Since all URLContexts have the same AVOptions, such AVOptions
will be applied on the outermost context only and removed from the
dict, while they probably make sense on all contexts.

This makes sure that rw_timeout gets propagated to the innermost
URLContext (to make sure it gets passed to the tcp protocol, when
opening a http connection for instance).

Alternatively, such matching options would be kept in the dict
and only removed after the ffurl_connect call.
Signed-off-by: Martin Storsjö <martin@martin.st>

Should make the default behaviour safer for careless callers that open
random untrusted files.

Bug-Id: CVE-2016-1897
Bug-Id: CVE-2016-1898

This way, the decisions about which protocols are available for use in
any given situations can be delegated to the caller.

It will be useful in the following commits.

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

This fixes a number of "assignment from incompatible pointer type" warnings.

Don't prefix them ffio_url, which is misleading, sounding too
much like the urlprotocol layer (like ffurl_*).
Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Martin Storsjö <martin@martin.st>

Trigger a refill if the seek action moves the pointer
at the end of the buffer.

Before this patch the read action following the seek would trigger
the refill, while write action would write outside the buffer.

In the Libav codebase few muxers seek forward outside of what
already has been written so it is quite unlikely to experience
the problem with the default buffer size.

CC: libav-stable@libav.org

Avoid a possible null pointer dereference.

CC: libav-stable@libav.org
Bug-Id: CID 1135769

Signed-off-by: Anton Khirnov <anton@khirnov.net>

This simplifies proper error handling in rtsp.c/rtspdec.c. When
broadcasting over RTSP in TCP mode, the AVIOContext is closed and
recreated for each sent packet, and if the recreation fails, we might
try to close a NULL buffer when freeing things at the end.

Previously, if recreating the buffer in rtspdec.c failed, this would
crash later due to trying to close a NULL buffer.
Signed-off-by: Martin Storsjö <martin@martin.st>

When av_reallocp fails, the associated variables that keep track of
the number of elements in the array (and in some cases, the
separate number of allocated elements) need to be reset.

Not all of these might technically be needed, but it's better to
reset them if in doubt, to make sure variables don't end up
conflicting.
Signed-off-by: Martin Storsjö <martin@martin.st>

Null buffers are useful for simulating writing to a real buffer
for the sake of measuring how many bytes are written.
Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Diego Biurrun <diego@biurrun.de>

This provides at least some protection against potential accidental
corruption of AVIO buffer workspace.
Signed-off-by: Martin Storsjö <martin@martin.st>

As long as there is enough contiguous data in the avio buffer,
just return a pointer to it instead of copying it to the caller
provided buffer.
Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Martin Storsjö <martin@martin.st>

This makes RTP custom IO work properly with pure read-only
AVIOContexts as well.
Signed-off-by: Martin Storsjö <martin@martin.st>

So far, aviocontexts are used either in pure-read or pure-write
mode - full read/write mode doesn't work well (and implementing it
is a much larger, not totally trivial change).

This patch allows using avio_read and ffio_read_partial on
read/write aviocontexts, where the read operations are passed
through directly unbuffered, while writes are buffered as usual.

This is enough to support the operations needed by packet based
data transfer like in udp/rtp, where aviocontext is the only
public API for hooking up custom IO.
Signed-off-by: Martin Storsjö <martin@martin.st>

This seemed to assume that one never used writing avio unless
muxers or networking was enabled.

This ifdef is a remnant since 8fa641f8.
Signed-off-by: Martin Storsjö <martin@martin.st>

This is consistent with stdio, and thus what people would naturally
expect.

Its behaviour in line with ffurl_close(NULL).

Fixes an invalid free() with ass in avi. The sample in bug 98 passes
parts of AVPacket.data as buffer for the AVIOContext. Since the packet
is quite large fill_buffer tries to reallocate the buffer before doing
nothing. Fixes bug 98.

The interrupt callback has to be passed in during opening (setting it
after opening isn't enough), since a blocking open couldn't be
interrupted otherwise.

Options are passed down to procotols and also need to be available
during open() in most cases.
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Not used anywhere yet, support for passing options from avio_open() will
follow.

Change all uses of these function to pass the relevant
callback on.

Signed-off-by: Anton Khirnov <anton@khirnov.net>

Make AVIO_FLAG_ access constants work as flags, and in particular fix
the behavior of functions (such as avio_check()) which expect them to
be flags rather than modes.

This breaks API.