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Advanced shell for Pythonista
import os, cmd, sys, re, glob, os.path, shutil, zipfile, tarfile, gzip
# Credits
#
# The python code here was written by pudquick@github
#
# License
#
# This code is released under a standard MIT license.
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# You can skip over reading this class, if you like.
# It's an implementation of mine of the bash parser in pure python
# This has advantages over shlex, glob, and shlex->glob in that it expects
# the strings to represent files from the start.
class BetterParser:
def __init__(self):
self.env_vars = {"$HOME": os.path.expanduser('~')}
def parse(self, instr):
instr = instr.rstrip('\r\n\t ')
# Handle all three steps of parsing:
# 1: Quoting
# 2: Expansion (vars, ~, and glob.glob)
# 3: Splitting
if (not instr):
return []
parse_array = [[],[]]
parse_state = 0
# Stage 1: Process quotes
last_block = []
for i,c in enumerate(instr):
if (parse_state == 0):
# Base state, look for quotes that haven't been escaped
if (c == '\\'):
# Switch to special mode to escape the next character
last_block.append(i)
parse_state += 3
elif (c == '"'):
# Start double quoting
last_block.append(i)
parse_state = 1
elif (c == "'"):
# Start single quoting
last_block.append(i)
parse_state = 2
else:
parse_array[0].append(c)
parse_array[1].append(0)
elif (parse_state == 1):
if (c not in '$\\"'):
parse_array[0].append(c)
parse_array[1].append(1)
elif (c == '$'):
parse_array[0].append(c)
parse_array[1].append(0)
elif (c == '\\'):
last_block.append(i)
parse_state += 3
else:
last_block.pop()
parse_state = 0
elif (parse_state == 2):
if (c != "'"):
parse_array[0].append(c)
parse_array[1].append(1)
else:
last_block.pop()
parse_state = 0
elif (3 <= parse_state <= 4):
last_block.pop()
parse_array[0].append(c)
parse_array[1].append(parse_state + 0)
parse_state -= 3
if (1 <= parse_state <= 2):
raise SyntaxError("Unbalanced quotes at char %s: %s <--" % (last_block[-1],instr[:(last_block[-1]+1)]))
elif (parse_state == 3):
raise SyntaxError("Unfinished backslash escape at char %s: %s <--" % (last_block[-1],instr[:(last_block[-1]+1)]))
elif (parse_state == 4):
raise SyntaxError("Unfinished backslash escape within double quotes at char %s: %s <--" % (last_block[-1],instr[:(last_block[-1]+1)]))
# State 1.5: Rebuild the parse array, evaluating escaped characters
temp_array = [[],[]]
escapes = {'t': '\t', 'r': '\r', 'n': '\n'}
for i,c in enumerate(parse_array[0]):
if (3 <= parse_array[1][i] <= 4):
temp_array[0].append(escapes.get(c,c))
temp_array[1].append(1)
else:
temp_array[0].append(c)
temp_array[1].append(parse_array[1][i] + 0)
parse_array = temp_array
# Stage 2: Perform expansions
for i,c in enumerate(parse_array[0]):
if ((c == '$') and (parse_array[1][i] == 0)):
# Unquoted $ detected
remainder = ''.join(parse_array[0][i:])
for var_name in self.env_vars.keys():
if remainder.startswith(var_name):
# Found a variable that needs to be replaced
# Blow out the variable name
for j in range(i,len(var_name)+i):
parse_array[0][j] = ''
parse_array[1][j] = -1
# Insert the new value
parse_array[0][i] = self.env_vars[var_name]
parse_array[1][i] = 2
elif ((c == '~') and (parse_array[1][i] == 0)):
