Subversion Repositories HelenOS

Rev

Rev 1963 | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1. /*
  2.  * Copyright (C) 2001-2004 Jakub Jermar
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. #ifndef __CONTEXT_H__
  30. #define __CONTEXT_H__
  31.  
  32. #include <arch/types.h>
  33. #include <typedefs.h>
  34. #include <arch/context.h>
  35.  
  36.  
  37. #ifndef context_set
  38. #define context_set(c, _pc, stack, size)    \
  39.     (c)->pc = (__address) (_pc);        \
  40.     (c)->sp = ((__address) (stack)) + (size) - SP_DELTA;
  41. #endif /* context_set */
  42.  
  43. extern int context_save_arch(context_t *c);
  44. extern void context_restore_arch(context_t *c) __attribute__ ((noreturn));
  45.  
  46. /** Save register context.
  47.  *
  48.  * Save current register context (including stack pointers)
  49.  * to context structure.
  50.  *
  51.  * Note that call to context_restore() will return at the same
  52.  * address as the corresponding call to context_save().
  53.  *
  54.  * This MUST be a macro, gcc -O0 does not inline functions even
  55.  * if they are marked inline and context_save_arch must be called
  56.  * from level <= that when context_restore is called.
  57.  *
  58.  * @param c Context structure.
  59.  *
  60.  * @return context_save() returns 1, context_restore() returns 0.
  61.  */
  62. #define context_save(c)   context_save_arch(c)
  63.  
  64. /** Restore register context.
  65.  *
  66.  * Restore previously saved register context (including stack pointers)
  67.  * from context structure.
  68.  *
  69.  * Note that this function does not normally return.
  70.  * Instead, it returns at the same address as the
  71.  * corresponding call to context_save(), the only
  72.  * difference being return value.
  73.  *
  74.  * Note that content of any local variable defined by
  75.  * the caller of context_save() is undefined after
  76.  * context_restore().
  77.  *
  78.  * @param c Context structure.
  79.  */
  80. static inline void context_restore(context_t *c)
  81. {
  82.     context_restore_arch(c);
  83. }
  84.  
  85. #endif
  86.