1 #! /usr/bin/env python

     2 

     3 # Perform massive identifier substitution on C source files.

     4 # This actually tokenizes the files (to some extent) so it can

     5 # avoid making substitutions inside strings or comments.

     6 # Inside strings, substitutions are never made; inside comments,

     7 # it is a user option (off by default).

     8 #

     9 # The substitutions are read from one or more files whose lines,

    10 # when not empty, after stripping comments starting with #,

    11 # must contain exactly two words separated by whitespace: the

    12 # old identifier and its replacement.

    13 #

    14 # The option -r reverses the sense of the substitutions (this may be

    15 # useful to undo a particular substitution).

    16 #

    17 # If the old identifier is prefixed with a '*' (with no intervening

    18 # whitespace), then it will not be substituted inside comments.

    19 #

    20 # Command line arguments are files or directories to be processed.

    21 # Directories are searched recursively for files whose name looks

    22 # like a C file (ends in .h or .c).  The special filename '-' means

    23 # operate in filter mode: read stdin, write stdout.

    24 #

    25 # Symbolic links are always ignored (except as explicit directory

    26 # arguments).

    27 #

    28 # The original files are kept as back-up with a "~" suffix.

    29 #

    30 # Changes made are reported to stdout in a diff-like format.

    31 #

    32 # NB: by changing only the function fixline() you can turn this

    33 # into a program for different changes to C source files; by

    34 # changing the function wanted() you can make a different selection of

    35 # files.

    36 

    37 import sys

    38 import re

    39 import os

    40 from stat import *

    41 import getopt

    42 

    43 err = sys.stderr.write

    44 dbg = err

    45 rep = sys.stdout.write

    46 

    47 def usage():

    48     progname = sys.argv[0]

    49     err('Usage: ' + progname +

    50               ' [-c] [-r] [-s file] ... file-or-directory ...\n')

    51     err('\n')

    52     err('-c           : substitute inside comments\n')

    53     err('-r           : reverse direction for following -s options\n')

    54     err('-s substfile : add a file of substitutions\n')

    55     err('\n')

    56     err('Each non-empty non-comment line in a substitution file must\n')

    57     err('contain exactly two words: an identifier and its replacement.\n')

    58     err('Comments start with a # character and end at end of line.\n')

    59     err('If an identifier is preceded with a *, it is not substituted\n')

    60     err('inside a comment even when -c is specified.\n')

    61 

    62 def main():

    63     try:

    64         opts, args = getopt.getopt(sys.argv[1:], 'crs:')

    65     except getopt.error, msg:

    66         err('Options error: ' + str(msg) + '\n')

    67         usage()

    68         sys.exit(2)

    69     bad = 0

    70     if not args: # No arguments

    71         usage()

    72         sys.exit(2)

    73     for opt, arg in opts:

    74         if opt == '-c':

    75             setdocomments()

    76         if opt == '-r':

    77             setreverse()

    78         if opt == '-s':

    79             addsubst(arg)

    80     for arg in args:

    81         if os.path.isdir(arg):

    82             if recursedown(arg): bad = 1

    83         elif os.path.islink(arg):

    84             err(arg + ': will not process symbolic links\n')

    85             bad = 1

    86         else:

    87             if fix(arg): bad = 1

    88     sys.exit(bad)

    89 

    90 # Change this regular expression to select a different set of files

    91 Wanted = '^[a-zA-Z0-9_]+\.[ch]$'

    92 def wanted(name):

    93     return re.match(Wanted, name) >= 0

    94 

    95 def recursedown(dirname):

    96     dbg('recursedown(%r)\n' % (dirname,))

    97     bad = 0

    98     try:

    99         names = os.listdir(dirname)

   100     except os.error, msg:

   101         err(dirname + ': cannot list directory: ' + str(msg) + '\n')

   102         return 1

   103     names.sort()

   104     subdirs = []

   105     for name in names:

