From 8ef6e561100acd987ce7a388cada725975961f0b Mon Sep 17 00:00:00 2001
From: Calin Crisan <ccrisan@gmail.com>
Date: Sun, 15 Feb 2015 12:49:07 +0200
Subject: [PATCH] diskctl: implemented fallback using fdisk -l when
 /dev/disks/by-id/ is not available

---
 src/diskctl.py | 77 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 76 insertions(+), 1 deletion(-)

diff --git a/src/diskctl.py b/src/diskctl.py
index fbf9b9a..b4cd738 100644
--- a/src/diskctl.py
+++ b/src/diskctl.py
@@ -18,6 +18,7 @@
 import logging
 import os
 import re
+import subprocess
 
 
 def _list_mounts():
@@ -64,7 +65,15 @@ def _list_mounts():
 
 
 def _list_disks():
-    logging.debug('listing disks...')
+    if os.path.exists('/dev/disk/by-id/'):
+        return _list_disks_dev_by_id()
+    
+    else:  # fall back to fdisk -l
+        return _list_disks_fdisk()
+
+
+def _list_disks_dev_by_id():
+    logging.debug('listing disks using /dev/disk/by-id/')
     
     disks_by_dev = {}
     partitions_by_dev = {}
@@ -139,6 +148,72 @@ def _list_disks():
     return disks
 
 
+def _list_disks_fdisk():
+    try:
+        output = subprocess.check_output('fdisk -l 2>/dev/null', shell=True)
+    
+    except Exception as e:
+        logging.error('failed to list disks using "fdisk -l": %s' % e, exc_info=True)
+        
+        return []
+
+    disks = []
+    disk = None
+    
+    def add_disk(disk):
+        logging.debug('found disk at "%s" on bus "%s": "%s %s"' %
+                (disk['target'], disk['bus'], disk['vendor'], disk['model']))
+
+        for part in disk['partitions']:
+            logging.debug('found partition "%s" at "%s" on bus "%s": "%s %s"' %
+                    (part['part_no'], part['target'], part['bus'], part['vendor'], part['model']))
+
+        disks.append(disk)
+
+    for line in output.split('\n'):
+        line = line.replace('*', '')
+        line = re.sub('\s+', ' ', line.strip())
+        if not line:
+            continue
+
+        if line.startswith('Disk /dev/'):
+            if disk and disk['partitions']:
+                add_disk(disk)
+
+            parts = line.split()
+
+            disk = {
+                'target': parts[1].strip(':'),
+                'bus': '',
+                'vendor': '',
+                'model': parts[2] + ' ' + parts[3].strip(','),
+                'partitions': []
+            }
+            
+        elif line.startswith('/dev/') and disk:
+            parts = line.split()
+            part_no = re.findall('\d+$', parts[0])
+            partition = {
+                'part_no': int(part_no[0]) if part_no else None,
+                'target': parts[0],
+                'bus': '',
+                'vendor': '',
+                'model': parts[4] + ' ' + ' '.join(parts[6:]),
+            }
+            
+            disk['partitions'].append(partition)
+
+    if disk and disk['partitions']:
+        add_disk(disk)
+
+    disks.sort(key=lambda d: d['target'])
+
+    for disk in disks:
+        disk['partitions'].sort(key=lambda p: p['part_no'])
+
+    return disks
+
+
 def list_mounted_disks():
     mounted_disks = []
     
-- 
2.39.5