1 /* $OpenBSD: db_input.c,v 1.18 2019/11/06 07:30:08 mpi Exp $ */ 2 /* $NetBSD: db_input.c,v 1.7 1996/02/05 01:57:02 christos Exp $ */ 3 4 /* 5 * Mach Operating System 6 * Copyright (c) 1993,1992,1991,1990 Carnegie Mellon University 7 * All Rights Reserved. 8 * 9 * Permission to use, copy, modify and distribute this software and its 10 * documentation is hereby granted, provided that both the copyright 11 * notice and this permission notice appear in all copies of the 12 * software, derivative works or modified versions, and any portions 13 * thereof, and that both notices appear in supporting documentation. 14 * 15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 16 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 17 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 18 * 19 * Carnegie Mellon requests users of this software to return to 20 * 21 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 22 * School of Computer Science 23 * Carnegie Mellon University 24 * Pittsburgh PA 15213-3890 25 * 26 * any improvements or extensions that they make and grant Carnegie Mellon 27 * the rights to redistribute these changes. 28 * 29 * Author: David B. Golub, Carnegie Mellon University 30 * Date: 7/90 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 36 #include <machine/db_machdep.h> 37 38 #include <ddb/db_var.h> 39 #include <ddb/db_output.h> 40 #include <ddb/db_sym.h> 41 #include <ddb/db_extern.h> 42 43 #include <dev/cons.h> 44 45 /* 46 * Character input and editing. 47 */ 48 49 void db_putstring(char *, int); 50 void db_putnchars(int, int); 51 void db_delete(int, int); 52 void db_delete_line(void); 53 int db_inputchar(int); 54 55 /* 56 * We don't track output position while editing input, 57 * since input always ends with a new-line. We just 58 * reset the line position at the end. 59 */ 60 char * db_lbuf_start; /* start of input line buffer */ 61 char * db_lbuf_end; /* end of input line buffer */ 62 char * db_lc; /* current character */ 63 char * db_le; /* one past last character */ 64 #if DB_HISTORY_SIZE != 0 65 char db_history[DB_HISTORY_SIZE]; /* start of history buffer */ 66 int db_history_size = DB_HISTORY_SIZE;/* size of history buffer */ 67 char * db_history_curr = db_history; /* start of current line */ 68 char * db_history_last = db_history; /* start of last line */ 69 char * db_history_prev = (char *) 0; /* start of previous line */ 70 #endif 71 72 73 #define CTRL(c) ((c) & 0x1f) 74 #define isspace(c) ((c) == ' ' || (c) == '\t') 75 #define BLANK ' ' 76 #define BACKUP '\b' 77 78 void 79 db_putstring(char *s, int count) 80 { 81 while (--count >= 0) 82 cnputc(*s++); 83 } 84 85 void 86 db_putnchars(int c, int count) 87 { 88 while (--count >= 0) 89 cnputc(c); 90 } 91 92 /* 93 * Delete N characters, forward or backward 94 */ 95 #define DEL_FWD 0 96 #define DEL_BWD 1 97 void 98 db_delete(int n, int bwd) 99 { 100 char *p; 101 102 if (bwd) { 103 db_lc -= n; 104 db_putnchars(BACKUP, n); 105 } 106 for (p = db_lc; p < db_le-n; p++) { 107 *p = *(p+n); 108 cnputc(*p); 109 } 110 db_putnchars(BLANK, n); 111 db_putnchars(BACKUP, db_le - db_lc); 112 db_le -= n; 113 } 114 115 void 116 db_delete_line(void) 117 { 118 db_delete(db_le - db_lc, DEL_FWD); 119 db_delete(db_lc - db_lbuf_start, DEL_BWD); 120 db_le = db_lc = db_lbuf_start; 121 } 122 123 #if DB_HISTORY_SIZE != 0 124 #define INC_DB_CURR() \ 125 do { \ 126 db_history_curr++; \ 127 if (db_history_curr > \ 128 db_history + db_history_size - 1) \ 129 db_history_curr = db_history; \ 130 } while (0) 131 #define DEC_DB_CURR() \ 132 do { \ 133 db_history_curr--; \ 134 if (db_history_curr < db_history) \ 135 db_history_curr = db_history + \ 136 db_history_size - 1; \ 137 } while (0) 138 #endif 139 140 /* returns `1' at end-of-line */ 141 int 142 db_inputchar(int c) 143 { 144 switch (c) { 145 case CTRL('b'): 146 /* back up one character */ 147 if (db_lc > db_lbuf_start) { 148 cnputc(BACKUP); 149 db_lc--; 150 } 151 break; 152 case CTRL('f'): 153 /* forward one character */ 154 if (db_lc < db_le) { 155 cnputc(*db_lc); 156 db_lc++; 157 } 158 break; 159 case CTRL('a'): 160 /* beginning of line */ 161 while (db_lc > db_lbuf_start) { 162 cnputc(BACKUP); 163 db_lc--; 164 } 