# Unquoted ~ detected, make sure it's dir-ish
if ((i == 0) and (len(parse_array[0]) == 1)):
# Tilde by itself
parse_array[0][i] = self.env_vars.get('$HOME', '/')
parse_array[1][i] = 2
elif ((i == 0) and ((parse_array[0][i+1] == '/') or ((parse_array[0][i+1] == ' ') and (parse_array[1][i+1] == 0)))):
# Tilde at start, followed by slash or non-escaped space
parse_array[0][i] = self.env_vars.get('$HOME', '/')
parse_array[1][i] = 2
elif ((len(parse_array[0]) == (i+1)) and ((parse_array[0][i-1] == ' ') and (parse_array[1][i-1] == 0))):
# Tilde at end, preceded by a non-escaped space
parse_array[0][i] = self.env_vars.get('$HOME', '/')
parse_array[1][i] = 2
elif (((parse_array[0][i-1] == ' ') and (parse_array[1][i-1] == 0)) and ((parse_array[0][i+1] == '/') or ((parse_array[0][i+1] == ' ') and (parse_array[1][i+1] == 0)))):
# Tilde not at start or end, preceded by a non-escaped space and followed by slash or non-escaped space
parse_array[0][i] = self.env_vars.get('$HOME', '/')
parse_array[1][i] = 2
# Stage 2.5: Rebuild the parse array, finalizing expansions
temp_array = [[],[]]
for i,c in enumerate(parse_array[0]):
if (parse_array[1][i] == 2):
for d in c:
temp_array[0].append(d)
temp_array[1].append(1)
elif (parse_array[1][i] >= 0):
temp_array[0].append(c)
temp_array[1].append(parse_array[1][i] + 0)
parse_array = temp_array
# Stage 2.7: Wildcard globbing
temp_groups = [[],[]]
split_mode = 0
for i,c in enumerate(parse_array[0]):
# Pre-split into words based on non-escaped whitespace
if (not ((c in ' \t\n\r') and (parse_array[1][i] == 0))):
if (split_mode == 0):
split_mode = 1
temp_groups[0].append([c])
temp_groups[1].append([0 + parse_array[1][i]])
else:
temp_groups[0][-1].append(c)
temp_groups[1][-1].append(parse_array[1][i])
else:
split_mode = 0
temp_groups[0].append([c])
temp_groups[1].append([0 + parse_array[1][i]])
temp_array = [[],[]]
seen_first = False
not_whitespace = False
for i,chunk in enumerate(temp_groups[0]):
# Iterate through words looking for unescaped glob characters
glob_chunk = False
for j,c in enumerate(chunk):
if ((c in '*[]?') and (temp_groups[1][i][j] == 0)):
# Found a chunk with unescaped glob character, but it's not the first chunk
if (seen_first):
glob_chunk = True
if (not seen_first):
if (not ((c in ' \t\n\r') and (temp_groups[1][i][j] == 0))):
not_whitespace = True
if (not_whitespace):
seen_first = True
not_whitespace = False
if (glob_chunk):
# Found a glob containing chunk
glob_str = ''.join(chunk)
matches = glob.glob(glob_str)
if (matches):
for match in matches:
for c in match:
temp_array[0].append(c)
temp_array[1].append(1)
temp_array[0].append(' ')
temp_array[1].append(0)
_ = temp_array[0].pop()
_ = temp_array[1].pop()
else:
for j,c in enumerate(chunk):
temp_array[0].append(c)
temp_array[1].append(temp_groups[1][i][j])
else:
for j,c in enumerate(chunk):
temp_array[0].append(c)
temp_array[1].append(temp_groups[1][i][j])
parse_array = temp_array
# Stage 2.9: Rebuild the parse array, escaping remaining non-whitespace
temp_array = [[],[]]
for i,c in enumerate(parse_array[0]):
if ((c not in ' \t\n\r') and (parse_array[1][i] == 0)):
temp_array[0].append(c)
temp_array[1].append(1)
else:
temp_array[0].append(c)
temp_array[1].append(parse_array[1][i] + 0)
parse_array = temp_array
# Stage 3: Splitting
split_mode = 0
final_value = []
