/*
	 * Copyright 2004-2023 the Pacemaker project contributors
	 *
	 * The version control history for this file may have further details.
	 *
	 * This source code is licensed under the GNU General Public License version 2
	 * or later (GPLv2+) WITHOUT ANY WARRANTY.
	 */
	
	#include <crm_internal.h>
	
	#include <stdio.h>
	#include <unistd.h>
	#include <string.h>
	#include <stdlib.h>
	#include <errno.h>
	#include <fcntl.h>
	#include <dirent.h>
	
	#include <sys/param.h>
	#include <sys/types.h>
	#include <sys/wait.h>
	#include <sys/stat.h>
	
	#include <glib.h>
	#include <libxml/tree.h>
	
	#include <crm/crm.h>
	
	#include <crm/cib.h>
	#include <crm/common/util.h>
	#include <crm/msg_xml.h>
	#include <crm/common/xml.h>
	#include <crm/cib/internal.h>
	#include <crm/cluster.h>
	
	#include <pacemaker-based.h>
	
	crm_trigger_t *cib_writer = NULL;
	
	int write_cib_contents(gpointer p);
	
	static void
	cib_rename(const char *old)
	{
	    int new_fd;
	    char *new = crm_strdup_printf("%s/cib.auto.XXXXXX", cib_root);
	
	    umask(S_IWGRP | S_IWOTH | S_IROTH);

	    new_fd = mkstemp(new);
	

	    if ((new_fd < 0) || (rename(old, new) < 0)) {
	        crm_err("Couldn't archive unusable file %s (disabling disk writes and continuing)",
	                old);
	        cib_writes_enabled = FALSE;
	    } else {
	        crm_err("Archived unusable file %s as %s", old, new);
	    }
	

	    if (new_fd > 0) {
	        close(new_fd);
	    }
	    free(new);

	}
	
	/*
	 * It is the callers responsibility to free the output of this function
	 */
	
	static xmlNode *
	retrieveCib(const char *filename, const char *sigfile)
	{
	    xmlNode *root = NULL;
	
	    crm_info("Reading cluster configuration file %s (digest: %s)",
	             filename, sigfile);
	    switch (cib_file_read_and_verify(filename, sigfile, &root)) {
	        case -pcmk_err_cib_corrupt:
	            crm_warn("Continuing but %s will NOT be used.", filename);
	            break;
	
	        case -pcmk_err_cib_modified:
	            /* Archive the original files so the contents are not lost */
	            crm_warn("Continuing but %s will NOT be used.", filename);
	            cib_rename(filename);
	            cib_rename(sigfile);
	            break;
	    }
	    return root;
	}
	
	/*
	 * for OSs without support for direntry->d_type, like Solaris
	 */
	#ifndef DT_UNKNOWN
	# define DT_UNKNOWN     0
	# define DT_FIFO        1
	# define DT_CHR         2
	# define DT_DIR         4
	# define DT_BLK         6
	# define DT_REG         8
	# define DT_LNK         10
	# define DT_SOCK        12
	# define DT_WHT         14
	#endif /*DT_UNKNOWN*/
	
	static int cib_archive_filter(const struct dirent * a)
	{
	    int rc = 0;
	    /* Looking for regular files (d_type = 8) starting with 'cib-' and not ending in .sig */
	    struct stat s;
	    char *a_path = crm_strdup_printf("%s/%s", cib_root, a->d_name);
	
	    if(stat(a_path, &s) != 0) {
	        rc = errno;
	        crm_trace("%s - stat failed: %s (%d)", a->d_name, pcmk_rc_str(rc), rc);
	        rc = 0;
	
