libblkid: export info about PT magic strings

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

libblkid/src/partitions/gpt.c

@@ -26,6 +26,7 @@
 
 /* Signature - “EFI PART” */
 #define GPT_HEADER_SIGNATURE 0x5452415020494645ULL
+#define GPT_HEADER_SIGNATURE_STR "EFI PART"
 
 /* basic types */
 typedef uint16_t efi_char16_t;
@@ -326,6 +327,10 @@ static int probe_gpt_pt(blkid_probe pr,
 	if (!tab)
 		goto err;
 
+	blkid_probe_set_magic(pr, lba << 9,
+			      sizeof(GPT_HEADER_SIGNATURE_STR) - 1,
+			      (unsigned char *) GPT_HEADER_SIGNATURE_STR);
+
 	ssf = blkid_probe_get_sectorsize(pr) / 512;
 
 	fu = le64_to_cpu(h->first_usable_lba);

libblkid/src/partitions/partitions.c

@@ -530,15 +530,17 @@ int blkid_is_nested_dimension(blkid_partition par,
 	return 1;
 }
 
-static int idinfo_probe(blkid_probe pr, const struct blkid_idinfo *id)
+static int idinfo_probe(blkid_probe pr, const struct blkid_idinfo *id,
+			struct blkid_chain *chn)
 {
 	const struct blkid_idmag *mag;
+	blkid_loff_t off;
 	int rc = 1;		/* = nothing detected */
 
 	if (pr->size <= 0 || (id->minsz && id->minsz > pr->size))
 		goto nothing;	/* the device is too small */
 
-	if (blkid_probe_get_idmag(pr, id, NULL, &mag))
+	if (blkid_probe_get_idmag(pr, id, &off, &mag))
 		goto nothing;
 
 	/* final check by probing function */
@@ -549,9 +551,15 @@ static int idinfo_probe(blkid_probe pr, const struct blkid_idinfo *id)
 	        if (rc == -1) {
 			/* reset after error */
 			reset_partlist(blkid_probe_get_partlist(pr));
+			if (chn && !chn->binary)
+				blkid_probe_chain_reset_vals(pr, chn);
 			DBG(DEBUG_LOWPROBE, printf(
 				"%s probefunc failed\n", id->name));
 		}
+		if (rc == 0 && mag && chn && !chn->binary)
+			blkid_probe_set_magic(pr, off, mag->len,
+					(unsigned char *) mag->magic);
+
 		DBG(DEBUG_LOWPROBE, printf(
 			"%s: <--- (rc = %d)\n", id->name, rc));
 	}
@@ -594,7 +602,7 @@ static int partitions_probe(blkid_probe pr, struct blkid_chain *chn)
 			continue;
 
 		/* apply checks from idinfo */
-		if (idinfo_probe(pr, idinfos[i]) != 0)
+		if (idinfo_probe(pr, idinfos[i], chn) != 0)
 			continue;
 
 		name = idinfos[i]->name;
@@ -678,7 +686,7 @@ int blkid_partitions_do_subprobe(blkid_probe pr, blkid_partition parent,
 
 	blkid_probe_set_partlist(prc, ls);
 
-	rc = idinfo_probe(prc, id);
+	rc = idinfo_probe(prc, id, blkid_probe_get_chain(pr));
 
 	blkid_probe_set_partlist(prc, NULL);
 	blkid_partlist_set_parent(ls, NULL);

libblkid/src/partitions/ultrix.c

@@ -15,7 +15,9 @@
 #include "partitions.h"
 
 #define ULTRIX_MAXPARTITIONS	8
+
 #define ULTRIX_MAGIC		0x032957
+#define ULTRIX_MAGIC_STR	"\x02\x29\x57"
 
 /* sector with partition table */
 #define ULTRIX_SECTOR		((16384 - sizeof(struct ultrix_disklabel)) >> 9)
@@ -62,6 +64,10 @@ static int probe_ultrix_pt(blkid_probe pr,
 	if (!tab)
 		goto err;
 
+	blkid_probe_set_magic(pr, (ULTRIX_SECTOR << 9) + ULTRIX_OFFSET,
+			sizeof(ULTRIX_MAGIC_STR) - 1,
+			(unsigned char *) ULTRIX_MAGIC_STR);
+
 	for (i = 0; i < ULTRIX_MAXPARTITIONS; i++) {
 		if (!l->pt_part[i].pi_nblocks)
 			 blkid_partlist_increment_partno(ls);

libblkid/src/probe.c

@@ -947,11 +947,11 @@ int blkid_do_probe(blkid_probe pr)
  */
 int blkid_do_wipe(blkid_probe pr, int dryrun)
 {
-	const char *off;
+	const char *off = NULL;
 	size_t len = 0;
 	loff_t offset, l;
 	char buf[BUFSIZ];
-	int fd;
+	int fd, rc;
 	struct blkid_chain *chn;
 
 	if (!pr)
@@ -961,9 +961,22 @@ int blkid_do_wipe(blkid_probe pr, int dryrun)
 	if (!chn)
 		return -1;
 
