Tools/scripts/h2py.py

   1 #! /usr/local/bin/python
   2
   3 # Read #define's and translate to Python code.
   4 # Handle #include statements.
   5 # Handle #define macros with one argument.
   6 # Anything that isn't recognized or doesn't translate into valid
   7 # Python is ignored.
   8
   9 # Without filename arguments, acts as a filter.
  10 # If one or more filenames are given, output is written to corresponding
  11 # filenames in the local directory, translated to all uppercase, with
  12 # the extension replaced by ".py".
  13
  14 # By passing one or more options of the form "-i regular_expression"
  15 # you can specify additional strings to be ignored.  This is useful
  16 # e.g. to ignore casts to u_long: simply specify "-i '(u_long)'".
  17
  18 # XXX To do:
  19 # - turn trailing C comments into Python comments
  20 # - turn C Boolean operators "&& || !" into Python "and or not"
  21 # - what to do about #if(def)?
  22 # - what to do about macros with multiple parameters?
  23
  24 import sys, regex, regsub, string, getopt, os
  25
  26 p_define = regex.compile('^#[\t ]*define[\t ]+\([a-zA-Z0-9_]+\)[\t ]+')
  27
  28 p_macro = regex.compile(
  29   '^#[\t ]*define[\t ]+\([a-zA-Z0-9_]+\)(\([_a-zA-Z][_a-zA-Z0-9]*\))[\t ]+')
  30
  31 p_include = regex.compile('^#[\t ]*include[\t ]+<\([a-zA-Z0-9_/\.]+\)')
  32
  33 p_comment = regex.compile('/\*\([^*]+\|\*+[^/]\)*\(\*+/\)?')
  34
  35 ignores = [p_comment]
  36
  37 p_char = regex.compile("'\(\\\\.[^\\\\]*\|[^\\\\]\)'")
  38
  39 filedict = {}
  40
  41 try:
  42         searchdirs=string.splitfields(os.environ['include'],';')
  43 except KeyError:
  44         try:
  45                 searchdirs=string.splitfields(os.environ['INCLUDE'],';')
  46         except KeyError:
  47                 searchdirs=['/usr/include']
  48
  49 def main():
  50         opts, args = getopt.getopt(sys.argv[1:], 'i:')
  51         for o, a in opts:
  52                 if o == '-i':
  53                         ignores.append(regex.compile(a))
  54         if not args:
  55                 args = ['-']
  56         for filename in args:
  57                 if filename == '-':
  58                         sys.stdout.write('# Generated by h2py from stdin\n')
  59                         process(sys.stdin, sys.stdout)
  60                 else:
  61                         fp = open(filename, 'r')
  62                         outfile = os.path.basename(filename)
  63                         i = string.rfind(outfile, '.')
  64                         if i > 0: outfile = outfile[:i]
  65                         outfile = string.upper(outfile)
  66                         outfile = outfile + '.py'
  67                         outfp = open(outfile, 'w')
  68                         outfp.write('# Generated by h2py from %s\n' % filename)
  69                         filedict = {}
  70                         for dir in searchdirs:
  71                                 if filename[:len(dir)] == dir:
  72                                         filedict[filename[len(dir)+1:]] = None  # no '/' trailing
  73                                         break
  74                         process(fp, outfp)
  75                         outfp.close()
  76                         fp.close()
  77
  78 def process(fp, outfp, env = {}):
  79         lineno = 0
  80         while 1:
  81                 line = fp.readline()
  82                 if not line: break
  83                 lineno = lineno + 1
  84                 n = p_define.match(line)
  85                 if n >= 0:
  86                         # gobble up continuation lines
  87                         while line[-2:] == '\\\n':
  88                                 nextline = fp.readline()
  89                                 if not nextline: break
  90                                 lineno = lineno + 1
  91                                 line = line + nextline
  92                         name = p_define.group(1)
  93                         body = line[n:]
  94                         # replace ignored patterns by spaces
  95                         for p in ignores:
  96                                 body = regsub.gsub(p, ' ', body)
  97                         # replace char literals by ord(...)
  98                         body = regsub.gsub(p_char, 'ord(\\0)', body)
  99                         stmt = '%s = %s\n' % (name, string.strip(body))
 100                         ok = 0
 101                         try:
 102                                 exec stmt in env
 103                         except:
 104                                 sys.stderr.write('Skipping: %s' % stmt)
 105                         else:
 106                                 outfp.write(stmt)
 107                 n =p_macro.match(line)
 108                 if n >= 0:
 109                         macro, arg = p_macro.group(1, 2)
 110                         body = line[n:]
 111                         for p in ignores:
 112                                 body = regsub.gsub(p, ' ', body)
 113                         body = regsub.gsub(p_char, 'ord(\\0)', body)
 114                         stmt = 'def %s(%s): return %s\n' % (macro, arg, body)
 115                         try:
 116                                 exec stmt in env
 117                         except:
 118                                 sys.stderr.write('Skipping: %s' % stmt)
 119                         else:
 120                                 outfp.write(stmt)
 121                 if p_include.match(line) >= 0:
 122                         regs = p_include.regs
 123                         a, b = regs[1]
 124                         filename = line[a:b]
 125                         if not filedict.has_key(filename):
 126                                 filedict[filename] = None
 127                                 inclfp = None
 128                                 for dir in searchdirs:
 129                                         try:
 130                                                 inclfp = open(dir + '/' + filename, 'r')
 131                                                 break
 132                                         except IOError:
 133                                                 pass
 134                                 if inclfp:
 135                                         outfp.write(
 136                                                 '\n# Included from %s\n' % filename)
 137                                         process(inclfp, outfp, env)
 138                                 else:
 139                                         sys.stderr.write('Warning - could not find file %s' % filename)
 140
 141 main()