/*

 * Copyright 2024 the Pacemaker project contributors

 *

 * The version control history for this file may have further details.

 *

 * This source code is licensed under the GNU Lesser General Public License

 * version 2.1 or later (LGPLv2.1+) WITHOUT ANY WARRANTY.

 */

#include <crm_internal.h>

#include <stdio.h>      // NULL

#include <crm/crm.h>

/* Each Pacemaker subdaemon offers an IPC interface, and most exchange cluster

 * messages as well. Particular names need to be used for logging, connecting

 * IPC, and IPC/cluster message types.

 *

 * This array is indexed by enum pcmk_ipc_server and gathers all those names for

 * easier mapping. Most members are lists with the first value listed being the

 * "main" one returned if another value is mapped to it.

 *

 * @COMPAT Ideally, we'd use a single string (such as the server's

 * crm_system_name) as the sole IPC name and sole message type for each server,

 * making most of this unnecessary. However, backward compatiblity with older

 * nodes involved in a rolling upgrade or Pacemaker Remote connection would

 * be a nightmare: we'd have to add duplicate message attributes, struct

 * members, and libqb IPC server endpoints for both the old and new names, and

 * could drop the old names only after we no longer supported connections with

 * older nodes.

 */

static struct {

    const char *log_name;         // Readable server name for use in logs

    const char *system_names[2];  // crm_system_name values (subdaemon names)

    const char *ipc_names[3];     // libqb IPC names used to contact server

    const char *message_types[3]; // IPC/cluster message types sent to server

} server_info[] = {

    [pcmk_ipc_unknown] = {

        NULL,

        { NULL, NULL, },

        { NULL, NULL, NULL, },

        { NULL, NULL, NULL, },

    },

    [pcmk_ipc_attrd] = {

        "attribute manager",

        { PCMK__SERVER_ATTRD, NULL, },

        { PCMK__VALUE_ATTRD, NULL, NULL, },

        { PCMK__VALUE_ATTRD, NULL, NULL, },

    },

    [pcmk_ipc_based] = {

        "CIB manager",

        { PCMK__SERVER_BASED, NULL, },

        { PCMK__SERVER_BASED_RW, PCMK__SERVER_BASED_RO,

          PCMK__SERVER_BASED_SHM, },

        { CRM_SYSTEM_CIB, NULL, NULL, },

    },

    [pcmk_ipc_controld] = {

        "controller",

        { PCMK__SERVER_CONTROLD, NULL, },

        { PCMK__VALUE_CRMD, NULL, NULL, },

        { PCMK__VALUE_CRMD, CRM_SYSTEM_DC, CRM_SYSTEM_TENGINE, },

    },

    [pcmk_ipc_execd] = {

        "executor",

        { PCMK__SERVER_EXECD, PCMK__SERVER_REMOTED, },

        { PCMK__VALUE_LRMD, NULL, NULL, },

        { PCMK__VALUE_LRMD, NULL, NULL, },

    },

    [pcmk_ipc_fenced] = {

        "fencer",

        { PCMK__SERVER_FENCED, NULL, },

        { PCMK__VALUE_STONITH_NG, NULL, NULL, },

        { PCMK__VALUE_STONITH_NG, NULL, NULL, },

    },

    [pcmk_ipc_pacemakerd] = {

        "launcher",

        { PCMK__SERVER_PACEMAKERD, NULL, },

        { CRM_SYSTEM_MCP, NULL, NULL, },

        { CRM_SYSTEM_MCP, NULL, NULL, },

    },

    [pcmk_ipc_schedulerd] = {

        "scheduler",

        { PCMK__SERVER_SCHEDULERD, NULL, },

        { CRM_SYSTEM_PENGINE, NULL, NULL, },

        { CRM_SYSTEM_PENGINE, NULL, NULL, },

    },

};

/*!

 * \internal

 * \brief Return server's (primary) system name

 *

 * \param[in] server  Server to get system name for

 *

 * \return System name for server (or NULL if invalid)

 * \note If \p server is an \c enum pcmk_ipc_server value other than

 *       \c pcmk_ipc_unknown, the return value is guaranteed to be non-NULL.

 */

const char *

pcmk__server_name(enum pcmk_ipc_server server)

{

    CRM_CHECK((server > 0) && (server < PCMK__NELEM(server_info)),

              return NULL);

    return server_info[server].system_names[0];

}

/*!

 * \internal

 * \brief Return a readable description of server for logging

 *

 * \param[in] server  Server to get log name for

 *

 * \return Log name for server (or NULL if invalid)

 * \note If \p server is an \c enum pcmk_ipc_server value other than

 *       \c pcmk_ipc_unknown, the return value is guaranteed to be non-NULL.

 */

const char *

pcmk__server_log_name(enum pcmk_ipc_server server)

{

    CRM_CHECK((server > 0) && (server < PCMK__NELEM(server_info)),

              return NULL);

    return server_info[server].log_name;

}

/*!

 * \internal

 * \brief Return the (primary) IPC endpoint name for a server

 *

 * \param[in] server  Server to get IPC endpoint for

 *

 * \return IPC endpoint for server (or NULL if invalid)

 * \note If \p server is an \c enum pcmk_ipc_server value other than

 *       \c pcmk_ipc_unknown, the return value is guaranteed to be non-NULL.

 */

const char *

pcmk__server_ipc_name(enum pcmk_ipc_server server)

{

    CRM_CHECK((server > 0) && (server < PCMK__NELEM(server_info)),

              return NULL);

    return server_info[server].ipc_names[0];

}

/*!

 * \internal

 * \brief Return the (primary) message type for a server

 *

 * \param[in] server  Server to get message type for

 *

 * \return Message type for server (or NULL if invalid)

 * \note If \p server is an \c enum pcmk_ipc_server value other than

 *       \c pcmk_ipc_unknown, the return value is guaranteed to be non-NULL.

 */

const char *

pcmk__server_message_type(enum pcmk_ipc_server server)

{

    CRM_CHECK((server > 0) && (server < PCMK__NELEM(server_info)),

              return NULL);

    return server_info[server].message_types[0];

}

/*!

 * \internal

 * \brief Get the server corresponding to a name

 *

 * \param[in] text  A system name, IPC endpoint name, or message type

 *

 * \return Server corresponding to \p text

 */

enum pcmk_ipc_server

pcmk__parse_server(const char *text)

{

    if (text == NULL) {

        return pcmk_ipc_unknown;

    }

    for (enum pcmk_ipc_server server = pcmk_ipc_attrd;

         server <= pcmk_ipc_schedulerd; ++server) {

        int name;

        for (name = 0;

             (name < 2) && (server_info[server].system_names[name] != NULL);

             ++name) {

            if (strcmp(text, server_info[server].system_names[name]) == 0) {

                return server;

            }

        }

        for (name = 0;

             (name < 3) && (server_info[server].ipc_names[name] != NULL);

             ++name) {

            if (strcmp(text, server_info[server].ipc_names[name]) == 0) {

                return server;

            }

        }

        for (name = 0;

             (name < 3) && (server_info[server].message_types[name] != NULL);

             ++name) {

            if (strcmp(text, server_info[server].message_types[name]) == 0) {

                return server;

            }

        }

    }

    return pcmk_ipc_unknown;

}