Clean up Intel HEX utilities

No functional change intended.

stcgal/ihex.py

@@ -5,15 +5,20 @@
 import struct
 import codecs
 
-class IHex(object):
+
+class IHex:
+    """Intel HEX parser and writer"""
+
     @classmethod
     def read(cls, lines):
+        """Read Intel HEX data from string or lines"""
         ihex = cls()
 
         segbase = 0
         for line in lines:
             line = line.strip()
-      if not line: continue
+            if not line:
+                continue
 
             t, a, d = ihex.parse_line(line)
             if t == 0x00:
@@ -47,6 +52,7 @@ class IHex(object):
 
     @classmethod
     def read_file(cls, fname):
+        """Read Intel HEX data from file"""
         f = open(fname, "rb")
         ihex = cls.read(f)
         f.close()
@@ -65,6 +71,7 @@ class IHex(object):
         self.row_bytes = row_bytes
 
     def extract_data(self, start=None, end=None):
+        """Extract binary data"""
         if start is None:
             start = 0
 
@@ -74,8 +81,9 @@ class IHex(object):
             for addr, data in self.areas.items():
                 if addr >= start:
                     if len(result) < (addr - start):
-            result[len(result):addr-start] = bytes(addr-start-len(result))
+                        result[len(result):addr - start] = bytes(
-          result[addr-start:addr-start+len(data)] = data
+                            addr - start - len(result))
+                    result[addr - start:addr - start + len(data)] = data
 
             return bytes(result)
 
@@ -84,10 +92,11 @@ class IHex(object):
 
             for addr, data in self.areas.items():
                 if addr >= start and addr < end:
-          data = data[:end-addr]
+                    data = data[:end - addr]
                     if len(result) < (addr - start):
-            result[len(result):addr-start] = bytes(addr-start-len(result))
+                        result[len(result):addr - start] = bytes(
-          result[addr-start:addr-start+len(data)] = data
+                            addr - start - len(result))
+                    result[addr - start:addr - start + len(data)] = data
 
             return bytes(result)
 
@@ -115,10 +124,11 @@ class IHex(object):
         else:
             data = self.areas[area]
             # istart - iend + len(idata) + len(data)
-      self.areas[area] = data[:istart-area] + idata + data[iend-area:]
+            self.areas[area] = data[
+                :istart - area] + idata + data[iend - area:]
 
-  def calc_checksum(self, bytes):
+    def calc_checksum(self, data):
-    total = sum(bytes)
+        total = sum(data)
         return (-total) & 0xFF
 
     def parse_line(self, rawline):
@@ -126,33 +136,31 @@ class IHex(object):
             raise ValueError("Invalid line start character (%r)" % rawline[0])
 
         try:
-      #line = rawline[1:].decode("hex")
             line = codecs.decode(rawline[1:], "hex_codec")
         except:
             raise ValueError("Invalid hex data")
 
-    length, addr, type = struct.unpack(">BHB", line[:4])
+        length, addr, line_type = struct.unpack(">BHB", line[:4])
 
         dataend = length + 4
         data = line[4:dataend]
 
-    #~ print line[dataend:dataend + 2], repr(line)
         cs1 = line[dataend]
         cs2 = self.calc_checksum(line[:dataend])
 
         if cs1 != cs2:
             raise ValueError("Checksums do not match")
 
-    return (type, addr, data)
+        return (line_type, addr, data)
 
-  def make_line(self, type, addr, data):
+    def make_line(self, line_type, addr, data):
-    line = struct.pack(">BHB", len(data), addr, type)
+        line = struct.pack(">BHB", len(data), addr, line_type)
         line += data
         line += chr(self.calc_checksum(line))
-    #~ return ":" + line.encode("hex")
         return ":" + line.encode("hex").upper() + "\r\n"
 
     def write(self):
+        """Write Intel HEX data to string"""
         output = ""
 
         for start, data in sorted(self.areas.items()):
@@ -174,7 +182,8 @@ class IHex(object):
                     addr = t
 
                     if newsegbase != segbase:
-            output += self.make_line(0x02, 0, struct.pack(">H", newsegbase))
+                        output += self.make_line(
+                            0x02, 0, struct.pack(">H", newsegbase))
                         segbase = newsegbase
 
                 elif self.mode == 32:
@@ -182,7 +191,8 @@ class IHex(object):
                     addr = addr & 0xFFFF
 
                     if newsegbase != segbase:
-            output += self.make_line(0x04, 0, struct.pack(">H", newsegbase))
+                        output += self.make_line(
+                            0x04, 0, struct.pack(">H", newsegbase))
                         segbase = newsegbase
 
                 output += self.make_line(0x00, addr, chunk)
@@ -192,14 +202,17 @@ class IHex(object):
 
         if self.start is not None:
             if self.mode == 16:
-        output += self.make_line(0x03, 0, struct.pack(">2H", self.start[0], self.start[1]))
+                output += self.make_line(
+                    0x03, 0, struct.pack(">2H", self.start[0], self.start[1]))
             elif self.mode == 32:
-        output += self.make_line(0x05, 0, struct.pack(">I", self.start))
+                output += self.make_line(
+                    0x05, 0, struct.pack(">I", self.start))
 
         output += self.make_line(0x01, 0, "")
         return output
 
     def write_file(self, fname):
+        """Write Intel HEX data to file"""
         f = open(fname, "w")
         f.write(self.write())
         f.close()