I've typed error_report("%s", error_get_pretty(ERR)) too many times
already, and I've fixed too many instances of qerror_report_err(ERR)
to error_report("%s", error_get_pretty(ERR)) as well.  Capture the
pattern in a convenience function.

Since it's almost invariably followed by error_free(), stuff that into
the convenience function as well.

The next patch will put it to use.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

Makes it a bit clear how the interdependencies work.

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

This reverts commit d32934c8.

The original implementation before this patch makes abortive error
messages much more friendly. The underlying bug that required this
change is now fixed. Revert.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>

Use fprintf(stderr instead. This removes dependency of libqemuutil.a
on the monitor.

We can further justify this change, in that this code path should only
trigger under a fatal error condition. fprintf-stderr is probably the
appropriate medium as under a fatal error conidition the monitor itself
may be down and out for the count. So assertion failure messages should
go lowest common denominator - straight to stderr.

Fixes the build as reported by Kevin Wolf. Issue debugged and change
suggested by Luiz Capitulino. Issue introduced by
5d24ee70.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>

Add a special Error * that can be passed to error handling APIs to
signal that any errors are fatal and should abort QEMU. There are two
advantages to this:

- allows for brevity when wishing to assert success of Error **
  accepting APIs. No need for this pattern:
        Error * local_err = NULL;
        api_call(foo, bar, &local_err);
        assert_no_error(local_err);
  This also removes the need for _nofail variants of APIs with
  asserting call sites now reduced to 1LOC.
- SIGABRT happens from within the offending API. When a fatal error
  occurs in an API call (when the caller is asserting sucess) failure
  often means the API itself is broken. With the abort happening in the
  API call now, the stack frames into the call are available at debug
  time. In the assert_no_error scheme the abort happens after the fact.

The exact semantic is that when an error is raised, if the argument
Error ** matches &error_abort, then the abort occurs immediately. The
error messaged is reported.

For error_propagate, if the destination error is &error_abort, then
the abort happens at propagation time.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

There may be calls to error_setg() and especially error_setg_errno()
which blindly (and until now wrongly) assume these functions not to
clobber errno (e.g., they pass errno to error_setg_errno() and return
-errno afterwards). Instead of trying to find and fix all of these
constructs, just make sure error_setg() and error_setg_errno() indeed do
not clobber errno.
Suggested-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

These functions help maintaining homogeneous formatting of error messages
with Windows error code and description (generated by
g_win32_error_message()).
Signed-off-by: NTomoki Sekiyama <tomoki.sekiyama@hds.com>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Acked-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

These functions help maintaining homogeneous formatting of error
messages that include strerror values.
Acked-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Used to store error information, but it's unused now.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

This commit changes all QERR_ macros to contain a human message (ie.
the desc string found in qerr_table[]) instead of a json dictionary
in string format.

Before this commit, error_set() and qerror_report() would receive
a json dictionary in string format and build a qobject from it. Now,
both function receive a human message instead and the qobject is
not built anymore.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

error_get_qobject() is unused since last commit, error_set_qobject()
has never been used. Also drops error_int.h.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

Besides being unused, they operate on the current error format,
which is going to be replaced soon.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

The new argument is added to functions qerror_report() and error_set().
It's stored in Error and QError. qerror_report_err() is also updated to
take care of it.

The QERR_ macros are changed to contain a place holder value for the
new argument, so that the value is used on all current calls to
qerror_report() and error_set() (and also to initialize qerror_table[]).

Next commit will update the QERR_ macros with a proper ErrorClass
value.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

Today, the error message is only constructed when it's used. This commit
changes that to construct the error message when the error object is
built (ie. when the error is reported).

This simplifies the Error object.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

Simplifies current and future users.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

Don't overwrite / leak previously set errors.
Make traversal cope with missing mandatory sub-structs.
Don't try to end a container that could not be started.

v1->v2:
- unchanged

v2->v3:
- instead of examining, assert that we never overwrite errors with
  error_set()
- allow visitors to set a NULL struct pointer successfully, so traversal
  of incomplete objects can continue
- check for a NULL "obj" before accessing "(*obj)->has_XXX" (this is not a
  typo, "obj != NULL" implies "*obj != NULL" here)
- fix start_struct / end_struct balance for unions as well
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NLaszlo Ersek <lersek@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>

It is invalid to return a value from a function
returning void.

[C99 6.8.6.4 says "A return statement with an expression shall not
appear in a function whose return type is void" but gcc 4.6.3 with QEMU
compile flags does not complain.  It's still worth fixing this.  Stefan]
Signed-off-by: NAmos Kong <akong@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>

Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

Previous commits dropped most qobjects usage from qemu modules
(now they are a low level interface used by the QAPI). However,
some modules still include the qemu-objects.h header file.

This commit drops qemu-objects.h from some of those modules
and includes qjson.h instead, which is what they actually need.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

Reported-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

qemu_malloc/qemu_free no longer exist after this commit.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The declaration of function error_set() should use macro GCC_FMT_ATTR
instead of gcc's format printf attribute.

For w32/w64, both declarations are different and GCC_FMT_ATTR is needed.
Compilation for w64 even failed with the original code because mingw64
defines a macro for printf.

GCC_FMT_ATTR requires qemu-common.h, so add it in error.c
(it's also included by error_int.h but too late).

Remove assert.h which is included by qemu-common.h.

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>

New error-handling framework that allows for exception-like error
propagation.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>