/*

 * Original copyright 2004 International Business Machines

 * Later changes copyright 2008-2025 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>

#include <libxml/tree.h>    // xmlNode

#include <crm/common/xml.h>

#include <crm/common/cib.h>

#include <crm/common/cib_internal.h>

/*

 * Functions to help find particular sections of the CIB

 */

// Map CIB element names to their parent elements and XPath searches

static struct {

    const char *name;   // Name of this CIB element

    const char *parent; // CIB element that this element is a child of

    const char *path;   // XPath to find this CIB element

} cib_sections[] = {

    {

        // This first entry is also the default if a NULL is compared

        PCMK_XE_CIB,

        NULL,

        "//" PCMK_XE_CIB

    },

    {

        PCMK_XE_STATUS,

        "/" PCMK_XE_CIB,

        "//" PCMK_XE_CIB "/" PCMK_XE_STATUS

    },

    {

        PCMK_XE_CONFIGURATION,

        "/" PCMK_XE_CIB,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION

    },

    {

        PCMK_XE_CRM_CONFIG,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_CRM_CONFIG

    },

    {

        PCMK_XE_NODES,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_NODES

    },

    {

        PCMK_XE_RESOURCES,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_RESOURCES

    },

    {

        PCMK_XE_CONSTRAINTS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_CONSTRAINTS

    },

    {

        PCMK_XE_OP_DEFAULTS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_OP_DEFAULTS

    },

    {

        PCMK_XE_RSC_DEFAULTS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_RSC_DEFAULTS

    },

    {

        PCMK_XE_ACLS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_ACLS

    },

    {

        PCMK_XE_FENCING_TOPOLOGY,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_FENCING_TOPOLOGY

    },

    {

        PCMK_XE_TAGS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_TAGS

    },

    {

        PCMK_XE_ALERTS,

        "/" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION,

        "//" PCMK_XE_CIB "/" PCMK_XE_CONFIGURATION "/" PCMK_XE_ALERTS

    },

    {

        PCMK__XE_ALL,

        NULL,

        "//" PCMK_XE_CIB

    },

};

/*!

 * \brief Get the relative XPath needed to find a specified CIB element name

 *

 * \param[in] element_name  Name of CIB element

 *

 * \return XPath for finding \p element_name in CIB XML (or NULL if unknown)

 * \note The return value is constant and should not be freed.

 */

const char *

pcmk_cib_xpath_for(const char *element_name)

{

    for (int lpc = 0; lpc < PCMK__NELEM(cib_sections); lpc++) {

        // A NULL element_name will match the first entry

        if (pcmk__str_eq(element_name, cib_sections[lpc].name,

                         pcmk__str_null_matches)) {

            return cib_sections[lpc].path;

        }

    }

    return NULL;

}

/*!

 * \internal

 * \brief Get the absolute XPath needed to find a specified CIB element name

 *

 * \param[in] element  Name of CIB element

 *

 * \return XPath for finding \p element in CIB XML (or \c NULL if unknown)

 */

const char *

pcmk__cib_abs_xpath_for(const char *element)

{

    const char *xpath = pcmk_cib_xpath_for(element);

    // XPaths returned by pcmk_cib_xpath_for() are relative (starting with "//")

    return ((xpath != NULL)? (xpath + 1) : NULL);

}

/*!

 * \brief Get the parent element name of a given CIB element name

 *

 * \param[in] element_name  Name of CIB element

 *

 * \return Parent element of \p element_name (or NULL if none or unknown)

 * \note The return value is constant and should not be freed.

 */

const char *

pcmk_cib_parent_name_for(const char *element_name)

{

    for (int lpc = 0; lpc < PCMK__NELEM(cib_sections); lpc++) {

        // A NULL element_name will match the first entry

        if (pcmk__str_eq(element_name, cib_sections[lpc].name,

                         pcmk__str_null_matches)) {

            return cib_sections[lpc].parent;

        }

    }

    return NULL;

}

/*!

 * \brief Find an element in the CIB

 *

 * \param[in,out] cib           Top-level CIB XML to search

 * \param[in]     element_name  Name of CIB element to search for

 *

 * \return XML element in \p cib corresponding to \p element_name

 *         (or \p cib itself if element is unknown or not found)

 */

xmlNode *

pcmk_find_cib_element(xmlNode *cib, const char *element_name)

{

    return pcmk__xpath_find_one(cib->doc, pcmk_cib_xpath_for(element_name),

                                LOG_TRACE);

}

/*!

 * \internal

 * \brief Check that the feature set in the CIB is supported on this node

 *

 * \param[in] new_version   PCMK_XA_CRM_FEATURE_SET attribute from the CIB

 */

int

pcmk__check_feature_set(const char *cib_version)

{

    if ((cib_version != NULL)

        && (pcmk__compare_versions(cib_version, CRM_FEATURE_SET) > 0)) {

        return EPROTONOSUPPORT;

    }

    return pcmk_rc_ok;

}