db_variables.c revision 2056
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 * $Id: db_variables.c,v 1.3 1993/11/25 01:30:13 wollman Exp $ 27 */ 28 29/* 30 * Author: David B. Golub, Carnegie Mellon University 31 * Date: 7/90 32 */ 33 34#include <sys/param.h> 35#include <sys/systm.h> 36#include <sys/proc.h> 37#include <ddb/ddb.h> 38 39#include <ddb/db_lex.h> 40#include <ddb/db_variables.h> 41 42void db_read_variable(struct db_variable *, db_expr_t *); 43static void db_write_variable(struct db_variable *, db_expr_t *); 44 45struct db_variable db_vars[] = { 46 { "radix", &db_radix, FCN_NULL }, 47 { "maxoff", (int *)&db_maxoff, FCN_NULL }, 48 { "maxwidth", &db_max_width, FCN_NULL }, 49 { "tabstops", &db_tab_stop_width, FCN_NULL }, 50}; 51struct db_variable *db_evars = db_vars + sizeof(db_vars)/sizeof(db_vars[0]); 52 53int 54db_find_variable(varp) 55 struct db_variable **varp; 56{ 57 int t; 58 struct db_variable *vp; 59 60 t = db_read_token(); 61 if (t == tIDENT) { 62 for (vp = db_vars; vp < db_evars; vp++) { 63 if (!strcmp(db_tok_string, vp->name)) { 64 *varp = vp; 65 return (1); 66 } 67 } 68 for (vp = db_regs; vp < db_eregs; vp++) { 69 if (!strcmp(db_tok_string, vp->name)) { 70 *varp = vp; 71 return (1); 72 } 73 } 74 } 75 db_error("Unknown variable\n"); 76 return (0); 77} 78 79int 80db_get_variable(valuep) 81 db_expr_t *valuep; 82{ 83 struct db_variable *vp; 84 85 if (!db_find_variable(&vp)) 86 return (0); 87 88 db_read_variable(vp, valuep); 89 90 return (1); 91} 92 93int 94db_set_variable(value) 95 db_expr_t value; 96{ 97 struct db_variable *vp; 98 99 if (!db_find_variable(&vp)) 100 return (0); 101 102 db_write_variable(vp, &value); 103 104 return (1); 105} 106 107 108void 109db_read_variable(vp, valuep) 110 struct db_variable *vp; 111 db_expr_t *valuep; 112{ 113 int (*func)() = vp->fcn; 114 115 if (func == FCN_NULL) 116 *valuep = *(vp->valuep); 117 else 118 (*func)(vp, valuep, DB_VAR_GET); 119} 120 121static void 122db_write_variable(vp, valuep) 123 struct db_variable *vp; 124 db_expr_t *valuep; 125{ 126 int (*func)() = vp->fcn; 127 128 if (func == FCN_NULL) 129 *(vp->valuep) = *valuep; 130 else 131 (*func)(vp, valuep, DB_VAR_SET); 132} 133 134void 135db_set_cmd(db_expr_t dummy1, int dummy2, db_expr_t dummy3, char *dummy4) 136{ 137 db_expr_t value; 138 int (*func)(); 139 struct db_variable *vp; 140 int t; 141 142 t = db_read_token(); 143 if (t != tDOLLAR) { 144 db_error("Unknown variable\n"); 145 return; 146 } 147 if (!db_find_variable(&vp)) { 148 db_error("Unknown variable\n"); 149 return; 150 } 151 152 t = db_read_token(); 153 if (t != tEQ) 154 db_unread_token(t); 155 156 if (!db_expression(&value)) { 157 db_error("No value\n"); 158 return; 159 } 160 if (db_read_token() != tEOL) { 161 db_error("?\n"); 162 } 163 164 db_write_variable(vp, &value); 165} 166