ctx, snip_info->snippet);
+    }
+    MRN_STRING_FREE(snip_info->result_str);
+    if (!snip_info->use_shared_db) {
+      grn_obj_close(snip_info->ctx, snip_info->db);
+    }
+    mrn_context_pool->release(snip_info->ctx);
+    my_free(snip_info);
+  }
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/mrn_udf_snippet_html.cpp b/storage/mroonga/udf/mrn_udf_snippet_html.cpp
new file mode 100644
index 00000000..311c91bf
--- /dev/null
+++ b/storage/mroonga/udf/mrn_udf_snippet_html.cpp
@@ -0,0 +1,444 @@
+/* -*- c-basic-offset: 2; indent-tabs-mode: nil -*- */
+/*
+  Copyright(C) 2015-2017 Kouhei Sutou <kou@clear-code.com>
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA
+*/
+
+#include <mrn_mysql.h>
+#include <mrn_mysql_compat.h>
+#include <mrn_err.h>
+#include <mrn_encoding.hpp>
+#include <mrn_windows.hpp>
+#include <mrn_table.hpp>
+#include <mrn_macro.hpp>
+#include <mrn_database_manager.hpp>
+#include <mrn_context_pool.hpp>
+#include <mrn_variables.hpp>
+#include <mrn_query_parser.hpp>
+#include <mrn_current_thread.hpp>
+
+MRN_BEGIN_DECLS
+
+extern mrn::DatabaseManager *mrn_db_manager;
+extern mrn::ContextPool *mrn_context_pool;
+
+typedef struct st_mrn_snippet_html_info
+{
+  grn_ctx *ctx;
+  grn_obj *db;
+  bool use_shared_db;
+  grn_obj *snippet;
+  String result_str;
+  struct {
+    bool used;
+    grn_obj *table;
+    grn_obj *default_column;
+  } query_mode;
+} mrn_snippet_html_info;
+
+static my_bool mrn_snippet_html_prepare(mrn_snippet_html_info *info,
+                                        UDF_ARGS *args,
+                                        char *message,
+                                        grn_obj **snippet)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  grn_ctx *ctx = info->ctx;
+  int flags = GRN_SNIP_SKIP_LEADING_SPACES;
+  unsigned int width = 200;
+  unsigned int max_n_results = 3;
+  const char *open_tag = "<span class=\"keyword\">";
+  const char *close_tag = "</span>";
+  grn_snip_mapping *mapping = GRN_SNIP_MAPPING_HTML_ESCAPE;
+  grn_obj *expr = NULL;
+  String *result_str = &(info->result_str);
+
+  *snippet = NULL;
+
+  mrn::encoding::set_raw(ctx, system_charset_info);
+  if (!(system_charset_info->state & (MY_CS_BINSORT | MY_CS_CSSORT))) {
+    flags |= GRN_SNIP_NORMALIZE;
+  }
+
+  *snippet = grn_snip_open(ctx, flags,
+                           width, max_n_results,
+                           open_tag, strlen(open_tag),
+                           close_tag, strlen(close_tag),
+                           mapping);
+  if (ctx->rc != GRN_SUCCESS) {
+    if (message) {
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_snippet_html(): failed to open grn_snip: <%s>",
+               ctx->errbuf);
+    }
+    goto error;
+  }
+
+  if (info->query_mode.used) {
+    if (!info->query_mode.table) {
+      grn_obj *short_text;
+      short_text = grn_ctx_at(info->ctx, GRN_DB_SHORT_TEXT);
+      info->query_mode.table = grn_table_create(info->ctx,
+                                                NULL, 0, NULL,
+                                                GRN_TABLE_HASH_KEY,
+                                                short_text,
+                                                NULL);
+    }
+    if (!info->query_mode.default_column) {
+      info->query_mode.default_column =
+        grn_obj_column(info->ctx,
+                       info->query_mode.table,
+                       GRN_COLUMN_NAME_KEY,
+                       GRN_COLUMN_NAME_KEY_LEN);
+    }
+
+    grn_obj *record = NULL;
+    GRN_EXPR_CREATE_FOR_QUERY(info->ctx, info->query_mode.table, expr, record);
+    if (!expr) {
+      if (message) {
+        snprintf(message, MYSQL_ERRMSG_SIZE,
+                 "mroonga_snippet_html(): "
+                 "failed to create expression: <%s>",
+                 ctx->errbuf);
+      }
+      goto error;
+    }
+
+    mrn::QueryParser query_parser(info->ctx,
+                                  current_thd,
+                                  expr,
+                                  info->query_mode.default_column,
+                                  0,
+                                  NULL);
+    grn_rc rc = query_parser.parse(args->args[1], args->lengths[1]);
+    if (rc != GRN_SUCCESS) {
+      if (message) {
+        snprintf(message, MYSQL_ERRMSG_SIZE,
+                 "mroonga_snippet_html(): "
+                 "failed to parse query: <%s>",
+                 ctx->errbuf);
+      }
+      goto error;
+    }
+
+    rc = grn_expr_snip_add_conditions(info->ctx,
