Commit Graph

130 Commits

Author SHA1 Message Date
Pavel Hrdina
43b01ef2d6 replace use of gnulib snprintf by g_snprintf
Glib implementation follows the ISO C99 standard so it's safe to replace
the gnulib implementation.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2019-11-15 15:07:40 +01:00
Jonathon Jongsma
95f5ac9ae5 Add API to change qemu agent response timeout
Some layered products such as oVirt have requested a way to avoid being
blocked by guest agent commands when querying a loaded vm. For example,
many guest agent commands are polled periodically to monitor changes,
and rather than blocking the calling process, they'd prefer to simply
time out when an agent query is taking too long.

This patch adds a way for the user to specify a custom agent timeout
that is applied to all agent commands.

One special case to note here is the 'guest-sync' command. 'guest-sync'
is issued internally prior to calling any other command. (For example,
when libvirt wants to call 'guest-get-fsinfo', we first call
'guest-sync' and then call 'guest-get-fsinfo').

Previously, the 'guest-sync' command used a 5-second timeout
(VIR_DOMAIN_QEMU_AGENT_COMMAND_DEFAULT), whereas the actual command that
followed always blocked indefinitely
(VIR_DOMAIN_QEMU_AGENT_COMMAND_BLOCK). As part of this patch, if a
custom timeout is specified that is shorter than
5 seconds,  this new timeout is also used for 'guest-sync'. If there is
no custom timeout or if the custom timeout is longer than 5 seconds, we
will continue to use the 5-second timeout.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-11-14 19:10:01 +01:00
Michal Privoznik
d4e5b98330 qemu: Use g_strdup_printf() instead of virAsprintf()
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-11-12 16:15:58 +01:00
Ján Tomko
ce36e33c10 qemu: use g_strdup instead of VIR_STRDUP
Replace all occurrences of
  if (VIR_STRDUP(a, b) < 0)
     /* effectively dead code */
with:
  a = g_strdup(b);

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-21 12:51:57 +02:00
Ján Tomko
72a1bb8e4c qemu: use g_steal_pointer instead of VIR_STEAL_PTR
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-16 15:59:42 +02:00
Ján Tomko
45678bd70a Use g_autoptr instead of VIR_AUTOPTR
Since commit 44e7f02915
    util: rewrite auto cleanup macros to use glib's equivalent

VIR_AUTOPTR aliases to g_autoptr. Replace all of its use by the GLib
macro version.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-16 12:06:43 +02:00
Ján Tomko
67e72053c1 Use G_N_ELEMENTS instead of ARRAY_CARDINALITY
Prefer the GLib version of the macro.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-15 16:14:19 +02:00
Ján Tomko
426f396198 use G_GNUC_NULL_TERMINATED instead of ATTRIBUTE_SENTINEL
Prefer G_GNUC_NULL_TERMINATED which was introduced in GLib 2.8.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-15 11:25:22 +02:00
Daniel P. Berrangé
6c748c8e2d util: use glib base64 encoding/decoding APIs
Replace use of the gnulib base64 module with glib's own base64 API family.

Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-10-14 10:54:42 +01:00
Jonathon Jongsma
be9d259ebc qemu: Validate arg in qemuAgentErrorComandUnsupported()
Coverity noted that 'reply' can be NULL after calling
qemuAgentCommand().  Avoid dereferencing reply in
qemuAgentErrorComandUnsupported() in that case.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
2019-08-30 17:23:03 -04:00
Jonathon Jongsma
1b380b89ff qemu: agent: fix potential leak in qemuAgentGetFSInfo()
On error paths, info_ret could potentially leak. Make sure it's freed.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-08-29 16:29:11 +02:00
Jonathon Jongsma
a931486a97 qemu: guestinfo: handle unsupported agent commands
When we're collecting guest information, older agents may not support
all agent commands. In the case where the user requested all info
types (i.e. types == 0), ignore unsupported command errors and gather as
much information as possible. If the agent command failed for some other
reason, or if the user explciitly requested a specific info type (i.e.
types != 0), abort on the first error.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-08-29 12:03:23 +02:00
Jonathon Jongsma
a68ed9fc42 qemu: add helper for getting full FSInfo
This function adds the complete filesystem information returned by the
qemu agent to an array of typed parameters with field names intended to
to be returned by virDomainGetGuestInfo()

