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_output.c,v 1.26 1999/08/28 00:41:09 peter Exp $ 27 * $DragonFly: src/sys/ddb/db_output.c,v 1.6 2004/09/03 08:50:47 eirikn Exp $ 28 */ 29 30 /* 31 * Author: David B. Golub, Carnegie Mellon University 32 * Date: 7/90 33 */ 34 35 /* 36 * Printf and character output for debugger. 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/cons.h> 42 43 #include <machine/stdarg.h> 44 45 #include <ddb/ddb.h> 46 #include <ddb/db_output.h> 47 48 /* 49 * Character output - tracks position in line. 50 * To do this correctly, we should know how wide 51 * the output device is - then we could zero 52 * the line position when the output device wraps 53 * around to the start of the next line. 54 * 55 * Instead, we count the number of spaces printed 56 * since the last printing character so that we 57 * don't print trailing spaces. This avoids most 58 * of the wraparounds. 59 */ 60 static int db_output_position = 0; /* output column */ 61 static int db_last_non_space = 0; /* last non-space character */ 62 db_expr_t db_tab_stop_width = 8; /* how wide are tab stops? */ 63 #define NEXT_TAB(i) \ 64 ((((i) + db_tab_stop_width) / db_tab_stop_width) * db_tab_stop_width) 65 db_expr_t db_max_width = 79; /* output line width */ 66 67 static void db_putchar (int c, void *arg); 68 69 /* 70 * Force pending whitespace. 71 */ 72 void 73 db_force_whitespace() 74 { 75 int last_print, next_tab; 76 77 last_print = db_last_non_space; 78 while (last_print < db_output_position) { 79 next_tab = NEXT_TAB(last_print); 80 if (next_tab <= db_output_position) { 81 while (last_print < next_tab) { /* DON'T send a tab!!! */ 82 cnputc(' '); 83 last_print++; 84 } 85 } 86 else { 87 cnputc(' '); 88 last_print++; 89 } 90 } 91 db_last_non_space = db_output_position; 92 } 93 94 /* 95 * Output character. Buffer whitespace. 96 */ 97 static void 98 db_putchar(c, arg) 99 int c; /* character to output */ 100 void * arg; 101 { 102 if (c > ' ' && c <= '~') { 103 /* 104 * Printing character. 105 * If we have spaces to print, print them first. 106 * Use tabs if possible. 107 */ 108 db_force_whitespace(); 109 cnputc(c); 110 db_output_position++; 111 db_last_non_space = db_output_position; 112 } 113 else if (c == '\n') { 114 /* Newline */ 115 cnputc(c); 116 db_output_position = 0; 117 db_last_non_space = 0; 118 db_check_interrupt(); 119 } 120 else if (c == '\r') { 121 /* Return */ 122 cnputc(c); 123 db_output_position = 0; 124 db_last_non_space = 0; 125 db_check_interrupt(); 126 } 127 else if (c == '\t') { 128 /* assume tabs every 8 positions */ 129 db_output_position = NEXT_TAB(db_output_position); 130 } 131 else if (c == ' ') { 132 /* space */ 133 db_output_position++; 134 } 135 else if (c == '\007') { 136 /* bell */ 137 cnputc(c); 138 } 139 /* other characters are assumed non-printing */ 140 } 141 142 /* 143 * Return output position 144 */ 145 int 146 db_print_position() 147 { 148 return (db_output_position); 149 } 150 151 /* 152 * Printing 153 */ 154 void 155 db_printf(const char *fmt, ...) 156 { 157 __va_list listp; 158 159 __va_start(listp, fmt); 160 kvprintf (fmt, db_putchar, NULL, db_radix, listp); 161 __va_end(listp); 162 } 163 164 int db_indent; 165 166 void 167 db_iprintf(const char *fmt,...) 168 { 169 int i; 170 __va_list listp; 171 172 for (i = db_indent; i >= 8; i -= 8) 173 db_printf("\t"); 174 while (--i >= 0) 175 db_printf(" "); 176 __va_start(listp, fmt); 177 kvprintf (fmt, db_putchar, NULL, db_radix, listp); 178 __va_end(listp); 179 } 180 181 /* 182 * End line if too long. 183 */ 184 void 185 db_end_line() 186 { 187 if (db_output_position >= db_max_width) 188 db_printf("\n"); 189 } 190 191 /* 192 * Simple pager 193 */ 194 int 195 db_more(int *nl) 196 { 197 ++*nl; 198 if (*nl == 20) { 199 int c; 200 201 db_printf("--More--"); 202 c = cngetc(); 203 db_printf("\r"); 204 /* 205 * A whole screenfull or just one line? 206 */ 207 switch (c) { 208 case '\n': /* just one line */ 209 *nl = 19; 210 break; 211 case ' ': 212 *nl = 0; /* another screenfull */ 213 break; 214 default: /* exit */ 215 db_printf("\n"); 216 return(-1); 217 } 218 } 219 return(0); 220 } 221 222