windows: Shrink the volume without using querymax

Shrink volume as much as possible and then extend it 100MB. We used to
do a querymax to see how much we could shrink the volume and then
compute the desired shrinking size, but this leaded to problems. We had
to parse the output of "shrink querymax" which is in a localized natural
language format.

This fixes #53

image_creator/os_type/windows/__init__.py

@@ -393,73 +393,17 @@ class Windows(OSBase):
         defragged.
         """
 
-        # Query for the maximum number of reclaimable bytes
-        cmd = (
-            r'cmd /Q /V:ON /C "SET SCRIPT=%TEMP%\QUERYMAX_%RANDOM%.TXT & ' +
-            r'ECHO SELECT DISK 0 > %SCRIPT% & ' +
-            'ECHO SELECT PARTITION %d >> %%SCRIPT%% & ' % self.last_part_num +
-            r'ECHO SHRINK QUERYMAX >> %SCRIPT% & ' +
-            r'ECHO EXIT >> %SCRIPT% & ' +
-            r'DISKPART /S %SCRIPT% & ' +
-            r'IF NOT !ERRORLEVEL! EQU 0 EXIT /B 1 & ' +
-            r'DEL /Q %SCRIPT%"')
-
-        stdout, stderr, rc = self.vm.rexec(cmd)
-
-        querymax = None
-        expr = re.compile(
-            r'.+:\s*(\d+)\s*([KMGT]?)B\s*(?:\((\d+)\s*([KMGT]?)B\))?\s*$')
-        for line in stdout.splitlines():
-            # diskpart will return something like this:
-            #
-            # a) The maximum number of reclaimable bytes is: xxxx MB
-            # b) The maximum number of reclaimable bytes is: xxxx GB (xxxx MB)
-
-            match = expr.match(line)
-            if match:
-                offset = 0 if match.group(3) is None else 2
-                querymax = match.group(offset+1)
-                unit = match.group(offset+2)
-                break
-
-        if querymax is None:
-            raise FatalError("Error in shrinking! Couldn't find the max "
-                             "number of reclaimable bytes!\n"
-                             "Command output: %s" % stdout)
-
-        querymax = int(querymax)
-        if querymax == 0:
-            self.out.warn("Unable to reclaim any space. The media is full.")
-            return
-
-        # Not sure if we should use 1000 or 1024 here
-        if len(unit) == 0:  # Bytes
-            querymax /= 1000 * 1000
-        elif unit == 'K':
-            querymax /= 1000
-        elif unit == 'G':
-            querymax *= 1000
-        elif unit == 'T':
-            querymax *= 1000*1000
-
+        # Shrink the volume as much as possible and then give 100MB back.
         # From ntfsresize:
         # Practically the smallest shrunken size generally is at around
         # "used space" + (20-200 MB). Please also take into account that
         # Windows might need about 50-100 MB free space left to boot safely.
-        # I'll give 100MB extra space just to be sure
-        querymax -= 100
-
-        if querymax < 0:
-            self.out.warn("Not enough available space to shrink the image!")
-            return
-
-        self.out.info("\tReclaiming %dMB ..." % querymax)
-
         cmd = (
             r'cmd /Q /V:ON /C "SET SCRIPT=%TEMP%\QUERYMAX_%RANDOM%.TXT & ' +
             r'ECHO SELECT DISK 0 > %SCRIPT% & ' +
             'ECHO SELECT PARTITION %d >> %%SCRIPT%% & ' % self.last_part_num +
-            'ECHO SHRINK DESIRED=%d >> %%SCRIPT%% & ' % querymax +
+            r'ECHO SHRINK NOERR >> %SCRIPT% & ' +
+            r'ECHO EXTEND SIZE=100 NOERR >> %SCRIPT% & ' +
             r'ECHO EXIT >> %SCRIPT% & ' +
             r'DISKPART /S %SCRIPT% & ' +
             r'IF NOT !ERRORLEVEL! EQU 0 EXIT /B 1 & ' +
@@ -472,8 +416,10 @@ class Windows(OSBase):
                 "Shrinking failed. Please make sure the media is defragged.")
 
         for line in stdout.splitlines():
-            if line.find("%d" % querymax) >= 0:
-                self.out.info(" %s" % line)
+            line = line.strip()
+            if not len(line):
+                continue
+            self.out.info(" %s" % line)
 
         self.shrinked = True