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-rw-r--r--Lib/StringIO.py314
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()