diff --git a/contrib/list_example.c b/contrib/list_example.c new file mode 100644 index 000000000..0f62b864b --- /dev/null +++ b/contrib/list_example.c @@ -0,0 +1,74 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Copyright (C) 2021 by Andreas Fritiofson */ + +/* + * Simple example of using a circular doubly linked list through list.h + * + * gcc -I ../src/ list_example.c -o list_example + */ + +#include +#include +#include +#include + +static LIST_HEAD(threads); + +struct thread { + int id; + uint64_t tcb_address; + struct list_head lh; +}; + +void insert(struct thread *t) +{ + list_add_tail(&t->lh, &threads); +} + +void remove(struct thread *t) +{ + list_del(&t->lh); +} + +struct thread *lookup_id(int id) +{ + struct thread *t; + list_for_each_entry(t, &threads, lh) { + if (t->id == id) + return t; + } + return NULL; +} + +struct thread *lookup_tcb(uint64_t addr) +{ + struct thread *t; + list_for_each_entry(t, &threads, lh) { + if (t->tcb_address == addr) + return t; + } + return NULL; +} + +int main(void) +{ + struct thread t1 = { .id = 1, .tcb_address = 111111111 }; + struct thread t2 = { .id = 2, .tcb_address = 222222222 }; + struct thread t3 = { .id = 3, .tcb_address = 333333333 }; + + insert(&t1); + insert(&t2); + assert(lookup_id(1) == &t1); + assert(lookup_tcb(111111111) == &t1); + assert(lookup_id(2) == &t2); + assert(lookup_id(42) == NULL); + remove(&t1); + assert(lookup_id(1) == NULL); + insert(&t3); + remove(&t2); + assert(lookup_id(3) == &t3); + assert(lookup_tcb(333333333) == &t3); + assert(lookup_id(2) == NULL); + remove(&t3); + assert(list_empty(&threads)); +}