From: Karel Zak <kzak@redhat.com>
Date: Tue, 11 Dec 2012 11:56:27 +0000 (+0100)
Subject: libfdisk: split label and label operations
X-Git-Tag: v2.23-rc1~157
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0c5d095e46306ed4d6009f56e0339857d733d72e;p=thirdparty%2Futil-linux.git

libfdisk: split label and label operations

 Changes:

 - fdisk_label is a private label driver struct
 - generic header of the fdisk_label points to fdisk_label_operations
 - the private fdisk_label stuff is always allocated for all drivers
   during fdisk_context initialization

 - context->labels[] contains pointers to all supported labels (drivers)
 - context->label is a pointer to the currently used label

 This change allows to:

 - store label specific global settings (e.g. dos compatible mode,
   display units, ...) independently on the current label

 - add label specific function to the API

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

diff --git a/fdisks/fdiskaixlabel.c b/fdisks/fdiskaixlabel.c
index d836363c9a..d5872243be 100644
--- a/fdisks/fdiskaixlabel.c
+++ b/fdisks/fdiskaixlabel.c
@@ -17,6 +17,14 @@
 static	int     other_endian = 0;
 static  short	volumes=1;
 
+/*
+ * in-memory fdisk AIX stuff
+ */
+struct fdisk_aix_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+
 /*
  * only dealing with free blocks here
  */
@@ -80,13 +88,31 @@ static int aix_add_partition(
 	return -ENOSYS;
 }
 
-const struct fdisk_label aix_label =
+static const struct fdisk_label_operations aix_operations =
 {
-	.name = "aix",
-	.probe = aix_probe_label,
-	.write = NULL,
-	.verify = NULL,
-	.create = NULL,
-	.part_add = aix_add_partition,
-	.part_delete = NULL,
+	.probe		= aix_probe_label,
+	.part_add	= aix_add_partition
 };
+
+
+/*
+ * allocates AIX label driver
+ */
+struct fdisk_label *fdisk_new_aix_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_aix_label *aix;
+
+	assert(cxt);
+
+	aix = calloc(1, sizeof(*aix));
+	if (!aix)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) aix;
+	lb->name = "aix";
+	lb->op = &aix_operations;
+
+	return lb;
+}
diff --git a/fdisks/fdiskbsdlabel.c b/fdisks/fdiskbsdlabel.c
index c3b76a3377..ef2047a0a5 100644
--- a/fdisks/fdiskbsdlabel.c
+++ b/fdisks/fdiskbsdlabel.c
@@ -62,6 +62,14 @@
 #include "fdiskbsdlabel.h"
 #include "fdiskdoslabel.h"
 
+/*
+ * in-memory fdisk BSD stuff
+ */
+struct fdisk_bsd_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+
 static int xbsd_delete_part (struct fdisk_context *cxt, int partnum);
 static void xbsd_edit_disklabel (void);
 static void xbsd_write_bootstrap (struct fdisk_context *cxt);
@@ -879,18 +887,38 @@ static int xbsd_set_parttype(struct fdisk_context *cxt, int partnum,
 	return 0;
 }
 
-const struct fdisk_label bsd_label =
+static const struct fdisk_label_operations bsd_operations =
 {
-	.name = "bsd",
-	.parttypes = xbsd_fstypes,
-	.nparttypes = ARRAY_SIZE(xbsd_fstypes),
-
-	.probe = osf_probe_label,
-	.write = xbsd_write_disklabel,
-	.verify = NULL,
-	.create = xbsd_create_disklabel,
-	.part_add = xbsd_add_part,
-	.part_delete = xbsd_delete_part,
-	.part_get_type = xbsd_get_parttype,
-	.part_set_type = xbsd_set_parttype,
+	.probe		= osf_probe_label,
+	.write		= xbsd_write_disklabel,
+	.create		= xbsd_create_disklabel,
+	.part_add	= xbsd_add_part,
+	.part_delete	= xbsd_delete_part,
+	.part_get_type	= xbsd_get_parttype,
+	.part_set_type	= xbsd_set_parttype
 };
+
+
+/*
+ * allocates BSD label driver
+ */
+struct fdisk_label *fdisk_new_bsd_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_bsd_label *bsd;
+
+	assert(cxt);
+
+	bsd = calloc(1, sizeof(*bsd));
+	if (!bsd)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) bsd;
+	lb->name = "bsd";
+	lb->op = &bsd_operations;
+	lb->parttypes = xbsd_fstypes;
+	lb->nparttypes = ARRAY_SIZE(xbsd_fstypes);
+
+	return lb;
+}
diff --git a/fdisks/fdiskdoslabel.c b/fdisks/fdiskdoslabel.c
index 45343c8383..74d24cdea2 100644
--- a/fdisks/fdiskdoslabel.c
+++ b/fdisks/fdiskdoslabel.c
@@ -13,6 +13,17 @@
 #include "fdisk.h"
 #include "fdiskdoslabel.h"
 
