/*--- This software is copyrighted by the Regents of the University of California, and other parties. The following terms apply to all files associated with the software unless explicitly disclaimed in individual files. The authors hereby grant permission to use, copy, modify, distribute, and license this software and its documentation for any purpose, provided that existing copyright notices are retained in all copies and that this notice is included verbatim in any distributions. No written agreement, license, or royalty fee is required for any of the authorized uses. Modifications to this software may be copyrighted by their authors and need not follow the licensing terms described here, provided that the new terms are clearly indicated on the first page of each file where they apply. IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION, OR ANY DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. GOVERNMENT USE: If you are acquiring this software on behalf of the U.S. government, the Government shall have only "Restricted Rights" in the software and related documentation as defined in the Federal Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2). If you are acquiring the software on behalf of the Department of Defense, the software shall be classified as "Commercial Computer Software" and the Government shall have only "Restricted Rights" as defined in Clause 252.227-7013 (c) (1) of DFARs. Notwithstanding the foregoing, the authors grant the U.S. Government and others acting in its behalf permission to use and distribute the software in accordance with the terms specified in this license. ---*/ #ifndef _STATEMACHINE_H #define _STATEMACHINE_H #include #include #include #include "../lladd/src/lladd/page.h" #include #include #define MAX_STATE_NAME UCHAR_MAX-1 /* If a transition's post state is OVERRIDDEN_STATE, then the new state is read from the return value of the callback_fcn. If callback_fcn returns OVERRIDDEN_STATE, then no transition is performed. Otherwise, then callback_fcn returns a standard boolean value. (0-> no transition, !=0 -> take transition.) */ #define MAX_STATE_COUNT UCHAR_MAX+1 #define MAX_APP_STATE_SIZE (sizeof(int) * 32) #define NULL_MACHINE (ULONG_MAX-1) #define NULL_STATE MAX_STATE_NAME #define NULL_STATE_TOMBSTONE (MAX_STATE_NAME-1) #define OVERRIDDEN_STATE (MAX_STATE_NAME-2) #define START_STATE 0 typedef unsigned char dfa_bool; typedef unsigned char state_name; /** This struct contains all of the information associated with an instance of a state machine. When combined with a set of states and transitions, this provides enough information to actually execute a machine. The page record contains application specific state, which must be stored in transactional, or otherwise reliable storage. */ typedef struct stateMachine { /** The unique identifier of this state machine. */ state_machine_id machine_id; /** The wall-clock time of the last transition made by this machine. (Used to abort hung machines.)*/ time_t last_transition; /** A pointer to this state machine's page in memory. */ Page * page; /** The recordid of page (for recovery) */ recordid page_id; /** The current state of this machine, or NULL_STATE for machines that should be garbage collected. */ state_name current_state; pthread_t worker_thread; int pending; pthread_mutex_t * mutex; pthread_cond_t * sleepCond; Message message; char message_recipient[MAX_ADDRESS_LENGTH]; int app_state[MAX_APP_STATE_SIZE]; } StateMachine; typedef state_name(callback_fcn)(void * dfaSet, StateMachine * stateMachine, Message * m, char * from); /* All function pointers follow this prototype: TODO and may be null if no function needs to be executed. */ typedef struct state { /** The name of this state. Usually just the index of this state in the states array. */ state_name name; /** A function pointer that will be periodically executed when the machine is in this state. Most network transmits belong here, while 'guards' belong in fcn_ptr in the Transistion struct. */ callback_fcn* retry_fcn; /** NULL unless the machine can be aborted while in this state. If not-null, then it should point to a function that performs a No-op or does any house-keeping that should be performed before the machine gets nuked. Should normally be a callback_fcn, as defined in libdfa.h */ callback_fcn* abort_fcn; } State; typedef struct transition { /** A unique (per machine type) identifier for this transition. */ state_name remote_state; /** The start state for this transition */ state_name pre_state; /** The stop state. */ state_name post_state; /** Executed when the machine traverses this arc. Returns false if the arc should not be traversed. For sane semantics, exactly one transition from a given start state should return true given the same network message. */ callback_fcn * fcn_ptr; /** If true, this transitions causes a force to disk after fcn_ptr returns, but before the retry_fcn for the state is automatically executed the first time. */ dfa_bool force; } Transition; #endif