for i,c in enumerate(parse_array[0]):
if (parse_array[1][i] == 1):
if (split_mode == 0):
split_mode = 1
final_value.append('' + c)
else:
final_value[-1] += c
else:
split_mode = 0
return final_value
class Shell(cmd.Cmd):
def __init__(self):
cmd.Cmd.__init__(self)
self._bash = BetterParser()
self._bash.env_vars['$HOME'] = os.path.expanduser('~/Documents')
self.did_quit = False
def bash(self, argstr):
try:
return self._bash.parse('. ' + argstr)[1:]
except SyntaxError, e:
print "Syntax Error: %s" % e
return None
def pprint(self, path):
if (path.startswith(self._bash.env_vars['$HOME'])):
return '~' + path.split(self._bash.env_vars['$HOME'],1)[-1]
return path
def do_pwd(self, line):
"""return working directory name"""
print self.pprint(os.getcwd())
def do_cd(self, line):
"""change the current directory to DIR"""
args = self.bash(line)
if args is None:
return
elif args and len(args) == 1:
try:
os.chdir(args[0])
except Exception:
print "cd: %s: No such directory" % line
elif len(args) > 1:
print "cd: Too many arguments"
else:
os.chdir(self._bash.env_vars['$HOME'])
def sizeof_fmt(self, num):
for x in ['bytes','KB','MB','GB']:
if num < 1024.0:
if (x == 'bytes'):
return "%s %s" % (num, x)
else:
return "%3.1f %s" % (num, x)
num /= 1024.0
return "%3.1f%s" % (num, 'TB')
def do_mkdir(self, line):
"""make a directory"""
args = self.bash(line)
if args is None:
return
elif (len(args) == 1):
target = args[0]
if os.path.exists(target):
print "mkdir: %s: File exists" % line
else:
try:
os.mkdir(target)
except Exception:
print "mkdir: %s: Unable to create" % line
else:
print "mkdir: Usage: mkdir directory_name"
def do_mv(self, line):
"""move files and directories"""
args = self.bash(line)
if args is None:
return
elif (not (len(args) >= 2)):
print "mv: Usage: mv src [..] dest"
else:
dest = args[-1]
files = args[0:-1]
if (len(files) > 1):
# Moving multiple files, destination must be an existing directory.
if (not os.path.isdir(dest)):
print "cp: %s: No such directory" % self.pprint(dest)
else:
full_dest = os.path.abspath(dest).rstrip('/') + '/'
for filef in files:
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
new_name = os.path.join(full_dest,file_name)
if (not os.path.exists(full_file)):
print "! Error: Skipped, missing -", self.pprint(filef)
continue
try:
os.rename(full_file,new_name)
except Exception:
print "mv: %s: Unable to move" % self.pprint(filef)
else:
# Moving a single file to a (pre-existing) directory or a file
filef = files[0]
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
full_dest = os.path.abspath(dest).rstrip('/')
if (os.path.isdir(full_dest)):
if (os.path.exists(full_file)):
try:
os.rename(full_file, full_dest + '/' + file_name)
except:
print "mv: %s: Unable to move" % self.pprint(filef)
else:
print "mv: %s: No such file" % self.pprint(filef)
else:
if (os.path.exists(full_file)):
try:
os.rename(full_file, full_dest)
except:
print "mv: %s: Unable to move" % self.pprint(filef)
else:
print "mv: %s: No such file" % self.pprint(filef)
def do_cp(self, line):
"""copy files and directories"""
args = self.bash(line)
if args is None:
return
elif (not (len(args) >= 2)):
print "cp: Usage: cp src [..] dest"
else:
if len(args) > 2:
files = args[:-1]
dest = args[-1]
else:
files = args[:1]
dest = args[-1]
if (len(files) > 1):