+
+/*
+ * in-memory fdisk GPT stuff
+ */
+struct fdisk_dos_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+/*
+ * Partition types
+ */
 static struct fdisk_parttype dos_parttypes[] = {
 	#include "dos_part_types.h"
 };
@@ -934,19 +945,39 @@ static int dos_set_parttype(struct fdisk_context *cxt, int partnum,
 	return 0;
 }
 
-const struct fdisk_label dos_label =
+static const struct fdisk_label_operations dos_operations =
 {
-	.name = "dos",
-	.parttypes = dos_parttypes,
-	.nparttypes = ARRAY_SIZE(dos_parttypes),
-
-	.probe = dos_probe_label,
-	.write = dos_write_disklabel,
-	.verify = dos_verify_disklabel,
-	.create = dos_create_disklabel,
-	.part_add = dos_add_partition,
-	.part_delete = dos_delete_partition,
-	.part_get_type = dos_get_parttype,
-	.part_set_type = dos_set_parttype,
+	.probe		= dos_probe_label,
+	.write		= dos_write_disklabel,
+	.verify		= dos_verify_disklabel,
+	.create		= dos_create_disklabel,
+	.part_add	= dos_add_partition,
+	.part_delete	= dos_delete_partition,
+	.part_get_type	= dos_get_parttype,
+	.part_set_type	= dos_set_parttype,
 	.reset_alignment = dos_reset_alignment,
 };
+
+/*
+ * allocates DOS in-memory stuff
+ */
+struct fdisk_label *fdisk_new_dos_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_dos_label *dos;
+
+	assert(cxt);
+
+	dos = calloc(1, sizeof(*dos));
+	if (!dos)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) dos;
+	lb->name = "dos";
+	lb->op = &dos_operations;
+	lb->parttypes = dos_parttypes;
+	lb->nparttypes = ARRAY_SIZE(dos_parttypes);
+
+	return lb;
+}
diff --git a/fdisks/fdiskmaclabel.c b/fdisks/fdiskmaclabel.c
index de3a8ccbcb..f15b802cce 100644
--- a/fdisks/fdiskmaclabel.c
+++ b/fdisks/fdiskmaclabel.c
@@ -16,6 +16,13 @@
 
 #define MAC_BITMASK 0xffff0000
 
+/*
+ * in-memory fdisk mac stuff
+ */
+struct fdisk_mac_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
 
 static	int     other_endian = 0;
 static  short	volumes=1;
@@ -98,13 +105,31 @@ static int mac_add_partition(
 	return -ENOSYS;
 }
 
-const struct fdisk_label mac_label =
+static const struct fdisk_label_operations mac_operations =
 {
-	.name = "mac",
-	.probe = mac_probe_label,
-	.write = NULL,
-	.verify = NULL,
-	.create = NULL,
-	.part_add = mac_add_partition,
-	.part_delete = NULL,
+	.probe		= mac_probe_label,
+	.part_add	= mac_add_partition
 };
+
+
+/*
+ * allocates MAC label driver
+ */
+struct fdisk_label *fdisk_new_mac_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_mac_label *mac;
+
+	assert(cxt);
+
+	mac = calloc(1, sizeof(*mac));
+	if (!mac)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) mac;
+	lb->name = "mac";
+	lb->op = &mac_operations;
+
+	return lb;
+}
diff --git a/fdisks/fdisksgilabel.c b/fdisks/fdisksgilabel.c
index cf20445e41..c58e7263be 100644
--- a/fdisks/fdisksgilabel.c
+++ b/fdisks/fdisksgilabel.c
@@ -35,6 +35,15 @@
 #include "fdisksgilabel.h"
 #include "fdiskdoslabel.h"
 
