From: Karel Zak <kzak@redhat.com>
Date: Tue, 25 Jun 2013 12:40:34 +0000 (+0200)
Subject: libfdisk: add generic function to get disklabel ID
X-Git-Tag: v2.24-rc1~157
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=21fe3dde849c59a54641f43cbea2eafdf4d07acf;p=thirdparty%2Futil-linux.git

libfdisk: add generic function to get disklabel ID

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/fdisks/fdisk.c b/fdisks/fdisk.c
index dae7986fac..803eeeed9d 100644
--- a/fdisks/fdisk.c
+++ b/fdisks/fdisk.c
@@ -229,8 +229,9 @@ static void change_partition_type(struct fdisk_context *cxt)
 	fdisk_free_parttype(org_t);
 }
 
-static void
-list_disk_geometry(struct fdisk_context *cxt) {
+static void list_disk_geometry(struct fdisk_context *cxt)
+{
+	char *id = NULL;
 	unsigned long long bytes = cxt->total_sectors * cxt->sector_size;
 	long megabytes = bytes/1000000;
 
@@ -262,8 +263,9 @@ list_disk_geometry(struct fdisk_context *cxt) {
 		printf(_("Alignment offset: %lu bytes\n"), cxt->alignment_offset);
 	if (fdisk_dev_has_disklabel(cxt))
 		printf(_("Disk label type: %s\n"), cxt->label->name);
-	if (fdisk_is_disklabel(cxt, DOS))
-		dos_print_mbr_id(cxt);
+
+	if (fdisk_get_disklabel_id(cxt, &id) == 0 && id)
+		printf(_("Disk identifier: %s\n"), id);
 	printf("\n");
 }
 
diff --git a/fdisks/fdiskdoslabel.c b/fdisks/fdiskdoslabel.c
index 40656c4dc1..023fbbdb17 100644
--- a/fdisks/fdiskdoslabel.c
+++ b/fdisks/fdiskdoslabel.c
@@ -438,10 +438,20 @@ static void read_extended(struct fdisk_context *cxt, int ext)
 	}
 }
 
-void dos_print_mbr_id(struct fdisk_context *cxt)
+static int dos_get_disklabel_id(struct fdisk_context *cxt, char **id)
 {
-	fdisk_info(cxt, _("Disk identifier: 0x%08x"),
-			mbr_get_id(cxt->firstsector));
+	unsigned int num;
+
+	assert(cxt);
+	assert(id);
+	assert(cxt->label);
+	assert(fdisk_is_disklabel(cxt, DOS));
+
+	num = mbr_get_id(cxt->firstsector);
+	if (asprintf(id, "0x%08x", num) > 0)
+		return 0;
+
+	return -ENOMEM;
 }
 
 static int dos_create_disklabel(struct fdisk_context *cxt)
@@ -1797,6 +1807,7 @@ static const struct fdisk_label_operations dos_operations =
 	.verify		= dos_verify_disklabel,
 	.create		= dos_create_disklabel,
 	.list		= dos_list_disklabel,
+	.get_id		= dos_get_disklabel_id,
 
 	.part_add	= dos_add_partition,
 	.part_delete	= dos_delete_partition,
diff --git a/libfdisk/src/fdiskP.h b/libfdisk/src/fdiskP.h
index d20154b802..a24f2e6eff 100644
--- a/libfdisk/src/fdiskP.h
+++ b/libfdisk/src/fdiskP.h
@@ -148,6 +148,8 @@ struct fdisk_label_operations {
 	int (*create)(struct fdisk_context *cxt);
 	/* list partition table */
 	int (*list)(struct fdisk_context *cxt);
+	/* get disk label ID */
+	int (*get_id)(struct fdisk_context *cxt, char **id);
 
 	/* new partition */
 	int (*part_add)(struct fdisk_context *cxt,
diff --git a/libfdisk/src/gpt.c b/libfdisk/src/gpt.c
index 9270e2ef94..efe78a50a5 100644
--- a/libfdisk/src/gpt.c
+++ b/libfdisk/src/gpt.c
@@ -1709,7 +1709,7 @@ static int gpt_create_disklabel(struct fdisk_context *cxt)
 {
 	int rc = 0;
 	ssize_t esz = 0;
-	struct gpt_guid *uid;
+	char str[37];
 	struct fdisk_gpt_label *gpt;
 
 	assert(cxt);
@@ -1765,21 +1765,32 @@ static int gpt_create_disklabel(struct fdisk_context *cxt)
 	cxt->label->nparts_max = le32_to_cpu(gpt->pheader->npartition_entries);
 	cxt->label->nparts_cur = 0;
 
