1 /* $NetBSD: db_input.c,v 1.14 2000/07/28 16:33:39 jhawk 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 "opt_ddbparam.h" 33 34 #include <sys/param.h> 35 #include <sys/proc.h> 36 37 #include <machine/db_machdep.h> 38 39 #include <ddb/db_output.h> 40 #include <ddb/db_command.h> 41 #include <ddb/db_sym.h> 42 #include <ddb/db_extern.h> 43 44 #include <dev/cons.h> 45 46 #ifndef DDB_HISTORY_SIZE 47 #define DDB_HISTORY_SIZE 0 48 #endif /* DDB_HISTORY_SIZE */ 49 50 /* 51 * Character input and editing. 52 */ 53 54 /* 55 * We don't track output position while editing input, 56 * since input always ends with a new-line. We just 57 * reset the line position at the end. 58 */ 59 char * db_lbuf_start; /* start of input line buffer */ 60 char * db_lbuf_end; /* end of input line buffer */ 61 char * db_lc; /* current character */ 62 char * db_le; /* one past last character */ 63 #if DDB_HISTORY_SIZE != 0 64 char db_history[DDB_HISTORY_SIZE]; /* start of history buffer */ 65 int db_history_size = DDB_HISTORY_SIZE;/* size of history buffer */ 66 char * db_history_curr = db_history; /* start of current line */ 67 char * db_history_last = db_history; /* start of last line */ 68 char * db_history_prev = (char *) 0; /* start of previous line */ 69 #endif 70 71 72 #define CTRL(c) ((c) & 0x1f) 73 #define isspace(c) ((c) == ' ' || (c) == '\t') 74 #define BLANK ' ' 75 #define BACKUP '\b' 76 77 static int cnmaygetc __P((void)); 78 79 void 80 db_putstring(s, count) 81 char *s; 82 int count; 83 { 84 while (--count >= 0) 85 cnputc(*s++); 86 } 87 88 void 89 db_putnchars(c, count) 90 int c; 91 int count; 92 { 93 while (--count >= 0) 94 cnputc(c); 95 } 96 97 /* 98 * Delete N characters, forward or backward 99 */ 100 #define DEL_FWD 0 101 #define DEL_BWD 1 102 void 103 db_delete(n, bwd) 104 int n; 105 int bwd; 106 { 107 char *p; 108 109 if (bwd) { 110 db_lc -= n; 111 db_putnchars(BACKUP, n); 112 } 113 for (p = db_lc; p < db_le-n; p++) { 114 *p = *(p+n); 115 cnputc(*p); 116 } 117 db_putnchars(BLANK, n); 118 db_putnchars(BACKUP, db_le - db_lc); 119 db_le -= n; 120 } 121 122 void 123 db_delete_line() 124 { 125 db_delete(db_le - db_lc, DEL_FWD); 126 db_delete(db_lc - db_lbuf_start, DEL_BWD); 127 db_le = db_lc = db_lbuf_start; 128 } 129 130 #if DDB_HISTORY_SIZE != 0 131 #define INC_DB_CURR() \ 132 do { \ 133 db_history_curr++; \ 134 if (db_history_curr > \ 135 db_history + db_history_size - 1) \ 136 db_history_curr = db_history; \ 137 } while (0) 138 #define DEC_DB_CURR() \ 139 do { \ 140 db_history_curr--; \ 141 if (db_history_curr < db_history) \ 142 db_history_curr = db_history + \ 143 db_history_size - 1; \ 144 } while (0) 145 #endif 146 147 /* returns TRUE at end-of-line */ 148 int 149 db_inputchar(c) 150 int c; 151 { 152 switch (c) { 153 case CTRL('b'): 154 /* back up one character */ 155 if (db_lc > db_lbuf_start) { 156 cnputc(BACKUP); 157 db_lc--; 158 } 159 break; 160 case CTRL('f'): 161 /* forward one character */ 162 if (db_lc < db_le) { 163 cnputc(*db_lc); 164 db_lc++; 165 } 166 break; 167 case CTRL('a'): 168 /* beginning of line */ 169 while (db_lc > db_lbuf_start) { 170 cnputc(BACKUP); 171 db_lc--; 172 } 173 break; 174 case CTRL('e'): 175 /* end of line */ 176 while (db_lc < db_le) { 177 cnputc(*db_lc); 178 db_lc++; 179 } 180 break; 181 case CTRL('h'): 182 case 0177: 183 /* erase previous character */ 184 if (db_lc > db_lbuf_start) 185 db_delete(1, DEL_BWD); 186 break; 187 case CTRL('d'): 188 /* erase next character */ 189 if (db_lc < db_le) 190 db_delete(1, DEL_FWD); 191 break; 192 case CTRL('k'): 193 /* delete to end