	    } else if ((s.st_mode & S_IFREG) != S_IFREG) {
	        unsigned char dtype;
	#ifdef HAVE_STRUCT_DIRENT_D_TYPE
	        dtype = a->d_type;
	#else
	        switch (s.st_mode & S_IFMT) {
	            case S_IFREG:  dtype = DT_REG;      break;
	            case S_IFDIR:  dtype = DT_DIR;      break;
	            case S_IFCHR:  dtype = DT_CHR;      break;
	            case S_IFBLK:  dtype = DT_BLK;      break;
	            case S_IFLNK:  dtype = DT_LNK;      break;
	            case S_IFIFO:  dtype = DT_FIFO;     break;
	            case S_IFSOCK: dtype = DT_SOCK;     break;
	            default:       dtype = DT_UNKNOWN;  break;
	        }
	#endif
	         crm_trace("%s - wrong type (%d)", a->d_name, dtype);
	
	    } else if(strstr(a->d_name, "cib-") != a->d_name) {
	        crm_trace("%s - wrong prefix", a->d_name);
	
	    } else if (pcmk__ends_with_ext(a->d_name, ".sig")) {
	        crm_trace("%s - wrong suffix", a->d_name);
	
	    } else {
	        crm_debug("%s - candidate", a->d_name);
	        rc = 1;
	    }
	
	    free(a_path);
	    return rc;
	}
	
	static int cib_archive_sort(const struct dirent ** a, const struct dirent **b)
	{
	    /* Order by creation date - most recently created file first */
	    int rc = 0;
	    struct stat buf;
	
	    time_t a_age = 0;
	    time_t b_age = 0;
	
	    char *a_path = crm_strdup_printf("%s/%s", cib_root, a[0]->d_name);
	    char *b_path = crm_strdup_printf("%s/%s", cib_root, b[0]->d_name);
	
	    if(stat(a_path, &buf) == 0) {
	        a_age = buf.st_ctime;
	    }
	    if(stat(b_path, &buf) == 0) {
	        b_age = buf.st_ctime;
	    }
	
	    free(a_path);
	    free(b_path);
	
	    if(a_age > b_age) {
	        rc = 1;
	    } else if(a_age < b_age) {
	        rc = -1;
	    }
	
	    crm_trace("%s (%lu) vs. %s (%lu) : %d",
		a[0]->d_name, (unsigned long)a_age,
		b[0]->d_name, (unsigned long)b_age, rc);
	    return rc;
	}
	
	xmlNode *
	readCibXmlFile(const char *dir, const char *file, gboolean discard_status)
	{
	    struct dirent **namelist = NULL;
	
	    int lpc = 0;
	    char *sigfile = NULL;
	    char *sigfilepath = NULL;
	    char *filename = NULL;
	    const char *name = NULL;
	    const char *value = NULL;
	    const char *validation = NULL;
	    const char *use_valgrind = pcmk__env_option(PCMK__ENV_VALGRIND_ENABLED);
	
	    xmlNode *root = NULL;
	    xmlNode *status = NULL;
	
	    sigfile = crm_strdup_printf("%s.sig", file);
	    if (pcmk__daemon_can_write(dir, file) == FALSE
	            || pcmk__daemon_can_write(dir, sigfile) == FALSE) {
	        cib_status = -EACCES;
	        return NULL;
	    }
	
	    filename = crm_strdup_printf("%s/%s", dir, file);
	    sigfilepath = crm_strdup_printf("%s/%s", dir, sigfile);
	    free(sigfile);
	
	    cib_status = pcmk_ok;
	    root = retrieveCib(filename, sigfilepath);
	    free(filename);
	    free(sigfilepath);
	
	    if (root == NULL) {
	        crm_warn("Primary configuration corrupt or unusable, trying backups in %s", cib_root);
	        lpc = scandir(cib_root, &namelist, cib_archive_filter, cib_archive_sort);
	        if (lpc < 0) {
	            crm_err("scandir(%s) failed: %s", cib_root, pcmk_rc_str(errno));
	        }
	    }
	
	    while (root == NULL && lpc > 1) {
	        crm_debug("Testing %d candidates", lpc);
	
	        lpc--;
	
	        filename = crm_strdup_printf("%s/%s", cib_root, namelist[lpc]->d_name);
	        sigfile = crm_strdup_printf("%s.sig", filename);
	
