/* * Copyright 2017-2023 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. */ #ifndef PCMK__XML_INTERNAL__H # define PCMK__XML_INTERNAL__H /* * Internal-only wrappers for and extensions to libxml2 (libxslt) */ # include # include # include # include /* transitively imports qblog.h */ # include # include /*! * \brief Base for directing lib{xml2,xslt} log into standard libqb backend * * This macro implements the core of what can be needed for directing * libxml2 or libxslt error messaging into standard, preconfigured * libqb-backed log stream. * * It's a bit unfortunate that libxml2 (and more sparsely, also libxslt) * emits a single message by chunks (location is emitted separatedly from * the message itself), so we have to take the effort to combine these * chunks back to single message. Whether to do this or not is driven * with \p dechunk toggle. * * The form of a macro was chosen for implicit deriving of __FILE__, etc. * and also because static dechunking buffer should be differentiated per * library (here we assume different functions referring to this macro * will not ever be using both at once), preferably also per-library * context of use to avoid clashes altogether. * * Note that we cannot use qb_logt, because callsite data have to be known * at the moment of compilation, which it is not always the case -- xml_log * (and unfortunately there's no clear explanation of the fail to compile). * * Also note that there's no explicit guard against said libraries producing * never-newline-terminated chunks (which would just keep consuming memory), * as it's quite improbable. Termination of the program in between the * same-message chunks will raise a flag with valgrind and the likes, though. * * And lastly, regarding how dechunking combines with other non-message * parameters -- for \p priority, most important running specification * wins (possibly elevated to LOG_ERR in case of nonconformance with the * newline-termination "protocol"), \p dechunk is expected to always be * on once it was at the start, and the rest (\p postemit and \p prefix) * are picked directly from the last chunk entry finalizing the message * (also reasonable to always have it the same with all related entries). * * \param[in] priority Syslog priority for the message to be logged * \param[in] dechunk Whether to dechunk new-line terminated message * \param[in] postemit Code to be executed once message is sent out * \param[in] prefix How to prefix the message or NULL for raw passing * \param[in] fmt Format string as with printf-like functions * \param[in] ap Variable argument list to supplement \p fmt format string */ #define PCMK__XML_LOG_BASE(priority, dechunk, postemit, prefix, fmt, ap) \ do { \ if (!(dechunk) && (prefix) == NULL) { /* quick pass */ \ qb_log_from_external_source_va(__func__, __FILE__, (fmt), \ (priority), __LINE__, 0, (ap)); \ (void) (postemit); \ } else { \ int CXLB_len = 0; \ char *CXLB_buf = NULL; \ static int CXLB_buffer_len = 0; \ static char *CXLB_buffer = NULL; \ static uint8_t CXLB_priority = 0; \ \ CXLB_len = vasprintf(&CXLB_buf, (fmt), (ap)); \ \ if (CXLB_len <= 0 || CXLB_buf[CXLB_len - 1] == '\n' || !(dechunk)) { \ if (CXLB_len < 0) { \ CXLB_buf = (char *) "LOG CORRUPTION HAZARD"; /*we don't modify*/\ CXLB_priority = QB_MIN(CXLB_priority, LOG_ERR); \ } else if (CXLB_len > 0 /* && (dechunk) */ \ && CXLB_buf[CXLB_len - 1] == '\n') { \ CXLB_buf[CXLB_len - 1] = '\0'; \ } \ if (CXLB_buffer) { \ qb_log_from_external_source(__func__, __FILE__, "%s%s%s", \ CXLB_priority, __LINE__, 0, \ (prefix) != NULL ? (prefix) : "", \ CXLB_buffer, CXLB_buf); \ free(CXLB_buffer); \ } else { \ qb_log_from_external_source(__func__, __FILE__, "%s%s", \ (priority), __LINE__, 0, \ (prefix) != NULL ? (prefix) : "", \ CXLB_buf); \ } \ if (CXLB_len < 0) { \ CXLB_buf = NULL; /* restore temporary override */ \ } \ CXLB_buffer = NULL; \ CXLB_buffer_len = 0; \ (void) (postemit); \ \ } else if (CXLB_buffer == NULL) { \ CXLB_buffer_len = CXLB_len; \ CXLB_buffer = CXLB_buf; \ CXLB_buf = NULL; \ CXLB_priority = (priority); /* remember as a running severest */ \ \ } else { \ CXLB_buffer = realloc(CXLB_buffer, 1 + CXLB_buffer_len + CXLB_len); \ memcpy(CXLB_buffer + CXLB_buffer_len, CXLB_buf, CXLB_len); \ CXLB_buffer_len += CXLB_len; \ CXLB_buffer[CXLB_buffer_len] = '\0'; \ CXLB_priority = QB_MIN(CXLB_priority, (priority)); /* severest? */ \ } \ free(CXLB_buf); \ } \ } while (0) /* * \enum pcmk__xml_fmt_options * \brief Bit flags to control format in XML logs and dumps */ enum pcmk__xml_fmt_options { //! Exclude certain XML attributes (for calculating digests) pcmk__xml_fmt_filtered = (1 << 0), //! Include indentation and newlines pcmk__xml_fmt_pretty = (1 << 1), //! Include the opening tag of an XML element, and include XML comments pcmk__xml_fmt_open = (1 << 3), //! Include the children of an XML element pcmk__xml_fmt_children = (1 << 4), //! Include the closing tag of an XML element pcmk__xml_fmt_close = (1 << 5), //! Include XML text nodes pcmk__xml_fmt_text = (1 << 6), // @COMPAT Remove when v1 patchsets are removed //! Log a created XML subtree pcmk__xml_fmt_diff_plus = (1 << 7), // @COMPAT Remove when v1 patchsets are removed //! Log a removed XML subtree pcmk__xml_fmt_diff_minus = (1 << 8), // @COMPAT Remove when v1 patchsets are removed //! Log a minimal version of an XML diff (only showing the changes) pcmk__xml_fmt_diff_short = (1 << 9), }; int pcmk__xml_show(pcmk__output_t *out, const char *prefix, const xmlNode *data, int depth, uint32_t options); int pcmk__xml_show_changes(pcmk__output_t *out, const xmlNode *xml); /* XML search strings for guest, remote and pacemaker_remote nodes */ /* search string to find CIB resources entries for cluster nodes */ #define PCMK__XP_MEMBER_NODE_CONFIG \ "//" XML_TAG_CIB "/" XML_CIB_TAG_CONFIGURATION "/" XML_CIB_TAG_NODES \ "/" XML_CIB_TAG_NODE "[not(@type) or @type='member']" /* search string to find CIB resources entries for guest nodes */ #define PCMK__XP_GUEST_NODE_CONFIG \ "//" XML_TAG_CIB "//" XML_CIB_TAG_CONFIGURATION "//" XML_CIB_TAG_RESOURCE \ "//" XML_TAG_META_SETS "//" XML_CIB_TAG_NVPAIR \ "[@name='" XML_RSC_ATTR_REMOTE_NODE "']" /* search string to find CIB resources entries for remote nodes */ #define PCMK__XP_REMOTE_NODE_CONFIG \ "//" XML_TAG_CIB "//" XML_CIB_TAG_CONFIGURATION "//" XML_CIB_TAG_RESOURCE \ "[@type='remote'][@provider='pacemaker']" /* search string to find CIB node status entries for pacemaker_remote nodes */ #define PCMK__XP_REMOTE_NODE_STATUS \ "//" XML_TAG_CIB "//" XML_CIB_TAG_STATUS "//" XML_CIB_TAG_STATE \ "[@" XML_NODE_IS_REMOTE "='true']" /*! * \internal * \brief Serialize XML (using libxml) into provided descriptor * * \param[in] fd File descriptor to (piece-wise) write to * \param[in] cur XML subtree to proceed * * \return a standard Pacemaker return code */ int pcmk__xml2fd(int fd, xmlNode *cur); enum pcmk__xml_artefact_ns { pcmk__xml_artefact_ns_legacy_rng = 1, pcmk__xml_artefact_ns_legacy_xslt, pcmk__xml_artefact_ns_base_rng, pcmk__xml_artefact_ns_base_xslt, }; void pcmk__strip_xml_text(xmlNode *xml); const char *pcmk__xe_add_last_written(xmlNode *xe); xmlNode *pcmk__xe_match(const xmlNode *parent, const char *node_name, const char *attr_n, const char *attr_v); void pcmk__xe_remove_matching_attrs(xmlNode *element, bool (*match)(xmlAttrPtr, void *), void *user_data); GString *pcmk__element_xpath(const xmlNode *xml); /*! * \internal * \brief Get the root directory to scan XML artefacts of given kind for * * \param[in] ns governs the hierarchy nesting against the inherent root dir * * \return root directory to scan XML artefacts of given kind for */ char * pcmk__xml_artefact_root(enum pcmk__xml_artefact_ns ns); /*! * \internal * \brief Get the fully unwrapped path to particular XML artifact (RNG/XSLT) * * \param[in] ns denotes path forming details (parent dir, suffix) * \param[in] filespec symbolic file specification to be combined with * #artefact_ns to form the final path * \return unwrapped path to particular XML artifact (RNG/XSLT) */ char *pcmk__xml_artefact_path(enum pcmk__xml_artefact_ns ns, const char *filespec); /*! * \internal * \brief Check whether an XML element is of a particular type * * \param[in] xml XML element to compare * \param[in] name XML element name to compare * * \return \c true if \p xml is of type \p name, otherwise \c false */ static inline bool pcmk__xe_is(const xmlNode *xml, const char *name) { return (xml != NULL) && (xml->name != NULL) && (name != NULL) && (strcmp((const char *) xml->name, name) == 0); } /*! * \internal * \brief Return first non-text child node of an XML node * * \param[in] parent XML node to check * * \return First non-text child node of \p parent (or NULL if none) */ static inline xmlNode * pcmk__xml_first_child(const xmlNode *parent) { xmlNode *child = (parent? parent->children : NULL); while (child && (child->type == XML_TEXT_NODE)) { child = child->next; } return child; } /*! * \internal * \brief Return next non-text sibling node of an XML node * * \param[in] child XML node to check * * \return Next non-text sibling of \p child (or NULL if none) */ static inline xmlNode * pcmk__xml_next(const xmlNode *child) { xmlNode *next = (child? child->next : NULL); while (next && (next->type == XML_TEXT_NODE)) { next = next->next; } return next; } /*! * \internal * \brief Return first non-text child element of an XML node * * \param[in] parent XML node to check * * \return First child element of \p parent (or NULL if none) */ static inline xmlNode * pcmk__xe_first_child(const xmlNode *parent) { xmlNode *child = (parent? parent->children : NULL); while (child && (child->type != XML_ELEMENT_NODE)) { child = child->next; } return child; } /*! * \internal * \brief Return next non-text sibling element of an XML element * * \param[in] child XML element to check * * \return Next sibling element of \p child (or NULL if none) */ static inline xmlNode * pcmk__xe_next(const xmlNode *child) { xmlNode *next = child? child->next : NULL; while (next && (next->type != XML_ELEMENT_NODE)) { next = next->next; } return next; } /*! * \internal * \brief Like pcmk__xe_set_props, but takes a va_list instead of * arguments directly. * * \param[in,out] node XML to add attributes to * \param[in] pairs NULL-terminated list of name/value pairs to add */ void pcmk__xe_set_propv(xmlNodePtr node, va_list pairs); /*! * \internal * \brief Add a NULL-terminated list of name/value pairs to the given * XML node as properties. * * \param[in,out] node XML node to add properties to * \param[in] ... NULL-terminated list of name/value pairs * * \note A NULL name terminates the arguments; a NULL value will be skipped. */ void pcmk__xe_set_props(xmlNodePtr node, ...) G_GNUC_NULL_TERMINATED; /*! * \internal * \brief Get first attribute of an XML element * * \param[in] xe XML element to check * * \return First attribute of \p xe (or NULL if \p xe is NULL or has none) */ static inline xmlAttr * pcmk__xe_first_attr(const xmlNode *xe) { return (xe == NULL)? NULL : xe->properties; } /*! * \internal * \brief Extract the ID attribute from an XML element * * \param[in] xpath String to search * \param[in] node Node to get the ID for * * \return ID attribute of \p node in xpath string \p xpath */ char * pcmk__xpath_node_id(const char *xpath, const char *node); /* internal XML-related utilities */ enum xml_private_flags { pcmk__xf_none = 0x0000, pcmk__xf_dirty = 0x0001, pcmk__xf_deleted = 0x0002, pcmk__xf_created = 0x0004, pcmk__xf_modified = 0x0008, pcmk__xf_tracking = 0x0010, pcmk__xf_processed = 0x0020, pcmk__xf_skip = 0x0040, pcmk__xf_moved = 0x0080, pcmk__xf_acl_enabled = 0x0100, pcmk__xf_acl_read = 0x0200, pcmk__xf_acl_write = 0x0400, pcmk__xf_acl_deny = 0x0800, pcmk__xf_acl_create = 0x1000, pcmk__xf_acl_denied = 0x2000, pcmk__xf_lazy = 0x4000, }; void pcmk__set_xml_doc_flag(xmlNode *xml, enum xml_private_flags flag); /*! * \internal * \brief Iterate over child elements of \p xml * * This function iterates over the children of \p xml, performing the * callback function \p handler on each node. If the callback returns * a value other than pcmk_rc_ok, the iteration stops and the value is * returned. It is therefore possible that not all children will be * visited. * * \param[in,out] xml The starting XML node. Can be NULL. * \param[in] child_element_name The name that the node must match in order * for \p handler to be run. If NULL, all * child elements will match. * \param[in] handler The callback function. * \param[in,out] userdata User data to pass to the callback function. * Can be NULL. * * \return Standard Pacemaker return code */ int pcmk__xe_foreach_child(xmlNode *xml, const char *child_element_name, int (*handler)(xmlNode *xml, void *userdata), void *userdata); static inline const char * pcmk__xml_attr_value(const xmlAttr *attr) { return ((attr == NULL) || (attr->children == NULL))? NULL : (const char *) attr->children->content; } gboolean pcmk__validate_xml(xmlNode *xml_blob, const char *validation, xmlRelaxNGValidityErrorFunc error_handler, void *error_handler_context); #endif // PCMK__XML_INTERNAL__H