From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:48397) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TRTLx-00070V-Ia for qemu-devel@nongnu.org; Thu, 25 Oct 2012 15:44:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TRTLw-0003wE-15 for qemu-devel@nongnu.org; Thu, 25 Oct 2012 15:44:29 -0400 Received: from e28smtp02.in.ibm.com ([122.248.162.2]:59644) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TRTLv-0003sj-2m for qemu-devel@nongnu.org; Thu, 25 Oct 2012 15:44:27 -0400 Received: from /spool/local by e28smtp02.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 26 Oct 2012 01:13:56 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q9PJhrul9961806 for ; Fri, 26 Oct 2012 01:13:54 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q9Q1DitC032615 for ; Fri, 26 Oct 2012 12:13:44 +1100 Message-ID: <5089964E.3060207@linux.vnet.ibm.com> Date: Fri, 26 Oct 2012 03:43:10 +0800 From: Lei Li MIME-Version: 1.0 References: <1350838081-6351-1-git-send-email-lilei@linux.vnet.ibm.com> <1350838081-6351-6-git-send-email-lilei@linux.vnet.ibm.com> <20121022165928.65ef9602@doriath.home> <50879601.1090609@linux.vnet.ibm.com> <20121024105536.2bc9a9bf@doriath.home> In-Reply-To: <20121024105536.2bc9a9bf@doriath.home> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 5/5] HMP: Introduce console command List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Luiz Capitulino Cc: blauwirbel@gmail.com, aliguori@us.ibm.com, qemu-devel@nongnu.org On 10/24/2012 08:55 PM, Luiz Capitulino wrote: > On Wed, 24 Oct 2012 15:17:21 +0800 > Lei Li wrote: > >> On 10/23/2012 02:59 AM, Luiz Capitulino wrote: >>> On Mon, 22 Oct 2012 00:48:01 +0800 >>> Lei Li wrote: >>> >>>> Signed-off-by: Lei Li >>>> --- >>>> hmp-commands.hx | 23 +++++++++++++++++++++++ >>>> hmp.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++ >>>> hmp.h | 1 + >>>> monitor.c | 15 +++++++++++++++ >>>> monitor.h | 3 +++ >>>> 5 files changed, 95 insertions(+), 0 deletions(-) >>>> >>>> diff --git a/hmp-commands.hx b/hmp-commands.hx >>>> index 5f91428..f862a53 100644 >>>> --- a/hmp-commands.hx >>>> +++ b/hmp-commands.hx >>>> @@ -868,7 +868,30 @@ char device and return @var{size} of the data. >>>> that specifies behavior when the queue is full/empty. By default is >>>> 'drop'. Note that the 'block' option is not supported now. >>>> -b for 'block' option. None for 'drop' option. >>>> +ETEXI >>>> + >>>> + { >>>> + .name = "console", >>>> + .args_type = "chardev:s", >>>> + .params = "chardev", >>>> + .help = "Connect to the serial console from within the" >>>> + "monitor, allow to write data to memchardev" >>>> + "'chardev'. Exit from the console and return back" >>>> + "to monitor by typing 'ctrl-]'", >>>> + .mhandler.cmd = hmp_console, >>>> + }, >>>> >>>> +STEXI >>>> +@item console @var{device} >>>> +@findex console >>>> + >>>> +Connect to the serial console from within the monitor, allow to write data >>>> +to memchardev @var{chardev}. Exit from the console and return back to >>>> +monitor by typing 'ctrl-]'. >>>> +@example >>>> +(qemu) console foo >>>> +foo: data string... >>>> +@end example >>>> ETEXI >>>> >>>> { >>>> diff --git a/hmp.c b/hmp.c >>>> index fa858c4..bc245f4 100644 >>>> --- a/hmp.c >>>> +++ b/hmp.c >>>> @@ -1245,3 +1245,56 @@ void hmp_screen_dump(Monitor *mon, const QDict *qdict) >>>> qmp_screendump(filename, &err); >>>> hmp_handle_error(mon, &err); >>>> } >>>> + >>>> +enum escape_char >>>> +{ >>>> + ESCAPE_CHAR_CTRL_GS = 0x1d /* ctrl-] used for escape */ >>>> +}; >>>> + >>>> +static void hmp_read_console(Monitor *mon, const char *data, >>>> + void *opaque) >>>> +{ >>>> + CharDriverState *chr = opaque; >>>> + uint32_t size = strlen(data); >>>> + enum DataFormat format = DATA_FORMAT_UTF8; >>>> + enum CongestionControl control = CONGESTION_CONTROL_DROP; >>>> + enum escape_char console_escape = ESCAPE_CHAR_CTRL_GS; >>>> + >>>> + Error *err = NULL; >>>> + >>>> + if (*data == console_escape) { >>>> + monitor_resume(mon); >>>> + return; >>>> + } >>>> + >>>> + qmp_memchar_write(chr->label, size, data, 