   106         if name in (os.curdir, os.pardir): continue

   107         fullname = os.path.join(dirname, name)

   108         if os.path.islink(fullname): pass

   109         elif os.path.isdir(fullname):

   110             subdirs.append(fullname)

   111         elif wanted(name):

   112             if fix(fullname): bad = 1

   113     for fullname in subdirs:

   114         if recursedown(fullname): bad = 1

   115     return bad

   116 

   117 def fix(filename):

   118 ##  dbg('fix(%r)\n' % (filename,))

   119     if filename == '-':

   120         # Filter mode

   121         f = sys.stdin

   122         g = sys.stdout

   123     else:

   124         # File replacement mode

   125         try:

   126             f = open(filename, 'r')

   127         except IOError, msg:

   128             err(filename + ': cannot open: ' + str(msg) + '\n')

   129             return 1

   130         head, tail = os.path.split(filename)

   131         tempname = os.path.join(head, '@' + tail)

   132         g = None

   133     # If we find a match, we rewind the file and start over but

   134     # now copy everything to a temp file.

   135     lineno = 0

   136     initfixline()

   137     while 1:

   138         line = f.readline()

   139         if not line: break

   140         lineno = lineno + 1

   141         while line[-2:] == '\\\n':

   142             nextline = f.readline()

   143             if not nextline: break

   144             line = line + nextline

   145             lineno = lineno + 1

   146         newline = fixline(line)

   147         if newline != line:

   148             if g is None:

   149                 try:

   150                     g = open(tempname, 'w')

   151                 except IOError, msg:

   152                     f.close()

   153                     err(tempname+': cannot create: '+

   154                         str(msg)+'\n')

   155                     return 1

   156                 f.seek(0)

   157                 lineno = 0

   158                 initfixline()

   159                 rep(filename + ':\n')

   160                 continue # restart from the beginning

   161             rep(repr(lineno) + '\n')

   162             rep('< ' + line)

   163             rep('> ' + newline)

   164         if g is not None:

   165             g.write(newline)

   166 

   167     # End of file

   168     if filename == '-': return 0 # Done in filter mode

   169     f.close()

   170     if not g: return 0 # No changes

   171 

   172     # Finishing touch -- move files

   173 

   174     # First copy the file's mode to the temp file

   175     try:

   176         statbuf = os.stat(filename)

   177         os.chmod(tempname, statbuf[ST_MODE] & 07777)

   178     except os.error, msg:

   179         err(tempname + ': warning: chmod failed (' + str(msg) + ')\n')

   180     # Then make a backup of the original file as filename~

   181     try:

   182         os.rename(filename, filename + '~')

   183     except os.error, msg:

   184         err(filename + ': warning: backup failed (' + str(msg) + ')\n')

   185     # Now move the temp file to the original file

   186     try:

   187         os.rename(tempname, filename)

   188     except os.error, msg:

   189         err(filename + ': rename failed (' + str(msg) + ')\n')

   190         return 1

   191     # Return succes

   192     return 0

   193 

   194 # Tokenizing ANSI C (partly)

   195 

   196 Identifier = '\(struct \)?[a-zA-Z_][a-zA-Z0-9_]+'

   197 String = '"\([^\n\\"]\|\\\\.\)*"'

   198 Char = '\'\([^\n\\\']\|\\\\.\)*\''

   199 CommentStart = '/\*'

   200 CommentEnd = '\*/'

   201 

   202 Hexnumber = '0[xX][0-9a-fA-F]*[uUlL]*'

   203 Octnumber = '0[0-7]*[uUlL]*'

   204 Decnumber = '[1-9][0-9]*[uUlL]*'

   205 Intnumber = Hexnumber + '\|' + Octnumber + '\|' + Decnumber

   206 Exponent = '[eE][-+]?[0-9]+'

   207 Pointfloat = '\([0-9]+\.[0-9]*\|\.[0-9]+\)\(' + Exponent + '\)?'

   208 Expfloat = '[0-9]+' + Exponent

   209 Floatnumber = Pointfloat + '\|' + Expfloat

   210 Number = Floatnumber + '\|' + Intnumber

   211 

   212 # Anything else is an operator -- don't list this explicitly because of '/*'

