qemu/backends/msmouse.c

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/*
* QEMU Microsoft serial mouse emulation
*
* Copyright (c) 2008 Lubomir Rintel
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdlib.h>
#include "qemu-common.h"
#include "sysemu/char.h"
#include "ui/console.h"
#define MSMOUSE_LO6(n) ((n) & 0x3f)
#define MSMOUSE_HI2(n) (((n) & 0xc0) >> 6)
static void msmouse_event(void *opaque,
int dx, int dy, int dz, int buttons_state)
{
CharDriverState *chr = (CharDriverState *)opaque;
unsigned char bytes[4] = { 0x40, 0x00, 0x00, 0x00 };
/* Movement deltas */
bytes[0] |= (MSMOUSE_HI2(dy) << 2) | MSMOUSE_HI2(dx);
bytes[1] |= MSMOUSE_LO6(dx);
bytes[2] |= MSMOUSE_LO6(dy);
/* Buttons */
bytes[0] |= (buttons_state & 0x01 ? 0x20 : 0x00);
bytes[0] |= (buttons_state & 0x02 ? 0x10 : 0x00);
bytes[3] |= (buttons_state & 0x04 ? 0x20 : 0x00);
/* We always send the packet of, so that we do not have to keep track
of previous state of the middle button. This can potentially confuse
some very old drivers for two button mice though. */
qemu_chr_be_write(chr, bytes, 4);
}
static int msmouse_chr_write (struct CharDriverState *s, const uint8_t *buf, int len)
{
/* Ignore writes to mouse port */
return len;
}
static void msmouse_chr_close (struct CharDriverState *chr)
{
g_free (chr);
}
CharDriverState *qemu_chr_open_msmouse(void)
{
CharDriverState *chr;
chr = qemu_chr_alloc();
chr->chr_write = msmouse_chr_write;
chr->chr_close = msmouse_chr_close;
qemu-char: don't issue CHR_EVENT_OPEN in a BH When CHR_EVENT_OPENED was initially added, it was CHR_EVENT_RESET, and it was issued as a bottom-half: 86e94dea5b740dad65446c857f6959eae43e0ba6 Which we basically used to print out a greeting/prompt for the monitor. AFAICT the only reason this was ever done in a BH was because in some cases we'd modify the chr_write handler for a new chardev backend *after* the site where we issued the reset (see: 86e94d:qemu_chr_open_stdio()) At some point this event was renamed to CHR_EVENT_OPENED, and we've maintained the use of this BH ever since. However, due to 9f939df955a4152aad69a19a77e0898631bb2c18, we schedule the BH via g_idle_add(), which is causing events to sometimes be delivered after we've already begun processing data from backends, leading to: known bugs: QMP: session negotation resets with OPENED event, in some cases this is causing new sessions to get sporadically reset potential bugs: hw/usb/redirect.c: can_read handler checks for dev->parser != NULL, which may be true if CLOSED BH has not been executed yet. In the past, OPENED quiesced outstanding CLOSED events prior to us reading client data. If it's delayed, our check may allow reads to occur even though we haven't processed the OPENED event yet, and when we do finally get the OPENED event, our state may get reset. qtest.c: can begin session before OPENED event is processed, leading to a spurious reset of the system and irq_levels gdbstub.c: may start a gdb session prior to the machine being paused To fix these, let's just drop the BH. Since the initial reasoning for using it still applies to an extent, work around that by deferring the delivery of CHR_EVENT_OPENED until after the chardevs have been fully initialized, toward the end of qmp_chardev_add() (or some cases, qemu_chr_new_from_opts()). This defers delivery long enough that we can be assured a CharDriverState is fully initialized before CHR_EVENT_OPENED is sent. Also, rather than requiring each chardev to do an explicit open, do it automatically, and allow the small few who don't desire such behavior to suppress the OPENED-on-init behavior by setting a 'explicit_be_open' flag. We additionally add missing OPENED events for stdio backends on w32, which were previously not being issued, causing us to not recieve the banner and initial prompts for qmp/hmp. Reported-by: Stefan Priebe <s.priebe@profihost.ag> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Message-id: 1370636393-21044-1-git-send-email-mdroth@linux.vnet.ibm.com Cc: qemu-stable@nongnu.org Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-08 00:19:53 +04:00
chr->explicit_be_open = true;
qemu_add_mouse_event_handler(msmouse_event, chr, 0, "QEMU Microsoft Mouse");
Revert "qemu-char: Print strerror message on failure" and deps 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 6e1db57b2ac9025c2443c665a0d9e78748637b26. Conflicts: console.c hw/baum.c qemu-char.c This reverts commit aad04cd024f0c59f0b96f032cde2e24eb3abba6d. 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>
2012-02-07 18:09:08 +04:00
return chr;
}
static void register_types(void)
{
register_char_driver_qapi("msmouse", CHARDEV_BACKEND_KIND_MSMOUSE, NULL);
}
type_init(register_types);