-	uid = &gpt->pheader->disk_guid;
-	fdisk_info(cxt, _("Building a new GPT disklabel "
-			    "(GUID: %08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X)\n"),
-			    uid->time_low, uid->time_mid,
-			    uid->time_hi_and_version,
-			    uid->clock_seq_hi,
-			    uid->clock_seq_low,
-			    uid->node[0], uid->node[1],
-			    uid->node[2], uid->node[3],
-			    uid->node[4], uid->node[5]);
+	guid_to_string(&gpt->pheader->disk_guid, str);
+	fdisk_info(cxt, _("Building a new GPT disklabel (GUID: %s)"), str);
 	fdisk_label_set_changed(cxt->label, 1);
 done:
 	return rc;
 }
 
+static int gpt_get_disklabel_id(struct fdisk_context *cxt, char **id)
+{
+	struct fdisk_gpt_label *gpt;
+	char str[37];
+
+	assert(cxt);
+	assert(id);
+	assert(cxt->label);
+	assert(fdisk_is_disklabel(cxt, GPT));
+
+	gpt = self_label(cxt);
+	guid_to_string(&gpt->pheader->disk_guid, str);
+
+	*id = strdup(str);
+	if (!*id)
+		return -ENOMEM;
+	return 0;
+}
+
 static struct fdisk_parttype *gpt_get_partition_type(
 		struct fdisk_context *cxt,
 		size_t i)
@@ -1973,6 +1984,8 @@ static const struct fdisk_label_operations gpt_operations =
 	.verify		= gpt_verify_disklabel,
 	.create		= gpt_create_disklabel,
 	.list		= gpt_list_disklabel,
+	.get_id		= gpt_get_disklabel_id,
+
 	.part_add	= gpt_add_partition,
 	.part_delete	= gpt_delete_partition,
 	.part_get_type	= gpt_get_partition_type,
diff --git a/libfdisk/src/label.c b/libfdisk/src/label.c
index 32af51f88e..e39a543c8f 100644
--- a/libfdisk/src/label.c
+++ b/libfdisk/src/label.c
@@ -235,6 +235,24 @@ int fdisk_create_disklabel(struct fdisk_context *cxt, const char *name)
 	return cxt->label->op->create(cxt);
 }
 
+/**
+ * fdisk_get_disklabel_id:
+ * @cxt: fdisk context
+ * @id: returns pointer to allocated string
+ *
+ * Returns 0 on success, otherwise, a corresponding error.
+ */
+int fdisk_get_disklabel_id(struct fdisk_context *cxt, char **id)
+{
+	if (!cxt || !cxt->label)
+		return -EINVAL;
+	if (!cxt->label->op->get_id)
+		return -ENOSYS;
+
+	DBG(LABEL, dbgprint("asking for %s ID", cxt->label->name));
+	return cxt->label->op->get_id(cxt, id);
+}
+
 /**
  * fdisk_get_partition_type:
  * @cxt: fdisk context
diff --git a/libfdisk/src/libfdisk.h b/libfdisk/src/libfdisk.h
index aec9ecacdd..b88756fd27 100644
--- a/libfdisk/src/libfdisk.h
+++ b/libfdisk/src/libfdisk.h
@@ -124,6 +124,8 @@ extern int fdisk_verify_disklabel(struct fdisk_context *cxt);
 extern int fdisk_create_disklabel(struct fdisk_context *cxt, const char *name);
 extern int fdisk_list_disklabel(struct fdisk_context *cxt);
 
+extern int fdisk_get_disklabel_id(struct fdisk_context *cxt, char **id);
+
 extern int fdisk_add_partition(struct fdisk_context *cxt, struct fdisk_parttype *t);
 extern int fdisk_delete_partition(struct fdisk_context *cxt, size_t partnum);