Compile schemarouter as C++

Compile schemarouter as C++ so that refactoring into more coherent parts
is easier.

server/modules/routing/schemarouter/CMakeLists.txt

@@ -1,4 +1,4 @@
-add_library(schemarouter SHARED schemarouter.c sharding_common.c)
+add_library(schemarouter SHARED schemarouter.cc)
 target_link_libraries(schemarouter maxscale-common)
 add_dependencies(schemarouter pcre2)
 set_target_properties(schemarouter PROPERTIES VERSION "1.0.0")

server/modules/routing/schemarouter/schemarouter.h

@@ -265,7 +265,7 @@ typedef struct backend_ref_st
     GWBUF*          map_queue;
     SERVER_REF*     bref_backend; /*< Backend server */
     DCB*            bref_dcb; /*< Backend DCB */
-    bref_state_t    bref_state; /*< State of the backend */
+    int             bref_state; /*< State of the backend */
     bool            bref_mapped; /*< Whether the backend has been mapped */
     bool            last_sescmd_replied;
     int             bref_num_result_wait; /*< Number of not yet received results */
@@ -335,7 +335,7 @@ struct schemarouter_session
                                 * mapped to the servers that contain them */
     char            connect_db[MYSQL_DATABASE_MAXLEN + 1]; /*< Database the user was trying to connect to */
     char            current_db[MYSQL_DATABASE_MAXLEN + 1]; /*< Current active database */
-    init_mask_t    init; /*< Initialization state bitmask */
+    int             init; /*< Initialization state bitmask */
     GWBUF*          queue; /*< Query that was received before the session was ready */
     DCB*            dcb_route; /*< Internal DCB used to trigger re-routing of buffers */
     DCB*            dcb_reply; /*< Internal DCB used to send replies to the client */