0, format, >>>> + 0, control, &err); >>>> + if (err) { >>>> + monitor_printf(mon, "%s\n", error_get_pretty(err)); >>>> + error_free(err); >>>> + return; >>>> + } >>> Shouldn't you also read from the device? >> The use-case for this console command is just allow the user to >> write data to each memchar device as in a signal terminal. Then >> type escape sequences to take you back to the monitor. So I don't >> think it is also need to read from the device in this command. >> >> BTW, we can read from the device by hmp_memchar_read. :) > And how is the console command better than the hmp_memchar_write one? > > Could you please give examples? Sure. The "console" command behaves like: (qemu) console foo foo: hello world (qemu) you can input data, then put enter or ctrl-] to return back to the monitor. The data input from console would be written to the CirMemCharDriver backend, which provide a more friendly and nice HMP command as Anthony suggested. > >>>> + >>>> + monitor_read_command(mon, 1); >>>> +} >>>> + >>>> +void hmp_console(Monitor *mon, const QDict *qdict) >>>> +{ >>>> + const char *device = qdict_get_str(qdict, "chardev"); >>>> + CharDriverState *chr; >>>> + Error *err = NULL; >>>> + >>>> + chr = qemu_chr_find(device); >>>> + >>>> + if (!chr) { >>>> + error_set(&err, QERR_DEVICE_NOT_FOUND, device); >>>> + goto out; >>>> + } >>> No need to do this here as the QMP command will do it too. >>> >> I think we should do this check here, otherwise would >> cause core dump when 'console' to a chardev that does not >> exist. Wepass parameterchr->label by qmp_memchar_write() >> in the handler hmp_read_console. > Do you need the chr object? Why don't you just pass 'device' to > monitor_read_console()? Yes, we need 'device' and 'chr' both here. 'device' pass to monitor_read_console for the friendly prompt. 'chr' pass to handler hmp_read_console, the reason did not pass 'device' directly to it is the limitation of argument for the handler hmp_read_console. Also it's better to give the prompt before the user enter the input console if the device not found, the use-case as I post above. >>>> + >>>> + if (monitor_read_console(mon, device, hmp_read_console, chr) < 0) { >>>> + monitor_printf(mon, "Connect to console %s failed\n", device); >>>> + } >>>> + >>>> +out: >>>> + hmp_handle_error(mon, &err); >>>> +} >>>> diff --git a/hmp.h b/hmp.h >>>> index a5a0cfe..5b54a79 100644 >>>> --- a/hmp.h >>>> +++ b/hmp.h >>>> @@ -77,5 +77,6 @@ void hmp_getfd(Monitor *mon, const QDict *qdict); >>>> void hmp_closefd(Monitor *mon, const QDict *qdict); >>>> void hmp_send_key(Monitor *mon, const QDict *qdict); >>>> void hmp_screen_dump(Monitor *mon, const QDict *qdict); >>>> +void hmp_console(Monitor *mon, const QDict *qdict); >>>> >>>> #endif >>>> diff --git a/monitor.c b/monitor.c >>>> index 131b325..453c084 100644 >>>> --- a/monitor.c >>>> +++ b/monitor.c >>>> @@ -256,6 +256,21 @@ int monitor_read_password(Monitor *mon, ReadLineFunc *readline_func, >>>> } >>>> } >>>> >>>> +int monitor_read_console(Monitor *mon, const char *device, >>>> + ReadLineFunc *readline_func, void *opaque) >>>> +{ >>>> + char prompt[60]; >>>> + >>>> + if (!mon->rs) { >>>> + return -1; >>>> + } >>>> + >>>> + snprintf(prompt, sizeof(prompt), "%s: ", device); >>>> + readline_start(mon->rs, prompt, 0, readline_func, opaque); >>>> + >>>> + return 0; >>>> +} >>>> + >>>> void monitor_flush(Monitor *mon) >>>> { >>>> if (mon && mon->outbuf_index != 0 && !mon->mux_out) { >>>> diff --git a/monitor.h b/monitor.h >>>> index b6e7d95..735bd1b 100644 >>>> --- a/monitor.h >>>> +++ b/monitor.h >>>> @@ -86,6 +86,9 @@ ReadLineState *monitor_get_rs(Monitor *mon); >>>> int monitor_read_password(Monitor *mon, ReadLineFunc *readline_func, >>>> void *opaque); >>>> >>>> +int monitor_read_console(Monitor *mon, const char *device, >>>> + ReadLineFunc *readline_func, void *opaque); >>>> + >>>> int qmp_qom_set(Monitor *mon, const QDict *qdict, QObject **ret); >>>> >>>> int qmp_qom_get(Monitor *mon, const QDict *qdict, QObject **ret); >> > -- Lei