diff --git a/tools/crm_diff.c b/tools/crm_diff.c
index c0d5aae050..ebb674b2d9 100644
--- a/tools/crm_diff.c
+++ b/tools/crm_diff.c
@@ -1,373 +1,375 @@
 /*
  * Copyright 2005-2022 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 <stdlib.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/param.h>
 #include <sys/types.h>
 
 #include <crm/crm.h>
 #include <crm/msg_xml.h>
 #include <crm/common/cmdline_internal.h>
 #include <crm/common/output_internal.h>
 #include <crm/common/xml.h>
 #include <crm/common/ipc.h>
 #include <crm/cib.h>
 
 #define SUMMARY "Compare two Pacemaker configurations (in XML format) to produce a custom diff-like output, " \
                 "or apply such an output as a patch"
 
 struct {
     gboolean apply;
     gboolean as_cib;
     gboolean no_version;
     gboolean raw_1;
     gboolean raw_2;
     gboolean use_stdin;
     char *xml_file_1;
     char *xml_file_2;
 } options;
 
 gboolean new_string_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error);
 gboolean original_string_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error);
 gboolean patch_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error);
 
 static GOptionEntry original_xml_entries[] = {
     { "original", 'o', 0, G_OPTION_ARG_STRING, &options.xml_file_1,
       "XML is contained in the named file",
       "FILE" },
     { "original-string", 'O', 0, G_OPTION_ARG_CALLBACK, original_string_cb,
       "XML is contained in the supplied string",
       "STRING" },
 
     { NULL }
 };
 
 static GOptionEntry operation_entries[] = {
     { "new", 'n', 0, G_OPTION_ARG_STRING, &options.xml_file_2,
       "Compare the original XML to the contents of the named file",
       "FILE" },
     { "new-string", 'N', 0, G_OPTION_ARG_CALLBACK, new_string_cb,
       "Compare the original XML with the contents of the supplied string",
       "STRING" },
     { "patch", 'p', 0, G_OPTION_ARG_CALLBACK, patch_cb,
       "Patch the original XML with the contents of the named file",
       "FILE" },
 
     { NULL }
 };
 
 static GOptionEntry addl_entries[] = {
     { "cib", 'c', 0, G_OPTION_ARG_NONE, &options.as_cib,
       "Compare/patch the inputs as a CIB (includes versions details)",
       NULL },
     { "stdin", 's', 0, G_OPTION_ARG_NONE, &options.use_stdin,
       "",
       NULL },
     { "no-version", 'u', 0, G_OPTION_ARG_NONE, &options.no_version,
       "Generate the difference without versions details",
       NULL },
 
     { NULL }
 };
 
 gboolean
 new_string_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error) {
     options.raw_2 = TRUE;
     pcmk__str_update(&options.xml_file_2, optarg);
     return TRUE;
 }
 
 gboolean
 original_string_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error) {
     options.raw_1 = TRUE;
     pcmk__str_update(&options.xml_file_1, optarg);
     return TRUE;
 }
 
 gboolean
 patch_cb(const gchar *option_name, const gchar *optarg, gpointer data, GError **error) {
     options.apply = TRUE;
     pcmk__str_update(&options.xml_file_2, optarg);
     return TRUE;
 }
 
 static void
 print_patch(xmlNode *patch)
 {
     char *buffer = dump_xml_formatted(patch);
 
     printf("%s", pcmk__s(buffer, "<null>\n"));
     free(buffer);
     fflush(stdout);
 }
 
+// \return Standard Pacemaker return code
 static int
 apply_patch(xmlNode *input, xmlNode *patch, gboolean as_cib)
 {
-    int rc;
     xmlNode *output = copy_xml(input);
+    int rc = xml_apply_patchset(output, patch, as_cib);
 
