From: Marc-André Lureau <marcandre.lur...@redhat.com> Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com> Tested-by: John Snow <js...@redhat.com> --- docs/devel/qapi-code-gen.txt | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-)
diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt index edaaf7ec40..4a3fd02723 100644 --- a/docs/devel/qapi-code-gen.txt +++ b/docs/devel/qapi-code-gen.txt @@ -780,26 +780,31 @@ downstream command __com.redhat_drive-mirror. === Configuring the schema === Syntax: - COND = STRING - | [ STRING, ... ] + COND = CFG-ID + | [ COND, ... ] + | { 'all: [ COND, ... ] } + | { 'any: [ COND, ... ] } + | { 'not': COND } -All definitions take an optional 'if' member. Its value must be a -string or a list of strings. A string is shorthand for a list -containing just that string. The code generated for the definition -will then be guarded by #if STRING for each STRING in the COND list. + CFG-ID = STRING + +All definitions take an optional 'if' member. Its value must be a string, a list +of strings or an object with a single member 'all', 'any' or 'not'. A string is +shorthand for a list containing just that string. A list is a shorthand for a +'all'-member object. The C code generated for the definition will then be guarded +by an #if precessor expression generated from that condition: 'all': [COND, ...] +will generate '(COND && ...)', 'any': [COND, ...] '(COND || ...)', 'not': COND '!COND'. Example: a conditional struct { 'struct': 'IfStruct', 'data': { 'foo': 'int' }, - 'if': ['CONFIG_FOO', 'HAVE_BAR'] } + 'if': { 'all': [ 'CONFIG_FOO', 'HAVE_BAR' ] } } gets its generated code guarded like this: - #if defined(CONFIG_FOO) - #if defined(HAVE_BAR) + #if defined(CONFIG_FOO) && defined(HAVE_BAR) ... generated code ... - #endif /* defined(HAVE_BAR) */ - #endif /* defined(CONFIG_FOO) */ + #endif /* defined(HAVE_BAR) && defined(CONFIG_FOO) */ Individual members of complex types, commands arguments, and event-specific data can also be made conditional. This requires the -- 2.29.0