Add netrc.py from CPython 3.8

coolreader18 · coolreader18 · commit 84a5a2c8d623 · 2021-02-20T21:04:29.000-06:00
diff --git a/Lib/netrc.py b/Lib/netrc.py
@@ -0,0 +1,139 @@
+"""An object-oriented interface to .netrc files."""
+
+# Module and documentation by Eric S. Raymond, 21 Dec 1998
+
+import os, shlex, stat
+
+__all__ = ["netrc", "NetrcParseError"]
+
+
+class NetrcParseError(Exception):
+    """Exception raised on syntax errors in the .netrc file."""
+    def __init__(self, msg, filename=None, lineno=None):
+        self.filename = filename
+        self.lineno = lineno
+        self.msg = msg
+        Exception.__init__(self, msg)
+
+    def __str__(self):
+        return "%s (%s, line %s)" % (self.msg, self.filename, self.lineno)
+
+
+class netrc:
+    def __init__(self, file=None):
+        default_netrc = file is None
+        if file is None:
+            file = os.path.join(os.path.expanduser("~"), ".netrc")
+        self.hosts = {}
+        self.macros = {}
+        with open(file) as fp:
+            self._parse(file, fp, default_netrc)
+
+    def _parse(self, file, fp, default_netrc):
+        lexer = shlex.shlex(fp)
+        lexer.wordchars += r"""!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"""
+        lexer.commenters = lexer.commenters.replace('#', '')
+        while 1:
+            # Look for a machine, default, or macdef top-level keyword
+            saved_lineno = lexer.lineno
+            toplevel = tt = lexer.get_token()
+            if not tt:
+                break
+            elif tt[0] == '#':
+                if lexer.lineno == saved_lineno and len(tt) == 1:
+                    lexer.instream.readline()
+                continue
+            elif tt == 'machine':
+                entryname = lexer.get_token()
+            elif tt == 'default':
+                entryname = 'default'
+            elif tt == 'macdef':                # Just skip to end of macdefs
+                entryname = lexer.get_token()
+                self.macros[entryname] = []
+                lexer.whitespace = ' \t'
+                while 1:
+                    line = lexer.instream.readline()
+                    if not line or line == '\012':
+                        lexer.whitespace = ' \t\r\n'
+                        break
+                    self.macros[entryname].append(line)
+                continue
+            else:
+                raise NetrcParseError(
+                    "bad toplevel token %r" % tt, file, lexer.lineno)
+
+            # We're looking at start of an entry for a named machine or default.
+            login = ''
+            account = password = None
+            self.hosts[entryname] = {}
+            while 1:
+                tt = lexer.get_token()
+                if (tt.startswith('#') or
+                    tt in {'', 'machine', 'default', 'macdef'}):
+                    if password:
+                        self.hosts[entryname] = (login, account, password)
+                        lexer.push_token(tt)
+                        break
+                    else:
+                        raise NetrcParseError(
+                            "malformed %s entry %s terminated by %s"
+                            % (toplevel, entryname, repr(tt)),
+                            file, lexer.lineno)
+                elif tt == 'login' or tt == 'user':
+                    login = lexer.get_token()
+                elif tt == 'account':
+                    account = lexer.get_token()
+                elif tt == 'password':
+                    if os.name == 'posix' and default_netrc:
+                        prop = os.fstat(fp.fileno())
+                        if prop.st_uid != os.getuid():
+                            import pwd
+                            try:
+                                fowner = pwd.getpwuid(prop.st_uid)[0]
+                            except KeyError:
+                                fowner = 'uid %s' % prop.st_uid
+                            try:
+                                user = pwd.getpwuid(os.getuid())[0]
+                            except KeyError:
+                                user = 'uid %s' % os.getuid()
+                            raise NetrcParseError(
+                                ("~/.netrc file owner (%s) does not match"
+                                 " current user (%s)") % (fowner, user),
+                                file, lexer.lineno)
+                        if (prop.st_mode & (stat.S_IRWXG | stat.S_IRWXO)):
+                            raise NetrcParseError(
+                               "~/.netrc access too permissive: access"
+                               " permissions must restrict access to only"
+                               " the owner", file, lexer.lineno)
+                    password = lexer.get_token()
+                else:
+                    raise NetrcParseError("bad follower token %r" % tt,
+                                          file, lexer.lineno)
+
+    def authenticators(self, host):
+        """Return a (user, account, password) tuple for given host."""
+        if host in self.hosts:
+            return self.hosts[host]
+        elif 'default' in self.hosts:
+            return self.hosts['default']
+        else:
+            return None
+
+    def __repr__(self):
+        """Dump the class data in the format of a .netrc file."""
+        rep = ""
+        for host in self.hosts.keys():
+            attrs = self.hosts[host]
+            rep += f"machine {host}\n\tlogin {attrs[0]}\n"
+            if attrs[1]:
+                rep += f"\taccount {attrs[1]}\n"
+            rep += f"\tpassword {attrs[2]}\n"
+        for macro in self.macros.keys():
+            rep += f"macdef {macro}\n"
+            for line in self.macros[macro]:
+                rep += line
+            rep += "\n"
+        return rep
+
+if __name__ == '__main__':
+    print(netrc())
