diff options
Diffstat (limited to 'docs')
-rw-r--r-- | docs/qapi-code-gen.txt | 43 |
1 files changed, 30 insertions, 13 deletions
diff --git a/docs/qapi-code-gen.txt b/docs/qapi-code-gen.txt index 9514d936ad..4b64ee7364 100644 --- a/docs/qapi-code-gen.txt +++ b/docs/qapi-code-gen.txt @@ -117,10 +117,13 @@ Example: ==== Expression documentation ==== -Each expression that isn't an include directive must be preceded by a +Each expression that isn't an include directive may be preceded by a documentation block. Such blocks are called expression documentation blocks. +When documentation is required (see pragma 'doc-required'), expression +documentation blocks are mandatory. + The documentation block consists of a first line naming the expression, an optional overview, a description of each argument (for commands and events) or member (for structs, unions and alternates), @@ -204,17 +207,17 @@ once. It is permissible for the schema to contain additional types not used by any commands or events in the Client JSON Protocol, for the side effect of generated C code used internally. -There are seven top-level expressions recognized by the parser: -'include', 'command', 'struct', 'enum', 'union', 'alternate', and -'event'. There are several groups of types: simple types (a number of -built-in types, such as 'int' and 'str'; as well as enumerations), -complex types (structs and two flavors of unions), and alternate types -(a choice between other types). The 'command' and 'event' expressions -can refer to existing types by name, or list an anonymous type as a -dictionary. Listing a type name inside an array refers to a -single-dimension array of that type; multi-dimension arrays are not -directly supported (although an array of a complex struct that -contains an array member is possible). +There are eight top-level expressions recognized by the parser: +'include', 'pragma', 'command', 'struct', 'enum', 'union', +'alternate', and 'event'. There are several groups of types: simple +types (a number of built-in types, such as 'int' and 'str'; as well as +enumerations), complex types (structs and two flavors of unions), and +alternate types (a choice between other types). The 'command' and +'event' expressions can refer to existing types by name, or list an +anonymous type as a dictionary. Listing a type name inside an array +refers to a single-dimension array of that type; multi-dimension +arrays are not directly supported (although an array of a complex +struct that contains an array member is possible). All names must begin with a letter, and contain only ASCII letters, digits, hyphen, and underscore. There are two exceptions: enum values @@ -282,7 +285,7 @@ The following types are predefined, and map to C as follows: QType QType JSON string matching enum QType values -=== Includes === +=== Include directives === Usage: { 'include': STRING } @@ -302,6 +305,20 @@ an outer file. The parser may be made stricter in the future to prevent incomplete include files. +=== Pragma directives === + +Usage: { 'pragma': DICT } + +The pragma directive lets you control optional generator behavior. +The dictionary's entries are pragma names and values. + +Pragma's scope is currently the complete schema. Setting the same +pragma to different values in parts of the schema doesn't work. + +Pragma 'doc-required' takes a boolean value. If true, documentation +is required. Default is false. + + === Struct types === Usage: { 'struct': STRING, 'data': DICT, '*base': STRUCT-NAME } |