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-08-26 17:27:40 +02:00
Jonathon Jongsma
ff89403050 qemu: add support for new fields in FSInfo
Since version 3.0, qemu has returned disk usage statistics in
guest-get-fsinfo. And since 3.1, it has returned information about the
disk serial number and device node of disks that are targeted by the
filesystem.

Unfortunately, the public API virDomainGetFSInfo() returns the
filesystem info using a virDomainFSInfo struct, and due to API/ABI
guarantees it cannot be extended. So this new information cannot
easily be added to the public API. However, it is possible to add this
new filesystem information to a new virDomainGetGuestInfo() API which
will be based on typed parameters and is thus more extensible.

In order to support these two use cases, I added an internal struct
which the agent code uses to return all of the new data fields. This
internal struct can be converted to the public struct at a cost of some
extra memory allocation.

In a following commit, this additional information will be used within
virDomainGetGuestInfo().

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-08-26 17:27:40 +02:00
Jonathon Jongsma
b11f485382 qemu: add helper for querying timezone info
This function queries timezone information within the guest and adds
the information to an array of typed parameters with field names
intended to be returned to virDomainGetGuestInfo()

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-08-26 17:27:40 +02:00
Jonathon Jongsma
d5b5a890dd qemu: add helper function for querying OS info
This function queries the guest operating system information and adds
the returned information to an array of typed parameters with field
names intended to be returned in virDomainGetGuestInfo().

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-08-26 17:27:40 +02:00
Jonathon Jongsma
1c8113f9c8 qemu: add helper for getting guest users
This function fetches the list of logged-in users from the qemu agent
and adds them to a list of typed parameters so that they can be used
internally in libvirt.

Also add some basic tests for the function.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2019-08-26 17:27:40 +02:00
Peter Krempa
285c5f28c4 util: Move enum convertors into virenum.(c|h)
virutil.(c|h) is a very gross collection of random code. Remove the enum
handlers from there so we can limit the scope where virtutil.h is used.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-10 09:12:04 +02:00
Cole Robinson
af36f8a641 Require a semicolon for VIR_ONCE_GLOBAL_INIT calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>). VIR_ONCE_GLOBAL_INIT is almost
exclusively called without an ending semicolon, but let's
standardize on using one like the other macros.

Add a dummy struct definition at the end of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Cole Robinson
6a4d938dd3 Require a semicolon for VIR_ENUM_IMPL calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_IMPL calls.

Move the verify() statement to the end of the macro and drop
the semicolon, so the compiler will require callers to add a
semicolon.

While we are touching these call sites, standardize on putting
the closing parenth on its own line, as discussed here:
https://www.redhat.com/archives/libvir-list/2019-January/msg00750.html

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Ján Tomko
7cfd1fbb13 qemu: require reply from guest agent in qemuAgentGetInterfaces
Since its introduction in commit 0977b8aa07 (released in v1.2.14)
qemuAgentGetInterfaces calls qemuAgentCommand with needReply=false,
which allows qemuAgentCommand to return 0 even when it did not get
any reply from the agent.

Set needReply to true, since we dereference it right after.

This can be hit if libvirt is waiting for an event from the agent
(e.g. shutdown) and the agent cannot reply in time (e.g. due to
the guest being shut down), as reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=1663051

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
2019-01-10 12:09:48 +01:00
Andrea Bolognani
5c7bfc6b53 src: Fix a few unmarked_diagnostics issues
These were not caught by our current regular expressions
but will be caught by the improved ones we're about to
introduce, so fix them ahead of time.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-08 17:18:31 +01:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Wang Yechao
bba16ff111 qemu: agent: Avoid agentError when closing the QEMU agent
The commit 89563efc02 fix the
monitor error when closing the QEMU monitor. The QEMU agent
has a problem similar to QEMU monitor. So fix the QEMU agent
with the same method.

