1 /* 2 * wpa_supplicant/hostapd - State machine definitions 3 * Copyright (c) 2002-2005, Jouni Malinen <j (at) w1.fi> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Alternatively, this software may be distributed under the terms of BSD 10 * license. 11 * 12 * See README and COPYING for more details. 13 * 14 * This file includes a set of pre-processor macros that can be used to 15 * implement a state machine. In addition to including this header file, each 16 * file implementing a state machine must define STATE_MACHINE_DATA to be the 17 * data structure including state variables (enum machine_state, 18 * Boolean changed), and STATE_MACHINE_DEBUG_PREFIX to be a string that is used 19 * as a prefix for all debug messages. If SM_ENTRY_MA macro is used to define 20 * a group of state machines with shared data structure, STATE_MACHINE_ADDR 21 * needs to be defined to point to the MAC address used in debug output. 22 * SM_ENTRY_M macro can be used to define similar group of state machines 23 * without this additional debug info. 24 */ 25 26 #ifndef STATE_MACHINE_H 27 #define STATE_MACHINE_H 28 29 /** 30 * SM_STATE - Declaration of a state machine function 31 * @machine: State machine name 32 * @state: State machine state 33 * 34 * This macro is used to declare a state machine function. It is used in place 35 * of a C function definition to declare functions to be run when the state is 36 * entered by calling SM_ENTER or SM_ENTER_GLOBAL. 37 */ 38 #define SM_STATE(machine, state) \ 39 static void sm_ ## machine ## _ ## state ## _Enter(STATE_MACHINE_DATA *sm, \ 40 int global) 41 42 /** 43 * SM_ENTRY - State machine function entry point 44 * @machine: State machine name 45 * @state: State machine state 46 * 47 * This macro is used inside each state machine function declared with 48 * SM_STATE. SM_ENTRY should be in the beginning of the function body, but 49 * after declaration of possible local variables. This macro prints debug 50 * information about state transition and update the state machine state. 51 */ 52 #define SM_ENTRY(machine, state) \ 53 if (!global || sm->machine ## _state != machine ## _ ## state) { \ 54 sm->changed = TRUE; \ 55 wpa_printf(MSG_DEBUG, STATE_MACHINE_DEBUG_PREFIX ": " #machine \ 56 " entering state " #state); \ 57 } \ 58 sm->machine ## _state = machine ## _ ## state; 59 60 /** 61 * SM_ENTRY_M - State machine function entry point for state machine group 62 * @machine: State machine name 63 * @_state: State machine state 64 * @data: State variable prefix (full variable: prefix_state) 65 * 66 * This macro is like SM_ENTRY, but for state machine groups that use a shared 67 * data structure for more than one state machine. Both machine and prefix 68 * parameters are set to "sub-state machine" name. prefix is used to allow more 69 * than one state variable to be stored in the same data structure. 70 */ 71 #define SM_ENTRY_M(machine, _state, data) \ 72 if (!global || sm->data ## _ ## state != machine ## _ ## _state) { \ 73 sm->changed = TRUE; \ 74 wpa_printf(MSG_DEBUG, STATE_MACHINE_DEBUG_PREFIX ": " \ 75 #machine " entering state " #_state); \ 76 } \ 77 sm->data ## _ ## state = machine ## _ ## _state; 78 79 /** 80 * SM_ENTRY_MA - State machine function entry point for state machine group 81 * @machine: State machine name 82 * @_state: State machine state 83 * @data: State variable prefix (full variable: prefix_state) 84 * 85 * This macro is like SM_ENTRY_M, but a MAC address is included in debug 86 * output. STATE_MACHINE_ADDR has to be defined to point to the MAC address to 87 * be included in debug. 88 */ 89 #define SM_ENTRY_MA(machine, _state, data) \ 90 if (!global || sm->data ## _ ## state != machine ## _ ## _state) { \ 91 sm->changed = TRUE; \ 92 wpa_printf(MSG_DEBUG, STATE_MACHINE_DEBUG_PREFIX ": " MACSTR " " \ 93 #machine " entering state " #_state, \ 94 MAC2STR(STATE_MACHINE_ADDR)); \ 95 } \ 96 sm->data ## _ ## state = machine ## _ ## _state; 97 98 /** 99 * SM_ENTER - Enter a new state machine state 100 * @machine: State machine name 101 * @state: State machine state 102 * 103 * This macro expands to a function call to a state machine function defined 104 * with SM_STATE macro. SM_ENTER is used in a state machine step function to 105 * move the state machine to a new state. 106 */ 107 #define SM_ENTER(machine, state) \ 108 sm_ ## machine ## _ ## state ## _Enter(sm, 0) 109 110 /** 111 * SM_ENTER_GLOBAL - Enter a new state machine state based on global rule 112 * @machine: State machine name 113 * @state: State machine state 114 * 115 * This macro is like SM_ENTER, but this is used when entering a new state 116 * based on a global (not specific to any particular state) rule. A separate 117 * macro is used to avoid unwanted debug message floods when the same global 118 * rule is forcing a state machine to remain in on state. 119 */ 120 #define SM_ENTER_GLOBAL(machine, state) \ 121 sm_ ## machine ## _ ## state ## _Enter(sm, 1) 122 123 /** 124 * SM_STEP - Declaration of a state machine step function 125 * @machine: State machine name 126 * 127 * This macro is used to declare a state machine step function. It is used in 128 * place of a C function definition to declare a function that is used to move 129 * state machine to a new state based on state variables. This function uses 130 * SM_ENTER and SM_ENTER_GLOBAL macros to enter new state. 131 */ 132 #define SM_STEP(machine) \ 133 static void sm_ ## machine ## _Step(STATE_MACHINE_DATA *sm) 134 135 /** 136 * SM_STEP_RUN - Call the state machine step function 137 * @machine: State machine name 138 * 139 * This macro expands to a function call to a state machine step function 140 * defined with SM_STEP macro. 141 */ 142 #define SM_STEP_RUN(machine) sm_ ## machine ## _Step(sm) 143 144 #endif /* STATE_MACHINE_H */ 145