# Copying multiple files, destination must be an existing directory.
if (not os.path.isdir(dest)):
print "cp: %s: No such directory" % self.pprint(dest)
else:
full_dest = os.path.abspath(dest).rstrip('/') + '/'
for filef in files:
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
new_name = os.path.join(full_dest,file_name)
if (not os.path.exists(full_file)):
print "! Error: Skipped, missing -", self.pprint(filef)
continue
try:
if (os.path.isdir(full_file)):
shutil.copytree(full_file,new_name)
else:
shutil.copy(full_file,new_name)
except Exception:
print "cp: %s: Unable to copy" % self.pprint(filef)
else:
# Copying a single file to a (pre-existing) directory or a file
filef = files[0]
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
full_dest = os.path.abspath(dest).rstrip('/')
new_name = os.path.join(full_dest,file_name)
if (os.path.isdir(full_dest)):
# Destination is a directory already
if (os.path.exists(full_file)):
try:
if (os.path.isdir(full_file)):
shutil.copytree(full_file,new_name)
else:
shutil.copy(full_file,new_name)
except:
print "cp: %s: Unable to copy" % self.pprint(filef)
else:
print "cp: %s: No such file" % self.pprint(filef)
elif (os.path.exists(full_dest)):
# Destination is a file
if (os.path.exists(full_file)):
try:
shutil.copy(full_file,full_dest)
except:
print "cp: %s: Unable to copy" % self.pprint(filef)
else:
print "cp: %s: No such file" % self.pprint(filef)
else:
if (os.path.isdir(full_file)):
# Source is a directory, destination should become a directory
try:
shutil.copytree(full_file,full_dest)
except:
print "cp: %s: Unable to copy" % self.pprint(filef)
else:
# Source is a file, destination should become a file
try:
shutil.copy(full_file,full_dest)
except:
print "cp: %s: Unable to copy" % self.pprint(filef)
def do_rm(self, line):
"""remove one or more files/directories"""
args = self.bash(line)
if args is None:
return
elif (len(args) < 1):
print "rm: Usage: rm file_or_dir [...]"
else:
for filef in args:
full_file = os.path.abspath(filef).rstrip('/')
if not os.path.exists(filef):
print "! Skipping: Not found -", self.pprint(filef)
continue
if (os.path.isdir(full_file)):
try:
shutil.rmtree(full_file, True)
if (os.path.exists(full_file)):
print "rm: %s: Unable to remove" % self.pprint(filef)
except Exception:
print "rm: %s: Unable to remove" % self.pprint(filef)
else:
try:
os.remove(full_file)
except Exception:
print "rm: %s: Unable to remove" % self.pprint(filef)
def do_cat(self, line):
"""print file"""
args = self.bash(line)
if args is None:
return
elif (len(args) != 1):
print "cat: Usage: cat file"
else:
target = args[0]
if (not os.path.exists(target)):
print "cat: %s: No such file" % line
elif (os.path.isdir(target)):
print "cat: %s: Is a directory" % line
else:
try:
contents = ""
with open(target, 'r') as f:
contents = f.read()
print contents
print ""
except Exception:
print "cat: %s: Unable to access" % line
def do_ls(self, line):
"""list directory contents"""
files = self.bash(line)
if files is None:
return
elif (not files):
files = ['.']
