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 /* 27 * Author: David B. Golub, Carnegie Mellon University 28 * Date: 7/90 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include <sys/param.h> 35 #include <sys/kdb.h> 36 37 #include <ddb/ddb.h> 38 #include <ddb/db_access.h> 39 40 /* 41 * Access unaligned data items on aligned (longword) 42 * boundaries. 43 */ 44 45 static unsigned db_extend[] = { /* table for sign-extending */ 46 0, 47 0xFFFFFF80U, 48 0xFFFF8000U, 49 0xFF800000U 50 }; 51 52 #ifndef BYTE_MSF 53 #define BYTE_MSF 0 54 #endif 55 56 db_expr_t 57 db_get_value(db_addr_t addr, int size, bool is_signed) 58 { 59 char data[sizeof(u_int64_t)]; 60 db_expr_t value; 61 int i; 62 63 if (db_read_bytes(addr, size, data) != 0) { 64 db_printf("*** error reading from address %llx ***\n", 65 (long long)addr); 66 kdb_reenter(); 67 } 68 69 value = 0; 70 #if BYTE_MSF 71 for (i = 0; i < size; i++) 72 #else /* BYTE_LSF */ 73 for (i = size - 1; i >= 0; i--) 74 #endif 75 { 76 value = (value << 8) + (data[i] & 0xFF); 77 } 78 79 if (size < 4) { 80 if (is_signed && (value & db_extend[size]) != 0) 81 value |= db_extend[size]; 82 } 83 return (value); 84 } 85 86 void 87 db_put_value(db_addr_t addr, int size, db_expr_t value) 88 { 89 char data[sizeof(int)]; 90 int i; 91 92 #if BYTE_MSF 93 for (i = size - 1; i >= 0; i--) 94 #else /* BYTE_LSF */ 95 for (i = 0; i < size; i++) 96 #endif 97 { 98 data[i] = value & 0xFF; 99 value >>= 8; 100 } 101 102 if (db_write_bytes(addr, size, data) != 0) { 103 db_printf("*** error writing to address %llx ***\n", 104 (long long)addr); 105 kdb_reenter(); 106 } 107 } 108