165 break; 166 case CTRL('e'): 167 /* end of line */ 168 while (db_lc < db_le) { 169 cnputc(*db_lc); 170 db_lc++; 171 } 172 break; 173 case CTRL('w'): 174 /* erase word back */ 175 while (db_lc > db_lbuf_start && db_lc[-1] != BLANK) 176 db_delete(1, DEL_BWD); 177 break; 178 case CTRL('h'): 179 case 0177: 180 /* erase previous character */ 181 if (db_lc > db_lbuf_start) 182 db_delete(1, DEL_BWD); 183 break; 184 case CTRL('d'): 185 /* erase next character */ 186 if (db_lc < db_le) 187 db_delete(1, DEL_FWD); 188 break; 189 case CTRL('k'): 190 /* delete to end of line */ 191 if (db_lc < db_le) 192 db_delete(db_le - db_lc, DEL_FWD); 193 break; 194 case CTRL('u'): 195 /* delete line */ 196 db_delete_line(); 197 break; 198 case CTRL('t'): 199 /* twiddle last 2 characters */ 200 if (db_lc >= db_lbuf_start + 2) { 201 c = db_lc[-2]; 202 db_lc[-2] = db_lc[-1]; 203 db_lc[-1] = c; 204 cnputc(BACKUP); 205 cnputc(BACKUP); 206 cnputc(db_lc[-2]); 207 cnputc(db_lc[-1]); 208 } 209 break; 210 #if DB_HISTORY_SIZE != 0 211 case CTRL('p'): 212 DEC_DB_CURR(); 213 while (db_history_curr != db_history_last) { 214 DEC_DB_CURR(); 215 if (*db_history_curr == '\0') 216 break; 217 } 218 db_delete_line(); 219 if (db_history_curr == db_history_last) { 220 INC_DB_CURR(); 221 db_le = db_lc = db_lbuf_start; 222 } else { 223 char *p; 224 INC_DB_CURR(); 225 for (p = db_history_curr, db_le = db_lbuf_start;*p; ) { 226 *db_le++ = *p++; 227 if (p == db_history + db_history_size) 228 p = db_history; 229 } 230 db_lc = db_le; 231 } 232 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 233 break; 234 case CTRL('n'): 235 while (db_history_curr != db_history_last) { 236 if (*db_history_curr == '\0') 237 break; 238 INC_DB_CURR(); 239 } 240 if (db_history_curr != db_history_last) { 241 INC_DB_CURR(); 242 db_delete_line(); 243 if (db_history_curr != db_history_last) { 244 char *p; 245 for (p = db_history_curr, 246 db_le = db_lbuf_start; *p;) { 247 *db_le++ = *p++; 248 if (p == db_history + db_history_size) 249 p = db_history; 250 } 251 db_lc = db_le; 252 } 253 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 254 } 255 break; 256 #endif 257 case CTRL('r'): 258 db_putstring("^R\n", 3); 259 if (db_le > db_lbuf_start) { 260 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 261 db_putnchars(BACKUP, db_le - db_lc); 262 } 263 break; 264 case '\n': 265 case '\r': 266 #if DB_HISTORY_SIZE != 0 267 /* 268 * Check whether current line is the same 269 * as previous saved line. If it is, don`t 270 * save it. 271 */ 272 if (db_history_curr == db_history_prev) { 273 char *pp, *pc; 274 275 /* 276 * Is it the same? 277 */ 278 for (pp = db_history_prev, pc = db_lbuf_start; 279 pc != db_le && *pp; ) { 280 if (*pp != *pc) 281 break; 282 if (++pp == db_history + db_history_size) 283 pp = db_history; 284 pc++; 285 } 286 if (!*pp && pc == db_le) { 287 /* 288 * Repeated previous line. Don`t save. 289 */ 290 db_history_curr = db_history_last; 291 *db_le++ = c; 292 return 1; 293 } 294 } 295 if (db_le != db_lbuf_start) { 296 char *p; 297 db_history_prev = db_history_last; 298 for (p = db_lbuf_start; p != db_le; p++) { 299 *db_history_last++ = *p; 300 if (db_history_last == 301 db_history + db_history_size) 302 db_history_last = db_history; 303 } 304 *db_history_last++ = '\0'; 305 if (db_history_last == db_history + db_history_size) 306 db_history_last = db_history; 307 } 308 db_history_curr = db_history_last; 309 #endif 310 *db_le++ = c; 311 return 1; 312 default: 313 if (db_le == db_lbuf_end) { 314 cnputc('\007'); 315 } 316 else if (c >= ' ' && c <= '~') { 317 char *p; 318 319 for (p = db_le; p > db_lc; p--) 320 *p = *(p-1); 321 *db_lc++ = c; 322 db_le++; 323 cnputc(c); 324 db_putstring(db_lc, db_le - db_lc); 325 db_putnchars(BACKUP, db_le - db_lc); 326 } 327 break; 328 } 329 return 0; 330 } 331 332 int 333 db_readline(char *lstart, int lsize) 334 { 335 db_force_whitespace(); /* synch output position */ 336 337 db_lbuf_start = lstart; 338 db_lbuf_end = lstart + lsize - 1; 339 db_lc = lstart; 340 db_le = lstart; 341 342 while (!db_inputchar(cngetc())) 343 continue; 344 345 db_putchar('\n'); /* synch output position */ 346 347 *db_le = 0; 348 return (db_le - db_lbuf_start); 349 } 350