+"""Helper functions and classes for bup."""
import sys, os, pwd, subprocess, errno, socket, select, mmap, stat, re
from bup import _version
buf = buf[sz:]
def log(s):
+ """Print a log message to stderr."""
sys.stdout.flush()
_hard_write(sys.stderr.fileno(), s)
def mkdirp(d):
+ """Recursively create directories on path 'd'.
+
+ Unlike os.makedirs(), it doesn't raise an exception if the last element of
+ the path already exists.
+ """
try:
os.makedirs(d)
except OSError, e:
def next(it):
+ """Get the next item from an iterator, None if we reached the end."""
try:
return it.next()
except StopIteration:
return None
-
-
+
+
def unlink(f):
+ """Delete a file at path 'f' if it currently exists.
+
+ Unlike os.unlink(), does not throw an exception if the file didn't already
+ exist.
+ """
try:
os.unlink(f)
except OSError, e:
def readpipe(argv):
+ """Run a subprocess and return its output."""
p = subprocess.Popen(argv, stdout=subprocess.PIPE)
r = p.stdout.read()
p.wait()
return r
-# FIXME: this function isn't very generic, because it splits the filename
-# in an odd way and depends on a terminating '/' to indicate directories.
-# But it's used in a couple of places, so let's put it here.
-def pathsplit(p):
- l = p.split('/')
- l = [i+'/' for i in l[:-1]] + l[-1:]
- if l[-1] == '':
- l.pop() # extra blank caused by terminating '/'
- return l
-
-
-# like os.path.realpath, but doesn't follow a symlink for the last element.
-# (ie. if 'p' itself is itself a symlink, this one won't follow it)
def realpath(p):
+ """Get the absolute path of a file.
+
+ Behaves like os.path.realpath, but doesn't follow a symlink for the last
+ element. (ie. if 'p' itself is a symlink, this one won't follow it, but it
+ will follow symlinks in p's directory)
+ """
try:
st = os.lstat(p)
except OSError:
_username = None
def username():
+ """Get the user's login name."""
global _username
if not _username:
uid = os.getuid()
_userfullname = None
def userfullname():
+ """Get the user's full name."""
global _userfullname
if not _userfullname:
uid = os.getuid()
_hostname = None
def hostname():
+ """Get the FQDN of this machine."""
global _hostname
if not _hostname:
_hostname = socket.getfqdn()
pass
class Conn:
+ """A helper class for bup's client-server protocol."""
def __init__(self, inp, outp):
self.inp = inp
self.outp = outp
def read(self, size):
+ """Read 'size' bytes from input stream."""
self.outp.flush()
return self.inp.read(size)
def readline(self):
+ """Read from input stream until a newline is found."""
self.outp.flush()
return self.inp.readline()
def write(self, data):
+ """Write 'data' to output stream."""
#log('%d writing: %d bytes\n' % (os.getpid(), len(data)))
self.outp.write(data)
def has_input(self):
+ """Return true if input stream is readable."""
[rl, wl, xl] = select.select([self.inp.fileno()], [], [], 0)
if rl:
assert(rl[0] == self.inp.fileno())
return None
def ok(self):
+ """Indicate end of output from last sent command."""
self.write('\nok\n')
def error(self, s):
+ """Indicate server error to the client."""
s = re.sub(r'\s+', ' ', str(s))
self.write('\nerror %s\n' % s)
raise Exception('server exited unexpectedly; see errors above')
def drain_and_check_ok(self):
+ """Remove all data for the current command from input stream."""
def onempty(rl):
pass
return self._check_ok(onempty)
def check_ok(self):
+ """Verify that server action completed successfully."""
def onempty(rl):
raise Exception('expected "ok", got %r' % rl)
return self._check_ok(onempty)
def linereader(f):
+ """Generate a list of input lines from 'f' without terminating newlines."""
while 1:
line = f.readline()
if not line:
def chunkyreader(f, count = None):
+ """Generate a list of chunks of data read from 'f'.
+
+ If count is None, read until EOF is reached.
+
+ If count is a positive integer, read 'count' bytes from 'f'. If EOF is
+ reached while reading, raise IOError.
+ """
if count != None:
while count > 0:
b = f.read(min(count, 65536))
def slashappend(s):
+ """Append "/" to 's' if it doesn't aleady end in "/"."""
if s and not s.endswith('/'):
return s + '/'
else:
def mmap_read(f, sz = 0):
+ """Create a read-only memory mapped region on file 'f'.
+
+ If sz is 0, the region will cover the entire file.
+ """
return _mmap_do(f, sz, mmap.MAP_PRIVATE, mmap.PROT_READ)
def mmap_readwrite(f, sz = 0):
+ """Create a read-write memory mapped region on file 'f'.
+
+ If sz is 0, the region will cover the entire file.
+ """
return _mmap_do(f, sz, mmap.MAP_SHARED, mmap.PROT_READ|mmap.PROT_WRITE)
def parse_num(s):
+ """Parse data size information into a float number.
+
+ Here are some examples of conversions:
+ 199.2k means 203981 bytes
+ 1GB means 1073741824 bytes
+ 2.1 tb means 2199023255552 bytes
+ """
g = re.match(r'([-+\d.e]+)\s*(\w*)', str(s))
if not g:
raise ValueError("can't parse %r as a number" % s)
raise ValueError("invalid unit %r in number %r" % (unit, s))
return int(num*mult)
-
-# count the number of elements in an iterator (consumes the iterator)
+
def count(l):
+ """Count the number of elements in an iterator. (consumes the iterator)"""
return reduce(lambda x,y: x+1, l)
def atoi(s):
+ """Convert the string 's' to an integer. Return 0 if s is not a number."""
try:
return int(s or '0')
except ValueError:
saved_errors = []
def add_error(e):
+ """Append an error message to the list of saved errors.
+
+ Once processing is able to stop and output the errors, the saved errors are
+ accessible in the module variable helpers.saved_errors.
+ """
saved_errors.append(e)
log('%-70s\n' % e)
istty = os.isatty(2) or atoi(os.environ.get('BUP_FORCE_TTY'))
def progress(s):
+ """Calls log(s) if stderr is a TTY. Does nothing otherwise."""
if istty:
log(s)
def handle_ctrl_c():
+ """Replace the default exception handler for KeyboardInterrupt (Ctrl-C).
+
+ The new exception handler will make sure that bup will exit without an ugly
+ stacktrace when Ctrl-C is hit.
+ """
oldhook = sys.excepthook
def newhook(exctype, value, traceback):
if exctype == KeyboardInterrupt:
def columnate(l, prefix):
+ """Format elements of 'l' in columns with 'prefix' leading each line.
+
+ The number of columns is determined automatically based on the string
+ lengths.
+ """
l = l[:]
clen = max(len(s) for s in l)
ncols = (78 - len(prefix)) / (clen + 2)
def version_date():
+ """Format bup's version date string for output."""
return _version.DATE.split(' ')[0]
def version_commit():
+ """Get the commit hash of bup's current version."""
return _version.COMMIT
def version_tag():
+ """Format bup's version tag (the official version number).
+
+ When generated from a commit other than one pointed to with a tag, the
+ returned string will be "unknown-" followed by the first seven positions of
+ the commit hash.
+ """
names = _version.NAMES.strip()
assert(names[0] == '(')
assert(names[-1] == ')')
for n in l:
if n.startswith('tag: bup-'):
return n[9:]
- return 'unknown-%s' % _version.COMMIT[:7]
\ No newline at end of file
+ return 'unknown-%s' % _version.COMMIT[:7]
projects / bup.git / commitdiff