1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
"""A generic class to build line-oriented command interpreters.
Interpreters constructed with this class obey the following conventions:
1. End of file on input is processed as the command 'EOF'.
2. A command is parsed out of each line by collecting the prefix composed
of characters in the identchars member.
3. A command `foo' is dispatched to a method 'do_foo()'; the do_ method
is passed a single argument consisting of the remainder of the line.
4. Typing an empty line repeats the last command. (Actually, it calls the
method `emptyline', which may be overridden in a subclass.)
5. There is a predefined `help' method. Given an argument `topic', it
calls the command `help_topic'. With no arguments, it lists all topics
with defined help_ functions, broken into up to three topics; documented
commands, miscellaneous help topics, and undocumented commands.
6. The command '?' is a synonym for `help'. The command '!' is a synonym
for `shell', if a do_shell method exists.
The `default' method may be overridden to intercept commands for which there
is no do_ method.
The data member `self.ruler' sets the character used to draw separator lines
in the help messages. If empty, no ruler line is drawn. It defaults to "=".
If the value of `self.intro' is nonempty when the cmdloop method is called,
it is printed out on interpreter startup. This value may be overridden
via an optional argument to the cmdloop() method.
The data members `self.doc_header', `self.misc_header', and
`self.undoc_header' set the headers used for the help function's
listings of documented functions, miscellaneous topics, and undocumented
functions respectively.
These interpreters use raw_input; thus, if the readline module is loaded,
they automatically support Emacs-like command history and editing features.
"""
import string, sys
__all__ = ["Cmd"]
PROMPT = '(Cmd) '
IDENTCHARS = string.ascii_letters + string.digits + '_'
class Cmd:
prompt = PROMPT
identchars = IDENTCHARS
ruler = '='
lastcmd = ''
cmdqueue = []
intro = None
doc_leader = ""
doc_header = "Documented commands (type help <topic>):"
misc_header = "Miscellaneous help topics:"
undoc_header = "Undocumented commands:"
nohelp = "*** No help on %s"
use_rawinput = 1
def __init__(self): pass
def cmdloop(self, intro=None):
self.preloop()
if intro is not None:
self.intro = intro
if self.intro:
print self.intro
stop = None
while not stop:
if self.cmdqueue:
line = self.cmdqueue[0]
del self.cmdqueue[0]
else:
if self.use_rawinput:
try:
line = raw_input(self.prompt)
except EOFError:
line = 'EOF'
else:
sys.stdout.write(self.prompt)
line = sys.stdin.readline()
if not len(line):
line = 'EOF'
else:
line = line[:-1] # chop \n
line = self.precmd(line)
stop = self.onecmd(line)
stop = self.postcmd(stop, line)
self.postloop()
def precmd(self, line):
return line
def postcmd(self, stop, line):
return stop
def preloop(self):
pass
def postloop(self):
pass
def onecmd(self, line):
line = line.strip()
if not line:
return self.emptyline()
elif line[0] == '?':
line = 'help ' + line[1:]
elif line[0] == '!':
if hasattr(self, 'do_shell'):
line = 'shell ' + line[1:]
else:
return self.default(line)
self.lastcmd = line
i, n = 0, len(line)
while i < n and line[i] in self.identchars: i = i+1
cmd, arg = line[:i], line[i:].strip()
if cmd == '':
return self.default(line)
else:
try:
func = getattr(self, 'do_' + cmd)
except AttributeError:
return self.default(line)
return func(arg)
def emptyline(self):
if self.lastcmd:
return self.onecmd(self.lastcmd)
def default(self, line):
print '*** Unknown syntax:', line
def do_help(self, arg):
if arg:
# XXX check arg syntax
try:
func = getattr(self, 'help_' + arg)
except:
try:
doc=getattr(self, 'do_' + arg).__doc__
if doc:
print doc
return
except:
pass
print self.nohelp % (arg,)
return
func()
else:
# Inheritance says we have to look in class and
# base classes; order is not important.
names = []
classes = [self.__class__]
while classes:
aclass = classes[0]
if aclass.__bases__:
classes = classes + list(aclass.__bases__)
names = names + dir(aclass)
del classes[0]
cmds_doc = []
cmds_undoc = []
help = {}
for name in names:
if name[:5] == 'help_':
help[name[5:]]=1
names.sort()
# There can be duplicates if routines overridden
prevname = ''
for name in names:
if name[:3] == 'do_':
if name == prevname:
continue
prevname = name
cmd=name[3:]
if help.has_key(cmd):
cmds_doc.append(cmd)
del help[cmd]
elif getattr(self, name).__doc__:
cmds_doc.append(cmd)
else:
cmds_undoc.append(cmd)
print self.doc_leader
self.print_topics(self.doc_header, cmds_doc, 15,80)
self.print_topics(self.misc_header, help.keys(),15,80)
self.print_topics(self.undoc_header, cmds_undoc, 15,80)
def print_topics(self, header, cmds, cmdlen, maxcol):
if cmds:
print header
if self.ruler:
print self.ruler * len(header)
(cmds_per_line,junk)=divmod(maxcol,cmdlen)
col=cmds_per_line
for cmd in cmds:
if col==0: print
print (("%-"+`cmdlen`+"s") % cmd),
col = (col+1) % cmds_per_line
print "\n"
|