+
+/*
+ * in-memory fdisk SGI stuff
+ */
+struct fdisk_sgi_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+
 static	int     other_endian = 0;
 static	int     debug = 0;
 static  short volumes=1;
@@ -929,18 +938,38 @@ static int sgi_set_parttype(struct fdisk_context *cxt, int i,
 	return 0;
 }
 
-const struct fdisk_label sgi_label =
+static const struct fdisk_label_operations sgi_operations =
 {
-	.name = "sgi",
-	.parttypes = sgi_parttypes,
-	.nparttypes = ARRAY_SIZE(sgi_parttypes),
-
-	.probe = sgi_probe_label,
-	.write = sgi_write_disklabel,
-	.verify = sgi_verify_disklabel,
-	.create = sgi_create_disklabel,
-	.part_add = sgi_add_partition,
-	.part_delete = sgi_delete_partition,
-	.part_get_type = sgi_get_parttype,
-	.part_set_type = sgi_set_parttype,
+	.probe		= sgi_probe_label,
+	.write		= sgi_write_disklabel,
+	.verify		= sgi_verify_disklabel,
+	.create		= sgi_create_disklabel,
+	.part_add	= sgi_add_partition,
+	.part_delete	= sgi_delete_partition,
+	.part_get_type	= sgi_get_parttype,
+	.part_set_type	= sgi_set_parttype
 };
+
+/*
+ * allocates SGI label driver
+ */
+struct fdisk_label *fdisk_new_sgi_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_sgi_label *sgi;
+
+	assert(cxt);
+
+	sgi = calloc(1, sizeof(*sgi));
+	if (!sgi)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) sgi;
+	lb->name = "sgi";
+	lb->op = &sgi_operations;
+	lb->parttypes = sgi_parttypes;
+	lb->nparttypes = ARRAY_SIZE(sgi_parttypes);
+
+	return lb;
+}
diff --git a/fdisks/fdisksunlabel.c b/fdisks/fdisksunlabel.c
index cb22ffcec1..77d6601682 100644
--- a/fdisks/fdisksunlabel.c
+++ b/fdisks/fdisksunlabel.c
@@ -28,6 +28,14 @@
 
 static int     other_endian = 0;
 
+/*
+ * in-memory fdisk SUN stuff
+ */
+struct fdisk_sun_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+
 static struct fdisk_parttype sun_parttypes[] = {
 	{SUN_TAG_UNASSIGNED, N_("Unassigned")},
 	{SUN_TAG_BOOT, N_("Boot")},
@@ -684,19 +692,39 @@ static int sun_reset_alignment(struct fdisk_context *cxt)
 	return 0;
 }
 
-const struct fdisk_label sun_label =
+const struct fdisk_label_operations sun_operations =
 {
-	.name = "sun",
-	.parttypes = sun_parttypes,
-	.nparttypes = ARRAY_SIZE(sun_parttypes),
-
-	.probe = sun_probe_label,
-	.write = sun_write_disklabel,
-	.verify = sun_verify_disklabel,
-	.create = sun_create_disklabel,
-	.part_add = sun_add_partition,
-	.part_delete = sun_delete_partition,
-	.part_get_type = sun_get_parttype,
-	.part_set_type = sun_set_parttype,
-	.reset_alignment = sun_reset_alignment,
+	.probe		= sun_probe_label,
+	.write		= sun_write_disklabel,
+	.verify		= sun_verify_disklabel,
+	.create		= sun_create_disklabel,
+	.part_add	= sun_add_partition,
+	.part_delete	= sun_delete_partition,
+	.part_get_type	= sun_get_parttype,
+	.part_set_type	= sun_set_parttype,
+	.reset_alignment = sun_reset_alignment
 };
+
+/*
+ * allocates SUN label driver
+ */
+struct fdisk_label *fdisk_new_sun_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_sun_label *sun;
+
+	assert(cxt);
+
+	sun = calloc(1, sizeof(*sun));
+	if (!sun)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) sun;
+	lb->name = "sun";
+	lb->op = &sun_operations;
+	lb->parttypes = sun_parttypes;
+	lb->nparttypes = ARRAY_SIZE(sun_parttypes);
+
+	return lb;
+}
diff --git a/fdisks/gpt.c b/fdisks/gpt.c
index 0784d639a5..4f70f962d0 100644
--- a/fdisks/gpt.c
+++ b/fdisks/gpt.c
@@ -45,6 +45,14 @@
 #include "strutils.h"
 #include "all-io.h"
 
