include/grub/list.h

   1 /* list.h - header for grub list */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2009  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifndef GRUB_LIST_HEADER
  21 #define GRUB_LIST_HEADER 1
  22
  23 #include <grub/symbol.h>
  24 #include <grub/err.h>
  25 #include <grub/compiler.h>
  26
  27 struct grub_list
  28 {
  29   struct grub_list *next;
  30   struct grub_list **prev;
  31 };
  32 typedef struct grub_list *grub_list_t;
  33
  34 void EXPORT_FUNC(grub_list_push) (grub_list_t *head, grub_list_t item);
  35 void EXPORT_FUNC(grub_list_remove) (grub_list_t item);
  36
  37 #define FOR_LIST_ELEMENTS(var, list) for ((var) = (list); (var); (var) = (var)->next)
  38 #define FOR_LIST_ELEMENTS_SAFE(var, nxt, list) for ((var) = (list), (nxt) = ((var) ? (var)->next : 0); (var); (var) = (nxt), ((nxt) = (var) ? (var)->next : 0))
  39
  40 static inline void *
  41 grub_bad_type_cast_real (int line, const char *file)
  42      ATTRIBUTE_ERROR ("bad type cast between incompatible grub types");
  43
  44 static inline void *
  45 grub_bad_type_cast_real (int line, const char *file)
  46 {
  47   grub_fatal ("error:%s:%u: bad type cast between incompatible grub types",
  48               file, line);
  49 }
  50
  51 #define grub_bad_type_cast() grub_bad_type_cast_real(__LINE__, GRUB_FILE)
  52
  53 #define GRUB_FIELD_MATCH(ptr, type, field) \
  54   ((char *) &(ptr)->field == (char *) &((type) (ptr))->field)
  55
  56 #define GRUB_AS_LIST(ptr) \
  57   (GRUB_FIELD_MATCH (ptr, grub_list_t, next) && GRUB_FIELD_MATCH (ptr, grub_list_t, prev) ? \
  58    (grub_list_t) ptr : (grub_list_t) grub_bad_type_cast ())
  59
  60 #define GRUB_AS_LIST_P(pptr) \
  61   (GRUB_FIELD_MATCH (*pptr, grub_list_t, next) && GRUB_FIELD_MATCH (*pptr, grub_list_t, prev) ? \
  62    (grub_list_t *) (void *) pptr : (grub_list_t *) grub_bad_type_cast ())
  63
  64 struct grub_named_list
  65 {
  66   struct grub_named_list *next;
  67   struct grub_named_list **prev;
  68   char *name;
  69 };
  70 typedef struct grub_named_list *grub_named_list_t;
  71
  72 void * EXPORT_FUNC(grub_named_list_find) (grub_named_list_t head,
  73                                           const char *name);
  74
  75 #define GRUB_AS_NAMED_LIST(ptr) \
  76   ((GRUB_FIELD_MATCH (ptr, grub_named_list_t, next) \
  77     && GRUB_FIELD_MATCH (ptr, grub_named_list_t, prev)  \
  78     && GRUB_FIELD_MATCH (ptr, grub_named_list_t, name))? \
  79    (grub_named_list_t) ptr : (grub_named_list_t) grub_bad_type_cast ())
  80
  81 #define GRUB_AS_NAMED_LIST_P(pptr) \
  82   ((GRUB_FIELD_MATCH (*pptr, grub_named_list_t, next) \
  83     && GRUB_FIELD_MATCH (*pptr, grub_named_list_t, prev)   \
  84     && GRUB_FIELD_MATCH (*pptr, grub_named_list_t, name))? \
  85    (grub_named_list_t *) (void *) pptr : (grub_named_list_t *) grub_bad_type_cast ())
  86
  87 #endif /* ! GRUB_LIST_HEADER */