+                                      expr,
+                                      *snippet,
+                                      0,
+                                      NULL, NULL,
+                                      NULL, NULL);
+    if (rc != GRN_SUCCESS) {
+      if (message) {
+        snprintf(message, MYSQL_ERRMSG_SIZE,
+                 "mroonga_snippet_html(): "
+                 "failed to add conditions: <%s>",
+                 ctx->errbuf);
+      }
+      goto error;
+    }
+  } else {
+    unsigned int i;
+    for (i = 1; i < args->arg_count; ++i) {
+      if (!args->args[i]) {
+        continue;
+      }
+      grn_rc rc = grn_snip_add_cond(ctx, *snippet,
+                                    args->args[i], args->lengths[i],
+                                    NULL, 0,
+                                    NULL, 0);
+      if (rc != GRN_SUCCESS) {
+        if (message) {
+          snprintf(message, MYSQL_ERRMSG_SIZE,
+                   "mroonga_snippet_html(): "
+                   "failed to add a condition to grn_snip: <%s>",
+                   ctx->errbuf);
+        }
+        goto error;
+      }
+    }
+  }
+
+  result_str->set_charset(system_charset_info);
+  DBUG_RETURN(FALSE);
+
+error:
+  if (expr) {
+    grn_obj_close(ctx, expr);
+  }
+  if (*snippet) {
+    grn_obj_close(ctx, *snippet);
+  }
+  DBUG_RETURN(TRUE);
+}
+
+MRN_API my_bool mroonga_snippet_html_init(UDF_INIT *init,
+                                          UDF_ARGS *args,
+                                          char *message)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_snippet_html_info *info = NULL;
+
+  init->ptr = NULL;
+
+  if (args->arg_count < 1) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_snippet_html(): wrong number of arguments: %u for 1+",
+             args->arg_count);
+    goto error;
+  }
+
+
+  for (unsigned int i = 0; i < args->arg_count; ++i) {
+    switch (args->arg_type[i]) {
+    case STRING_RESULT:
+      /* OK */
+      break;
+    case REAL_RESULT:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_snippet_html(): all arguments must be string: "
+               "<%u>=<%g>",
+               i, *((double *)(args->args[i])));
+      goto error;
+      break;
+    case INT_RESULT:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_snippet_html(): all arguments must be string: "
+               "<%u>=<%lld>",
+               i, *((longlong *)(args->args[i])));
+      goto error;
+      break;
+    default:
+      snprintf(message, MYSQL_ERRMSG_SIZE,
+               "mroonga_snippet_html(): all arguments must be string: <%u>",
+               i);
+      goto error;
+      break;
+    }
+  }
+
+  init->maybe_null = 1;
+
+  info = (mrn_snippet_html_info *)mrn_my_malloc(sizeof(mrn_snippet_html_info),
+                                                MYF(MY_WME | MY_ZEROFILL));
+  if (!info) {
+    snprintf(message, MYSQL_ERRMSG_SIZE,
+             "mroonga_snippet_html(): failed to allocate memory");
+    goto error;
+  }
+
+  info->ctx = mrn_context_pool->pull();
+  {
+    const char *current_db_path = MRN_THD_DB_PATH(current_thd);
+    const char *action;
+    if (current_db_path) {
+      action = "open database";
+      mrn::Database *db;
+      int error = mrn_db_manager->open(current_db_path, &db);
+      if (error == 0) {
+        info->db = db->get();
+        grn_ctx_use(info->ctx, info->db);
+        info->use_shared_db = true;
+      }
+    } else {
+      action = "create anonymous database";
+      info->db = grn_db_create(info->ctx, NULL, NULL);
+      info->use_shared_db = false;
+    }
+    if (!info->db) {
+      sprintf(message,
+              "mroonga_snippet_html(): failed to %s: %s",
+              action,
+              info->ctx->errbuf);
+      goto error;
+    }
+  }
+
+  info->query_mode.used = FALSE;
+
+  if (args->arg_count == 2 &&
+      args->attribute_lengths[1] == strlen("query") &&
+      strncmp(args->attributes[1], "query", strlen("query")) == 0) {
+    info->query_mode.used = TRUE;
+    info->query_mode.table = NULL;
+    info->query_mode.default_column = NULL;
+  }
+
+  {
+    bool all_keywords_are_constant = TRUE;
+    for (unsigned int i = 1; i < args->arg_count; ++i) {
+      if (!args->args[i]) {
+        all_keywords_are_constant = FALSE;
+        break;
+      }
+    }
+
+    if (all_keywords_are_constant) {
+      if (mrn_snippet_html_prepare(info, args, message, &(info->snippet))) {
+        goto error;
+      }
+    } else {