+/*
+ * in-memory fdisk GPT stuff
+ */
+struct fdisk_gpt_label {
+	struct fdisk_label	head;		/* generic part */
+};
+
+
 #define GPT_HEADER_SIGNATURE 0x5452415020494645LL /* EFI PART */
 #define GPT_HEADER_REVISION_V1_02 0x00010200
 #define GPT_HEADER_REVISION_V1_00 0x00010000
@@ -1655,18 +1663,38 @@ static int gpt_set_partition_type(struct fdisk_context *cxt, int i,
 	return 0;
 }
 
-const struct fdisk_label gpt_label =
+static const struct fdisk_label_operations gpt_operations =
 {
-	.name = "gpt",
-	.parttypes = gpt_parttypes,
-	.nparttypes = ARRAY_SIZE(gpt_parttypes),
-
-	.probe = gpt_probe_label,
-	.write = gpt_write_disklabel,
-	.verify = gpt_verify_disklabel,
-	.create = gpt_create_disklabel,
-	.part_add = gpt_add_partition,
-	.part_delete = gpt_delete_partition,
-	.part_get_type = gpt_get_partition_type,
-	.part_set_type = gpt_set_partition_type
+	.probe		= gpt_probe_label,
+	.write		= gpt_write_disklabel,
+	.verify		= gpt_verify_disklabel,
+	.create		= gpt_create_disklabel,
+	.part_add	= gpt_add_partition,
+	.part_delete	= gpt_delete_partition,
+	.part_get_type	= gpt_get_partition_type,
+	.part_set_type	= gpt_set_partition_type
 };
+
+/*
+ * allocates GPT in-memory stuff
+ */
+struct fdisk_label *fdisk_new_gpt_label(struct fdisk_context *cxt)
+{
+	struct fdisk_label *lb;
+	struct fdisk_gpt_label *gpt;
+
+	assert(cxt);
+
+	gpt = calloc(1, sizeof(*gpt));
+	if (!gpt)
+		return NULL;
+
+	/* initialize generic part of the driver */
+	lb = (struct fdisk_label *) gpt;
+	lb->name = "gpt";
+	lb->op = &gpt_operations;
+	lb->parttypes = gpt_parttypes;
+	lb->nparttypes = ARRAY_SIZE(gpt_parttypes);
+
+	return lb;
+}
diff --git a/libfdisk/src/alignment.c b/libfdisk/src/alignment.c
index 25c0c6467b..1ef5796a45 100644
--- a/libfdisk/src/alignment.c
+++ b/libfdisk/src/alignment.c
@@ -368,8 +368,8 @@ int fdisk_reset_alignment(struct fdisk_context *cxt)
 	cxt->first_lba = fdisk_topology_get_first_lba(cxt);
 
 	/* overwrite default by label stuff */
-	if (cxt->label && cxt->label->reset_alignment)
-		rc = cxt->label->reset_alignment(cxt);
+	if (cxt->label && cxt->label->op->reset_alignment)
+		rc = cxt->label->op->reset_alignment(cxt);
 
 	DBG(LABEL, dbgprint("%s alignment reseted to: "
 			    "first LBA=%ju, grain=%lu [rc=%d]",
diff --git a/libfdisk/src/context.c b/libfdisk/src/context.c
index 302020590d..83420a9779 100644
--- a/libfdisk/src/context.c
+++ b/libfdisk/src/context.c
@@ -1,8 +1,54 @@
 
 #include "fdiskP.h"
 
+static struct fdisk_context *fdisk_new_context(void)
+{
+	struct fdisk_context *cxt;
+	size_t i;
+
+	cxt = calloc(1, sizeof(*cxt));
+	if (!cxt)
+		return NULL;
+
+	/*
+	 * Allocate label specific structs.
+	 *
+	 * This is necessary (for example) to store label specific
+	 * context setting.
+	 */
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_gpt_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_dos_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_aix_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_bsd_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_mac_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_sgi_label(cxt);
+	cxt->labels[ cxt->nlabels++ ] = fdisk_new_sun_label(cxt);
+
+	DBG(CONTEXT, dbgprint("supported labels:"));
+	for (i = 0; i < cxt->nlabels; i++) {
+		DBG(CONTEXT, dbgprint(" %s", cxt->labels[i]->name));
+		cxt->labels[i]->cxt = cxt;
+	}
+
+	return cxt;
+}
+
+struct fdisk_label *fdisk_context_get_label(struct fdisk_context *cxt, const char *name)
+{
+	size_t i;
+
+	assert(cxt);
+
+	for (i = 0; i < cxt->nlabels; i++)
+		if (strcmp(cxt->labels[i]->name, name) == 0)
+			return cxt->labels[i];
+
+	DBG(LABEL, dbgprint("failed to found %s label driver\n", name));
+	return NULL;
+}
+
 /**
- * fdisk_new_context:
+ * fdisk_new_context_from_filename:
  * @fname: path to the device to be handled
  * @readonly: how to open the device
  *
@@ -25,7 +71,7 @@ struct fdisk_context *fdisk_new_context_from_filename(const char *fname, int rea
 		readonly = 1;
 	}
 