Signed-off-by: Wang Yechao <wang.yechao255@zte.com.cn>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-11-15 13:51:02 -05:00
Erik Skultety
5165ff0971 src: More cleanup of some system headers already contained in internal.h
All of the ones being removed are pulled in by internal.h. The only
exception is sanlock which expects the application to include <stdint.h>
before sanlock's headers, because sanlock prototypes use fixed width
int, but they don't include stdint.h themselves, so we have to leave
that one in place.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-20 10:16:39 +02:00
John Ferlan
9ed175fbc2 qemu: Remove duplicated qemuAgentCheckError
Commit 5b3492fadb moved qemuAgentCheckError calls into
qemuAgentCommand for various reasons; however, subsequent
commit 0977b8aa0 adding a new command made call again
So let's just remove the duplicitous call from
qemuAgentGetInterfaces.

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-11 10:32:01 -04:00
John Ferlan
2cfc000f70 qemu: Remove duplicated qemuAgentCheckError
Commit 5b3492fadb moved qemuAgentCheckError calls into
qemuAgentCommand for various reasons; however, subsequent
commit b1aa91e14 restored the call. So let's just remove
the duplicitous call from qemuAgentSetVCPUsCommand.

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-11 10:31:36 -04:00
Julio Faracco
792113b8b8 qemu: unlink the error report from VIR_STRDUP.
The function to retrieve the file system info using QEMU-GA is using
some conditionals to retrieve the info. This is wrong because the error
of some conditionals will be raised if VIR_STRDUP return errors and not
if some problem occurred with JSON.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-09-05 13:13:41 -04:00
Julio Faracco
597bba39ec qemu: implementing qemuAgentGetHostname() function.
This commit implements the function qemuAgentGetHostname() that uses
the QEMU guest agent command 'guest-get-host-name' to retrieve the
guest hostname of virtual machine running the QEMU-GA.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-09-05 13:13:37 -04:00
Andrea Bolognani
6c0d0210cb src: Make virStr*cpy*() functions return an int
Currently, the functions return a pointer to the
destination buffer on success or NULL on failure.

Not only does this kind of error handling look quite
alien in the context of libvirt, where most functions
return zero on success and a negative int on failure,
but it's also somewhat pointless because unless there's
been a failure the returned pointer will be the same
one passed in by the user, thus offering no additional
value.

Change the functions so that they return an int
instead.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2018-07-23 14:27:30 +02:00
ramyelkest
2b6667abbf all: Replace virGetLastError with virGetLastErrorCode where we can
Replace instances where we previously called virGetLastError just to
either get the code or to check if an error exists with
virGetLastErrorCode to avoid a validity pre-check.

Signed-off-by: Ramy Elkest <ramyelkest@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-06-05 18:44:05 +02:00
Daniel P. Berrangé
fc06debd0c qemu: remove pointless connect retry logic in agent
When the agent code was first introduced back in

  commit c160ce3316
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Wed Oct 5 18:31:54 2011 +0100

    QEMU guest agent support

there was code that would loop and retry the connection when opening
the agent socket. At this time, the only thing done in between the
opening of the monitor socket & opening of the agent socket was a
call to set the monitor capabilities. This was a no-op on non-QMP
versions, so in theory there could be a race which let us connect
to the monitor while the agent socket was still not created by QEMU.

In the modern world, however, we long ago mandated the use of QMP
for managing QEMU, so we're guaranteed to have a set capabilities
QMP call. Once we've seen a reply to this, we're guaranteed that
QEMU has fully initialized all backends and is in its event loop.

