Na}{

File Content: `dbrecio.py`

"""
File-like objects that read from or write to a bsddb record.

This implements (nearly) all stdio methods.

f = DBRecIO(db, key, txn=None)
f.close()           # explicitly release resources held
flag = f.isatty()   # always false
pos = f.tell()      # get current position
f.seek(pos)         # set current position
f.seek(pos, mode)   # mode 0: absolute; 1: relative; 2: relative to EOF
buf = f.read()      # read until EOF
buf = f.read(n)     # read up to n bytes
f.truncate([size])  # truncate file at to at most size (default: current pos)
f.write(buf)        # write at current position
f.writelines(list)  # for line in list: f.write(line)

Notes:
- fileno() is left unimplemented so that code which uses it triggers
  an exception early.
- There's a simple test set (see end of this file) - not yet updated
  for DBRecIO.
- readline() is not implemented yet.


From:
    Itamar Shtull-Trauring <itamar@maxnm.com>
"""

import errno
import string

class DBRecIO:
    def __init__(self, db, key, txn=None):
        self.db = db
        self.key = key
        self.txn = txn
        self.len = None
        self.pos = 0
        self.closed = 0
        self.softspace = 0

    def close(self):
        if not self.closed:
            self.closed = 1
            del self.db, self.txn

    def isatty(self):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        return 0

    def seek(self, pos, mode = 0):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        if mode == 1:
            pos = pos + self.pos
        elif mode == 2:
            pos = pos + self.len
        self.pos = max(0, pos)

    def tell(self):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        return self.pos

    def read(self, n = -1):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        if n < 0:
            newpos = self.len
        else:
            newpos = min(self.pos+n, self.len)

        dlen = newpos - self.pos

        r = self.db.get(self.key, txn=self.txn, dlen=dlen, doff=self.pos)
        self.pos = newpos
        return r

    __fixme = """
    def readline(self, length=None):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        if self.buflist:
            self.buf = self.buf + string.joinfields(self.buflist, '')
            self.buflist = []
        i = string.find(self.buf, '\n', self.pos)
        if i < 0:
            newpos = self.len
        else:
            newpos = i+1
        if length is not None:
            if self.pos + length < newpos:
                newpos = self.pos + length
        r = self.buf[self.pos:newpos]
        self.pos = newpos
        return r

    def readlines(self, sizehint = 0):
        total = 0
        lines = []
        line = self.readline()
        while line:
            lines.append(line)
            total += len(line)
            if 0 < sizehint <= total:
                break
            line = self.readline()
        return lines
    """

    def truncate(self, size=None):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        if size is None:
            size = self.pos
        elif size < 0:
            raise IOError(errno.EINVAL,
                                      "Negative size not allowed")
        elif size < self.pos:
            self.pos = size
        self.db.put(self.key, "", txn=self.txn, dlen=self.len-size, doff=size)

    def write(self, s):
        if self.closed:
            raise ValueError, "I/O operation on closed file"
        if not s: return
        if self.pos > self.len:
            self.buflist.append('\0'*(self.pos - self.len))
            self.len = self.pos
        newpos = self.pos + len(s)
        self.db.put(self.key, s, txn=self.txn, dlen=len(s), doff=self.pos)
        self.pos = newpos

    def writelines(self, list):
        self.write(string.joinfields(list, ''))

    def flush(self):
        if self.closed:
            raise ValueError, "I/O operation on closed file"


"""
# A little test suite

def _test():
    import sys
    if sys.argv[1:]:
        file = sys.argv[1]
    else:
        file = '/etc/passwd'
    lines = open(file, 'r').readlines()
    text = open(file, 'r').read()
    f = StringIO()
    for line in lines[:-2]:
        f.write(line)
    f.writelines(lines[-2:])
    if f.getvalue() != text:
        raise RuntimeError, 'write failed'
    length = f.tell()
    print 'File length =', length
    f.seek(len(lines[0]))
    f.write(lines[1])
    f.seek(0)
    print 'First line =', repr(f.readline())
    here = f.tell()
    line = f.readline()
    print 'Second line =', repr(line)
    f.seek(-len(line), 1)
    line2 = f.read(len(line))
    if line != line2:
        raise RuntimeError, 'bad result after seek back'
    f.seek(len(line2), 1)
    list = f.readlines()
    line = list[-1]
    f.seek(f.tell() - len(line))
    line2 = f.read()
    if line != line2:
        raise RuntimeError, 'bad result after seek back from EOF'
    print 'Read', len(list), 'more lines'
    print 'File length =', f.tell()
    if f.tell() != length:
        raise RuntimeError, 'bad length'
    f.close()

if __name__ == '__main__':
    _test()
"""
Name	Size	Permission
__init__.py	15988 bytes	0644
__init__.pyc	12376 bytes	0644
db.py	2730 bytes	0644
db.pyc	590 bytes	0644
dbobj.py	11331 bytes	0644
dbobj.pyc	18609 bytes	0644
dbrecio.py	5308 bytes	0644
dbrecio.pyc	5277 bytes	0644
dbshelve.py	11558 bytes	0644
dbshelve.pyc	12918 bytes	0644
dbtables.py	30866 bytes	0644
dbtables.pyc	24410 bytes	0644
dbutils.py	2964 bytes	0644
dbutils.pyc	1623 bytes	0644
File Content: dbrecio.py

File Content: `dbrecio.py`