-    rc = xml_apply_patchset(output, patch, as_cib);
-    if (rc != pcmk_ok) {
-        fprintf(stderr, "Could not apply patch: %s\n", pcmk_strerror(rc));
+    rc = pcmk_legacy2rc(rc);
+    if (rc != pcmk_rc_ok) {
+        fprintf(stderr, "Could not apply patch: %s\n", pcmk_rc_str(rc));
         free_xml(output);
         return rc;
     }
 
     if (output != NULL) {
         const char *version;
         char *buffer;
 
         print_patch(output);
 
         version = crm_element_value(output, XML_ATTR_CRM_VERSION);
         buffer = calculate_xml_versioned_digest(output, FALSE, TRUE, version);
         crm_trace("Digest: %s", pcmk__s(buffer, "<null>\n"));
         free(buffer);
         free_xml(output);
     }
-    return pcmk_ok;
+    return pcmk_rc_ok;
 }
 
 static void
 log_patch_cib_versions(xmlNode *patch)
 {
     int add[] = { 0, 0, 0 };
     int del[] = { 0, 0, 0 };
 
     const char *fmt = NULL;
     const char *digest = NULL;
 
     xml_patch_versions(patch, add, del);
     fmt = crm_element_value(patch, "format");
     digest = crm_element_value(patch, XML_ATTR_DIGEST);
 
     if (add[2] != del[2] || add[1] != del[1] || add[0] != del[0]) {
         crm_info("Patch: --- %d.%d.%d %s", del[0], del[1], del[2], fmt);
         crm_info("Patch: +++ %d.%d.%d %s", add[0], add[1], add[2], digest);
     }
 }
 
 static void
 strip_patch_cib_version(xmlNode *patch, const char **vfields, size_t nvfields)
 {
     int format = 1;
 
     crm_element_value_int(patch, "format", &format);
     if (format == 2) {
         xmlNode *version_xml = find_xml_node(patch, "version", FALSE);
 
         if (version_xml) {
             free_xml(version_xml);
         }
 
     } else {
         int i = 0;
 
         const char *tags[] = {
             XML_TAG_DIFF_REMOVED,
             XML_TAG_DIFF_ADDED,
         };
 
         for (i = 0; i < PCMK__NELEM(tags); i++) {
             xmlNode *tmp = NULL;
             int lpc;
 
             tmp = find_xml_node(patch, tags[i], FALSE);
             if (tmp) {
                 for (lpc = 0; lpc < nvfields; lpc++) {
                     xml_remove_prop(tmp, vfields[lpc]);
                 }
 
                 tmp = find_xml_node(tmp, XML_TAG_CIB, FALSE);
                 if (tmp) {
                     for (lpc = 0; lpc < nvfields; lpc++) {
                         xml_remove_prop(tmp, vfields[lpc]);
                     }
                 }
             }
         }
     }
 }
 
+// \return Standard Pacemaker return code
 static int
 generate_patch(xmlNode *object_1, xmlNode *object_2, const char *xml_file_2,
                gboolean as_cib, gboolean no_version)
 {
     xmlNode *output = NULL;
 
     const char *vfields[] = {
         XML_ATTR_GENERATION_ADMIN,
         XML_ATTR_GENERATION,
         XML_ATTR_NUMUPDATES,
     };
 
     /* If we're ignoring the version, make the version information
      * identical, so it isn't detected as a change. */
     if (no_version) {
         int lpc;
 
         for (lpc = 0; lpc < PCMK__NELEM(vfields); lpc++) {
             crm_copy_xml_element(object_1, object_2, vfields[lpc]);
         }
     }
 
     xml_track_changes(object_2, NULL, object_2, FALSE);
     if(as_cib) {
         xml_calculate_significant_changes(object_1, object_2);
     } else {
         xml_calculate_changes(object_1, object_2);
     }
     crm_log_xml_debug(object_2, (xml_file_2? xml_file_2: "target"));
 
     output = xml_create_patchset(0, object_1, object_2, NULL, FALSE);
 
     xml_log_changes(LOG_INFO, __func__, object_2);
     xml_accept_changes(object_2);
 
     if (output == NULL) {
-        return pcmk_ok;
+        return pcmk_rc_ok;
     }
 
     patchset_process_digest(output, object_1, object_2, as_cib);
 
     if (as_cib) {
         log_patch_cib_versions(output);
 
