"""Utilities for comparing files and directories. Classes:    dircmp Functions:    cmp(f1, f2, shallow=1) -> int    cmpfiles(a, b, common) -> ([], [], []) """ import osimport statimport warningsfrom itertools import ifilter, ifilterfalse, imap, izip __all__ = ["cmp","dircmp","cmpfiles"] _cache = {}BUFSIZE=8*1024 def cmp(f1, f2, shallow=1):    """Compare two files.     Arguments:     f1 -- First file name     f2 -- Second file name     shallow -- Just check stat signature (do not read the files).               defaults to 1.     Return value:     True if the files are the same, False otherwise.     This function uses a cache for past comparisons and the results,    with a cache invalidation mechanism relying on stale signatures.     """     s1 = _sig(os.stat(f1))    s2 = _sig(os.stat(f2))    if s1[0] != stat.S_IFREG or s2[0] != stat.S_IFREG:        return False    if shallow and s1 == s2:        return True    if s1[1] != s2[1]:        return False     result = _cache.get((f1, f2))    if result and (s1, s2) == result[:2]:        return result[2]    outcome = _do_cmp(f1, f2)    _cache[f1, f2] = s1, s2, outcome    return outcome def _sig(st):    return (stat.S_IFMT(st.st_mode),            st.st_size,            st.st_mtime) def _do_cmp(f1, f2):    bufsize = BUFSIZE    fp1 = open(f1, 'rb')    fp2 = open(f2, 'rb')    while True:        b1 = fp1.read(bufsize)        b2 = fp2.read(bufsize)        if b1 != b2:            return False        if not b1:            return True # Directory comparison class.#class dircmp:    """A class that manages the comparison of 2 directories.     dircmp(a,b,ignore=None,hide=None)      A and B are directories.      IGNORE is a list of names to ignore,        defaults to ['RCS', 'CVS', 'tags'].      HIDE is a list of names to hide,        defaults to [os.curdir, os.pardir].     High level usage:      x = dircmp(dir1, dir2)      x.report() -> prints a report on the differences between dir1 and dir2       or      x.report_partial_closure() -> prints report on differences between dir1            and dir2, and reports on common immediate subdirectories.      x.report_full_closure() -> like report_partial_closure,            but fully recursive.     Attributes:     left_list, right_list: The files in dir1 and dir2,        filtered by hide and ignore.     common: a list of names in both dir1 and dir2.     left_only, right_only: names only in dir1, dir2.     common_dirs: subdirectories in both dir1 and dir2.     common_files: files in both dir1 and dir2.     common_funny: names in both dir1 and dir2 where the type differs between        dir1 and dir2, or the name is not stat-able.     same_files: list of identical files.     diff_files: list of filenames which differ.     funny_files: list of files which could not be compared.     subdirs: a dictionary of dircmp objects, keyed by names in common_dirs.     """     def __init__(self, a, b, ignore=None, hide=None): # Initialize        self.left = a        self.right = b        if hide is None:            self.hide = [os.curdir, os.pardir] # Names never to be shown        else:            self.hide = hide        if ignore is None:            self.ignore = ['RCS', 'CVS', 'tags'] # Names ignored in comparison        else:            self.ignore = ignore     def phase0(self): # Compare everything except common subdirectories        self.left_list = _filter(os.listdir(self.left),                                 self.hide+self.ignore)        self.right_list = _filter(os.listdir(self.right),                                  self.hide+self.ignore)        self.left_list.sort()        self.right_list.sort()     def phase1(self): # Compute common names        a = dict(izip(imap(os.path.normcase, self.left_list), self.left_list))        b = dict(izip(imap(os.path.normcase, self.right_list), self.right_list))        self.common = map(a.__getitem__, ifilter(b.has_key, a))        self.left_only = map(a.__getitem__, ifilterfalse(b.has_key, a))        self.right_only = map(b.