Commit f22a28b8 authored by Eric Blake's avatar Eric Blake Committed by Markus Armbruster
Browse files

qapi: Add alias for ErrorClass 



The qapi enum ErrorClass is unusual that it uses 'CamelCase' names,
contrary to our documented convention of preferring 'lower-case'.
However, this enum is entrenched in the API; we cannot change
what strings QMP outputs.  Meanwhile, we want to simplify how
c_enum_const() is used to generate enum constants, by moving away
from the heuristics of camel_to_upper() to a more straightforward
c_name(N).upper() - but doing so will rename all of the ErrorClass
constants and cause churn to all client files, where the new names
are aesthetically less pleasing (ERROR_CLASS_DEVICENOTFOUND looks
like we can't make up our minds on whether to break between words).

So as always in computer science, solve the problem by some more
indirection: rename the qapi type to QapiErrorClass, and add a
new enum ErrorClass in error.h whose members are aliases of the
qapi type, but with the spelling expected elsewhere in the tree.
Then, when c_enum_const() changes the munging, we only have to
adjust the one alias spot.

Suggested by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-26-git-send-email-eblake@redhat.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
parent 86f4b687

include/qapi/error.h

+14 −0
Original line number Diff line number Diff line
@@ -90,6 +90,20 @@ 
 */

typedef struct Error Error;



/*

 * Overall category of an error.

 * Based on the qapi type QapiErrorClass, but reproduced here for nicer

 * enum names.

 */

typedef enum ErrorClass {

    ERROR_CLASS_GENERIC_ERROR = QAPI_ERROR_CLASS_GENERIC_ERROR,

    ERROR_CLASS_COMMAND_NOT_FOUND = QAPI_ERROR_CLASS_COMMAND_NOT_FOUND,

    ERROR_CLASS_DEVICE_ENCRYPTED = QAPI_ERROR_CLASS_DEVICE_ENCRYPTED,

    ERROR_CLASS_DEVICE_NOT_ACTIVE = QAPI_ERROR_CLASS_DEVICE_NOT_ACTIVE,

    ERROR_CLASS_DEVICE_NOT_FOUND = QAPI_ERROR_CLASS_DEVICE_NOT_FOUND,

    ERROR_CLASS_KVM_MISSING_CAP = QAPI_ERROR_CLASS_KVM_MISSING_CAP,

} ErrorClass;



/*

 * Get @err's human-readable error message.

 */

monitor.c

+1 −1
Original line number Diff line number Diff line
@@ -403,7 +403,7 @@ static QDict *build_qmp_error_dict(Error *err) 
    QObject *obj;



    obj = qobject_from_jsonf("{ 'error': { 'class': %s, 'desc': %s } }",

                             ErrorClass_lookup[error_get_class(err)],

                             QapiErrorClass_lookup[error_get_class(err)],

                             error_get_pretty(err));



    return qobject_to_qdict(obj);

qapi/common.json

+3 −2
Original line number Diff line number Diff line
@@ -3,7 +3,7 @@ 
# QAPI common definitions



##

# @ErrorClass

# @QapiErrorClass

#

# QEMU error classes

#
@@ -24,7 +24,8 @@ 
#

# Since: 1.2

##

{ 'enum': 'ErrorClass',

{ 'enum': 'QapiErrorClass',

  # Keep this in sync with ErrorClass in error.h

  'data': [ 'GenericError', 'CommandNotFound', 'DeviceEncrypted',

            'DeviceNotActive', 'DeviceNotFound', 'KVMMissingCap' ] }

qapi/qmp-dispatch.c

+1 −1
Original line number Diff line number Diff line
@@ -114,7 +114,7 @@ static QObject *do_qmp_dispatch(QObject *request, Error **errp) 
QObject *qmp_build_error_object(Error *err)

{

    return qobject_from_jsonf("{ 'class': %s, 'desc': %s }",

                              ErrorClass_lookup[error_get_class(err)],

                              QapiErrorClass_lookup[error_get_class(err)],

                              error_get_pretty(err));

}