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author | rgrimes <rgrimes@FreeBSD.org> | 1993-06-12 14:58:17 +0000 |
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committer | rgrimes <rgrimes@FreeBSD.org> | 1993-06-12 14:58:17 +0000 |
commit | 25062ba061871945759b3baa833fe64969383e40 (patch) | |
tree | 2d1c31051ed0dbaad984013c9fe695b1a01e1c39 /sys/ddb/db_access.c | |
parent | f078b88a160c467761b3f3641f05dfd0aa3f7753 (diff) | |
download | FreeBSD-src-25062ba061871945759b3baa833fe64969383e40.zip FreeBSD-src-25062ba061871945759b3baa833fe64969383e40.tar.gz |
Initial import, 0.1 + pk 0.2.4-B1
Diffstat (limited to 'sys/ddb/db_access.c')
-rw-r--r-- | sys/ddb/db_access.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/sys/ddb/db_access.c b/sys/ddb/db_access.c new file mode 100644 index 0000000..63368c0 --- /dev/null +++ b/sys/ddb/db_access.c @@ -0,0 +1,116 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie the + * rights to redistribute these changes. + */ +/* + * HISTORY + * $Log: db_access.c,v $ + * Revision 1.1 1992/03/25 21:44:50 pace + * Initial revision + * + * Revision 2.3 91/02/05 17:05:44 mrt + * Changed to new Mach copyright + * [91/01/31 16:16:22 mrt] + * + * Revision 2.2 90/08/27 21:48:20 dbg + * Fix type declarations. + * [90/08/07 dbg] + * Created. + * [90/07/25 dbg] + * + */ +/* + * Author: David B. Golub, Carnegie Mellon University + * Date: 7/90 + */ +#include "param.h" +#include "proc.h" +#include <machine/db_machdep.h> /* type definitions */ + +/* + * Access unaligned data items on aligned (longword) + * boundaries. + */ + +extern void db_read_bytes(); /* machine-dependent */ +extern void db_write_bytes(); /* machine-dependent */ + +int db_extend[] = { /* table for sign-extending */ + 0, + 0xFFFFFF80, + 0xFFFF8000, + 0xFF800000 +}; + +db_expr_t +db_get_value(addr, size, is_signed) + db_addr_t addr; + register int size; + boolean_t is_signed; +{ + char data[sizeof(int)]; + register db_expr_t value; + register int i; + + db_read_bytes(addr, size, data); + + value = 0; +#if BYTE_MSF + for (i = 0; i < size; i++) +#else /* BYTE_LSF */ + for (i = size - 1; i >= 0; i--) +#endif + { + value = (value << 8) + (data[i] & 0xFF); + } + + if (size < 4) { + if (is_signed && (value & db_extend[size]) != 0) + value |= db_extend[size]; + } + return (value); +} + +void +db_put_value(addr, size, value) + db_addr_t addr; + register int size; + register db_expr_t value; +{ + char data[sizeof(int)]; + register int i; + +#if BYTE_MSF + for (i = size - 1; i >= 0; i--) +#else /* BYTE_LSF */ + for (i = 0; i < size; i++) +#endif + { + data[i] = value & 0xFF; + value >>= 8; + } + + db_write_bytes(addr, size, data); +} + |