Issue #1, proper display for negative INTEGER values in derdump

Also, derdump now displays a short legend of its output format

diff --git a/derdump b/derdump
index eb7b7e3..46fd63f 100755 (executable)
--- a/derdump
+++ b/derdump
@@ -3,7 +3,8 @@
 import sys
 
 if len (sys.argv) != 2:
-       print 'Usage: ' + sys.argv [0] + 'file.der'
+       print 'Usage:  ' + sys.argv [0] + 'file.der'
+       print 'Output: MEANING: TAG ###CONTLEN @TAGOFS ^NESTING, CLASS, PRIMCONSTR'
        sys.exit (1)
 
 der = open (sys.argv [1], 'r').read (65537)
@@ -117,7 +118,7 @@ while not eof ():
        if tag_pc == 0 and leng > 0:
                print '  ' * ( len (nesting) + 1 ),
                cstr = '"'
-               ival = 0
+               ival = None
                ostr = ''
                oval = None
                while leng > 0:
@@ -127,7 +128,10 @@ while not eof ():
                                cstr = cstr + chr (ch)
                        else:
                                cstr = cstr + '.'
-                       ival = (ival << 8) | ch
+                       if ival is None:
+                               ival = -1 if ch >= 128 else 0
+                       else:
+                               ival = (ival << 8) | ch
                        if oval is None:
                                ostr = str (ch / 40) + '.' + str (ch % 40)
                                oval = 0