elk/include/stkmem.h

93 lines
2.7 KiB
C

/* stkmem.h
*
* $Id$
*
* Copyright 1990, 1991, 1992, 1993, 1994, 1995, Oliver Laumann, Berlin
* Copyright 2002, 2003 Sam Hocevar <sam@zoy.org>, Paris
*
* This software was derived from Elk 1.2, which was Copyright 1987, 1988,
* 1989, Nixdorf Computer AG and TELES GmbH, Berlin (Elk 1.2 has been written
* by Oliver Laumann for TELES Telematic Services, Berlin, in a joint project
* between TELES and Nixdorf Microprocessor Engineering, Berlin).
*
* Oliver Laumann, TELES GmbH, Nixdorf Computer AG and Sam Hocevar, as co-
* owners or individual owners of copyright in this software, grant to any
* person or company a worldwide, royalty free, license to
*
* i) copy this software,
* ii) prepare derivative works based on this software,
* iii) distribute copies of this software or derivative works,
* iv) perform this software, or
* v) display this software,
*
* provided that this notice is not removed and that neither Oliver Laumann
* nor Teles nor Nixdorf are deemed to have made any representations as to
* the suitability of this software for any purpose nor are held responsible
* for any defects of this software.
*
* THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
*/
#ifdef USE_ALLOCA
#ifdef HAVE_ALLOCA_H
# include <alloca.h>
#endif
/* #pragma must be indented to prevent some C-compilers from complaining
* about "undefined control".
*/
#ifdef PRAGMA_ALLOCA
#pragma alloca
#endif
#if !defined(alloca) && !defined(__GNUC__)
C_LINKAGE_BEGIN
extern char *alloca P_((int));
C_LINKAGE_END
#endif
/* MIPS cc under Ultrix 4.2 requires argument to alloca() to be
* parenthesized if it's a compound expression.
*
* Declare variable in Alloca_Begin and reference it in Alloca to make
* sure users won't forget Alloca_Begin when using macros like
* Get_String_Stack().
*/
#define Alloca_Begin int _Check_Alloca_Begin
#define Alloca(ret,type,size) (_Check_Alloca_Begin = 0,\
(ret) = (type)alloca((size)))
#define Alloca_End
#else /* USE_ALLOCA */
extern MEM_NODE *Mem_List;
extern char *Mem_Alloc P_((unsigned));
#define Alloca_Begin MEM_NODE *_mem_first = 0
#define Alloca(ret,type,size) {\
register MEM_NODE *_p;\
_p = (MEM_NODE*)Mem_Alloc ((unsigned)(size) + sizeof(MEM_NODE));\
_p->next = Mem_List;\
_p->len = (size);\
_p->refcnt = 1;\
Mem_List = _p;\
if (_mem_first == 0) _mem_first = _p;\
(ret) = (type)(_p+1);\
}
#define Alloca_End {\
register MEM_NODE *_p, *_q;\
if (_mem_first != 0) {\
_p = Mem_List;\
do {\
_q = _p;\
_p = _p->next;\
if (--_q->refcnt == 0)\
free ((char *)_q);\
} while (_q != _mem_first);\
Mem_List = _p;\
}\
}
#endif