-	cxt = calloc(1, sizeof(*cxt));
+	cxt = fdisk_new_context();
 	if (!cxt)
 		goto fail;
 
@@ -67,12 +113,26 @@ fail:
  */
 void fdisk_free_context(struct fdisk_context *cxt)
 {
+	int i;
+
 	if (!cxt)
 		return;
 
 	DBG(CONTEXT, dbgprint("freeing context %p for %s", cxt, cxt->dev_path));
-	close(cxt->dev_fd);
+	if (cxt->dev_fd > -1)
+		close(cxt->dev_fd);
 	free(cxt->dev_path);
 	free(cxt->firstsector);
+
+	/* deallocate label's private stuff */
+	for (i = 0; i < cxt->nlabels; i++) {
+		if (!cxt->labels[i])
+			continue;
+		if (cxt->labels[i]->op->free)
+			cxt->labels[i]->op->free(cxt->labels[i]);
+		else
+			free(cxt->labels[i]);
+	}
+
 	free(cxt);
 }
diff --git a/libfdisk/src/fdiskP.h b/libfdisk/src/fdiskP.h
index eac127ee6c..01dd71f514 100644
--- a/libfdisk/src/fdiskP.h
+++ b/libfdisk/src/fdiskP.h
@@ -118,6 +118,56 @@ struct fdisk_geometry {
 	sector_t cylinders;
 };
 
+/*
+ * Label specific operations
+ */
+struct fdisk_label_operations {
+	/* probe disk label */
+	int (*probe)(struct fdisk_context *cxt);
+	/* write in-memory changes to disk */
+	int (*write)(struct fdisk_context *cxt);
+	/* verify the partition table */
+	int (*verify)(struct fdisk_context *cxt);
+	/* create new disk label */
+	int (*create)(struct fdisk_context *cxt);
+	/* new partition */
+	int (*part_add)(struct fdisk_context *cxt, int partnum, struct fdisk_parttype *t);
+	/* delete partition */
+	int (*part_delete)(struct fdisk_context *cxt, int partnum);
+	/* get partition type */
+	struct fdisk_parttype *(*part_get_type)(struct fdisk_context *cxt, int partnum);
+	/* set partition type */
+	int (*part_set_type)(struct fdisk_context *cxt, int partnum, struct fdisk_parttype *t);
+	/* refresh alignment setting */
+	int (*reset_alignment)(struct fdisk_context *cxt);
+
+	/* free in-memory label stuff */
+	void (*free)(struct fdisk_label *lb);
+};
+
+/*
+ * Generic label
+ */
+struct fdisk_label {
+	const char *name;
+
+	struct fdisk_parttype	*parttypes;
+	size_t			nparttypes;	/* number of items in parttypes[] */
+
+	const struct fdisk_label_operations *op;
+
+	struct fdisk_context	*cxt;
+};
+
+/* label allocators */
+extern struct fdisk_label *fdisk_new_gpt_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_dos_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_aix_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_bsd_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_mac_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_sgi_label(struct fdisk_context *cxt);
+extern struct fdisk_label *fdisk_new_sun_label(struct fdisk_context *cxt);
+
 struct fdisk_context {
 	int dev_fd;         /* device descriptor */
 	char *dev_path;     /* device path */
@@ -141,39 +191,14 @@ struct fdisk_context {
 	sector_t total_sectors; /* in logical sectors */
 	struct fdisk_geometry geom;
 
-	/* label operations and description */
-	const struct fdisk_label *label;
-};
+	struct fdisk_label *label;	/* current label, pointer to labels[] */
 