__getitem__, ifilterfalse(a.has_key, b))     def phase2(self): # Distinguish files, directories, funnies        self.common_dirs = []        self.common_files = []        self.common_funny = []         for x in self.common:            a_path = os.path.join(self.left, x)            b_path = os.path.join(self.right, x)             ok = 1            try:                a_stat = os.stat(a_path)            except os.error, why:                # print 'Can\'t stat', a_path, ':', why[1]                ok = 0            try:                b_stat = os.stat(b_path)            except os.error, why:                # print 'Can\'t stat', b_path, ':', why[1]                ok = 0             if ok:                a_type = stat.S_IFMT(a_stat.st_mode)                b_type = stat.S_IFMT(b_stat.st_mode)                if a_type != b_type:                    self.common_funny.append(x)                elif stat.S_ISDIR(a_type):                    self.common_dirs.append(x)                elif stat.S_ISREG(a_type):                    self.common_files.append(x)                else:                    self.common_funny.append(x)            else:                self.common_funny.append(x)     def phase3(self): # Find out differences between common files        xx = cmpfiles(self.left, self.right, self.common_files)        self.same_files, self.diff_files, self.funny_files = xx     def phase4(self): # Find out differences between common subdirectories        # A new dircmp object is created for each common subdirectory,        # these are stored in a dictionary indexed by filename.        # The hide and ignore properties are inherited from the parent        self.subdirs = {}        for x in self.common_dirs:            a_x = os.path.join(self.left, x)            b_x = os.path.join(self.right, x)            self.subdirs[x]  = dircmp(a_x, b_x, self.ignore, self.hide)     def phase4_closure(self): # Recursively call phase4() on subdirectories        self.phase4()        for sd in self.subdirs.itervalues():            sd.phase4_closure()     def report(self): # Print a report on the differences between a and b        # Output format is purposely lousy        print 'diff', self.left, self.right        if self.left_only:            self.left_only.sort()            print 'Only in', self.left, ':', self.left_only        if self.right_only:            self.right_only.sort()            print 'Only in', self.right, ':', self.right_only        if self.same_files:            self.same_files.sort()            print 'Identical files :', self.same_files        if self.diff_files:            self.diff_files.sort()            print 'Differing files :', self.diff_files        if self.funny_files:            self.funny_files.sort()            print 'Trouble with common files :', self.funny_files        if self.common_dirs:            self.common_dirs.sort()            print 'Common subdirectories :', self.common_dirs        if self.common_funny:            self.common_funny.sort()            print 'Common funny cases :', self.common_funny     def report_partial_closure(self): # Print reports on self and on subdirs        self.report()        for sd in self.subdirs.itervalues():            print            sd.report()     def report_full_closure(self): # Report on self and subdirs recursively        self.report()        for sd in self.subdirs.itervalues():            print            sd.report_full_closure()     methodmap = dict(subdirs=phase4,                     same_files=phase3, diff_files=phase3, funny_files=phase3,                     common_dirs = phase2, common_files=phase2, common_funny=phase2,                     common=phase1, left_only=phase1, right_only=phase1,                     left_list=phase0, right_list=phase0)     def __getattr__(self, attr):        if attr not in self.methodmap:            raise AttributeError, attr        self.methodmap[attr](self)        return getattr(self, attr) def cmpfiles(a, b, common, shallow=1):    """Compare common files in two directories.     a, b -- directory names    common -- list of file names found in both directories    shallow -- if true, do comparison based solely on stat() information     Returns a tuple of three lists:      files that compare equal      files that are different      filenames that aren't regular files.     """    res = ([], [], [])    for x in common:        ax = os.path.join(a, x)        bx = os.path.join(b, x)        res[_cmp(ax, bx, shallow)].append(x)    return res  # Compare two files.# Return:#       0 for equal#       1 for different#       2 for funny cases (can't stat, etc.)#def _cmp(a, b, sh, abs=abs, cmp=cmp):    try:        return not abs(cmp(a, b, sh))    except os.error:        return 2  # Return a copy with items that occur in skip removed.#def _filter(flist, skip):    return list(ifilterfalse(skip.__contains__, flist))  # Demonstration and testing.#def demo():    import sys    import getopt    options, args = getopt.getopt(sys.argv[1:], 'r')    if len(args) != 2:        raise getopt.GetoptError('need exactly two args', None)    dd = dircmp(args[0], args[1])    if ('-r', '') in options:        dd.report_full_closure()    else:        dd.report() if __name__ == '__main__':    demo()