The read_istream_loose function loops on inflating a chunk of data
from an mmap'd loose object. We end the loop when we run out
of space in our output buffer, or if we see a zlib error.
We need to treat Z_BUF_ERROR specially, though, as it is not
fatal; it is just zlib's way of telling us that we need to
either feed it more input or give it more output space. It
is perfectly normal for us to hit this when we are at the
end of our buffer.
However, we may also get Z_BUF_ERROR because we have run out
of input. In a well-formed object, this should not happen,
because we have fed the whole mmap'd contents to zlib. But
if the object is truncated or corrupt, we will loop forever,
never giving zlib any more data, but continuing to ask it to
inflate.
We can fix this by considering it an error when zlib returns
Z_BUF_ERROR but we still have output space left (which means
it must want more input, which we know is a truncation
error). It would not be sufficient to just check whether
zlib had consumed all the input at the start of the loop, as
it might still want to generate output from what is in its
internal state.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The filter istream pulls data from an "upstream" stream,
running it through a filter function. However, we did not
properly notice when the upstream filter yielded an error,
and just returned what we had read. Instead, we should
propagate the error.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We call read_istream, but never check its return value for
errors. This can lead to us looping infinitely, as we just
keep trying to write "-1" bytes (and we do not notice the
error, as we simply check that write_in_full reports the
same number of bytes we fed it, which of course is also -1).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is because all other places do "xx > big_file_threshold"
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Allow any kind of buffer to be fed to read_istream() without an explicit
cast by making it's buf argument a void pointer. It's about arbitrary
data, not only characters.
Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The static function in entry.c takes a cache entry and streams its blob
contents to a file in the working tree. Refactor the logic to a new API
function stream_blob_to_fd() that takes an object name and an open file
descriptor, so that it can be reused by other callers.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Kirill Smelkov noticed that post-1.7.6 "git checkout"
started leaking tons of memory. The streaming_write_entry
function properly calls close_istream(), but that function
did not actually free() the allocated git_istream struct.
The git_istream struct is totally opaque to calling code,
and must be heap-allocated by open_istream. Therefore it's
not appropriate for callers to have to free it.
This patch makes close_istream() into "close and de-allocate
all associated resources". We could add a new "free_istream"
call, but there's not much point in letting callers inspect
the istream after close. And this patch's semantics make us
match fopen/fclose, which is well-known and understood.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* jc/zlib-wrap:
zlib: allow feeding more than 4GB in one go
zlib: zlib can only process 4GB at a time
zlib: wrap deflateBound() too
zlib: wrap deflate side of the API
zlib: wrap inflateInit2 used to accept only for gzip format
zlib: wrap remaining calls to direct inflate/inflateEnd
zlib wrapper: refactor error message formatter
Conflicts:
sha1_file.c
Some filters may need to buffer the input and look-ahead inside it
to decide what to output, and they may consume more than zero bytes
of input and still not produce any output. After feeding all the
input, pass NULL as input as keep calling stream_filter() to let
such filters know there is no more input coming, and it is time for
them to produce the remaining output based on the buffered input.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This introduces an API to plug custom filters to an input stream.
The caller gets get_stream_filter("path") to obtain an appropriate
filter for the path, and then uses it when opening an input stream
via open_istream(). After that, the caller can read from the stream
with read_istream(), and close it with close_istream(), just like an
unfiltered stream.
This only adds a "null" filter that is a pass-thru filter, but later
changes can add LF-to-CRLF and other filters, and the callers of the
streaming API do not have to change.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Given an object name, use open_istream() to get a git_istream handle
that you can read_istream() from as if you are using read(2) to read
the contents of the object, and close it with close_istream() when
you are done.
Currently, we do not do anything fancy--it just calls read_sha1_file()
and keeps the contents in memory as a whole, and carve it out as you
request with read_istream().
Signed-off-by: Junio C Hamano <gitster@pobox.com>