-/*
- * Label specific operations
- */
-struct fdisk_label {
-	const char *name;
+	size_t nlabels;			/* number of initialized label drivers */
+	struct fdisk_label *labels[8];	/* all supported labels,
+					 * FIXME: use any enum rather than hardcoded number */
+};
 
-	/* array with partition types */
-	struct fdisk_parttype	*parttypes;
-	size_t			nparttypes;	/* number of items in parttypes[] */
 
-	/* probe disk label */
-	int (*probe)(struct fdisk_context *cxt);
-	/* write in-memory changes to disk */
-	int (*write)(struct fdisk_context *cxt);
-	/* verify the partition table */
-	int (*verify)(struct fdisk_context *cxt);
-	/* create new disk label */
-	int (*create)(struct fdisk_context *cxt);
-	/* new partition */
-	int (*part_add)(struct fdisk_context *cxt, int partnum, struct fdisk_parttype *t);
-	/* delete partition */
-	int (*part_delete)(struct fdisk_context *cxt, int partnum);
-	/* get partition type */
-	struct fdisk_parttype *(*part_get_type)(struct fdisk_context *cxt, int partnum);
-	/* set partition type */
-	int (*part_set_type)(struct fdisk_context *cxt, int partnum, struct fdisk_parttype *t);
-	/* refresh alignment setting */
-	int (*reset_alignment)(struct fdisk_context *cxt);
-};
 
 /* alignment.c */
 extern sector_t fdisk_topology_get_first_lba(struct fdisk_context *cxt);
diff --git a/libfdisk/src/label.c b/libfdisk/src/label.c
index 5d0eb3ef8a..8f99348355 100644
--- a/libfdisk/src/label.c
+++ b/libfdisk/src/label.c
@@ -1,28 +1,6 @@
 
 #include "fdiskP.h"
 
-/*
- * Label probing functions.
- */
-extern const struct fdisk_label aix_label;
-extern const struct fdisk_label dos_label;
-extern const struct fdisk_label bsd_label;
-extern const struct fdisk_label mac_label;
-extern const struct fdisk_label sun_label;
-extern const struct fdisk_label sgi_label;
-extern const struct fdisk_label gpt_label;
-
-static const struct fdisk_label *labels[] =
-{
-	&gpt_label,
-	&dos_label,
-	&sun_label,
-	&sgi_label,
-	&aix_label,
-	&bsd_label,
-	&mac_label,
-};
-
 /*
  * Don't use this function derectly, use fdisk_new_context_from_filename()
  */
@@ -32,11 +10,12 @@ int fdisk_probe_labels(struct fdisk_context *cxt)
 
 	cxt->disklabel = FDISK_DISKLABEL_ANY;
 
-	for (i = 0; i < ARRAY_SIZE(labels); i++) {
-		if (!labels[i]->probe || labels[i]->probe(cxt) != 1)
+	for (i = 0; i < cxt->nlabels; i++) {
+		if (!cxt->labels[i]->op->probe ||
+		     cxt->labels[i]->op->probe(cxt) != 1)
 			continue;
 
-		cxt->label = labels[i];
+		cxt->label = cxt->labels[i];
 
 		DBG(LABEL, dbgprint("detected a %s label", cxt->label->name));
 		return 0;
@@ -81,10 +60,10 @@ int fdisk_write_disklabel(struct fdisk_context *cxt)
 {
 	if (!cxt || !cxt->label)
 		return -EINVAL;
-	if (!cxt->label->write)
+	if (!cxt->label->op->write)
 		return -ENOSYS;
 
-	return cxt->label->write(cxt);
+	return cxt->label->op->write(cxt);
 }
 
 /**
@@ -99,10 +78,10 @@ int fdisk_verify_disklabel(struct fdisk_context *cxt)
 {
 	if (!cxt || !cxt->label)
 		return -EINVAL;
-	if (!cxt->label->verify)
+	if (!cxt->label->op->verify)
 		return -ENOSYS;
 
-	return cxt->label->verify(cxt);
+	return cxt->label->op->verify(cxt);
 }
 
 /**
@@ -120,11 +99,11 @@ int fdisk_add_partition(struct fdisk_context *cxt, int partnum,
 {
 	if (!cxt || !cxt->label)
 		return -EINVAL;
-	if (!cxt->label->part_add)
+	if (!cxt->label->op->part_add)
 		return -ENOSYS;
 
