upipe/upipe_helper_flow_format.h header reference

Upipe helper functions for flow format More

• upipe/ubase.h
• upipe/ubuf.h
• upipe/upipe.h
• upipe/urequest.h
• upipe/uref_dump.h

• typedef int (*upipe_helper_flow_format_check)(struct upipe *, struct uref *)
• typedef int (*upipe_helper_flow_format_register)(struct upipe *, struct urequest *)

• UPIPE_HELPER_FLOW_FORMAT

Upipe helper functions for flow format

This macro is declared in upipe/upipe_helper_flow_format.h source file, line 98.

This macro declares four functions dealing with the flow format used on the output of a pipe.

You must add one member to your private upipe structure, for instance:

You must also declare UPIPE_HELPER_UPIPE prior to using this macro, and provide two functions which will be called 1/ when the flow format is provided, 2/ and 3/ when a request needs to be registered/unregistered.

Supposing the name of your structure is upipe_foo, it declares:

• void upipe_foo_init_flow_format(struct upipe *upipe)

  Typically called in your upipe_foo_alloc() function.

• int upipe_foo_provide_flow_format(struct upipe *upipe, va_list args)

  Internal function called when the request is answered.

• int upipe_foo_require_flow_format(struct upipe *upipe,
struct uref *flow_format)

  Initializes and registers the request to get a flow format. The base flow format belongs to the callee and will be eventually freed.

• void upipe_foo_clean_flow_format(struct upipe *upipe)

  Typically called from your upipe_foo_free() function.

Parameter list:

• STRUCTURE: name of your private upipe structure
• REQUEST: name of the struct urequest field of your private upipe structure
• CHECK: function called after a uref manager has been received
• REGISTER: function called to register a request
• UNREGISTER: function called to unregister a request

This macro is declared in upipe/upipe_helper_flow_format.h source file, line 31.

This typedef is declared in upipe/upipe_helper_flow_format.h source file, line 48.

This typedef defines a function that will be called after a flow_format has been received. The second argument is the amended flow format (belongs to the callee).

This typedef is declared in upipe/upipe_helper_flow_format.h source file, line 53.

This typedef defines a function that will be called to register or unregister a request.