ltt/branches/poly/doc/developer/hook_prio.txt

   1 Linux Trace Toolkit
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   3 Mathieu Desnoyers 18-05-2004
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   6 Seeing that a very precise hook call ordering is needed when processing events
   7 (especially the order for calling state update hooks and event delivery hooks),
   8 this document defines a new type and interface that permits to merge all kind of
   9 hooks, eventually sorted by the priority associated to them.
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  11 - Type LttvHooks with priorities
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  13 This is a modification to the actual LttvHooks that associates a priority with
  14 each hook. The container for this type would be a garray, just like hook.c, but
  15 hooks would be added at the right position in the list, by priority. Hooks in a
  16 hook list are ordered by priority : from highest priority (0) to
  17 lowest (99). The default priority is 50 (defined as LTTV_PRIO_DEFAULT).
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  19 A new lttv_hooks_call_merge that will get the hooks from two hook lists in the
  20 right order will deal with the multiple lists priority problem.
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