Make dfu-convert.py Python 3 capable

scripts/dfu-convert.py

@@ -1,13 +1,19 @@
-#!/usr/bin/python2
+#!/usr/bin/env python
 
 # Written by Antonio Galea - 2010/11/18
 # Distributed under Gnu LGPL 3.0
 # see http://www.gnu.org/licenses/lgpl-3.0.txt
+#
+# Add support for Python 3 inspired by script found in Bitcraze repository
 
 import sys,struct,zlib,os
 from optparse import OptionParser
 from intelhex import IntelHex
 
+python3 = False
+if (sys.version_info > (3, 0)):
+      python3 = True
+
 DEFAULT_DEVICE="0x0483:0xdf11"
 
 def named(tuple,names):
@@ -21,11 +27,11 @@ def compute_crc(data):
   return 0xFFFFFFFF & -zlib.crc32(data) -1
 
 def parse(file,dump_images=False):
-  print 'File: "%s"' % file
+  print('File: "%s"' % file)
   data = open(file,'rb').read()
   crc = compute_crc(data[:-4])
   prefix, data = consume('<5sBIB',data,'signature version size targets')
-  print '%(signature)s v%(version)d, image size: %(size)d, targets: %(targets)d' % prefix
+  print('%(signature)s v%(version)d, image size: %(size)d, targets: %(targets)d' % prefix)
   for t in range(prefix['targets']):
     tprefix, data  = consume('<6sBI255s2I',data,'signature altsetting named name size elements')
     tprefix['num'] = t
@@ -33,40 +39,57 @@ def parse(file,dump_images=False):
       tprefix['name'] = cstring(tprefix['name'])
     else:
       tprefix['name'] = ''
-    print '%(signature)s %(num)d, alt setting: %(altsetting)s, name: "%(name)s", size: %(size)d, elements: %(elements)d' % tprefix
+    print('%(signature)s %(num)d, alt setting: %(altsetting)s, name: "%(name)s", size: %(size)d, elements: %(elements)d' % tprefix)
     tsize = tprefix['size']
     target, data = data[:tsize], data[tsize:]
     for e in range(tprefix['elements']):
       eprefix, target = consume('<2I',target,'address size')
       eprefix['num'] = e
-      print '  %(num)d, address: 0x%(address)08x, size: %(size)d' % eprefix
+      print('  %(num)d, address: 0x%(address)08x, size: %(size)d' % eprefix)
       esize = eprefix['size']
       image, target = target[:esize], target[esize:]
       if dump_images:
         out = '%s.target%d.image%d.bin' % (file,t,e)
         open(out,'wb').write(image)
-        print '    DUMPED IMAGE TO "%s"' % out
+        print('    DUMPED IMAGE TO "%s"' % out)
     if len(target):
-      print "target %d: PARSE ERROR" % t
+      print("target %d: PARSE ERROR" % t)
   suffix = named(struct.unpack('<4H3sBI',data[:16]),'device product vendor dfu ufd len crc')
-  print 'usb: %(vendor)04x:%(product)04x, device: 0x%(device)04x, dfu: 0x%(dfu)04x, %(ufd)s, %(len)d, 0x%(crc)08x' % suffix
+  print('usb: %(vendor)04x:%(product)04x, device: 0x%(device)04x, dfu: 0x%(dfu)04x, %(ufd)s, %(len)d, 0x%(crc)08x' % suffix)
   if crc != suffix['crc']:
-    print "CRC ERROR: computed crc32 is 0x%08x" % crc
+    print("CRC ERROR: computed crc32 is 0x%08x" % crc)
   data = data[16:]
   if data:
-    print "PARSE ERROR"
+    print("PARSE ERROR")
 
 def build(file,targets,device=DEFAULT_DEVICE):
   data = ''
+  if (python3):
+        data = b''
   for t,target in enumerate(targets):
     tdata = ''
+    if (python3):
+          tdata = b''
     for image in target:
       tdata += struct.pack('<2I',image['address'],len(image['data']))+image['data']
-    tdata = struct.pack('<6sBI255s2I','Target',0,1,'ST...',len(tdata),len(target)) + tdata
+
+    trgt = 'Target'
+    st = 'ST...'
+    if (python3):
+      trgt = b'Target'
+      st = b'ST...'
+    tdata = struct.pack('<6sBI255s2I',trgt,0,1,st,len(tdata),len(target)) + tdata
     data += tdata
-  data  = struct.pack('<5sBIB','DfuSe',1,len(data)+11,len(targets)) + data
+
+  dfu_se = 'DfuSe'
+  ufd = 'UFD'
+  if (python3):
+    dfu_se = b'DfuSe'
+    ufd = b'UFD'
+  data  = struct.pack('<5sBIB',dfu_se,1,len(data)+11,len(targets)) + data
+
   v,d=map(lambda x: int(x,0) & 0xFFFF, device.split(':',1))
-  data += struct.pack('<4H3sB',0,d,v,0x011a,'UFD',16)
+  data += struct.pack('<4H3sB',0,d,v,0x011a,ufd,16)
   crc   = compute_crc(data)
   data += struct.pack('<I',crc)
   open(file,'wb').write(data)
@@ -96,15 +119,15 @@ if __name__=="__main__":
         try:
           address,binfile = arg.split(':',1)
         except ValueError:
-          print "Address:file couple '%s' invalid." % arg
+          print("Address:file couple '%s' invalid." % arg)
           sys.exit(1)
         try:
           address = int(address,0) & 0xFFFFFFFF
         except ValueError:
-          print "Address %s invalid." % address
+          print("Address %s invalid." % address)
           sys.exit(1)
         if not os.path.isfile(binfile):
-          print "Unreadable file '%s'." % binfile
+          print("Unreadable file '%s'." % binfile)
           sys.exit(1)
         target.append({ 'address': address, 'data': open(binfile,'rb').read() })
     
@@ -116,7 +139,7 @@ if __name__=="__main__":
         try:
           address = address & 0xFFFFFFFF
         except ValueError:
-          print "Address %s invalid." % address
+          print("Address %s invalid." % address)
           sys.exit(1)
         target.append({ 'address': address, 'data': data })
     
@@ -127,13 +150,13 @@ if __name__=="__main__":
     try:
       v,d=map(lambda x: int(x,0) & 0xFFFF, device.split(':',1))
     except:
-      print "Invalid device '%s'." % device
+      print("Invalid device '%s'." % device)
       sys.exit(1)
     build(outfile,[target],device)
   elif len(args)==1:
     infile = args[0]
     if not os.path.isfile(infile):
-      print "Unreadable file '%s'." % infile
+      print("Unreadable file '%s'." % infile)
       sys.exit(1)
     parse(infile, dump_images=options.dump_images)
   else: