LXR linux-old/include/asm-s390/queue.h

   1/*
   2 *  include/asm-s390/queue.h
   3 *
   4 *  S390 version
   5 *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6 *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
   7 *
   8 *  A little set of queue utilies.
   9 */
  10#ifndef __ASM_QUEUE_H
  11#define __ASM_QUEUE_H
  12#include <linux/stddef.h>
  13
  14typedef struct queue
  15{
  16        struct queue *next;     
  17} queue;
  18
  19typedef queue list;
  20
  21typedef struct
  22{
  23        queue *head;
  24        queue *tail;
  25} qheader;
  26
  27static __inline__ void init_queue(qheader *qhead)
  28{
  29        memset(qhead,0,sizeof(*qhead));
  30}
  31
  32static __inline__ void enqueue_tail(qheader *qhead,queue *member)
  33{       
  34        if(member)
  35        {
  36                queue *tail=qhead->tail;
  37
  38                if(tail)
  39                        tail->next=member;
  40                else
  41                        
  42                        qhead->head=member;
  43                qhead->tail=member;
  44                member->next=NULL;
  45        }
  46} 
  47
  48static __inline__ queue *dequeue_head(qheader *qhead)
  49{
  50        queue *head=qhead->head,*next_head;
  51
  52        if(head)
  53        {
  54                next_head=head->next;
  55                qhead->head=next_head;
  56                if(!next_head)
  57                        qhead->tail=NULL;
  58        }
  59        return(head);
  60}
  61
  62static __inline__ void init_list(list **lhead)
  63{
  64        *lhead=NULL;
  65}
  66
  67static __inline__ void add_to_list(list **lhead,list *member)
  68{
  69        member->next=*lhead;
  70        *lhead=member;
  71}
  72
  73static __inline__ list *remove_listhead(list **lhead)
  74{
  75        list *oldhead=*lhead;
  76
  77        if(oldhead)
  78                *lhead=(*lhead)->next;
  79        return(oldhead);
  80}
  81
  82static __inline__ void add_to_list_tail(list **lhead,list *member)
  83{
  84        list *curr,*prev;
  85        if(*lhead==NULL)
  86                *lhead=member;
  87        else
  88        {
  89                prev=*lhead;
  90                for(curr=(*lhead)->next;curr!=NULL;curr=curr->next)
  91                        prev=curr;
  92                prev->next=member;
  93        }
  94}
  95static __inline__ void add_to_list_tail_null(list **lhead,list *member)
  96{
  97        member->next=NULL;
  98        add_to_list_tail_null(lhead,member);
  99}
 100
 101
 102static __inline__ int is_in_list(list *lhead,list *member)
 103{
 104        list *curr;
 105
 106        for(curr=lhead;curr!=NULL;curr=curr->next)
 107                if(curr==member)
 108                        return(1);
 109        return(0);
 110}
 111
 112static __inline__ int get_prev(list *lhead,list *member,list **prev)
 113{
 114        list *curr;
 115
 116        *prev=NULL;
 117        for(curr=lhead;curr!=NULL;curr=curr->next)
 118        {
 119                if(curr==member)
 120                        return(1);
 121                *prev=curr;
 122        }
 123        *prev=NULL;
 124        return(0);
 125}
 126
 127
 128
 129static __inline__ int remove_from_list(list **lhead,list *member)
 130{
 131        list *prev;
 132
 133        if(get_prev(*lhead,member,&prev))
 134        {
 135
 136                if(prev)
 137                        prev->next=member->next;
 138                else
 139                        *lhead=member->next;
 140                return(1);
 141        }
 142        return(0);
 143}
 144
 145static __inline__ int remove_from_queue(qheader *qhead,queue *member)
 146{
 147        queue *prev;
 148
 149        if(get_prev(qhead->head,(list *)member,(list **)&prev))
 150        {
 151
 152                if(prev)
 153                {
 154                        prev->next=member->next;
 155                        if(prev->next==NULL)
 156                                qhead->tail=prev;
 157                }
 158                else
 159                {
 160                        if(qhead->head==qhead->tail)
 161                                qhead->tail=NULL;
 162                        qhead->head=member->next;
 163                }
 164                return(1);
 165        }
 166        return(0);
 167}
 168
 169#endif /* __ASM_QUEUE_H */
 170
 171