release/src/router/hotplug2/childlist.c

   1 /*****************************************************************************\
   2 *  _  _       _          _              ___                                   *
   3 * | || | ___ | |_  _ __ | | _  _  __ _ |_  )                                  *
   4 * | __ |/ _ \|  _|| '_ \| || || |/ _` | / /                                   *
   5 * |_||_|\___/ \__|| .__/|_| \_,_|\__, |/___|                                  *
   6 *                 |_|            |___/                                        *
   7 \*****************************************************************************/
   8
   9 #include <stdio.h>
  10 #include <unistd.h>
  11 #include <stdlib.h>
  12 #include <sys/wait.h>
  13 #include <sys/types.h>
  14
  15 #include "mem_utils.h"
  16 #include "hotplug2.h"
  17 #include "childlist.h"
  18
  19  struct hotplug2_child_t *add_child(struct hotplug2_child_t *child, pid_t pid, event_seqnum_t seqnum) {
  20         void *tmp;
  21
  22         if (child == NULL) {
  23                 child = xmalloc(sizeof(struct hotplug2_child_t));
  24                 tmp = NULL;
  25         } else {
  26                 for (; child->next; child = child->next);
  27
  28                 child->next = xmalloc(sizeof(struct hotplug2_child_t));
  29                 tmp = child;
  30                 child = child->next;
  31         }
  32
  33         child->seqnum = seqnum;
  34         child->pid = pid;
  35         child->prev = tmp;
  36         child->next = NULL;
  37
  38         return child;
  39 }
  40
  41 struct hotplug2_child_t *remove_child_by_pid(struct hotplug2_child_t *child, pid_t pid, event_seqnum_t *largest_seqnum, int *child_c) {
  42         struct hotplug2_child_t *tmp_child;
  43
  44         if (child == NULL) {
  45                 ERROR("remove_child_by_pid", "Invalid child list passed (NULL).");
  46                 return NULL;
  47         }
  48
  49         tmp_child = child;
  50
  51         for (; child->prev && child->pid != pid; child = child->prev);
  52
  53         if (child->pid != pid) {
  54                 return tmp_child;
  55         }
  56
  57         if (child->prev != NULL)
  58                 ((struct hotplug2_child_t *)(child->prev))->next = child->next;
  59
  60         if (child->next != NULL)
  61                 ((struct hotplug2_child_t *)(child->next))->prev = child->prev;
  62
  63         if (largest_seqnum != NULL)
  64                 if (child->seqnum > *largest_seqnum)
  65                         *largest_seqnum = child->seqnum;
  66
  67         if (child_c != NULL)
  68                 *child_c -= 1;
  69
  70         if (child == tmp_child) {
  71                 if (child->next != NULL)
  72                         tmp_child = child->next;
  73                 else if (child->prev != NULL)
  74                         tmp_child = child->prev;
  75                 else
  76                         tmp_child = NULL;
  77         }
  78
  79         /* We always want the rightmost */
  80         if (tmp_child != NULL)
  81                 for (; tmp_child->next; tmp_child = tmp_child->next);
  82
  83         free(child);
  84         return tmp_child;
  85 }
  86