 	DBG(LABEL, dbgprint("adding new partition number %d", partnum));
-	cxt->label->part_add(cxt, partnum, t);
+	cxt->label->op->part_add(cxt, partnum, t);
 	return 0;
 }
 
@@ -141,12 +120,12 @@ int fdisk_delete_partition(struct fdisk_context *cxt, int partnum)
 {
 	if (!cxt || !cxt->label)
 		return -EINVAL;
-	if (!cxt->label->part_delete)
+	if (!cxt->label->op->part_delete)
 		return -ENOSYS;
 
 	DBG(LABEL, dbgprint("deleting %s partition number %d",
 				cxt->label->name, partnum));
-	return cxt->label->part_delete(cxt, partnum);
+	return cxt->label->op->part_delete(cxt, partnum);
 }
 
 /**
@@ -164,35 +143,24 @@ int fdisk_create_disklabel(struct fdisk_context *cxt, const char *name)
 	if (!cxt)
 		return -EINVAL;
 
-	cxt->label = NULL;
-
 	if (!name) { /* use default label creation */
 #ifdef __sparc__
-		cxt->label = &sun_label;
+		name = "sun";
 #else
-		cxt->label = &dos_label;
+		name = "dos";
 #endif
-	} else {
-		size_t i;
-
-		for (i = 0; i < ARRAY_SIZE(labels); i++) {
-			if (strcmp(name, labels[i]->name) != 0)
-				continue;
-
-			cxt->label = labels[i];
-			DBG(LABEL, dbgprint("changing to %s label\n", cxt->label->name));
-			break;
-		}
 	}
 
+	cxt->label = fdisk_context_get_label(cxt, name);
 	if (!cxt->label)
 		return -EINVAL;
-	if (!cxt->label->create)
+
+	DBG(LABEL, dbgprint("changing to %s label\n", cxt->label->name));
+	if (!cxt->label->op->create)
 		return -ENOSYS;
 
 	fdisk_reset_alignment(cxt);
-
-	return cxt->label->create(cxt);
+	return cxt->label->op->create(cxt);
 }
 
 /**
@@ -204,11 +172,11 @@ int fdisk_create_disklabel(struct fdisk_context *cxt, const char *name)
  */
 struct fdisk_parttype *fdisk_get_partition_type(struct fdisk_context *cxt, int partnum)
 {
-	if (!cxt || !cxt->label || !cxt->label->part_get_type)
+	if (!cxt || !cxt->label || !cxt->label->op->part_get_type)
 		return NULL;
 
 	DBG(LABEL, dbgprint("partition: %d: get type", partnum));
-	return cxt->label->part_get_type(cxt, partnum);
+	return cxt->label->op->part_get_type(cxt, partnum);
 }
 
 /**
@@ -222,11 +190,11 @@ struct fdisk_parttype *fdisk_get_partition_type(struct fdisk_context *cxt, int p
 int fdisk_set_partition_type(struct fdisk_context *cxt, int partnum,
 			     struct fdisk_parttype *t)
 {
-	if (!cxt || !cxt->label || !cxt->label->part_set_type)
+	if (!cxt || !cxt->label || !cxt->label->op->part_set_type)
 		return -EINVAL;
 
 	DBG(LABEL, dbgprint("partition: %d: set type", partnum));
-	return cxt->label->part_set_type(cxt, partnum, t);
+	return cxt->label->op->part_set_type(cxt, partnum, t);
 }
 
 /**
diff --git a/libfdisk/src/libfdisk.h b/libfdisk/src/libfdisk.h
index d719a5c8d3..d72a608899 100644
--- a/libfdisk/src/libfdisk.h
+++ b/libfdisk/src/libfdisk.h
@@ -26,6 +26,7 @@ extern "C" {
 #endif
 
 struct fdisk_context;
+struct fdisk_label;
 struct fdisk_parttype;
 
 /*
@@ -50,6 +51,9 @@ extern struct fdisk_context *fdisk_new_context_from_filename(
 				const char *fname, int readonly);
 extern void fdisk_free_context(struct fdisk_context *cxt);
 
+extern struct fdisk_label *fdisk_context_get_label(struct fdisk_context *cxt,
+				const char *name);
+
 /* parttype.c */
 extern struct fdisk_parttype *fdisk_get_parttype_from_code(struct fdisk_context *cxt,
                                 unsigned int code);