   213 

   214 OutsideComment = (Identifier, Number, String, Char, CommentStart)

   215 OutsideCommentPattern = '(' + '|'.join(OutsideComment) + ')'

   216 OutsideCommentProgram = re.compile(OutsideCommentPattern)

   217 

   218 InsideComment = (Identifier, Number, CommentEnd)

   219 InsideCommentPattern = '(' + '|'.join(InsideComment) + ')'

   220 InsideCommentProgram = re.compile(InsideCommentPattern)

   221 

   222 def initfixline():

   223     global Program

   224     Program = OutsideCommentProgram

   225 

   226 def fixline(line):

   227     global Program

   228 ##  print '-->', repr(line)

   229     i = 0

   230     while i < len(line):

   231         i = Program.search(line, i)

   232         if i < 0: break

   233         found = Program.group(0)

   234 ##      if Program is InsideCommentProgram: print '...',

   235 ##      else: print '   ',

   236 ##      print found

   237         if len(found) == 2:

   238             if found == '/*':

   239                 Program = InsideCommentProgram

   240             elif found == '*/':

   241                 Program = OutsideCommentProgram

   242         n = len(found)

   243         if Dict.has_key(found):

   244             subst = Dict[found]

   245             if Program is InsideCommentProgram:

   246                 if not Docomments:

   247                     print 'Found in comment:', found

   248                     i = i + n

   249                     continue

   250                 if NotInComment.has_key(found):

   251 ##                  print 'Ignored in comment:',

   252 ##                  print found, '-->', subst

   253 ##                  print 'Line:', line,

   254                     subst = found

   255 ##              else:

   256 ##                  print 'Substituting in comment:',

   257 ##                  print found, '-->', subst

   258 ##                  print 'Line:', line,

   259             line = line[:i] + subst + line[i+n:]

   260             n = len(subst)

   261         i = i + n

   262     return line

   263 

   264 Docomments = 0

   265 def setdocomments():

   266     global Docomments

   267     Docomments = 1

   268 

   269 Reverse = 0

   270 def setreverse():

   271     global Reverse

   272     Reverse = (not Reverse)

   273 

   274 Dict = {}

   275 NotInComment = {}

   276 def addsubst(substfile):

   277     try:

   278         fp = open(substfile, 'r')

   279     except IOError, msg:

   280         err(substfile + ': cannot read substfile: ' + str(msg) + '\n')

   281         sys.exit(1)

   282     lineno = 0

   283     while 1:

   284         line = fp.readline()

   285         if not line: break

   286         lineno = lineno + 1

   287         try:

   288             i = line.index('#')

   289         except ValueError:

   290             i = -1          # Happens to delete trailing \n

   291         words = line[:i].split()

   292         if not words: continue

   293         if len(words) == 3 and words[0] == 'struct':

   294             words[:2] = [words[0] + ' ' + words[1]]

   295         elif len(words) <> 2:

   296             err(substfile + '%s:%r: warning: bad line: %r' % (substfile, lineno, line))

   297             continue

   298         if Reverse:

   299             [value, key] = words

   300         else:

   301             [key, value] = words

   302         if value[0] == '*':

   303             value = value[1:]

   304         if key[0] == '*':

   305             key = key[1:]

   306             NotInComment[key] = value

   307         if Dict.has_key(key):

   308             err('%s:%r: warning: overriding: %r %r\n' % (substfile, lineno, key, value))

   309             err('%s:%r: warning: previous: %r\n' % (substfile, lineno, Dict[key]))

   310         Dict[key] = value

   311     fp.close()

   312 

   313 if __name__ == '__main__':

   314     main()