From: Karel Zak <kzak@redhat.com>
Date: Fri, 22 Apr 2022 09:20:26 +0000 (+0200)
Subject: lsblk: add ID-LINK column
X-Git-Tag: v2.39-rc1~695
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ef7d50a0cc59d3b55587c8ea5fa45db45b888aee;p=thirdparty%2Futil-linux.git

lsblk: add ID-LINK column

Addresses: https://github.com/util-linux/util-linux/issues/1658
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/misc-utils/lsblk-properties.c b/misc-utils/lsblk-properties.c
index 268ea99c6d..abc0595ff9 100644
--- a/misc-utils/lsblk-properties.c
+++ b/misc-utils/lsblk-properties.c
@@ -36,6 +36,7 @@ void lsblk_device_free_properties(struct lsblk_devprop *p)
 	free(p->serial);
 	free(p->model);
 	free(p->partflags);
+	free(p->byid);
 
 	free(p->mode);
 	free(p->owner);
@@ -51,11 +52,17 @@ static struct lsblk_devprop *get_properties_by_udev(struct lsblk_device *dev
 	return NULL;
 }
 #else
+
+#define LSBLK_UDEV_BYID_PREFIX "/dev/disk/by-id/"
+#define LSBLK_UDEV_BYID_PREFIXSZ (sizeof(LSBLK_UDEV_BYID_PREFIX) - 1)
+
 static struct lsblk_devprop *get_properties_by_udev(struct lsblk_device *ld)
 {
 	struct udev_device *dev;
+	struct udev_list_entry *le;
 	const char *data;
 	struct lsblk_devprop *prop;
+	size_t len;
 
 	if (ld->udev_requested)
 		return ld->properties;
@@ -129,6 +136,25 @@ static struct lsblk_devprop *get_properties_by_udev(struct lsblk_device *ld)
 		normalize_whitespace((unsigned char *) prop->model);
 	}
 
+	/* select the shortest udev by-id symlink */
+	len = 0;
+	udev_list_entry_foreach(le, udev_device_get_devlinks_list_entry(dev)) {
+		const char *name = udev_list_entry_get_name(le);
+		size_t sz;
+
+		if (!name || !startswith(name,  LSBLK_UDEV_BYID_PREFIX))
+			continue;
+		name += LSBLK_UDEV_BYID_PREFIXSZ;
+		if (!*name)
+			continue;
+		sz = strlen(name);
+		if (!len || sz < len) {
+			len = sz;
+			free(prop->byid);
+			prop->byid = xstrdup(name);
+		}
+	}
+
 	udev_device_unref(dev);
 done:
 	ld->udev_requested = 1;
diff --git a/misc-utils/lsblk.c b/misc-utils/lsblk.c
index ab4c42179b..ea3837fda7 100644
--- a/misc-utils/lsblk.c
+++ b/misc-utils/lsblk.c
@@ -66,6 +66,7 @@ static int column_id_to_number(int id);
 /* column IDs */
 enum {
 	COL_ALIOFF = 0,
+	COL_BYID,
 	COL_DALIGN,
 	COL_DAX,
 	COL_DGRAN,
@@ -163,6 +164,7 @@ struct colinfo {
 /* columns descriptions */
 static struct colinfo infos[] = {
 	[COL_ALIOFF] = { "ALIGNMENT", 6, SCOLS_FL_RIGHT, N_("alignment offset"), COLTYPE_NUM },
+	[COL_BYID] = { "ID-LINK", 0.1, SCOLS_FL_NOEXTREMES, N_("udev by-id link") },
 	[COL_DALIGN] = { "DISC-ALN", 6, SCOLS_FL_RIGHT, N_("discard alignment offset"), COLTYPE_NUM },
 	[COL_DAX] = { "DAX", 1, SCOLS_FL_RIGHT, N_("dax-capable device"), COLTYPE_BOOL },
 	[COL_DGRAN] = { "DISC-GRAN", 6, SCOLS_FL_RIGHT, N_("discard granularity"), COLTYPE_SIZE },
@@ -927,6 +929,11 @@ static char *device_get_data(
 		if (prop && prop->wwn)
 			str = xstrdup(prop->wwn);
 		break;
+	case COL_BYID:
+		prop = lsblk_device_get_properties(dev);
+		if (prop && prop->byid)
+			str = xstrdup(prop->byid);
+		break;
 	case COL_RA:
 		ul_path_read_string(dev->sysfs, &str, "queue/read_ahead_kb");
 		if (sortdata)
diff --git a/misc-utils/lsblk.h b/misc-utils/lsblk.h
index 0ffe380088..873c9ab0ec 100644
--- a/misc-utils/lsblk.h
+++ b/misc-utils/lsblk.h
@@ -75,6 +75,7 @@ struct lsblk_devprop {
 	char *wwn;		/* storage WWN */
 	char *serial;		/* disk serial number */
 	char *model;		/* disk model */
+	char *byid;		/* /dev/disk/by-id/<name> */
 
 	/* lsblk specific (for --sysroot only)  */
 	char *owner;		/* user name */