     } else if (no_version) {
         strip_patch_cib_version(output, vfields, PCMK__NELEM(vfields));
     }
 
     xml_log_patchset(LOG_NOTICE, __func__, output);
     print_patch(output);
     free_xml(output);
-    return -pcmk_err_generic;
+    return pcmk_rc_error;
 }
 
 static GOptionContext *
 build_arg_context(pcmk__common_args_t *args) {
     GOptionContext *context = NULL;
 
     const char *description = "Examples:\n\n"
                               "Obtain the two different configuration files by running cibadmin on the two cluster setups to compare:\n\n"
                               "\t# cibadmin --query > cib-old.xml\n\n"
                               "\t# cibadmin --query > cib-new.xml\n\n"
                               "Calculate and save the difference between the two files:\n\n"
                               "\t# crm_diff --original cib-old.xml --new cib-new.xml > patch.xml\n\n"
                               "Apply the patch to the original file:\n\n"
                               "\t# crm_diff --original cib-old.xml --patch patch.xml > updated.xml\n\n"
                               "Apply the patch to the running cluster:\n\n"
                               "\t# cibadmin --patch -x patch.xml\n";
 
     context = pcmk__build_arg_context(args, NULL, NULL, NULL);
     g_option_context_set_description(context, description);
 
     pcmk__add_arg_group(context, "xml", "Original XML:",
                         "Show original XML options", original_xml_entries);
     pcmk__add_arg_group(context, "operation", "Operation:",
                         "Show operation options", operation_entries);
     pcmk__add_arg_group(context, "additional", "Additional Options:",
                         "Show additional options", addl_entries);
     return context;
 }
 
 int
 main(int argc, char **argv)
 {
     xmlNode *object_1 = NULL;
     xmlNode *object_2 = NULL;
 
     crm_exit_t exit_code = CRM_EX_OK;
     GError *error = NULL;
 
     pcmk__common_args_t *args = pcmk__new_common_args(SUMMARY);
     gchar **processed_args = pcmk__cmdline_preproc(argv, "nopNO");
     GOptionContext *context = build_arg_context(args);
 
-    int rc = 0;
+    int rc = pcmk_rc_ok;
 
     if (!g_option_context_parse_strv(context, &processed_args, &error)) {
         exit_code = CRM_EX_USAGE;
         goto done;
     }
 
     pcmk__cli_init_logging("crm_diff", args->verbosity);
 
     if (args->version) {
         g_strfreev(processed_args);
         pcmk__free_arg_context(context);
         /* FIXME:  When crm_diff is converted to use formatted output, this can go. */
         pcmk__cli_help('v', CRM_EX_OK);
     }
 
     if (options.apply && options.no_version) {
         fprintf(stderr, "warning: -u/--no-version ignored with -p/--patch\n");
     } else if (options.as_cib && options.no_version) {
         fprintf(stderr, "error: -u/--no-version incompatible with -c/--cib\n");
         exit_code = CRM_EX_USAGE;
         goto done;
     }
 
     if (options.raw_1) {
         object_1 = string2xml(options.xml_file_1);
 
     } else if (options.use_stdin) {
         fprintf(stderr, "Input first XML fragment:");
         object_1 = stdin2xml();
 
     } else if (options.xml_file_1 != NULL) {
         object_1 = filename2xml(options.xml_file_1);
     }
 
     if (options.raw_2) {
         object_2 = string2xml(options.xml_file_2);
 
     } else if (options.use_stdin) {
         fprintf(stderr, "Input second XML fragment:");
         object_2 = stdin2xml();
 
     } else if (options.xml_file_2 != NULL) {
         object_2 = filename2xml(options.xml_file_2);
     }
 
     if (object_1 == NULL) {
         fprintf(stderr, "Could not parse the first XML fragment\n");
         exit_code = CRM_EX_DATAERR;
         goto done;
     }
     if (object_2 == NULL) {
         fprintf(stderr, "Could not parse the second XML fragment\n");
         exit_code = CRM_EX_DATAERR;
         goto done;
     }
 
     if (options.apply) {
         rc = apply_patch(object_1, object_2, options.as_cib);
     } else {
         rc = generate_patch(object_1, object_2, options.xml_file_2, options.as_cib, options.no_version);
     }
-    exit_code = pcmk_rc2exitc(pcmk_legacy2rc(rc));
+    exit_code = pcmk_rc2exitc(rc);
 
 done:
     g_strfreev(processed_args);
     pcmk__free_arg_context(context);
     free(options.xml_file_1);
     free(options.xml_file_2);
     free_xml(object_1);
     free_xml(object_2);
 
     pcmk__output_and_clear_error(error, NULL);
     crm_exit(exit_code);
 }