CI/GCC: Add Fedora 44, fix build errors and threadsappend

- Add Fedora 44 to CI tests
- Fix build issues from the newer compiler. These are mostly 'char *'
  to 'const char *' conversions.
- Fix threadsappend.c test waiting for the same thread TID twice.
  This caused the test to hang on F44 (but strangely not other OSs?)

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <alexander.motin@TrueNAS.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #18478

lib/libzfs/libzfs_dataset.c

@@ -708,7 +708,7 @@ zfs_open(libzfs_handle_t *hdl, const char *path, int types)
 {
 	zfs_handle_t *zhp;
 	char errbuf[ERRBUFLEN];
-	char *bookp;
+	const char *bookp;
 
 	(void) snprintf(errbuf, sizeof (errbuf),
 	    dgettext(TEXT_DOMAIN, "cannot open '%s'"), path);
@@ -3129,7 +3129,7 @@ userquota_propname_decode(const char *propname, boolean_t zoned,
     zfs_userquota_prop_t *typep, char *domain, int domainlen, uint64_t *ridp)
 {
 	zfs_userquota_prop_t type;
-	char *cp;
+	const char *cp;
 	boolean_t isuser;
 	boolean_t isgroup;
 	boolean_t isproject;
@@ -4470,12 +4470,13 @@ zfs_rename(zfs_handle_t *zhp, const char *target, renameflags_t flags)
 {
 	int ret = 0;
 	zfs_cmd_t zc = {"\0"};
-	char *delim;
 	prop_changelist_t *cl = NULL;
 	char parent[ZFS_MAX_DATASET_NAME_LEN];
 	char property[ZFS_MAXPROPLEN];
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	char errbuf[ERRBUFLEN];
+	const char *delim;
+	char *delim2;
 
 	/* if we have the same exact name, just return success */
 	if (strcmp(zhp->zfs_name, target) == 0)
@@ -4500,11 +4501,11 @@ zfs_rename(zfs_handle_t *zhp, const char *target, renameflags_t flags)
 			 */
 			(void) strlcpy(parent, zhp->zfs_name,
 			    sizeof (parent));
-			delim = strchr(parent, '@');
+			delim2 = strchr(parent, '@');
 			if (strchr(target, '@') == NULL)
-				*(++delim) = '\0';
+				*(++delim2) = '\0';
 			else
-				*delim = '\0';
+				*delim2 = '\0';
 			(void) strlcat(parent, target, sizeof (parent));
 			target = parent;
 		} else {
@@ -4525,6 +4526,7 @@ zfs_rename(zfs_handle_t *zhp, const char *target, renameflags_t flags)
 		if (!zfs_validate_name(hdl, target, zhp->zfs_type, B_TRUE))
 			return (zfs_error(hdl, EZFS_INVALIDNAME, errbuf));
 	} else {
+
 		if (flags.recursive) {
 			zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 			    "recursive rename must be a snapshot"));
@@ -4580,8 +4582,8 @@ zfs_rename(zfs_handle_t *zhp, const char *target, renameflags_t flags)
 	}
 	if (flags.recursive) {
 		char *parentname = zfs_strdup(zhp->zfs_hdl, zhp->zfs_name);
-		delim = strchr(parentname, '@');
-		*delim = '\0';
+		delim2 = strchr(parentname, '@');
+		*delim2 = '\0';
 		zfs_handle_t *zhrp = zfs_open(zhp->zfs_hdl, parentname,
 		    ZFS_TYPE_DATASET);
 		free(parentname);

lib/libzfs/libzfs_diff.c

@@ -550,8 +550,8 @@ get_snapshot_names(differ_info_t *di, const char *fromsnap,
     const char *tosnap)
 {
 	libzfs_handle_t *hdl = di->zhp->zfs_hdl;
-	char *atptrf = NULL;
-	char *atptrt = NULL;
+	const char *atptrf = NULL;
+	const char *atptrt = NULL;
 	int fdslen, fsnlen;
 	int tdslen, tsnlen;
 

lib/libzfs/libzfs_pool.c

@@ -581,7 +581,7 @@ zpool_valid_proplist(libzfs_handle_t *hdl, const char *poolname,
 		prop = zpool_name_to_prop(propname);
 		if (prop == ZPOOL_PROP_INVAL && zpool_prop_feature(propname)) {
 			int err;
-			char *fname = strchr(propname, '@') + 1;
+			const char *fname = strchr(propname, '@') + 1;
 
 			err = zfeature_lookup_name(fname, NULL);
 			if (err != 0) {

lib/libzfs/libzfs_sendrecv.c

@@ -2684,7 +2684,7 @@ zfs_send_one_cb_impl(zfs_handle_t *zhp, const char *from, int fd,
 		char bookname[ZFS_MAX_DATASET_NAME_LEN];
 		nvlist_t *redact_snaps;
 		zfs_handle_t *book_zhp;
-		char *at, *pound;
+		const char *at, *pound;
 		int dsnamelen;
 
 		pound = strchr(redactbook, '#');

lib/libzutil/os/linux/zutil_device_path_os.c

@@ -218,7 +218,8 @@ zfs_get_pci_slots_sys_path(const char *dev_name)
 	char *address2 = NULL;
 	char *path = NULL;
 	char buf[MAXPATHLEN];
-	char *tmp;
+	const char *tmp;
+	char *tmp2;
 
 	/* If they preface 'dev' with a path (like "/dev") then strip it off */
 	tmp = strrchr(dev_name, '/');
@@ -240,9 +241,9 @@ zfs_get_pci_slots_sys_path(const char *dev_name)
 	 * be "0000:01:00.0" while /sys/bus/pci/slots/0/address will be
 	 * "0000:01:00".  Just NULL terminate at the '.' so they match.
 	 */
-	tmp = strrchr(address1, '.');
-	if (tmp != NULL)
-		*tmp = '\0';
+	tmp2 = strrchr(address1, '.');
+	if (tmp2 != NULL)
+		*tmp2 = '\0';
 
 	dp = opendir("/sys/bus/pci/slots/");
 	if (dp == NULL) {
@@ -311,6 +312,7 @@ zfs_get_enclosure_sysfs_path(const char *dev_name)
 	DIR *dp = NULL;
 	struct dirent *ep;
 	char buf[MAXPATHLEN];
+	const char *tmp0;
 	char *tmp1 = NULL;
 	char *tmp2 = NULL;
 	char *tmp3 = NULL;
@@ -322,9 +324,9 @@ zfs_get_enclosure_sysfs_path(const char *dev_name)
 		return (NULL);
 
 	/* If they preface 'dev' with a path (like "/dev") then strip it off */
-	tmp1 = strrchr(dev_name, '/');
-	if (tmp1 != NULL)
-		dev_name = tmp1 + 1;    /* +1 since we want the chr after '/' */
+	tmp0 = strrchr(dev_name, '/');
+	if (tmp0 != NULL)
+		dev_name = tmp0 + 1;    /* +1 since we want the chr after '/' */
 
 	tmpsize = asprintf(&tmp1, "/sys/block/%s/device", dev_name);
 	if (tmpsize == -1 || tmp1 == NULL) {