Tools/scripts/h2py.py

   1 #! /usr/bin/env 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, re, getopt, os
  25
  26 p_define = re.compile('^[\t ]*#[\t ]*define[\t ]+([a-zA-Z0-9_]+)[\t ]+')
  27
  28 p_macro = re.compile(
  29   '^[\t ]*#[\t ]*define[\t ]+'
  30   '([a-zA-Z0-9_]+)\(([_a-zA-Z][_a-zA-Z0-9]*)\)[\t ]+')
  31
  32 p_include = re.compile('^[\t ]*#[\t ]*include[\t ]+<([a-zA-Z0-9_/\.]+)')
  33
  34 p_comment = re.compile(r'/\*([^*]+|\*+[^/])*(\*+/)?')
  35 p_cpp_comment = re.compile('//.*')
  36
  37 ignores = [p_comment, p_cpp_comment]
  38
  39 p_char = re.compile(r"'(\\.[^\\]*|[^\\])'")
  40
  41 p_hex = re.compile(r"0x([0-9a-fA-F]+)L?")
  42
  43 filedict = {}
  44 importable = {}
  45
  46 try:
  47     searchdirs=os.environ['include'].split(';')
  48 except KeyError:
  49     try:
  50         searchdirs=os.environ['INCLUDE'].split(';')
  51     except KeyError:
  52         try:
  53             if  sys.platform.find("beos") == 0:
  54                 searchdirs=os.environ['BEINCLUDES'].split(';')
  55             elif sys.platform.startswith("atheos"):
  56                 searchdirs=os.environ['C_INCLUDE_PATH'].split(':')
  57             else:
  58                 raise KeyError
  59         except KeyError:
  60             searchdirs=['/usr/include']
  61
  62 def main():
  63     global filedict
  64     opts, args = getopt.getopt(sys.argv[1:], 'i:')
  65     for o, a in opts:
  66         if o == '-i':
  67             ignores.append(re.compile(a))
  68     if not args:
  69         args = ['-']
  70     for filename in args:
  71         if filename == '-':
  72             sys.stdout.write('# Generated by h2py from stdin\n')
  73             process(sys.stdin, sys.stdout)
  74         else:
  75             fp = open(filename, 'r')
  76             outfile = os.path.basename(filename)
  77             i = outfile.rfind('.')
  78             if i > 0: outfile = outfile[:i]
  79             modname = outfile.upper()
  80             outfile = modname + '.py'
  81             outfp = open(outfile, 'w')
  82             outfp.write('# Generated by h2py from %s\n' % filename)
  83             filedict = {}
  84             for dir in searchdirs:
  85                 if filename[:len(dir)] == dir:
  86                     filedict[filename[len(dir)+1:]] = None  # no '/' trailing
  87                     importable[filename[len(dir)+1:]] = modname
  88                     break
  89             process(fp, outfp)
  90             outfp.close()
  91             fp.close()
  92
  93 def pytify(body):
  94     # replace ignored patterns by spaces
  95     for p in ignores:
  96         body = p.sub(' ', body)
  97     # replace char literals by ord(...)
  98     body = p_char.sub('ord(\\0)', body)
  99     # Compute negative hexadecimal constants
 100     start = 0
 101     UMAX = 2*(sys.maxint+1)
 102     while 1:
 103         m = p_hex.search(body, start)
 104         if not m: break
 105         s,e = m.span()
 106         val = long(body[slice(*m.span(1))], 16)
 107         if val > sys.maxint:
 108             val -= UMAX
 109             body = body[:s] + "(" + str(val) + ")" + body[e:]
 110         start = s + 1
 111     return body
 112
 113 def process(fp, outfp, env = {}):
 114     lineno = 0
 115     while 1:
 116         line = fp.readline()
 117         if not line: break
 118         lineno = lineno + 1
 119         match = p_define.match(line)
 120         if match:
 121             # gobble up continuation lines
 122             while line[-2:] == '\\\n':
 123                 nextline = fp.readline()
 124                 if not nextline: break
 125                 lineno = lineno + 1
 126                 line = line + nextline
 127             name = match.group(1)
 128             body = line[match.end():]
 129             body = pytify(body)
 130             ok = 0
 131             stmt = '%s = %s\n' % (name, body.strip())
 132             try:
 133                 exec stmt in env
 134             except:
 135                 sys.stderr.write('Skipping: %s' % stmt)
 136             else:
 137                 outfp.write(stmt)
 138         match = p_macro.match(line)
 139         if match:
 140             macro, arg = match.group(1, 2)
 141             body = line[match.end():]
 142             body = pytify(body)
 143             stmt = 'def %s(%s): return %s\n' % (macro, arg, body)
 144             try:
 145                 exec stmt in env
 146             except:
 147                 sys.stderr.write('Skipping: %s' % stmt)
 148             else:
 149                 outfp.write(stmt)
 150         match = p_include.match(line)
 151         if match:
 152             regs = match.regs
 153             a, b = regs[1]
 154             filename = line[a:b]
 155             if importable.has_key(filename):
 156                 outfp.write('from %s import *\n' % importable[filename])
 157             elif not filedict.has_key(filename):
 158                 filedict[filename] = None
 159                 inclfp = None
 160                 for dir in searchdirs:
 161                     try:
 162                         inclfp = open(dir + '/' + filename)
 163                         break
 164                     except IOError:
 165                         pass
 166                 if inclfp:
 167                     outfp.write(
 168                             '\n# Included from %s\n' % filename)
 169                     process(inclfp, outfp, env)
 170                 else:
 171                     sys.stderr.write('Warning - could not find file %s\n' %
 172                                      filename)
 173
 174 if __name__ == '__main__':
 175     main()