qga: conditionalize schema for commands requiring libudev

Rather than creating stubs for every command that just return
QERR_UNSUPPORTED, use 'if' conditions in the schema to fully
exclude generation of the filesystem trimming commands on POSIX
platforms lacking required APIs.

The command will be rejected at QMP dispatch time instead,
avoiding reimplementing rejection by blocking the stub commands.
This changes the error message for affected commands from

    {"class": "CommandNotFound", "desc": "Command FOO has been disabled"}

to

    {"class": "CommandNotFound", "desc": "The command FOO has not been found"}

This has the additional benefit that the QGA protocol reference
now documents what conditions enable use of the command.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-ID: <20240712132459.3974109-16-berrange@redhat.com>
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>

diff --git a/qga/commands-linux.c b/qga/commands-linux.c
index 73b13fbaf65c6ca6b0fb1cc0d3b00afa631b804d..89bdcded011e502f81b0890312738e44cf0d4599 100644 (file)
--- a/qga/commands-linux.c
+++ b/qga/commands-linux.c
@@ -1049,14 +1049,6 @@ GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
     return ret;
 }
 
-#else
-
-GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
-{
-    error_setg(errp, QERR_UNSUPPORTED);
-    return NULL;
-}
-
 #endif
 
 /* Return a list of the disk device(s)' info which @mount lies on */

diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json
index 21c65d180630f04beb5985d67d718cbabe2da7cc..cf1ad42519b89410158d4130fc238af30c26a5ed 100644 (file)
--- a/qga/qapi-schema.json
+++ b/qga/qapi-schema.json
@@ -986,7 +986,7 @@
            'media-errors-hi': 'uint64',
            'number-of-error-log-entries-lo': 'uint64',
            'number-of-error-log-entries-hi': 'uint64' },
-  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LINUX' ] } }
+  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LIBUDEV' ] } }
 
 ##
 # @GuestDiskSmart:
@@ -1001,7 +1001,7 @@
   'base': { 'type': 'GuestDiskBusType' },
   'discriminator': 'type',
   'data': { 'nvme': 'GuestNVMeSmart' },
-  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LINUX' ] } }
+  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LIBUDEV' ] } }
 
 ##
 # @GuestDiskInfo:
@@ -1027,7 +1027,7 @@
   'data': {'name': 'str', 'partition': 'bool', '*dependencies': ['str'],
            '*address': 'GuestDiskAddress', '*alias': 'str',
            '*smart': 'GuestDiskSmart'},
-  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LINUX' ] } }
+  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LIBUDEV' ] } }
 
 ##
 # @guest-get-disks:
@@ -1041,7 +1041,7 @@
 ##
 { 'command': 'guest-get-disks',
   'returns': ['GuestDiskInfo'],
-  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LINUX' ] } }
+  'if': { 'any': [ 'CONFIG_WIN32', 'CONFIG_LIBUDEV' ] } }
 
 ##
 # @GuestFilesystemInfo: