doc/examples/wfstack/cds_wfs_pop_all_blocking.c

   1 // SPDX-FileCopyrightText: 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   2 //
   3 // SPDX-License-Identifier: MIT
   4
   5 /*
   6  * This example shows how to pop all nodes from a wfstack.
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11
  12 #include <urcu/wfstack.h>       /* Wait-free stack */
  13 #include <urcu/compiler.h>      /* For CAA_ARRAY_SIZE */
  14
  15 /*
  16  * Nodes populated into the stack.
  17  */
  18 struct mynode {
  19         int value;                      /* Node content */
  20         struct cds_wfs_node node;       /* Chaining in stack */
  21 };
  22
  23 int main(void)
  24 {
  25         int values[] = { -5, 42, 36, 24, };
  26         struct cds_wfs_stack mystack;   /* Stack */
  27         unsigned int i;
  28         int ret = 0;
  29         struct cds_wfs_node *snode, *sn;
  30         struct cds_wfs_head *shead;
  31
  32         cds_wfs_init(&mystack);
  33
  34         /*
  35          * Push nodes.
  36          */
  37         for (i = 0; i < CAA_ARRAY_SIZE(values); i++) {
  38                 struct mynode *node;
  39
  40                 node = malloc(sizeof(*node));
  41                 if (!node) {
  42                         ret = -1;
  43                         goto end;
  44                 }
  45
  46                 cds_wfs_node_init(&node->node);
  47                 node->value = values[i];
  48                 cds_wfs_push(&mystack, &node->node);
  49         }
  50
  51         /*
  52          * Pop all nodes from mystack into shead. The head can the be
  53          * used for iteration.
  54          */
  55         shead = cds_wfs_pop_all_blocking(&mystack);
  56
  57         /*
  58          * Show the stack content, iterate in reverse order of push,
  59          * from newest to oldest. Use cds_wfs_for_each_blocking_safe()
  60          * so we can free the nodes as we iterate.
  61          */
  62         printf("mystack content:");
  63         cds_wfs_for_each_blocking_safe(shead, snode, sn) {
  64                 struct mynode *node =
  65                         caa_container_of(snode, struct mynode, node);
  66                 printf(" %d", node->value);
  67                 free(node);
  68         }
  69         printf("\n");
  70 end:
  71         cds_wfs_destroy(&mystack);
  72         return ret;
  73 }