1 /* $NetBSD: db_access.c,v 1.26 2019/09/12 17:09:00 ryo Exp $ */ 2 3 /* 4 * Mach Operating System 5 * Copyright (c) 1991,1990 Carnegie Mellon University 6 * All Rights Reserved. 7 * 8 * Permission to use, copy, modify and distribute this software and its 9 * documentation is hereby granted, provided that both the copyright 10 * notice and this permission notice appear in all copies of the 11 * software, derivative works or modified versions, and any portions 12 * thereof, and that both notices appear in supporting documentation. 13 * 14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 17 * 18 * Carnegie Mellon requests users of this software to return to 19 * 20 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 21 * School of Computer Science 22 * Carnegie Mellon University 23 * Pittsburgh PA 15213-3890 24 * 25 * any improvements or extensions that they make and grant Carnegie the 26 * rights to redistribute these changes. 27 * 28 * Author: David B. Golub, Carnegie Mellon University 29 * Date: 7/90 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: db_access.c,v 1.26 2019/09/12 17:09:00 ryo Exp $"); 34 35 #if defined(_KERNEL_OPT) 36 #include "opt_kgdb.h" 37 #endif 38 39 #include <sys/param.h> 40 #include <sys/proc.h> 41 #include <sys/endian.h> 42 43 #include <ddb/ddb.h> 44 45 /* 46 * Access unaligned data items on aligned (longword) 47 * boundaries. 48 * 49 * This file is shared by ddb, kgdb and crash(8). 50 */ 51 52 #if defined(DDB) || !defined(DDB) && !defined(KGDB) 53 #define _COMPILE_THIS 54 #endif 55 56 #if defined(_COMPILE_THIS) || defined(KGDB) && defined(SOFTWARE_SSTEP) 57 58 db_expr_t 59 db_get_value(db_addr_t addr, size_t size, bool is_signed) 60 { 61 char data[sizeof(db_expr_t)] __aligned(sizeof(db_expr_t)); 62 uintmax_t uvalue; 63 db_expr_t value; 64 size_t i; 65 66 db_read_bytes(addr, size, data); 67 68 uvalue = 0; 69 #if BYTE_ORDER == LITTLE_ENDIAN 70 for (i = size; i-- > 0;) 71 #else /* BYTE_ORDER == BIG_ENDIAN */ 72 for (i = 0; i < size; i++) 73 #endif /* BYTE_ORDER */ 74 uvalue = (uvalue << 8) + (data[i] & 0xFF); 75 76 value = (db_expr_t)uvalue; 77 78 if (size < sizeof(db_expr_t) && is_signed 79 && (value & ((db_expr_t)1 << (8*size - 1)))) { 80 value |= (unsigned long)~(db_expr_t)0 << (8*size - 1); 81 } 82 return (value); 83 } 84 85 quad_t 86 db_get_qvalue(db_addr_t addr, size_t size, bool is_signed) 87 { 88 uint64_t data; 89 90 if (size < sizeof(uint64_t)) { 91 if (is_signed) 92 return db_get_value(addr, size, true); 93 return (uint32_t)db_get_value(addr, size, false); 94 } 95 96 if (size != sizeof(data)) { 97 db_error("unnsupported size\n"); 98 /*NOTREACHED*/ 99 } 100 101 db_read_bytes(addr, sizeof(data), (char *)&data); 102 return data; 103 } 104 105 void 106 db_put_value(db_addr_t addr, size_t size, db_expr_t value) 107 { 108 char data[sizeof(db_expr_t)] __aligned(sizeof(db_expr_t)); 109 size_t i; 110 111 #if BYTE_ORDER == LITTLE_ENDIAN 112 for (i = 0; i < size; i++) 113 #else /* BYTE_ORDER == BIG_ENDIAN */ 114 for (i = size; i-- > 0;) 115 #endif /* BYTE_ORDER */ 116 { 117 data[i] = value & 0xFF; 118 value >>= 8; 119 } 120 121 db_write_bytes(addr, size, data); 122 } 123 124 #endif /* _COMPILE_THIS || KGDB && SOFTWARE_SSTEP */ 125 126 #ifdef _COMPILE_THIS 127 128 void * 129 db_read_ptr(const char *name) 130 { 131 db_expr_t val; 132 void *p; 133 134 if (!db_value_of_name(name, &val)) { 135 db_printf("db_read_ptr: cannot find `%s'\n", name); 136 db_error(NULL); 137 /* NOTREACHED */ 138 } 139 db_read_bytes((db_addr_t)val, sizeof(p), (char *)&p); 140 return p; 141 } 142 143 int 144 db_read_int(const char *name) 145 { 146 db_expr_t val; 147 int p; 148 149 if (!db_value_of_name(name, &val)) { 150 db_printf("db_read_int: cannot find `%s'\n", name); 151 db_error(NULL); 152 /* NOTREACHED */ 153 } 154 db_read_bytes((db_addr_t)val, sizeof(p), (char *)&p); 155 return p; 156 } 157 158 #endif /* _COMPILE_THIS */ 159