projects / dragonfly.git / blame
| Commit | Line | Data |
|---|---|---|
| 984263bc MD |
1 | /* |
| 2 | * Mach Operating System | |
| 3 | * Copyright (c) 1991,1990 Carnegie Mellon University | |
| 4 | * All Rights Reserved. | |
| 5 | * | |
| 6 | * Permission to use, copy, modify and distribute this software and its | |
| 7 | * documentation is hereby granted, provided that both the copyright | |
| 8 | * notice and this permission notice appear in all copies of the | |
| 9 | * software, derivative works or modified versions, and any portions | |
| 10 | * thereof, and that both notices appear in supporting documentation. | |
| 11 | * | |
| 12 | * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS | |
| 13 | * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR | |
| 14 | * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. | |
| 15 | * | |
| 16 | * Carnegie Mellon requests users of this software to return to | |
| 17 | * | |
| 18 | * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU | |
| 19 | * School of Computer Science | |
| 20 | * Carnegie Mellon University | |
| 21 | * Pittsburgh PA 15213-3890 | |
| 22 | * | |
| 23 | * any improvements or extensions that they make and grant Carnegie the | |
| 24 | * rights to redistribute these changes. | |
| 25 | * | |
| 26 | * $FreeBSD: src/sys/ddb/db_access.c,v 1.15 1999/08/28 00:41:04 peter Exp $ | |
| ad0290bd | 27 | * $DragonFly: src/sys/ddb/db_access.c,v 1.3 2003/07/26 14:18:51 rob Exp $ |
| 984263bc MD |
28 | */ |
| 29 | ||
| 30 | /* | |
| 31 | * Author: David B. Golub, Carnegie Mellon University | |
| 32 | * Date: 7/90 | |
| 33 | */ | |
| 34 | #include <sys/param.h> | |
| 35 | ||
| 36 | #include <ddb/ddb.h> | |
| 37 | #include <ddb/db_access.h> | |
| 38 | ||
| 39 | /* | |
| 40 | * Access unaligned data items on aligned (longword) | |
| 41 | * boundaries. | |
| 42 | */ | |
| 43 | ||
| 44 | static unsigned db_extend[] = { /* table for sign-extending */ | |
| 45 | 0, | |
| 46 | 0xFFFFFF80U, | |
| 47 | 0xFFFF8000U, | |
| 48 | 0xFF800000U | |
| 49 | }; | |
| 50 | ||
| 51 | db_expr_t | |
| 52 | db_get_value(addr, size, is_signed) | |
| 53 | db_addr_t addr; | |
| ad0290bd | 54 | int size; |
| 984263bc MD |
55 | boolean_t is_signed; |
| 56 | { | |
| 57 | char data[sizeof(int)]; | |
| ad0290bd RG |
58 | db_expr_t value; |
| 59 | int i; | |
| 984263bc MD |
60 | |
| 61 | db_read_bytes(addr, size, data); | |
| 62 | ||
| 63 | value = 0; | |
| 64 | #if BYTE_MSF | |
| 65 | for (i = 0; i < size; i++) | |
| 66 | #else /* BYTE_LSF */ | |
| 67 | for (i = size - 1; i >= 0; i--) | |
| 68 | #endif | |
| 69 | { | |
| 70 | value = (value << 8) + (data[i] & 0xFF); | |
| 71 | } | |
| 72 | ||
| 73 | if (size < 4) { | |
| 74 | if (is_signed && (value & db_extend[size]) != 0) | |
| 75 | value |= db_extend[size]; | |
| 76 | } | |
| 77 | return (value); | |
| 78 | } | |
| 79 | ||
| 80 | void | |
| 81 | db_put_value(addr, size, value) | |
| 82 | db_addr_t addr; | |
| ad0290bd RG |
83 | int size; |
| 84 | db_expr_t value; | |
| 984263bc MD |
85 | { |
| 86 | char data[sizeof(int)]; | |
| ad0290bd | 87 | int i; |
| 984263bc MD |
88 | |
| 89 | #if BYTE_MSF | |
| 90 | for (i = size - 1; i >= 0; i--) | |
| 91 | #else /* BYTE_LSF */ | |
| 92 | for (i = 0; i < size; i++) | |
| 93 | #endif | |
| 94 | { | |
| 95 | data[i] = value & 0xFF; | |
| 96 | value >>= 8; | |
| 97 | } | |
| 98 | ||
| 99 | db_write_bytes(addr, size, data); | |
| 100 | } | |
| 101 |