Autorename disks using UUID for matching

HISTORY

@@ -6,6 +6,8 @@ SnapRAID HISTORY
  * Fixes support for symlinks pointing to an empty target. Before they
    were only partially supported, and their presence could result in
    a content file not readable.
+ * Autorename disks using the matching UUID. To rename a disk you can
+   now change directly the name in the configuration file.
  * Improves the physical offset ordering for the Btrfs filesystem,
    correctly detecting files that have not a physical offset, for
    whatever reason.

Makefile.am

@@ -118,6 +118,7 @@ EXTRA_DIST = \
 	test/test-par6.conf \
 	test/test-par6-hole.conf \
 	test/test-par6-noaccess.conf \
+	test/test-par6-rename.conf \
 	snapraid.conf.example \
 	configure.windows-x86 configure.windows-x64 snapraid.conf.example.windows \
 	acinclude.m4 \
@@ -185,6 +186,7 @@ endif
 CONF = $(srcdir)/test/test-par6.conf
 HOLE = $(srcdir)/test/test-par6-hole.conf
 NOACCESS = $(srcdir)/test/test-par6-noaccess.conf
+RENAME = $(srcdir)/test/test-par6-rename.conf
 PAR1 = $(srcdir)/test/test-par1.conf
 PAR2 = $(srcdir)/test/test-par2.conf
 PAR3 = $(srcdir)/test/test-par3.conf
@@ -425,6 +427,9 @@ endif
 	echo --- Fix with unaccessible parity and disk
 	$(FAILENV) ./snapraid$(EXEEXT) $(CHECKFLAGS) -c $(NOACCESS) fix --test-expect-failure
 	$(TESTENV) ./snapraid$(EXEEXT) $(CHECKFLAGS) -c $(NOACCESS) fix --force-device --test-expect-recoverable -l test.log
+	echo -- Rename a disk
+	$(FAILENV) ./snapraid$(EXEEXT) $(CHECKFLAGS) -c $(RENAME) --test-match-first-uuid sync
+	$(TESTENV) ./snapraid$(EXEEXT) $(CHECKFLAGS) -c $(CONF) --test-match-first-uuid sync
 #### SCRUB ####
 	echo --- Scrub some times
 	$(TESTENV) ./snapraid$(EXEEXT) $(CHECKFLAGS) -c $(CONF) --test-force-scrub-at 100 scrub

cmdline/snapraid.c

@@ -247,6 +247,7 @@ void config(char* conf, size_t conf_size, const char* argv0)
 #define OPT_TEST_EXPECT_NEED_SYNC 285
 #define OPT_NO_WARNINGS 286
 #define OPT_TEST_FAKE_UUID 287
+#define OPT_TEST_MATCH_FIRST_UUID 288
 
 #if HAVE_GETOPT_LONG
 struct option long_options[] = {
@@ -368,6 +369,9 @@ struct option long_options[] = {
 	/* Fake UUID */
 	{ "test-fake-uuid", 0, 0, OPT_TEST_FAKE_UUID },
 
+	/* Match first UUID */
+	{ "test-match-first-uuid", 0, 0, OPT_TEST_MATCH_FIRST_UUID },
+
 	{ 0, 0, 0, 0 }
 };
 #endif
@@ -740,6 +744,9 @@ int main(int argc, char* argv[])
 		case OPT_TEST_FAKE_UUID :
 			opt.fake_uuid = 2;
 			break;
+		case OPT_TEST_MATCH_FIRST_UUID :
+			opt.match_first_uuid = 1;
+			break;
 		default :
 			/* LCOV_EXCL_START */
 			log_fatal("Unknown option '%c'\n", (char)c);

cmdline/state.c

@@ -1155,7 +1155,7 @@ void state_config(struct snapraid_state* state, const char* path, const char* co
 /**
  * Find a disk by name.
  */
-static struct snapraid_disk* find_disk(struct snapraid_state* state, const char* name)
+static struct snapraid_disk* find_disk_by_name(struct snapraid_state* state, const char* name)
 {
 	tommy_node* i;
 
@@ -1179,6 +1179,39 @@ static struct snapraid_disk* find_disk(struct snapraid_state* state, const char*
 	return 0;
 }
 
+/**
+ * Find a disk by UUID.
+ */
+static struct snapraid_disk* find_disk_by_uuid(struct snapraid_state* state, const char* uuid)
+{
+	tommy_node* i;
+	struct snapraid_disk* found = 0;
+
+	/* special test case to find the first macthing UUID */
+	/* when testing UUID are all equal or not supported */
+	/* and we should handle this case specifically */
+	if (state->opt.match_first_uuid)
+		return state->disklist->data;
+
+	/* LCOV_EXCL_START */
+	/* never find an empty uuid */
+	if (!*uuid)
+		return 0;
+
+	for (i = state->disklist; i != 0; i = i->next) {
+		struct snapraid_disk* disk = i->data;
+		if (strcmp(disk->uuid, uuid) == 0) {
+			/* never match duplicate UUID */
+			if (found)
+				return 0;
+			found = disk;
+		}
+	}
+
+	return found;
+	/* LCOV_EXCL_STOP */
+}
+
 /**
  * Update the disk mapping if required.
  */
@@ -1198,7 +1231,7 @@ static void state_map(struct snapraid_state* state)
 		struct snapraid_map* map = i->data;
 		struct snapraid_disk* disk;
 