We can thus be sure the QEMU agent socket is present and don't need
to retry connections to it, even without having the chardev FD passing
feature.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-06-05 17:30:57 +01:00
John Ferlan
4a3d6ed5ee util: Clean up consumers of virJSONValueArraySize
Rather than have virJSONValueArraySize return a -1 when the input
is not an array and then splat an error message, let's check for
an array before calling and then change the return to be a size_t
instead of ssize_t.

That means using the helper virJSONValueIsArray as well as using a
more generic error message such as "Malformed <something> array".
In some cases we can remove stack variables and when we cannot,
those variables should be size_t not ssize_t. Alter a few references
of if (!value) to be if (value == 0) instead as well.

Some callers can already assume an array is being worked on based
on the previous call, so there's less to do.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-05-10 14:59:15 -04:00
Martin Kletzander
5b912664c6 qemu/: Remove spaces after casts
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-05-03 22:31:37 +02:00
Michal Privoznik
10f94828ea virobject: Introduce VIR_CLASS_NEW() macro
So far we are repeating the following lines over and over:

  if (!(virSomeObjectClass = virClassNew(virClassForObject(),
                             "virSomeObject",
                             sizeof(virSomeObject),
                             virSomeObjectDispose)))
      return -1;

While this works, it is impossible to do some checking. Firstly,
the class name (the 2nd argument) doesn't match the name in the
code in all cases (the 3rd argument). Secondly, the current style
is needlessly verbose. This commit turns example into following:

  if (!(VIR_CLASS_NEW(virSomeObject,
                      virClassForObject)))
      return -1;

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-04-18 10:04:55 +02:00
Peter Krempa
0f0ad1116c json: Replace access to virJSONValue->type by virJSONValueGetType
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2018-04-03 13:34:33 +02:00
Peter Krempa
91813b8783 qemu: agent: Avoid unnecessary JSON object type check
Use virJSONValueObjectGetArray instead of virJSONValueObjectGet so that
it's not necessary to check whether it's an array.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2018-04-03 13:34:33 +02:00
Peter Krempa
ea520f6b67 util: json: Fix freeing of objects appended to virJSONValue
It was not possible to determine whether virJSONValueObjectAddVArgs and
the functions using it would consume a virJSONValue or not when used
with the 'a' or 'A' modifier depending on when the loop failed.

Fix this by passing in a pointer to the pointer so that it can be
cleared once it's successfully consumed and the callers don't have to
second-guess leaving a chance of leaking or double freeing the value
depending on the ordering.

Fix all callers to pass a double pointer too.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2018-04-03 13:34:33 +02:00
Daniel P. Berrangé
fbf31e1a4c qemu: avoid denial of service reading from QEMU guest agent (CVE-2018-1064)
We read from the agent until seeing a \r\n pair to indicate a completed
reply or event. To avoid memory denial-of-service though, we must have a
size limit on amount of data we buffer. 10 MB is large enough that it
ought to cope with normal agent replies, and small enough that we're not
consuming unreasonable mem.

This is identical to the flaw we had reading from the QEMU monitor
as CVE-2018-5748, so rather embarrassing that we forgot to fix
the agent code at the same time.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-14 12:16:42 +00:00
Chen Hanxiao
60a95e5242 qemu: don't leak in qemuGetDHCPInterfaces when failing to alloc
We forgot to free alloced mem when failed to
dup ifname or macaddr.

Also use VIR_STEAL_PTR to simplify codes.

Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2018-02-12 07:57:26 +01:00
Yuri Chornoivan
5efa7f2a4b Fix minor typos 2017-04-24 14:40:00 +02:00
Nikolay Shirokovskiy
cdd6819318 qemu: agent: take monitor lock in qemuAgentNotifyEvent
qemuAgentNotifyEvent accesses monitor structure and is called on qemu
reset/shutdown/suspend events under domain lock. Other monitor
functions on the other hand take monitor lock and don't hold domain lock.
Thus it is possible to have risky simultaneous access to the structure
from 2 threads. Let's take monitor lock here to make access exclusive.
2016-12-12 17:14:11 -05:00
Nikolay Shirokovskiy
3ab9652a86 qemu: agent: fix uninitialized var case in qemuAgentGetFSInfo
In case of 0 filesystems *info is not set while according
to virDomainGetFSInfo contract user should call free on it even
in case of 0 filesystems. Thus we need to properly set
it. NULL will be enough as free eats NULLs ok.
2016-12-12 17:14:11 -05:00
Michal Privoznik
c2a5a4e7ea virstring: Unify string list function names
We have couple of functions that operate over NULL terminated
lits of strings. However, our naming sucks:

virStringJoin
virStringFreeList
virStringFreeListCount
virStringArrayHasString
virStringGetFirstWithPrefix

We can do better:

virStringListJoin
virStringListFree
virStringListFreeCount
virStringListHasString
virStringListGetFirstWithPrefix

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-11-25 13:54:05 +01:00
Nikolay Shirokovskiy
6bff9c03c9 qemu: agent: give better error messages whe agent monitor is down
We can receive NULL as sync reply in two situations. First
is garbage sync reply and this situation is handled by
resending sync message. Second is different cases
of rebooting guest, destroing domain etc and we can
give more meaningful error message. Actually we have
this error message in qemuAgentCommand already which checks
for the same sitatuion. AFAIK case with mon->running
is just to be safe on adding some future(?) cases of
returning NULL reply.
2016-09-20 16:27:58 +02:00
Nikolay Shirokovskiy
3f90a1aac0 qemu: agent: reissue sync on garbage sync reply
We can easily handle receiving garbage on sync. We don't
have to make client deal with this situation. We just
need to resend sync command but this time garbage is
not be possible.
2016-09-20 16:27:58 +02:00
Nikolay Shirokovskiy
5e5019bf78 qemu: agent: skip outdated sync replies
When we wait for sync reply we can receive delayed
reply to syncs or commands that were sent erlier. We can
safely skip them until we receive sync reply with correct id.
There is no much sense report this situation to client.
Actually with a bit of "luck" if we involve client into
this the play can go on forever: send sync 0, receive
sync reply -1, send sync 1, receive reply 0 ...
2016-09-20 16:27:58 +02:00
Nikolay Shirokovskiy
832d48d790 qemu: agent: ignore garbage while waiting for sync reply
After sync is sent we can receive garbare and this is not error.
Consider next regular case:

1. libvirtd sends sync
2. qga sends partial sync reply and die
3. libvirtd sends sync
4. qga sends sync reply
5. libvirtd receives garbage
  (half of first reply and second reply together)

We should handle this situation as it is recoverable.
Next sync can succeed. Let's report reply is NULL,
it will be converted to the VIR_ERR_AGENT_UNSYNCED
which signals client to retry.
2016-09-20 16:27:58 +02:00
Nikolay Shirokovskiy
4fd25421e3 qemu: agent: ignore delayed reply when unsynced
Errors in qemuAgentIOProcessLine stop agent IO processing just
like any regular IO error, however some of current errors
that this functions spawns are false positives. Consider
next case for example:

1. send sync (unsynced state)
2. receive sync reply (sync established)
3. command send, but timeout occured (unsynced state)
4. receive command reply

Last IO triggers error because current code ignores
only delayed syncs when unsynced

We should not treat any delayed reply as error in unsynced
state. Until client and qga are not in sync delayed reply to any
command is possible. msg == NULL is the exact criterion
that we are not in sync.
2016-09-20 16:27:58 +02:00
Chen Hanxiao
4c886408c0 qemu_agent|monitor: use different log on hangup event
Both qemu monitor and agent print the same
log on HUANGUP event, which would be confusing
when reading libvirtd log.

This patch will give a different log message to them.

Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-19 13:06:03 +02:00