server/modules/routing/schemarouter/sharding_common.c

@@ -1,151 +0,0 @@
-/*
- * Copyright (c) 2016 MariaDB Corporation Ab
- *
- * Use of this software is governed by the Business Source License included
- * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
- *
- * Change Date: 2019-07-01
- *
- * On the date above, in accordance with the Business Source License, use
- * of this software will be governed by version 2 or later of the General
- * Public License.
- */
-
-#include "sharding_common.h"
-#include <maxscale/alloc.h>
-#include <maxscale/poll.h>
-
-/**
- * Extract the database name from a COM_INIT_DB or literal USE ... query.
- * @param buf Buffer with the database change query
- * @param str Pointer where the database name is copied
- * @return True for success, false for failure
- */
-bool extract_database(GWBUF* buf, char* str)
-{
-    uint8_t* packet;
-    char *saved, *tok, *query = NULL;
-    bool succp = true;
-    unsigned int plen;
-
-    packet = GWBUF_DATA(buf);
-    plen = gw_mysql_get_byte3(packet) - 1;
-
-    /** Copy database name from MySQL packet to session */
-    if (qc_get_operation(buf) == QUERY_OP_CHANGE_DB)
-    {
-        const char *delim = "` \n\t;";
-
-        query = modutil_get_SQL(buf);
-        tok = strtok_r(query, delim, &saved);
-
-        if (tok == NULL || strcasecmp(tok, "use") != 0)
-        {
-            MXS_ERROR("extract_database: Malformed chage database packet.");
-            succp = false;
-            goto retblock;
-        }
-
-        tok = strtok_r(NULL, delim, &saved);
-
-        if (tok == NULL)
-        {
-            MXS_ERROR("extract_database: Malformed change database packet.");
-            succp = false;
-            goto retblock;
-        }
-
-        strncpy(str, tok, MYSQL_DATABASE_MAXLEN);
-    }
-    else
-    {
-        memcpy(str, packet + 5, plen);
-        memset(str + plen, 0, 1);
-    }
-retblock:
-    MXS_FREE(query);
-    return succp;
-}
-
-/**
- * Create a fake error message from a DCB.
- * @param fail_str Custom error message
- * @param dcb DCB to use as the origin of the error
- */
-void create_error_reply(char* fail_str, DCB* dcb)
-{
-    MXS_INFO("change_current_db: failed to change database: %s", fail_str);
-    GWBUF* errbuf = modutil_create_mysql_err_msg(1, 0, 1049, "42000", fail_str);
-
-    if (errbuf == NULL)
-    {
-        MXS_ERROR("Creating buffer for error message failed.");
-        return;
-    }
-    /** Set flags that help router to identify session commands reply */
-    gwbuf_set_type(errbuf, GWBUF_TYPE_MYSQL);
-    gwbuf_set_type(errbuf, GWBUF_TYPE_SESCMD_RESPONSE);
-    gwbuf_set_type(errbuf, GWBUF_TYPE_RESPONSE_END);
-
-    poll_add_epollin_event_to_dcb(dcb,
-                                  errbuf);
-}
-
-/**
- * Read new database name from MYSQL_COM_INIT_DB packet or a literal USE ... COM_QUERY
- * packet, check that it exists in the hashtable and copy its name to MYSQL_session.
- *
- * @param dest Destination where the database name will be written
- * @param dbhash Hashtable containing valid databases
- * @param buf   Buffer containing the database change query
- *
- * @return true if new database is set, false if non-existent database was tried
- * to be set
- */
-bool change_current_db(char* dest,
-                       HASHTABLE* dbhash,
-                       GWBUF* buf)
-{
-    char* target;
-    bool succp;
-    char db[MYSQL_DATABASE_MAXLEN + 1];
-    if (GWBUF_LENGTH(buf) <= MYSQL_DATABASE_MAXLEN - 5)
-    {
-        /** Copy database name from MySQL packet to session */
-        if (!extract_database(buf, db))
-        {
-            succp = false;
-            goto retblock;
-        }
-        MXS_INFO("change_current_db: INIT_DB with database '%s'", db);
-        /**
-         * Update the session's active database only if it's in the hashtable.
-         * If it isn't found, send a custom error packet to the client.
-         */
-
-        if ((target = (char*)hashtable_fetch(dbhash, (char*)db)) == NULL)
-        {
-            succp = false;
-            goto retblock;
-        }
-        else
-        {
-            strcpy(dest, db);
-            MXS_INFO("change_current_db: database is on server: '%s'.", target);
-            succp = true;
-            goto retblock;
-        }
-    }
-    else
-    {
-        /** Create error message */
-        MXS_ERROR("change_current_db: failed to change database: Query buffer too large");
-        MXS_INFO("change_current_db: failed to change database: "
-                 "Query buffer too large [%ld bytes]", GWBUF_LENGTH(buf));
-        succp = false;
-        goto retblock;
-    }
-
-retblock:
-    return succp;
-}

server/modules/routing/schemarouter/sharding_common.h

@@ -1,35 +0,0 @@
-#pragma once
-#ifndef _SHARDING_COMMON_HG
-#define _SHARDING_COMMON_HG
-/*
- * Copyright (c) 2016 MariaDB Corporation Ab
- *
- * Use of this software is governed by the Business Source License included
- * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
- *
- * Change Date: 2019-07-01
- *
- * On the date above, in accordance with the Business Source License, use
- * of this software will be governed by version 2 or later of the General
- * Public License.
- */
-
-#include <maxscale/cdefs.h>
-#include <my_config.h>
-#include <poll.h>
-#include <maxscale/buffer.h>
-#include <maxscale/modutil.h>
-#include <maxscale/protocol/mysql.h>
-#include <maxscale/hashtable.h>
-#include <maxscale/log_manager.h>
-#include <maxscale/query_classifier.h>
-
-MXS_BEGIN_DECLS
-
-bool extract_database(GWBUF* buf, char* str);
-void create_error_reply(char* fail_str, DCB* dcb);
-bool change_current_db(char* dest, HASHTABLE* dbhash, GWBUF* buf);
-
-MXS_END_DECLS
-
-#endif