+      info->snippet = NULL;
+    }
+  }
+
+  init->ptr = (char *)info;
+
+  DBUG_RETURN(FALSE);
+
+error:
+  if (info) {
+    if (!info->use_shared_db) {
+      grn_obj_close(info->ctx, info->db);
+    }
+    mrn_context_pool->release(info->ctx);
+    my_free(info);
+  }
+  DBUG_RETURN(TRUE);
+}
+
+MRN_API char *mroonga_snippet_html(UDF_INIT *init,
+                                   UDF_ARGS *args,
+                                   char *result,
+                                   unsigned long *length,
+                                   char *is_null,
+                                   char *error)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_snippet_html_info *info =
+    reinterpret_cast<mrn_snippet_html_info *>(init->ptr);
+
+  grn_ctx *ctx = info->ctx;
+  grn_obj *snippet = info->snippet;
+  String *result_str = &(info->result_str);
+
+  if (!args->args[0]) {
+    *is_null = 1;
+    DBUG_RETURN(NULL);
+  }
+
+  if (!snippet) {
+    if (mrn_snippet_html_prepare(info, args, NULL, &snippet)) {
+      goto error;
+    }
+  }
+
+  {
+    char *target = args->args[0];
+    unsigned int target_length = args->lengths[0];
+
+    unsigned int n_results, max_tagged_length;
+    {
+      grn_rc rc = grn_snip_exec(ctx, snippet, target, target_length,
+                                &n_results, &max_tagged_length);
+      if (rc != GRN_SUCCESS) {
+        my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                        ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+        goto error;
+      }
+    }
+
+    *is_null = 0;
+    result_str->length(0);
+
+    {
+      const char *start_tag = "<div class=\"snippet\">";
+      const char *end_tag = "</div>";
+      size_t start_tag_length = strlen(start_tag);
+      size_t end_tag_length = strlen(end_tag);
+      unsigned int max_length_per_snippet =
+        start_tag_length + end_tag_length + max_tagged_length;
+      if (result_str->reserve(max_length_per_snippet * n_results)) {
+        my_error(ER_OUT_OF_RESOURCES, MYF(0), HA_ERR_OUT_OF_MEM);
+        goto error;
+      }
+
+      for (unsigned int i = 0; i < n_results; ++i) {
+        result_str->q_append(start_tag, start_tag_length);
+
+        unsigned int result_length;
+        grn_rc rc =
+          grn_snip_get_result(ctx, snippet, i,
+                              (char *)result_str->ptr() + result_str->length(),
+                              &result_length);
+        if (rc) {
+          my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                          ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+          goto error;
+        }
+        result_str->length(result_str->length() + result_length);
+
+        result_str->q_append(end_tag, end_tag_length);
+      }
+    }
+
+    if (!info->snippet) {
+      grn_rc rc = grn_obj_close(ctx, snippet);
+      if (rc != GRN_SUCCESS) {
+        my_printf_error(ER_MRN_ERROR_FROM_GROONGA_NUM,
+                        ER_MRN_ERROR_FROM_GROONGA_STR, MYF(0), ctx->errbuf);
+        goto error;
+      }
+    }
+  }
+
+  *length = result_str->length();
+  DBUG_RETURN((char *)result_str->ptr());
+
+error:
+  if (!info->snippet && snippet) {
+    grn_obj_close(ctx, snippet);
+  }
+
+  *is_null = 1;
+  *error = 1;
+
+  DBUG_RETURN(NULL);
+}
+
+MRN_API void mroonga_snippet_html_deinit(UDF_INIT *init)
+{
+  MRN_DBUG_ENTER_FUNCTION();
+
+  mrn_snippet_html_info *info =
+    reinterpret_cast<mrn_snippet_html_info *>(init->ptr);
+  if (!info) {
+    DBUG_VOID_RETURN;
+  }
+
+  if (info->snippet) {
+    grn_obj_close(info->ctx, info->snippet);
+  }
+  if (info->query_mode.used) {
+    if (info->query_mode.default_column) {
+      grn_obj_close(info->ctx, info->query_mode.default_column);
+    }
+    if (info->query_mode.table) {
+      grn_obj_close(info->ctx, info->query_mode.table);
+    }
+  }
+  MRN_STRING_FREE(info->result_str);
+  if (!info->use_shared_db) {
+    grn_obj_close(info->ctx, info->db);
+  }
+  mrn_context_pool->release(info->ctx);
+  my_free(info);
+
+  DBUG_VOID_RETURN;
+}
+
+MRN_END_DECLS
diff --git a/storage/mroonga/udf/sources.am b/storage/mroonga/udf/sources.am
new file mode 100644
index 00000000..ac2f098e
--- /dev/null
+++ b/storage/mroonga/udf/sources.am
@@ -0,0 +1,9 @@
+libmrn_udf_la_SOURCES =				\
+	mrn_udf_last_insert_grn_id.cpp		\
+	mrn_udf_snippet.cpp			\
+	mrn_udf_snippet_html.cpp		\
+	mrn_udf_command.cpp			\
+	mrn_udf_escape.cpp			\
+	mrn_udf_normalize.cpp			\
+	mrn_udf_highlight_html.cpp		\
+	mrn_udf_query_expand.cpp