Feature #2479: Allow CONTEXT/DEV_PREFIX, and make 'hd' the default prefix for cdrom type disks

(cherry picked from commit bc6ae465d9)

include/ImagePool.h

@@ -185,6 +185,11 @@ public:
         return _default_dev_prefix;
     };
 
+    static const string& default_cdrom_dev_prefix()
+    {
+        return _default_cdrom_dev_prefix;
+    };
+
     /**
      *  Get the effective uid to get an image. Used in VM parsers
      *    @param disk a vector attribute with the image data
@@ -215,6 +220,11 @@ private:
      **/
     static string  _default_dev_prefix;
 
+    /**
+     * Default device prefix for cdrom disks
+     **/
+    static string _default_cdrom_dev_prefix;
+
     /**
      * Image attributes to be inherited into the VM disk
      */

src/image/Image.cc

@@ -148,8 +148,18 @@ int Image::insert(SqlDB *db, string& error_str)
 
             if( dev_prefix.empty() )
             {
-                SingleAttribute * dev_att = new SingleAttribute("DEV_PREFIX",
-                                              ImagePool::default_dev_prefix());
+                if (type == CDROM)
+                {
+                    dev_prefix = ImagePool::default_cdrom_dev_prefix();
+                }
+                else
+                {
+                    dev_prefix = ImagePool::default_dev_prefix();
+                }
+
+                SingleAttribute * dev_att =
+                        new SingleAttribute("DEV_PREFIX", dev_prefix);
+
                 obj_template->set(dev_att);
             }
         break;
@@ -508,7 +518,14 @@ int Image::disk_attribute(  VectorAttribute *       disk,
 
         if (dev_prefix.empty())//Removed from image template, get it again
         {
-            dev_prefix = ImagePool::default_dev_prefix();
+            if ( type == CDROM )
+            {
+                dev_prefix = ImagePool::default_cdrom_dev_prefix();
+            }
+            else
+            {
+                dev_prefix = ImagePool::default_dev_prefix();
+            }
         }
 
         disk->replace("DEV_PREFIX", dev_prefix);

src/image/ImagePool.cc

@@ -27,6 +27,7 @@
 /* -------------------------------------------------------------------------- */
 string ImagePool::_default_type;
 string ImagePool::_default_dev_prefix;
+string ImagePool::_default_cdrom_dev_prefix;
 
 /* -------------------------------------------------------------------------- */
 /* -------------------------------------------------------------------------- */
@@ -46,6 +47,8 @@ ImagePool::ImagePool(
     _default_type       = __default_type;
     _default_dev_prefix = __default_dev_prefix;
 
+    _default_cdrom_dev_prefix = "hd";
+
     // Init inherit attributes
     vector<const Attribute *>::const_iterator it;
 

src/vm/VirtualMachine.cc

@@ -1682,7 +1682,14 @@ int VirtualMachine::get_disk_images(string& error_str)
             }
             else
             {
-                cdrom_disks.push(make_pair(ipool->default_dev_prefix(), disk));
+                dev_prefix = disk->vector_value("DEV_PREFIX");
+
+                if ( dev_prefix.empty() )
+                {
+                    dev_prefix = ipool->default_cdrom_dev_prefix();
+                }
+
+                cdrom_disks.push(make_pair(dev_prefix, disk));
             }
 
             // Disk IDs are 0..num-1, context disk is is num