utils/DSAextract.py

   1 #! /usr/bin/python
   2
   3 #this is a script to extract given named nodes from a dot file, with
   4 #the associated edges.  An edge is kept iff for edge x -> y
   5 # x and y are both nodes specified to be kept.
   6
   7 #known issues: if a line contains '->' and is not an edge line
   8 #problems will occur.  If node labels do not begin with
   9 #Node this also will not work.  Since this is designed to work
  10 #on DSA dot output and not general dot files this is ok.
  11 #If you want to use this on other files rename the node labels
  12 #to Node[.*] with a script or something.  This also relies on
  13 #the length of a node name being 13 characters (as it is in all
  14 #DSA dot output files)
  15
  16 #Note that the name of the node can be any substring of the actual
  17 #name in the dot file.  Thus if you say specify COLLAPSED
  18 #as a parameter this script will pull out all COLLAPSED
  19 #nodes in the file
  20
  21 #Specifying escape characters in the name like \n also will not work,
  22 #as Python
  23 #will make it \\n, I'm not really sure how to fix this
  24
  25 #currently the script prints the names it is searching for
  26 #to STDOUT, so you can check to see if they are what you intend
  27
  28 import re
  29 import string
  30 import sys
  31
  32
  33 if len(sys.argv) < 3:
  34         print 'usage is ./DSAextract <dot_file_to_modify> \
  35                         <output_file> [list of nodes to extract]'
  36
  37 #open the input file
  38 input = open(sys.argv[1], 'r')
  39
  40 #construct a set of node names
  41 node_name_set = set()
  42 for name in sys.argv[3:]:
  43         node_name_set |= set([name])
  44
  45 #construct a list of compiled regular expressions from the
  46 #node_name_set
  47 regexp_list = []
  48 for name in node_name_set:
  49         regexp_list.append(re.compile(name))
  50
  51 #used to see what kind of line we are on
  52 nodeexp = re.compile('Node')
  53 #used to check to see if the current line is an edge line
  54 arrowexp = re.compile('->')
  55
  56 node_set = set()
  57
  58 #read the file one line at a time
  59 buffer = input.readline()
  60 while buffer != '':
  61         #filter out the unecessary checks on all the edge lines
  62         if not arrowexp.search(buffer):
  63                 #check to see if this is a node we are looking for
  64                 for regexp in regexp_list:
  65                         #if this name is for the current node, add the dot variable name
  66                         #for the node (it will be Node(hex number)) to our set of nodes
  67                         if regexp.search(buffer):
  68                                 node_set |= set([re.split('\s+',buffer,2)[1]])
  69                                 break
  70         buffer = input.readline()
  71
  72
  73 #test code
  74 #print '\n'
  75
  76 print node_name_set
  77
  78 #print node_set
  79
  80
  81 #open the output file
  82 output = open(sys.argv[2], 'w')
  83 #start the second pass over the file
  84 input = open(sys.argv[1], 'r')
  85
  86 buffer = input.readline()
  87 while buffer != '':
  88         #there are three types of lines we are looking for
  89         #1) node lines, 2) edge lines 3) support lines (like page size, etc)
  90
  91         #is this an edge line?
  92         #note that this is no completely robust, if a none edge line
  93         #for some reason contains -> it will be missidentified
  94         #hand edit the file if this happens
  95         if arrowexp.search(buffer):
  96                 #check to make sure that both nodes are in the node list
  97                 #if they are print this to output
  98                 nodes = arrowexp.split(buffer)
  99                 nodes[0] = string.strip(nodes[0])
 100                 nodes[1] = string.strip(nodes[1])
 101                 if nodes[0][:13] in node_set and \
 102                                 nodes[1][:13] in node_set:
 103                                         output.write(buffer)
 104         elif nodeexp.search(buffer): #this is a node line
 105                 node = re.split('\s+', buffer,2)[1]
 106                 if node in node_set:
 107                         output.write(buffer)
 108         else: #this is a support line
 109                 output.write(buffer)
 110         buffer = input.readline()
 111