Matthew Barnes noted this on IRC a few days ago. I just had this file
open for other reasons and decided to tweak the docs to make this trap
more clear.
https://bugzilla.gnome.org/show_bug.cgi?id=709301
There are some corner cases where using the sync version of read/write
in a thread could cause thread-safety issues. In these cases it's
possible to override the output stream's splice_async() function,
but for input streams one would need to do some acrobatics to
stay thread-safe. Alternatively, some implementations may not even
override their sync read/write functions.
This patch refactors the default splice_async() implementation to
call the sync read and write functions in a thread only when both
async versions are thread-based. When one or both are non-threaded,
it calls the virtual write_async() and read_async() functions of the
involved streams within the same thread.
https://bugzilla.gnome.org/show_bug.cgi?id=691581
Refactor g_output_stream_close_async() into itself and an internal
variant for potential use inside other operations (splice_async).
The internal version must be called between
g_output_stream_set_pending() and g_output_stream_clear_pending().
https://bugzilla.gnome.org/show_bug.cgi?id=691581
In implementing a better g_output_stream_splice_async() and possibly
other situtations it's helpful to know whether the output stream's
write function internally uses threads. If it and the input stream's
read async functions use threads, then the splice function could
spawn a single thread for better efficiency.
This patch adds a function to determine whether an output stream's
g_output_stream_write_async() function internally uses threads.
https://bugzilla.gnome.org/show_bug.cgi?id=691581
As it turns out, we have examples of internal functions called
type_name_get_private() in the wild (especially among older libraries),
so we need to use a name for the per-instance private data getter
function that hopefully won't conflict with anything.
Rather than doing a two step first-check-the-GAsyncResult-subtype-then-
check-the-tag, add a GAsyncResult-level method so that you can do them
both at once, simplifying the code for "short-circuit" async return
values where the vmethod never gets called.
https://bugzilla.gnome.org/show_bug.cgi?id=661767
Finish deprecating the "handle GSimpleAsyncResult errors in the
wrapper function" idiom (and protect against future GSimpleAsyncResult
deprecation warnings) by adding a "legacy" GAsyncResult method
to do it in those classes/methods where it had been traditionally
done.
(This applies only to wrapper methods; in cases where an _async
vmethod explicitly uses GSimpleAsyncResult, its corresponding _finish
vmethod still uses g_simple_async_result_propagate_error.)
https://bugzilla.gnome.org/show_bug.cgi?id=667375https://bugzilla.gnome.org/show_bug.cgi?id=661767
Originally, the standard idiom with GSimpleAsyncResult was to handle
all errors in the _finish wrapper function, so that vmethods only had
to deal with successful results. But this means that chaining up to a
parent _finish vmethod won't work correctly. Fix this by also checking
for errors in all the relevant vmethods. (We have to redundantly check
in both the vmethod and the wrapper to preserve compatibility.)
https://bugzilla.gnome.org/show_bug.cgi?id=667375https://bugzilla.gnome.org/show_bug.cgi?id=661767
Using a caller-supplied buffer for g_input_stream_read() doesn't
translate well to the semantics of many other languages, and using a
non-refcounted buffer for read_async() and write_async() makes it
impossible to manage the memory correctly currently in
garbage-collected languages.
Fix both of these issues by adding a new set of methods that work with
GBytes objects rather than plain buffers.
https://bugzilla.gnome.org/show_bug.cgi?id=671139
g_output_stream_write_async() was not initializing the newly-added
members of the WriteData structure, causing various problems.
Also, g_input_stream_read_async() was now leaking its cancellable. Fix
that as well.
https://bugzilla.gnome.org/show_bug.cgi?id=674612
If a GInputStream does not provide a read_async() implementation, but
does implement GPollableInputStream, then instead of doing
read-synchronously-in-a-thread, just use
g_pollable_input_stream_read_nonblocking() and
g_pollable_input_stream_create_source() to implement an async read in
the same thread. Similarly for GOutputStream.
Remove a bunch of existing read_async()/write_async() implementations
that are basically equivalent to the new fallback method.
https://bugzilla.gnome.org/show_bug.cgi?id=673997
After questioning the semantics of flush on IRC, it seemed necessary to
clarify what flushing is supposed to do. The Linux man page for fflush()
seemed to cover it perfectly, so I just copied it.
I did not add the "via the underlying write mechanism" part as that in
my opinion is not something subclasses should need to guarantee.
Ensure that the output/target stream in a g_output_stream_splice_async()
operation is marked as closed if G_OUTPUT_STREAM_SPLICE_CLOSE_TARGET is
passed to g_output_stream_splice_async(). This removes the possibility of
local FDs being closed twice because the stream's not marked as closed.
This is implemented by calling g_output_stream_close() from within
g_output_stream_splice_async() instead of calling the stream's close_fn()
directly.
Closes: bgo#659324
This patch guarantees that g_output_stream_write() can never fail with
G_IO_ERROR_WOULD_BLOCK. Without such a guarantee, we would need some
kind of GIOPollable interface or some way to get an event when the
stream is writable again. Which is mostly useless considering that
this method is asynchronous anyway.
Note: this patch just codifies existing behavior - GUnixOutputStream,
GSocketOutputStream and other implementations already work this way.
See also bug 626748 comment 5 for how the GDBus code relies on this
guarantee.
https://bugzilla.gnome.org/show_bug.cgi?id=627071
Signed-off-by: David Zeuthen <davidz@redhat.com>
2008-07-01 Cody Russell <bratsche@gnome.org>
* gio/gioenums.h:
* gio/giotypes.h:
Moved all relevant typedefs into these files.
* gio/*.[ch]:
Updated wrt added files.
Split types into separate file for easier maintainership. (#538564)
svn path=/trunk/; revision=7127
2008-06-16 Michael Natterer <mitch@imendio.com>
* *.c: chain up unconditionally in finalize() and dispose(). Also
don't dereference these function pointers when calling them since
that has no meaning at all.
svn path=/trunk/; revision=7048