files_for_path = dict()
for filef in files:
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
dir_name = os.path.dirname(full_file).rstrip('/')
if (not os.path.exists(full_file)):
print "! Error: Skipped, missing -", self.pprint(filef)
continue
if (os.path.isdir(full_file)):
# Need to add this as a key and all the files contained inside it
_dirs = files_for_path.get(full_file, set())
for new_file in os.listdir(full_file):
_dirs.add(full_file.rstrip('/') + '/' + new_file.rstrip('/'))
files_for_path[full_file] = _dirs
else:
_dirs = files_for_path.get(dir_name, set())
_dirs.add(full_file)
files_for_path[dir_name] = _dirs
# Iterate over the paths, in alphabetical order:
paths = sorted(files_for_path.keys())
cwd = os.getcwd().rstrip('/')
in_cwd = False
if (cwd in paths):
# Move cwd to the front, mark that it's present
paths.remove(cwd)
paths = [cwd] + paths
in_cwd = True
for i,path in enumerate(paths):
if (i > 0):
print "\n" + self.pprint(path) + "/:"
elif (not in_cwd):
print self.pprint(path) + "/:"
for filef in sorted(list(files_for_path[path])):
full_file = os.path.abspath(filef).rstrip('/')
file_name = os.path.basename(full_file)
if (os.path.isdir(full_file)):
print file_name + "/"
else:
print file_name + (" (%s)" % (self.sizeof_fmt(os.stat(full_file).st_size)))
def do_unzip(self, line):
"""unzip a zip archive"""
# filename with optional destination
args = self.bash(line)
if args is None:
return
elif not (1 <= len(args) <= 2):
print "unzip: Usage: unzip file [destination]"
else:
filename = os.path.abspath(args[0])
if not os.path.isfile(filename):
print "unzip: %s: No such file" % args[0]
else:
# PK magic marker check
f = open(filename)
try:
pk_check = f.read(2)
except Exception:
pk_check = ''
finally:
f.close()
if pk_check != 'PK':
print "unzip: %s: does not appear to be a zip file" % args[0]
else:
if (os.path.basename(filename).lower().endswith('.zip')):
altpath = os.path.splitext(os.path.basename(filename))[0]
else:
altpath = os.path.basename(filename) + '_unzipped'
altpath = os.path.join(os.path.dirname(filename), altpath)
location = (args[1:2] or [altpath])[0]
if (os.path.exists(location)) and not (os.path.isdir(location)):
print "unzip: %s: destination is not a directory" % location
return
elif not os.path.exists(location):
os.makedirs(location)
zipfp = open(filename, 'rb')
try:
zipf = zipfile.ZipFile(zipfp)
# check for a leading directory common to all files and remove it
dirnames = [os.path.join(os.path.dirname(x), '') for x in zipf.namelist()]
common_dir = os.path.commonprefix(dirnames or ['/'])
# Check to make sure there aren't 2 or more sub directories with the same prefix
if not common_dir.endswith('/'):
common_dir = os.path.join(os.path.dirname(common_dir), '')
for name in zipf.namelist():
data = zipf.read(name)
fn = name
if common_dir:
if fn.startswith(common_dir):
fn = fn.split(common_dir, 1)[-1]
elif fn.startswith('/' + common_dir):
fn = fn.split('/' + common_dir, 1)[-1]
fn = fn.lstrip('/')
fn = os.path.join(location, fn)
dirf = os.path.dirname(fn)
if not os.path.exists(dirf):
os.makedirs(dirf)
if fn.endswith('/'):
# A directory
if not os.path.exists(fn):
os.makedirs(fn)
else:
fp = open(fn, 'wb')
try:
fp.write(data)
finally:
fp.close()
except Exception:
zipfp.close()
print "unzip: %s: zip file is corrupt" % args[0]
return
finally:
zipfp.close()
def do_untar(self, line):
"""untar a tar archive"""
# filename with optional destination
args = self.bash(line)
if args is None:
return
elif not (1 <= len(args) <= 2):
print "untar: Usage: untar file [destination]"
else:
filename = os.path.abspath(args[0])
if not os.path.isfile(filename):
print "untar: %s: No such file" % args[0]
else:
# 'ustar' magic marker check
f = open(filename)
try:
f.seek(257)
ustar_check = f.read(5)
except Exception:
ustar_check = ''
