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    Length: 3409 (0xd51)
    Types: TextFile
    Names: »systems.h«

└─⟦a05ed705a⟧ Bits:30007078 DKUUG GNU 2/12/89
    └─⟦847972ed9⟧ »./gdbm0.9.tar.Z« 
        └─⟦e41d67701⟧ 
            └─⟦this⟧ »gdbm/systems.h« 

TextFile

/* systems.h - Most of the system dependant code and defines are here. */

/*  GNU DBM  - DataBase Manager (database subroutines) by Philip A. Nelson
    Copyright (C) 1989  Free Software Foundation, Inc.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    You may contact the author by:
       e-mail:  phil@wwu.edu
      us-mail:  Philip A. Nelson
                Computer Science Department
                Western Washington University
                Bellingham, WA 98226
        phone:  (206) 676-3035
       
*************************************************************************/


/*         System V changes and defines.          */
/**************************************************/

#ifdef SYSV

/* File seeking needs L_SET defined .*/
#include <unistd.h>
#define L_SET SEEK_SET

/* Some files need fcntl.h for locking. */
#include <fcntl.h>
#define UNLOCK_FILE \
	{					\
	  struct flock flock;			\
	  flock.l_type = F_UNLCK;		\
	  flock.l_whence = 0;			\
	  flock.l_start = flock.l_len = 0L;	\
	  fcntl (dbf->desc, F_SETLK, &flock);	\
	}
#define READLOCK_FILE \
	{					\
	  struct flock flock;			\
	  flock.l_type = F_RDLCK;		\
	  flock.l_whence = 0;			\
	  flock.l_start = flock.l_len = 0L;	\
	  lock_val = fcntl (dbf->desc, F_SETLK, &flock);	\
	}
#define WRITELOCK_FILE \
	{					\
	  struct flock flock;			\
	  flock.l_type = F_WRLCK;		\
	  flock.l_whence = 0;			\
	  flock.l_start = flock.l_len = 0L;	\
	  lock_val = fcntl (dbf->desc, F_SETLK, &flock);	\
	}

/* Send bcmp to the right place. */
#include <memory.h>
#define bcmp(d1, d2, n)	memcmp(d1, d2, n)
#define bcopy(d1, d2, n) memcpy(d2, d1, n)

/* Sys V does not have fsync. */
#define fsync(f) sync(); sync()

/* Stat does not have a st_blksize field. */
#define STATBLKSIZE 512

/* Does not have rename(). */
#define NEED_RENAME
#endif

/*      End of System V changes and defines.      */
/**************************************************/



/* Alloca is builtin in gcc.  Use the builtin alloca if compiled with gcc. */
#ifdef __GNUC__
#define alloca __builtin_alloca
#else
extern char *alloca();
#endif

/* Malloc definition. */
extern char *malloc();


/* The BSD defines are the default defines.  If something is not
   defined above in the above conditional code, it will be set
   in the following code to the BSD code.  */

/* Default block size.  Some systems do not have blocksize in their
   stat record. This code uses the BSD blocksize from stat. */

#ifndef STATBLKSIZE
#define STATBLKSIZE file_stat.st_blksize
#endif


/* Locking is done differently on different systems.  Here is the BSD
   locking routines.  */

#ifndef UNLOCK_FILE
#define UNLOCK_FILE flock (dbf->desc, LOCK_UN)
#define READLOCK_FILE lock_val = flock (dbf->desc, LOCK_SH + LOCK_NB)
#define WRITELOCK_FILE lock_val = flock (dbf->desc, LOCK_EX + LOCK_NB)
#endif