diff options
| -rw-r--r-- | Lib/StringIO.py | 314 |
1 files changed, 163 insertions, 151 deletions
diff --git a/Lib/StringIO.py b/Lib/StringIO.py index 4bfd55f..98f190f 100644 --- a/Lib/StringIO.py +++ b/Lib/StringIO.py @@ -30,167 +30,179 @@ Notes: """ try: - from errno import EINVAL + from errno import EINVAL except ImportError: - EINVAL = 22 + EINVAL = 22 EMPTYSTRING = '' class StringIO: - def __init__(self, buf = ''): - self.buf = buf - self.len = len(buf) + def __init__(self, buf = ''): + self.buf = buf + self.len = len(buf) + self.buflist = [] + self.pos = 0 + self.closed = 0 + self.softspace = 0 + + def close(self): + if not self.closed: + self.closed = 1 + del self.buf, self.pos + + 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 self.buflist: + self.buf += EMPTYSTRING.join(self.buflist) + self.buflist = [] + if mode == 1: + pos += self.pos + elif mode == 2: + 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 self.buflist: + self.buf += EMPTYSTRING.join(self.buflist) + self.buflist = [] + if n < 0: + newpos = self.len + else: + newpos = min(self.pos+n, self.len) + r = self.buf[self.pos:newpos] + self.pos = newpos + return r + + def readline(self, length=None): + if self.closed: + raise ValueError, "I/O operation on closed file" + if self.buflist: + self.buf += EMPTYSTRING.join(self.buflist) + self.buflist = [] + i = self.buf.find('\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(EINVAL, "Negative size not allowed") + elif size < self.pos: + self.pos = size + self.buf = self.getvalue()[: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) + if self.pos < self.len: + if self.buflist: + self.buf += EMPTYSTRING.join(self.buflist) self.buflist = [] - self.pos = 0 - self.closed = 0 - self.softspace = 0 - def close(self): - if not self.closed: - self.closed = 1 - del self.buf, self.pos - 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 self.buflist: - self.buf += EMPTYSTRING.join(self.buflist) - self.buflist = [] - if mode == 1: - pos += self.pos - elif mode == 2: - 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 self.buflist: - self.buf += EMPTYSTRING.join(self.buflist) - self.buflist = [] - if n < 0: - newpos = self.len - else: - newpos = min(self.pos+n, self.len) - r = self.buf[self.pos:newpos] - self.pos = newpos - return r - def readline(self, length=None): - if self.closed: - raise ValueError, "I/O operation on closed file" - if self.buflist: - self.buf += EMPTYSTRING.join(self.buflist) - self.buflist = [] - i = self.buf.find('\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(EINVAL, "Negative size not allowed") - elif size < self.pos: - self.pos = size - self.buf = self.getvalue()[: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) - if self.pos < self.len: - if self.buflist: - self.buf += EMPTYSTRING.join(self.buflist) - self.buflist = [] - self.buflist = [self.buf[:self.pos], s, self.buf[newpos:]] - self.buf = '' - if newpos > self.len: - self.len = newpos - else: - self.buflist.append(s) - self.len = newpos - self.pos = newpos - def writelines(self, list): - self.write(EMPTYSTRING.join(list)) - def flush(self): - if self.closed: - raise ValueError, "I/O operation on closed file" - def getvalue(self): - if self.buflist: - self.buf += EMPTYSTRING.join(self.buflist) - self.buflist = [] - return self.buf + self.buflist = [self.buf[:self.pos], s, self.buf[newpos:]] + self.buf = '' + if newpos > self.len: + self.len = newpos + else: + self.buflist.append(s) + self.len = newpos + self.pos = newpos + + def writelines(self, list): + self.write(EMPTYSTRING.join(list)) + + def flush(self): + if self.closed: + raise ValueError, "I/O operation on closed file" + + def getvalue(self): + if self.buflist: + self.buf += EMPTYSTRING.join(self.buflist) + self.buflist = [] + return self.buf # 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 =', `f.readline()` - here = f.tell() - line = f.readline() - print 'Second line =', `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() + 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 =', `f.readline()` + here = f.tell() + line = f.readline() + print 'Second line =', `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() + test() |