finally:
f.close()
if ustar_check != 'ustar':
print "untar: %s: does not appear to be a tar file" % args[0]
else:
if (os.path.basename(filename).lower().endswith('.tar')):
altpath = os.path.splitext(os.path.basename(filename))[0]
else:
altpath = os.path.basename(filename) + '_untarred'
altpath = os.path.join(os.path.dirname(filename), altpath)
location = (args[1:2] or [altpath])[0]
if (os.path.exists(location)) and not (os.path.isdir(location)):
print "untar: %s: destination is not a directory" % location
return
elif not os.path.exists(location):
os.makedirs(location)
try:
tar = tarfile.open(filename, 'r')
# check for a leading directory common to all files and remove it
dirnames = [os.path.join(os.path.dirname(x.name), '') for x in tar.getmembers() if x.name != 'pax_global_header']
common_dir = os.path.commonprefix(dirnames or ['/'])
if not common_dir.endswith('/'):
common_dir = os.path.join(os.path.dirname(common_dir), '')
for member in tar.getmembers():
fn = member.name
if fn == 'pax_global_header':
continue
if common_dir:
if fn.startswith(common_dir):
fn = fn.split(common_dir, 1)[-1]
elif fn.startswith('/' + common_dir):
fn = fn.split('/' + common_dir, 1)[-1]
fn = fn.lstrip('/')
fn = os.path.join(location, fn)
dirf = os.path.dirname(fn)
if member.isdir():
# A directory
if not os.path.exists(fn):
os.makedirs(fn)
elif member.issym():
# skip symlinks
continue
else:
try:
fp = tar.extractfile(member)
except (KeyError, AttributeError):
# invalid member, not necessarily a bad tar file
continue
if not os.path.exists(dirf):
os.makedirs(dirf)
with open(fn, 'wb') as destfp:
shutil.copyfileobj(fp, destfp)
fp.close()
except Exception:
tar.close()
print "untar: %s: tar file is corrupt" % args[0]
return
finally:
tar.close()
def do_ungzip(self, line, gunzip=False):
"""ungzip a gzip archive"""
# filename with optional output filename
fname = 'ungzip'
if gunzip:
fname = 'gunzip'
args = self.bash(line)
if args is None:
return
elif not (1 <= len(args) <= 2):
print "%s: Usage: %s file [outfile]" % (fname, fname)
else:
filename = os.path.abspath(args[0])
if not os.path.isfile(filename):
print "%s: %s: No such file" % (fname,args[0])
else:
# '\x1f\x8b\x08' magic marker check
f = open(filename, 'rb')
try:
gz_check = f.read(3)
except Exception:
gz_check = ''
finally:
f.close()
if gz_check != '\x1f\x8b\x08':
print "%s: %s: does not appear to be a gzip file" % (fname,args[0])
else:
if (os.path.basename(filename).lower().endswith('.gz') or os.path.basename(filename).lower().endswith('.gzip')):
altpath = os.path.splitext(os.path.basename(filename))[0]
elif os.path.basename(filename).lower().endswith('.tgz'):
altpath = os.path.splitext(os.path.basename(filename))[0] + '.tar'
else:
altpath = os.path.basename(filename) + '_ungzipped'
altpath = os.path.join(os.path.dirname(filename), altpath)
location = (args[1:2] or [altpath])[0]
if os.path.exists(location):
print "%s: %s: destination already exists" % (fname,os.path.basename(location))
return
dirf = os.path.dirname(os.path.dirname(os.path.abspath(location)))
try:
if not os.path.exists(dirf):
os.makedirs(dirf)
with open(location, 'wb') as outfile:
with gzip.open(filename, 'rb') as gzfile:
outfile.write(gzfile.read())
except Exception:
print "%s: %s: gzip file is corrupt" % (fname, args[0])
def do_gunzip(self, line):
"""ungzip a gzip archive"""
self.do_ungzip(line, gunzip=True)
def do_quit(self,line):
self.did_quit = True
def do_q(self,line):
self.did_quit = True
def do_exit(self,line):
self.did_quit = True
def do_logout(self,line):
self.did_quit = True
def do_logoff(self,line):
self.did_quit = True
def postcmd(self,stop,line):
return self.did_quit
def main():
shell = Shell()
shell.prompt = '> '
shell.cmdloop()
if __name__ == '__main__':
main()
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