It turns out that our async write operation implementation is broken
on non-O_NONBLOCK pipes, because the default async write
implementation calls write() after poll() said there were some
space. However, the semantics of pipes is that unless O_NONBLOCK is set
then the write *will* block if the passed in write count is larger than
the available space.
This caused a deadlock in https://gitlab.gnome.org/GNOME/glib/-/issues/2182
due to the loop-back of the app stdout to the parent, but even without such
a deadlock it is a problem that we may block the mainloop at all.
In the particular case of g_subprocess_communicate() we have full
control of the pipes after starting the app, so it is safe to enable
O_NONBLOCK (i.e. we can ensure all the code using the fd after this can handle
non-blocking mode).
This fixes https://gitlab.gnome.org/GNOME/glib/-/issues/2182
This has almost the same semantics as WSAECONNRESET and for all
practical purposes is handled the same. The main difference is about
*who* reset the connection: the peer or something in the network.
For UDP sockets this happens when receiving packets and previously sent
packets returned an ICMP "Time(-to-live) expired" message. This is
similar to WSAECONNRESET, which on UDP sockets happens when receiving
packets and previously sent packets returned an ICMP "Port Unreachable"
message.
This is a step towards supporting `statx()`, which allows the set of
fields it returns to be specified by the caller. Currently, the existing
`stat()` and `fstat()` calls continue to be made, and there are no
behavioural changes — but the new wrapper functions will be extended in
future.
Helps: #1970
Don’t call `g_file_query_exists()` followed by `g_file_delete()`. Just
call `g_file_delete()` and check the error.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
Make `G_URI_FLAGS_PARSE_RELAXED` available instead, for the
implementations which need to handle user-provided or incorrect URIs.
The default should nudge people towards being compliant with RFC 3986.
This required also adding a new `G_URI_PARAMS_PARSE_RELAXED` flag, as
previously parsing param strings *always* used relaxed mode and there
was no way to control it. Now it defaults to using strict mode, and the
new flag allows for relaxed mode to be enabled if needed.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
Fixes: #2149
According to my reading of
https://tools.ietf.org/html/rfc3986#section-4, the only requirement for
a URI to be ‘absolute’ (actually, not a relative reference) is for the
scheme to be specified. A hostname doesn’t have to be specified: see any
of the options in the `hier-part` production in
https://tools.ietf.org/html/rfc3986#appendix-A which don’t include
`authority`.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
This reduces the possibility for overflow, and makes the code a little
more conventional to read.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
`guint8` is the conventional way in modern GLib APIs to represent ‘a byte
which could contain arbitrary binary’. `guchar` is not advised for that
(even though it’s equivalent) because it could be misread as `gchar`.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
This reduces the chance of the caller accidentally double-freeing or
use-after-free-ing something.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
Sometimes there are sensitive details in URI query components, so we
should provide the option for hiding them too.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
This brings its naming in line with the ‘generic’ error codes in other
error domains.
This is not an API break since `GUriError` hasn’t been in a release yet.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
RFC 3986, section 3 says:
> The scheme and path components are required, though the path may be
> empty (no characters). When authority is present, the path must
> either be empty or begin with a slash ("/") character. When
> authority is not present, the path cannot begin with two slash
> characters ("//"). These restrictions result in five different ABNF
> rules for a path (Section 3.3), only one of which will match any
> given URI reference.
(See https://tools.ietf.org/html/rfc3986#section-3.)
Given that those conditions are almost always going to be true, and that
typically the number and form of arguments passed to g_uri_join() will
be known at compile time, it would be unnecessarily awkward to add a
`GError` argument to g_uri_join() to detect these situations.
Instead, add precondition checks and document the restrictions.
Developers are responsible for ensuring their paths are in the right
format themselves.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