-	if (blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL) ||
+	switch (chn->driver->id) {
-	    blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len) ||
+	case BLKID_CHAIN_SUBLKS:
-	    len == 0 || off == NULL)
+		rc = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL);
+		if (!rc)
+			rc = blkid_probe_lookup_value(pr, "SBMAGIC", NULL, &len);
+		break;
+	case BLKID_CHAIN_PARTS:
+		rc = blkid_probe_lookup_value(pr, "PTMAGIC_OFFSET", &off, NULL);
+		if (!rc)
+			rc = blkid_probe_lookup_value(pr, "PTMAGIC", NULL, &len);
+		break;
+	default:
+		return 0;
+	}
+
+	if (rc || len == 0 || off == NULL)
 		return 0;
 
 	offset = strtoll(off, NULL, 10);

misc-utils/wipefs.c

@@ -142,35 +142,51 @@ add_offset(struct wipe_desc *wp0, loff_t offset, int zap)
 static struct wipe_desc *
 get_desc_for_probe(struct wipe_desc *wp, blkid_probe pr)
 {
-	const char *off, *type, *usage, *mag;
+	const char *off, *type, *mag, *p, *usage = NULL;
 	size_t len;
+	loff_t offset;
+	int rc;
 
-	if (blkid_probe_lookup_value(pr, "TYPE", &type, NULL) == 0 &&
+	/* superblocks */
-	    blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL) == 0 &&
+	if (blkid_probe_lookup_value(pr, "TYPE", &type, NULL) == 0) {
-	    blkid_probe_lookup_value(pr, "SBMAGIC", &mag, &len) == 0 &&
+		rc = blkid_probe_lookup_value(pr, "SBMAGIC_OFFSET", &off, NULL);
-	    blkid_probe_lookup_value(pr, "USAGE", &usage, NULL) == 0) {
+		if (!rc)
+			rc = blkid_probe_lookup_value(pr, "SBMAGIC", &mag, &len);
+		if (rc)
+			return wp;
 
-		loff_t offset = strtoll(off, NULL, 10);
+	/* partitions */
-		const char *p;
+	} else if (blkid_probe_lookup_value(pr, "PTTYPE", &type, NULL) == 0) {
+		rc = blkid_probe_lookup_value(pr, "PTMAGIC_OFFSET", &off, NULL);
+		if (!rc)
+			rc = blkid_probe_lookup_value(pr, "PTMAGIC", &mag, &len);
+		if (rc)
+			return wp;
+		usage = "partition table";
+	} else
+		return wp;
 
-		wp = add_offset(wp, offset, 0);
+	offset = strtoll(off, NULL, 10);
-		if (!wp)
-			return NULL;
 
+	wp = add_offset(wp, offset, 0);
+	if (!wp)
+		return NULL;
+
+	if (usage || blkid_probe_lookup_value(pr, "USAGE", &usage, NULL) == 0)
 		wp->usage = xstrdup(usage);
-		wp->type = xstrdup(type);
-		wp->on_disk = 1;
 
-		wp->magic = xmalloc(len);
+	wp->type = xstrdup(type);
-		memcpy(wp->magic, mag, len);
+	wp->on_disk = 1;
-		wp->len = len;
 
-		if (blkid_probe_lookup_value(pr, "LABEL", &p, NULL) == 0)
+	wp->magic = xmalloc(len);
-			wp->label = xstrdup(p);
+	memcpy(wp->magic, mag, len);
+	wp->len = len;
 
-		if (blkid_probe_lookup_value(pr, "UUID", &p, NULL) == 0)
+	if (blkid_probe_lookup_value(pr, "LABEL", &p, NULL) == 0)
-			wp->uuid = xstrdup(p);
+		wp->label = xstrdup(p);
-	}
+
+	if (blkid_probe_lookup_value(pr, "UUID", &p, NULL) == 0)
+		wp->uuid = xstrdup(p);
 
 	return wp;
 }
@@ -179,7 +195,6 @@ static blkid_probe
 new_probe(const char *devname, int mode)
 {
 	blkid_probe pr;
-	int rc;
 
 	if (!devname)
 		return NULL;
@@ -198,24 +213,14 @@ new_probe(const char *devname, int mode)
 	if (!pr)
 		goto error;
 
-	blkid_probe_enable_superblocks(pr, 0);	/* enabled by default ;-( */
-
-	blkid_probe_enable_partitions(pr, 1);
-	rc = blkid_do_fullprobe(pr);
-	blkid_probe_enable_partitions(pr, 0);
-
-	if (rc == 0) {
-		const char *type = NULL;
-		blkid_probe_lookup_value(pr, "PTTYPE", &type, NULL);
-		warnx(_("WARNING: %s: appears to contain '%s' "
-				"partition table"), devname, type);
-	}
-
 	blkid_probe_enable_superblocks(pr, 1);
 	blkid_probe_set_superblocks_flags(pr, BLKID_SUBLKS_MAGIC |
 			BLKID_SUBLKS_TYPE | BLKID_SUBLKS_USAGE |
 			BLKID_SUBLKS_LABEL | BLKID_SUBLKS_UUID);
 
+	blkid_probe_enable_partitions(pr, 1);
+	blkid_probe_set_partitions_flags(pr, BLKID_PARTS_MAGIC);
+
 	return pr;
 error:
 	err(EXIT_FAILURE, _("error: %s: probing initialization failed"), devname);