lib/libc/stdlib/ql.h

   1 /******************************************************************************
   2  *
   3  * Copyright (C) 2002 Jason Evans <jasone@FreeBSD.org>.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice(s), this list of conditions and the following disclaimer
  11  *    unmodified other than the allowable addition of one or more
  12  *    copyright notices.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice(s), this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
  19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  25  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  26  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
  27  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  28  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  ******************************************************************************/
  31
  32 #ifndef QL_H_
  33 #define QL_H_
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 /*
  39  * List definitions.
  40  */
  41 #define ql_head(a_type)                                                 \
  42 struct {                                                                \
  43         a_type *qlh_first;                                              \
  44 }
  45
  46 #define ql_head_initializer(a_head) {NULL}
  47
  48 #define ql_elm(a_type)  qr(a_type)
  49
  50 /* List functions. */
  51 #define ql_new(a_head) do {                                             \
  52         (a_head)->qlh_first = NULL;                                     \
  53 } while (0)
  54
  55 #define ql_elm_new(a_elm, a_field) qr_new((a_elm), a_field)
  56
  57 #define ql_first(a_head) ((a_head)->qlh_first)
  58
  59 #define ql_last(a_head, a_field)                                        \
  60         ((ql_first(a_head) != NULL)                                     \
  61             ? qr_prev(ql_first(a_head), a_field) : NULL)
  62
  63 #define ql_next(a_head, a_elm, a_field)                                 \
  64         ((ql_last(a_head, a_field) != (a_elm))                          \
  65             ? qr_next((a_elm), a_field) : NULL)
  66
  67 #define ql_prev(a_head, a_elm, a_field)                                 \
  68         ((ql_first(a_head) != (a_elm)) ? qr_prev((a_elm), a_field)      \
  69                                        : NULL)
  70
  71 #define ql_before_insert(a_head, a_qlelm, a_elm, a_field) do {          \
  72         qr_before_insert((a_qlelm), (a_elm), a_field);                  \
  73         if (ql_first(a_head) == (a_qlelm)) {                            \
  74                 ql_first(a_head) = (a_elm);                             \
  75         }                                                               \
  76 } while (0)
  77
  78 #define ql_after_insert(a_qlelm, a_elm, a_field)                        \
  79         qr_after_insert((a_qlelm), (a_elm), a_field)
  80
  81 #define ql_head_insert(a_head, a_elm, a_field) do {                     \
  82         if (ql_first(a_head) != NULL) {                                 \
  83                 qr_before_insert(ql_first(a_head), (a_elm), a_field);   \
  84         }                                                               \
  85         ql_first(a_head) = (a_elm);                                     \
  86 } while (0)
  87
  88 #define ql_tail_insert(a_head, a_elm, a_field) do {                     \
  89         if (ql_first(a_head) != NULL) {                                 \
  90                 qr_before_insert(ql_first(a_head), (a_elm), a_field);   \
  91         }                                                               \
  92         ql_first(a_head) = qr_next((a_elm), a_field);                   \
  93 } while (0)
  94
  95 #define ql_remove(a_head, a_elm, a_field) do {                          \
  96         if (ql_first(a_head) == (a_elm)) {                              \
  97                 ql_first(a_head) = qr_next(ql_first(a_head), a_field);  \
  98         }                                                               \
  99         if (ql_first(a_head) != (a_elm)) {                              \
 100                 qr_remove((a_elm), a_field);                            \
 101         } else {                                                        \
 102                 ql_first(a_head) = NULL;                                \
 103         }                                                               \
 104 } while (0)
 105
 106 #define ql_head_remove(a_head, a_type, a_field) do {                    \
 107         a_type *t = ql_first(a_head);                                   \
 108         ql_remove((a_head), t, a_field);                                \
 109 } while (0)
 110
 111 #define ql_tail_remove(a_head, a_type, a_field) do {                    \
 112         a_type *t = ql_last(a_head, a_field);                           \
 113         ql_remove((a_head), t, a_field);                                \
 114 } while (0)
 115
 116 #define ql_foreach(a_var, a_head, a_field)                              \
 117         qr_foreach((a_var), ql_first(a_head), a_field)
 118
 119 #define ql_reverse_foreach(a_var, a_head, a_field)                      \
 120         qr_reverse_foreach((a_var), ql_first(a_head), a_field)
 121
 122 #endif /* QL_H_ */