diff options
Diffstat (limited to 'Lib/tarfile.py')
| -rw-r--r-- | Lib/tarfile.py | 87 |
1 files changed, 60 insertions, 27 deletions
diff --git a/Lib/tarfile.py b/Lib/tarfile.py index 29e12f0..f48b477 100644 --- a/Lib/tarfile.py +++ b/Lib/tarfile.py @@ -195,7 +195,7 @@ def nti(s): try: n = int(nts(s) or "0", 8) except ValueError: - raise HeaderError("invalid header") + raise InvalidHeaderError("invalid header") else: n = 0L for i in xrange(len(s) - 1): @@ -346,8 +346,23 @@ class StreamError(TarError): """Exception for unsupported operations on stream-like TarFiles.""" pass class HeaderError(TarError): + """Base exception for header errors.""" + pass +class EmptyHeaderError(HeaderError): + """Exception for empty headers.""" + pass +class TruncatedHeaderError(HeaderError): + """Exception for truncated headers.""" + pass +class EOFHeaderError(HeaderError): + """Exception for end of file headers.""" + pass +class InvalidHeaderError(HeaderError): """Exception for invalid headers.""" pass +class SubsequentHeaderError(HeaderError): + """Exception for missing and invalid extended headers.""" + pass #--------------------------- # internal stream interface @@ -1179,14 +1194,16 @@ class TarInfo(object): def frombuf(cls, buf): """Construct a TarInfo object from a 512 byte string buffer. """ + if len(buf) == 0: + raise EmptyHeaderError("empty header") if len(buf) != BLOCKSIZE: - raise HeaderError("truncated header") + raise TruncatedHeaderError("truncated header") if buf.count(NUL) == BLOCKSIZE: - raise HeaderError("empty header") + raise EOFHeaderError("end of file header") chksum = nti(buf[148:156]) if chksum not in calc_chksums(buf): - raise HeaderError("bad checksum") + raise InvalidHeaderError("bad checksum") obj = cls() obj.buf = buf @@ -1225,8 +1242,6 @@ class TarInfo(object): tarfile. """ buf = tarfile.fileobj.read(BLOCKSIZE) - if not buf: - return obj = cls.frombuf(buf) obj.offset = tarfile.fileobj.tell() - BLOCKSIZE return obj._proc_member(tarfile) @@ -1279,9 +1294,10 @@ class TarInfo(object): buf = tarfile.fileobj.read(self._block(self.size)) # Fetch the next header and process it. - next = self.fromtarfile(tarfile) - if next is None: - raise HeaderError("missing subsequent header") + try: + next = self.fromtarfile(tarfile) + except HeaderError: + raise SubsequentHeaderError("missing or bad subsequent header") # Patch the TarInfo object from the next header with # the longname information. @@ -1386,12 +1402,12 @@ class TarInfo(object): pos += length # Fetch the next header. - next = self.fromtarfile(tarfile) + try: + next = self.fromtarfile(tarfile) + except HeaderError: + raise SubsequentHeaderError("missing or bad subsequent header") if self.type in (XHDTYPE, SOLARIS_XHDTYPE): - if next is None: - raise HeaderError("missing subsequent header") - # Patch the TarInfo object with the extended header info. next._apply_pax_info(pax_headers, tarfile.encoding, tarfile.errors) next.offset = self.offset @@ -1565,12 +1581,16 @@ class TarFile(object): if self.mode == "a": # Move to the end of the archive, # before the first empty block. - self.firstmember = None while True: - if self.next() is None: - if self.offset > 0: - self.fileobj.seek(- BLOCKSIZE, 1) + self.fileobj.seek(self.offset) + try: + tarinfo = self.tarinfo.fromtarfile(self) + self.members.append(tarinfo) + except EOFHeaderError: + self.fileobj.seek(self.offset) break + except HeaderError, e: + raise ReadError(str(e)) if self.mode in "aw": self._loaded = True @@ -1735,7 +1755,7 @@ class TarFile(object): try: t = cls.taropen(name, mode, fileobj, **kwargs) - except IOError: + except (IOError, EOFError): raise ReadError("not a bzip2 file") t._extfileobj = False return t @@ -2307,24 +2327,37 @@ class TarFile(object): # Read the next block. self.fileobj.seek(self.offset) + tarinfo = None while True: try: tarinfo = self.tarinfo.fromtarfile(self) - if tarinfo is None: - return - self.members.append(tarinfo) - - except HeaderError, e: + except EOFHeaderError, e: if self.ignore_zeros: self._dbg(2, "0x%X: %s" % (self.offset, e)) self.offset += BLOCKSIZE continue - else: - if self.offset == 0: - raise ReadError(str(e)) - return None + except InvalidHeaderError, e: + if self.ignore_zeros: + self._dbg(2, "0x%X: %s" % (self.offset, e)) + self.offset += BLOCKSIZE + continue + elif self.offset == 0: + raise ReadError(str(e)) + except EmptyHeaderError: + if self.offset == 0: + raise ReadError("empty file") + except TruncatedHeaderError, e: + if self.offset == 0: + raise ReadError(str(e)) + except SubsequentHeaderError, e: + raise ReadError(str(e)) break + if tarinfo is not None: + self.members.append(tarinfo) + else: + self._loaded = True + return tarinfo #-------------------------------------------------------------------------- |