	        crm_info("Reading cluster configuration file %s (digest: %s)",
	                 filename, sigfile);
	        if (cib_file_read_and_verify(filename, sigfile, &root) < 0) {
	            crm_warn("Continuing but %s will NOT be used.", filename);
	        } else {
	            crm_notice("Continuing with last valid configuration archive: %s", filename);
	        }
	
	        free(namelist[lpc]);
	        free(filename);
	        free(sigfile);
	    }
	    free(namelist);
	
	    if (root == NULL) {
	        root = createEmptyCib(0);
	        crm_warn("Continuing with an empty configuration.");
	    }
	
	    if (cib_writes_enabled && use_valgrind &&
	        (crm_is_true(use_valgrind) || strstr(use_valgrind, "pacemaker-based"))) {
	
	        cib_writes_enabled = FALSE;
	        crm_err("*** Disabling disk writes to avoid confusing Valgrind ***");
	    }
	
	    status = find_xml_node(root, XML_CIB_TAG_STATUS, FALSE);
	    if (discard_status && status != NULL) {
	        /* strip out the status section if there is one */
	        free_xml(status);
	        status = NULL;
	    }
	    if (status == NULL) {
	        create_xml_node(root, XML_CIB_TAG_STATUS);
	    }
	
	    /* Do this before schema validation happens */
	
	    /* fill in some defaults */
	    name = XML_ATTR_GENERATION_ADMIN;
	    value = crm_element_value(root, name);
	    if (value == NULL) {
	        crm_warn("No value for %s was specified in the configuration.", name);
	        crm_warn("The recommended course of action is to shutdown,"
	                 " run crm_verify and fix any errors it reports.");
	        crm_warn("We will default to zero and continue but may get"
	                 " confused about which configuration to use if"
	                 " multiple nodes are powered up at the same time.");
	        crm_xml_add_int(root, name, 0);
	    }
	
	    name = XML_ATTR_GENERATION;
	    value = crm_element_value(root, name);
	    if (value == NULL) {
	        crm_xml_add_int(root, name, 0);
	    }
	
	    name = XML_ATTR_NUMUPDATES;
	    value = crm_element_value(root, name);
	    if (value == NULL) {
	        crm_xml_add_int(root, name, 0);
	    }
	
	    // Unset (DC should set appropriate value)
	    xml_remove_prop(root, XML_ATTR_DC_UUID);
	
	    if (discard_status) {
	        crm_log_xml_trace(root, "[on-disk]");
	    }
	
	    validation = crm_element_value(root, XML_ATTR_VALIDATION);
	    if (validate_xml(root, NULL, TRUE) == FALSE) {
	        crm_err("CIB does not validate with %s",
	                pcmk__s(validation, "no schema specified"));
	        cib_status = -pcmk_err_schema_validation;
	
	    } else if (validation == NULL) {
	        int version = 0;
	
	        update_validation(&root, &version, 0, FALSE, FALSE);
	        if (version > 0) {
	            crm_notice("Enabling %s validation on"
	                       " the existing (sane) configuration", get_schema_name(version));
	        } else {
	            crm_err("CIB does not validate with any known schema");
	            cib_status = -pcmk_err_schema_validation;
	        }
	    }
	
	    return root;
	}
	
	gboolean
	uninitializeCib(void)
	{
	    xmlNode *tmp_cib = the_cib;
	
	    if (tmp_cib == NULL) {
	        crm_debug("The CIB has already been deallocated.");
	        return FALSE;
	    }
	
	    the_cib = NULL;
	
	    crm_debug("Deallocating the CIB.");
	
	    free_xml(tmp_cib);
	
	    crm_debug("The CIB has been deallocated.");
	
	    return TRUE;
	}
	
	/*
	 * This method will free the old CIB pointer on success and the new one
	 * on failure.
	 */
	int
	activateCibXml(xmlNode * new_cib, gboolean to_disk, const char *op)
	{
	    if (new_cib) {
	        xmlNode *saved_cib = the_cib;
	
