Merge pull request #11 from AhmedKamal1432/amahi-8

 Shift the start_sector if it on the partition_table size

app/controllers/disk_wizard_controller.rb

@@ -149,10 +149,10 @@ def process_disk
           # send start sector as to be able to know which partition to mount
           device = Device.find_with_unallocated(user_selections['disk'])
           @selected_disk = (device.partitions.select{|part| part.identifier == user_selections['identifier'] }).first
-          start_sector = @selected_disk.start_sector
+          end_sector = @selected_disk.end_sector
         end
 
-        para = {path: path, label: label, start_sector: start_sector}
+        para = {path: path, label: label, end_sector: end_sector}
         job_name = :mount_job
         jobs_queue.enqueue({job_name: job_name, job_para: para})
       end

app/models/device.rb

@@ -3,11 +3,6 @@
 class Device #< ActiveRecord::Base
   include Operation
 
-  MEGA_BYTE = 1024 *1024
-  TERA_BYTE = 1024 *1024 * 1024 *1024
-  # 2 Tera byte is the edge between MBR and GPT
-  GPT_EDGE = 2 * TERA_BYTE
-
   # Device attributes:
   #   vendor : Device vendor i.e. Western Digital Technologies
   #   model : Device model i.e. WDBLWE0120JCH
@@ -85,8 +80,12 @@ def full_format fstype, label = nil
   end
 
   def create_partition(size = nil, type = Partition.PartitionType[:TYPE_PRIMARY])
+    # Shift start sector if it is on the patition table size
+    new_start_sector = [self.megabyte_to_sectors(PARTITION_TABLE_SIZE_MB), size[:start_sector].to_i].max
+    raise "cannot create a partition with negative size" if size[:end_sector].to_i < new_start_sector
+
     old_partitions = Device.find(self.path).partitions
-    DiskUtils.create_partition self, size[:start_sector], size[:end_sector]
+    DiskUtils.create_partition self, new_start_sector, size[:end_sector]
     new_partitions = Device.find(self.path).partitions
     # Return the newest partitions that is just add to the device
     return  new_partitions.reject {|part| old_partitions.include? part}.first
@@ -124,10 +123,10 @@ def mount_job params_hash
     Device.progress = 60
     kname = @kname
     DebugLogger.info "|#{self.class.name}|>|#{__method__}|:New partition Label #{params_hash[:label]}"
-    unless params_hash[:start_sector].blank?
+    unless params_hash[:end_sector].blank?
       # mount new partition
      device =  Device.find_with_unallocated "/dev/#{self.kname}"
-     new_partition = device.partitions.select{|part| part.start_sector.to_i == params_hash[:start_sector].to_i}.first
+     new_partition = device.partitions.select{|part| part.end_sector.to_i == params_hash[:end_sector].to_i}.first
     else
       new_partition = self.partitions.last
     end
@@ -141,11 +140,6 @@ def delete_all_partitions
     end
   end
 
-  def megabyte_to_sectors number_of_megas
-    sector_size = DiskUtils.get_sector_size self.kname
-    return (MEGA_BYTE * number_of_megas) / sector_size.to_i
-  end
-
   class << self
     def find_with_unallocated device_path
       DebugLogger.info "|#{self.class.name}|>|#{__method__}|:find = #{device_path}"

lib/modules/operation.rb

@@ -1,5 +1,15 @@
 module Operation
+
+  MEGA_BYTE = 1024 *1024
+  TERA_BYTE = 1024 *1024 * 1024 *1024
+  # 2 Tera byte is the edge between MBR and GPT
+  GPT_EDGE = 2 * TERA_BYTE
+
+  # the space in MB that we let it to the partition table
+  PARTITION_TABLE_SIZE_MB = 2
+
   DRIVE_MOUNT_ROOT = "/var/hda/files/drives"
+
   # Remove the partition from device/disk
   def delete
     #TODO: remove fstab entry if disk is permanently mounted
@@ -43,6 +53,16 @@ def self.included(base)
     base.extend(ClassMethods)
   end
 
+  def megabyte_to_sectors number_of_megas
+    if self.instance_of? Partition
+      device = self.device
+    else
+      device = self
+    end
+    sector_size = DiskUtils.get_sector_size device.kname
+    return (MEGA_BYTE * number_of_megas) / sector_size.to_i
+  end
+
   def pre_checks_job params_hash
     DebugLogger.info "|#{self.class.name}|>|#{__method__}|:Params_hash #{params_hash}"
     # TODO: Implement rollback mechanism, if something went wrong bring back the system to original state,where it was before stating DW
@@ -70,7 +90,7 @@ def pre_checks_job params_hash
   def create_new_partition_job params_hash
     device = Device.find params_hash[:path]
     raise "We don't support GPT yet" if device.partition_table != "msdos"
-    raise "We don't support extended partitions yet, The number of partitions >= 3" if device.partition_count > 2
+    raise "You already reached partitions count limit, you have #{device.partition_count} partitions" if device.partition_count >= 4
     DebugLogger.info "|#{self.class.name}|>|#{__method__}|:Params_hash #{params_hash}"
 
     device = Device.find_with_unallocated params_hash[:path]