The commit's purpose is laudable:
The only way for chardev drivers to communicate an error was to
return a NULL pointer, which resulted in an error message that
said _that_ something went wrong, but not _why_.
It attempts to achieve it by changing the interface to return 0/-errno
and update qemu_chr_open_opts() to use strerror() to display a more
helpful error message. Unfortunately, it has serious flaws:
1. Backends "socket" and "udp" return bogus error codes, because
qemu_chr_open_socket() and qemu_chr_open_udp() assume that
unix_listen_opts(), unix_connect_opts(), inet_listen_opts(),
inet_connect_opts() and inet_dgram_opts() fail with errno set
appropriately. That assumption is wrong, and the commit turns
unspecific error messages into misleading error messages. For
instance:
$ qemu-system-x86_64 -nodefaults -vnc :0 -chardev socket,id=bar,host=xxx
inet_connect: host and/or port not specified
chardev: opening backend "socket" failed: No such file or directory
ENOENT is what happens to be in my errno when the backend returns
-errno. Let's put ERANGE there just for giggles:
$ qemu-system-x86_64 -nodefaults -vnc :0 -chardev socket,id=bar,host=xxx -drive if=none,iops=99999999999999999999
inet_connect: host and/or port not specified
chardev: opening backend "socket" failed: Numerical result out of range
Worse: when errno happens to be zero, return -errno erroneously
signals success, and qemu_chr_new_from_opts() dies dereferencing
uninitialized chr. I observe this with "-serial unix:".
2. All qemu_chr_open_opts() knows about the error is an errno error
code. That's simply not enough for a decent message. For instance,
when inet_dgram() can't resolve the parameter host, which errno code
should it use? What if it can't resolve parameter localaddr?
Clue: many backends already report errors in their open methods.
Let's revert the flawed commit along with its dependencies, and fix up
the silent error paths instead.
This reverts commit 6e1db57b2a.
Conflicts:
console.c
hw/baum.c
qemu-char.c
This reverts commit aad04cd024.
The parts of commit db418a0a "Add stdio char device on windows" that
depend on the reverted change fixed up.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The only way for chardev drivers to communicate an error was to return a NULL
pointer, which resulted in an error message that said _that_ something went
wrong, but not _why_.
This patch changes the interface to return 0/-errno and updates
qemu_chr_open_opts to use strerror to display a more helpful error message.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This was done with:
sed -i 's/qemu_get_clock\>/qemu_get_clock_ns/' \
$(git grep -l 'qemu_get_clock\>' )
sed -i 's/qemu_new_timer\>/qemu_new_timer_ns/' \
$(git grep -l 'qemu_new_timer\>' )
after checking that get_clock and new_timer never occur twice
on the same line. There were no missed occurrences; however, even
if there had been, they would have been caught by the compiler.
There was exactly one false positive in qemu_run_timers:
- current_time = qemu_get_clock (clock);
+ current_time = qemu_get_clock_ns (clock);
which is of course not in this patch.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a destroy hook for the baum character device, to properly close the BrlAPI
connection.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
baum.c is using free() instead of qemu_free().
Fix it.
Signed-off-by: Jean-Christophe DUBOIS <jcd@tribudubois.net>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This function sends out the OPENED event to backends that
have drive the chardevs. The 'reset' is now a historical
artifact and we can now just call the function for what it
is.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The char event RESET is emitted when a char device is opened.
Give it a better name.
Patchworks-ID: 35287
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
SDL header files can be included in two different ways:
* like this: #include <SDL/SDL.h>
* like this: #include <SDL.h>
The 1st alternative is simple and works in many cases.
The 2nd alternative needs sdl-config to get the
correct compiler flags. It is the recommended way
to write SDL includes and standard for QEMU.
The patch fixes two non-standard SDL includes.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Include assert.h from qemu-common.h and remove other direct uses.
cpu-all.h still need to include it because of the dyngen-exec.h hacks
Signed-off-by: Paul Brook <paul@codesourcery.com>
Paolo Bonzini
Markus Armbruster
Anthony Liguori
Kevin Wolf
Samuel Thibault
Jean-Christophe DUBOIS
Amit Shah
Gerd Hoffmann
Juan Quintela
Stefan Weil
Blue Swirl
Paul Brook
aurel32
aliguori