Stream object

A CTF stream.

Stream objects are used in the streams property of the metadata object.

Properties

Property	Type	Description	Required?	Default value
packet-context-type	Type object or string (alias name)	Type of packet context (must be a [[structure type object	Structure type object]])	Required
event-header-type	Type object or string (alias name)	Type of event header (must be a [[structure type object	Structure type object]])	Optional
event-context-type	Type object or string (alias name)	Type of stream event context (must be a [[structure type object	Structure type object]])	Optional
events	Associative array of event names (string) to [[event objects	Event object]]	Stream events	Required
[[$include	Including external YAML files]]	String or array of strings	Include base properties from external YAML file(s)	Optional

All the properties which have a default value can also be set to null to force this default value. This is especially useful when including external YAML files.

Each field of the packet context structure type (packet-context-type property) corresponds to one parameter of the generated packet opening function (prefixed with spc_), except for the following special fields, which are automatically written if present:

• timestamp_begin and timestamp_end (unsigned integer type objects, with a clock value property mapping): resp. open and close timestamps
• packet_size (unsigned integer type object, mandatory): packet size
• content_size (unsigned integer type object, mandatory): content size
• events_discarded (unsigned integer type object): number of discarded events so far

The timestamp_end field must exist if the timestamp_begin field exists, and vice versa.

Each field of the event header structure type (event-header-type property) corresponds to one parameter of the generated tracing function (prefixed with eh_) (for a given event), except for the following special fields, which are automatically written if present:

• id (unsigned integer type object): event ID
• timestamp (unsigned integer type object, with a clock value property mapping): event timestamp

The id field must exist if there's more than one defined event in the stream.

Each field of the stream event context structure type (event-context-type property) corresponds to one parameter of the generated tracing function (prefixed with seh_) (for a given event).

Each field name of the packet-context-type, event-header-type, and event-context-type properties must be a valid C identifier.

The events property must contain at least one entry.

Example

packet-context-type:
  class: struct
  fields:
    timestamp_begin: clock-int
    timestamp_end: clock-int
    packet_size: uint32
    content_size: uint32
    events_discarded: uint16
    my_custom_field: int12
event-header-type:
  class: struct
  fields:
    id: uint16
    timestamp: clock-int
event-context-type:
  class: struct
  fields:
    obj_id: uint8
events:
  msg_in:
    payload-type: msg-type