	        CRM_ASSERT(new_cib != saved_cib);
	        the_cib = new_cib;
	        free_xml(saved_cib);
	        if (cib_writes_enabled && cib_status == pcmk_ok && to_disk) {
	            crm_debug("Triggering CIB write for %s op", op);
	            mainloop_set_trigger(cib_writer);
	        }
	        return pcmk_ok;
	    }
	
	    crm_err("Ignoring invalid CIB");
	    if (the_cib) {
	        crm_warn("Reverting to last known CIB");
	    } else {
	        crm_crit("Could not write out new CIB and no saved version to revert to");
	    }
	    return -ENODATA;
	}
	
	static void
	cib_diskwrite_complete(mainloop_child_t * p, pid_t pid, int core, int signo, int exitcode)
	{
	    const char *errmsg = "Could not write CIB to disk";
	
	    if ((exitcode != 0) && cib_writes_enabled) {
	        cib_writes_enabled = FALSE;
	        errmsg = "Disabling CIB disk writes after failure";
	    }
	
	    if ((signo == 0) && (exitcode == 0)) {
	        crm_trace("Disk write [%d] succeeded", (int) pid);
	
	    } else if (signo == 0) {
	        crm_err("%s: process %d exited %d", errmsg, (int) pid, exitcode);
	
	    } else {
	        crm_err("%s: process %d terminated with signal %d (%s)%s",
	                errmsg, (int) pid, signo, strsignal(signo),
	                (core? " and dumped core" : ""));
	    }
	
	    mainloop_trigger_complete(cib_writer);
	}
	
	int
	write_cib_contents(gpointer p)
	{
	    int exit_rc = pcmk_ok;
	    xmlNode *cib_local = NULL;
	
	    /* Make a copy of the CIB to write (possibly in a forked child) */
	    if (p) {
	        /* Synchronous write out */
	        cib_local = copy_xml(p);
	
	    } else {
	        int pid = 0;
	        int bb_state = qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_STATE_GET, 0);
	
	        /* Turn it off before the fork() to avoid:
	         * - 2 processes writing to the same shared mem
	         * - the child needing to disable it
	         *   (which would close it from underneath the parent)
	         * This way, the shared mem files are already closed
	         */
	        qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_ENABLED, QB_FALSE);
	
	        pid = fork();
	        if (pid < 0) {
	            crm_err("Disabling disk writes after fork failure: %s", pcmk_rc_str(errno));
	            cib_writes_enabled = FALSE;
	            return FALSE;
	        }
	
	        if (pid) {
	            /* Parent */
	            mainloop_child_add(pid, 0, "disk-writer", NULL, cib_diskwrite_complete);
	            if (bb_state == QB_LOG_STATE_ENABLED) {
	                /* Re-enable now that it it safe */
	                qb_log_ctl(QB_LOG_BLACKBOX, QB_LOG_CONF_ENABLED, QB_TRUE);
	            }
	
	            return -1;          /* -1 means 'still work to do' */
	        }
	
	        /* Asynchronous write-out after a fork() */
	
	        /* In theory, we can scribble on the_cib here and not affect the parent,
	         * but let's be safe anyway.
	         */
	        cib_local = copy_xml(the_cib);
	    }
	
	    /* Write the CIB */
	    exit_rc = cib_file_write_with_digest(cib_local, cib_root, "cib.xml");
	
	    /* A nonzero exit code will cause further writes to be disabled */
	    free_xml(cib_local);
	    if (p == NULL) {
	        crm_exit_t exit_code = CRM_EX_OK;
	
	        switch (exit_rc) {
	            case pcmk_ok:
	                exit_code = CRM_EX_OK;
	                break;
	            case pcmk_err_cib_modified:
	                exit_code = CRM_EX_DIGEST; // Existing CIB doesn't match digest
	                break;
	            case pcmk_err_cib_backup: // Existing CIB couldn't be backed up
	            case pcmk_err_cib_save:   // New CIB couldn't be saved
	                exit_code = CRM_EX_CANTCREAT;
	                break;
	            default:
	                exit_code = CRM_EX_ERROR;
	                break;
	        }
	
	        /* Use _exit() because exit() could affect the parent adversely */
	        _exit(exit_code);
	    }
	    return exit_rc;
	}