/* * BIRD Library -- Locking * * (c) 2020--2021 Maria Matejka <mq@jmq.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_LOCKING_H_ #define _BIRD_LOCKING_H_ struct domain_generic; /* Here define the global lock order; first to last. */ struct lock_order { struct domain_generic *the_bird; struct domain_generic *control; struct domain_generic *proto; struct domain_generic *service; struct domain_generic *rtable; struct domain_generic *attrs; struct domain_generic *resource; }; extern _Thread_local struct lock_order locking_stack; extern _Thread_local struct domain_generic **last_locked; #define DOMAIN(type) struct domain__##type #define DEFINE_DOMAIN(type) DOMAIN(type) { struct domain_generic *type; } #define DOMAIN_ORDER(type) OFFSETOF(struct lock_order, type) #define DOMAIN_NEW(type, name) (DOMAIN(type)) { .type = domain_new(name, DOMAIN_ORDER(type)) } struct domain_generic *domain_new(const char *name, uint order); #define DOMAIN_FREE(type, d) domain_free((d).type) void domain_free(struct domain_generic *); #define DOMAIN_NAME(type, d) domain_name((d).type) const char *domain_name(struct domain_generic *); #define DOMAIN_NULL(type) (DOMAIN(type)) {} #define LOCK_DOMAIN(type, d) do_lock(((d).type), &(locking_stack.type)) #define UNLOCK_DOMAIN(type, d) do_unlock(((d).type), &(locking_stack.type)) #define DOMAIN_IS_LOCKED(type, d) (((d).type) == (locking_stack.type)) #define DG_IS_LOCKED(d) ((d) == *(DG_LSP(d))) /* Internal for locking */ void do_lock(struct domain_generic *dg, struct domain_generic **lsp); void do_unlock(struct domain_generic *dg, struct domain_generic **lsp); uint dg_order(struct domain_generic *dg); #define DG_LSP(d) ((struct domain_generic **) (((void *) &locking_stack) + dg_order(d))) #define DG_LOCK(d) do_lock(d, DG_LSP(d)) #define DG_UNLOCK(d) do_unlock(d, DG_LSP(d)) /* Use with care. To be removed in near future. */ DEFINE_DOMAIN(the_bird); extern DOMAIN(the_bird) the_bird_domain; #define the_bird_lock() LOCK_DOMAIN(the_bird, the_bird_domain) #define the_bird_unlock() UNLOCK_DOMAIN(the_bird, the_bird_domain) #define the_bird_locked() DOMAIN_IS_LOCKED(the_bird, the_bird_domain) #define ASSERT_THE_BIRD_LOCKED ({ if (!the_bird_locked()) bug("The BIRD lock must be locked here: %s:%d", __FILE__, __LINE__); }) #endif