-		disk = find_disk(state, map->name);
+		disk = find_disk_by_name(state, map->name);
 
 		/* go to the next mapping before removing */
 		i = i->next;
@@ -1270,7 +1303,7 @@ static void state_map(struct snapraid_state* state)
 			struct snapraid_map* map = i->data;
 			struct snapraid_disk* disk;
 
-			disk = find_disk(state, map->name);
+			disk = find_disk_by_name(state, map->name);
 			if (disk == 0) {
 				/* LCOV_EXCL_START */
 				log_fatal("Internal inconsistency for mapping '%s'\n", map->name);
@@ -1398,7 +1431,7 @@ void state_refresh(struct snapraid_state* state)
 		uint64_t free_space;
 		int ret;
 
-		disk = find_disk(state, map->name);
+		disk = find_disk_by_name(state, map->name);
 		if (disk == 0) {
 			/* LCOV_EXCL_START */
 			log_fatal("Internal inconsistency for mapping '%s'\n", map->name);
@@ -2375,21 +2408,31 @@ static void state_read_content(struct snapraid_state* state, const char* path, S
 				/* LCOV_EXCL_STOP */
 			}
 
-			map = map_alloc(buffer, v_pos, v_total_blocks, v_free_blocks, uuid);
-
-			tommy_list_insert_tail(&state->maplist, &map->node, map);
-
 			/* find the disk */
-			disk = find_disk(state, buffer);
+			disk = find_disk_by_name(state, buffer);
+			if (!disk) {
+				/* search by UUID if renamed */
+				disk = find_disk_by_uuid(state, uuid);
+				if (disk) {
+					log_fatal("WARNING! Renaming disk '%s' to '%s'\n", buffer, disk->name);
+
+					/* write the new state with the new name */
+					state->need_write = 1;
+				}
+			}
 			if (!disk) {
 				/* LCOV_EXCL_START */
 				decoding_error(path, f);
-				log_fatal("Disk named '%s' not present in the configuration file!\n", buffer);
+				log_fatal("Disk '%s' with uuid '%s' not present in the configuration file!\n", buffer, uuid);
 				log_fatal("If you have removed it from the configuration file, please restore it\n");
 				exit(EXIT_FAILURE);
 				/* LCOV_EXCL_STOP */
 			}
 
+			map = map_alloc(disk->name, v_pos, v_total_blocks, v_free_blocks, uuid);
+
+			tommy_list_insert_tail(&state->maplist, &map->node, map);
+
 			/* insert in the mapping vector */
 			tommy_array_grow(&disk_mapping, mapping_max + 1);
 			tommy_array_set(&disk_mapping, mapping_max, disk);
@@ -2638,7 +2681,7 @@ static void* state_write_thread(void* arg)
 		struct snapraid_disk* disk;
 
 		/* find the disk for this mapping */
-		disk = find_disk(state, map->name);
+		disk = find_disk_by_name(state, map->name);
 		if (!disk) {
 			/* LCOV_EXCL_START */
 			log_fatal("Internal inconsistency for unmapped disk '%s'\n", map->name);
@@ -3072,7 +3115,7 @@ static void state_write_content(struct snapraid_state* state, uint32_t* out_crc)
 		struct snapraid_disk* disk;
 
 		/* find the disk for this mapping */
-		disk = find_disk(state, map->name);
+		disk = find_disk_by_name(state, map->name);
 		if (!disk) {
 			/* LCOV_EXCL_START */
 			log_fatal("Internal inconsistency for unmapped disk '%s'\n", map->name);
@@ -3982,7 +4025,7 @@ void generate_configuration(const char* path)
 		printf("# Set the correct dir for disk '%s'\n", map->name);
 		if (map->uuid[0])
 			printf("# Disk '%s' is the one with id '%s'\n", map->name, map->uuid);
-		disk = find_disk(&state, map->name);
+		disk = find_disk_by_name(&state, map->name);
 		if (disk && disk->filelist) {
 			struct snapraid_file* file = disk->filelist->data;
 			if (file) {

cmdline/state.h

@@ -106,6 +106,7 @@ struct snapraid_option {
 	int no_warnings; /**< Remove some warning messages. */
 	int expected_missing; /**< If missing files are expected and should not be reported. */
 	int fake_uuid; /**< Set fakes UUID for testing. */
+	int match_first_uuid; /**< Force the matching of the first UUID. */
 };
 
 /**

test/test-par6-rename.conf

@@ -0,0 +1,24 @@
+blocksize 1
+parity bench/parity
+2-parity bench/2-parity
+3-parity bench/3-parity
+4-parity bench/4-parity
+5-parity bench/5-parity
+6-parity bench/6-parity
+content bench/content
+content bench/1-content
+content bench/2-content
+content bench/3-content
+content bench/4-content
+content bench/5-content
+content bench/6-content
+disk disk1-rename bench/disk1/
+disk disk2 bench/disk2/
+disk disk3 bench/disk3/
+disk disk4 bench/disk4/
+disk disk5 bench/disk5/
+disk disk6 bench/disk6/
+include *.hidden
+exclude *.unrecoverable
+
+