of line */ 194 if (db_lc < db_le) 195 db_delete(db_le - db_lc, DEL_FWD); 196 break; 197 case CTRL('u'): 198 /* delete line */ 199 db_delete_line(); 200 break; 201 case CTRL('t'): 202 /* twiddle last 2 characters */ 203 if (db_lc >= db_lbuf_start + 1) { 204 if (db_lc < db_le) { 205 c = db_lc[-1]; 206 db_lc[-1] = db_lc[0]; 207 db_lc[0] = c; 208 cnputc(BACKUP); 209 cnputc(db_lc[-1]); 210 cnputc(db_lc[0]); 211 db_lc++; 212 } else if (db_lc >= db_lbuf_start + 2) { 213 c = db_lc[-2]; 214 db_lc[-2] = db_lc[-1]; 215 db_lc[-1] = c; 216 cnputc(BACKUP); 217 cnputc(BACKUP); 218 cnputc(db_lc[-2]); 219 cnputc(db_lc[-1]); 220 } 221 } 222 break; 223 #if DDB_HISTORY_SIZE != 0 224 case CTRL('p'): 225 DEC_DB_CURR(); 226 while (db_history_curr != db_history_last) { 227 DEC_DB_CURR(); 228 if (*db_history_curr == '\0') 229 break; 230 } 231 db_delete_line(); 232 if (db_history_curr == db_history_last) { 233 INC_DB_CURR(); 234 db_le = db_lc = db_lbuf_start; 235 } else { 236 char *p; 237 INC_DB_CURR(); 238 for (p = db_history_curr, db_le = db_lbuf_start; 239 *p; ) { 240 *db_le++ = *p++; 241 if (p == db_history + db_history_size) { 242 p = db_history; 243 } 244 } 245 db_lc = db_le; 246 } 247 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 248 break; 249 case CTRL('n'): 250 while (db_history_curr != db_history_last) { 251 if (*db_history_curr == '\0') 252 break; 253 INC_DB_CURR(); 254 } 255 if (db_history_curr != db_history_last) { 256 INC_DB_CURR(); 257 db_delete_line(); 258 if (db_history_curr != db_history_last) { 259 char *p; 260 for (p = db_history_curr, 261 db_le = db_lbuf_start; *p;) { 262 *db_le++ = *p++; 263 if (p == db_history + 264 db_history_size) { 265 p = db_history; 266 } 267 } 268 db_lc = db_le; 269 } 270 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 271 } 272 break; 273 #endif 274 case CTRL('r'): 275 db_putstring("^R\n", 3); 276 if (db_le > db_lbuf_start) { 277 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 278 db_putnchars(BACKUP, db_le - db_lc); 279 } 280 break; 281 case '\n': 282 case '\r': 283 #if DDB_HISTORY_SIZE != 0 284 /* Check if it same than previous line */ 285 if (db_history_curr == db_history_prev) { 286 char *pp, *pc; 287 288 /* Is it unmodified */ 289 for (pp = db_history_prev, pc = db_lbuf_start; 290 pc != db_le && *pp; pp++, pc++) { 291 if (*pp != *pc) 292 break; 293 if (++pp == db_history + db_history_size) { 294 pp = db_history; 295 } 296 if (++pc == db_history + db_history_size) { 297 pc = db_history; 298 } 299 } 300 if (!*pp && pc == db_le) { 301 /* Repeted previous line, not saved */ 302 db_history_curr = db_history_last; 303 *db_le++ = c; 304 return (TRUE); 305 } 306 } 307 if (db_le != db_lbuf_start) { 308 char *p; 309 db_history_prev = db_history_last; 310 for (p = db_lbuf_start; p != db_le; p++) { 311 *db_history_last++ = *p; 312 if (db_history_last == db_history + 313 db_history_size) { 314 db_history_last = db_history; 315 } 316 } 317 *db_history_last++ = '\0'; 318 } 319 db_history_curr = db_history_last; 320 #endif 321 *db_le++ = c; 322 return (1); 323 default: 324 if (db_le == db_lbuf_end) { 325 cnputc('\007'); 326 } 327 else if (c >= ' ' && c <= '~') { 328 char *p; 329 330 for (p = db_le; p > db_lc; p--) 331 *p = *(p-1); 332 *db_lc++ = c; 333 db_le++; 334 cnputc(c); 335 db_putstring(db_lc, db_le - db_lc); 336 db_putnchars(BACKUP, db_le - db_lc); 337 } 338 break; 339 } 340 return (0); 341 } 342 343 int 344 db_readline(lstart, lsize) 345 char * lstart; 346 int lsize; 347 { 348 db_force_whitespace(); /* synch output position */ 349 350 db_lbuf_start = lstart; 351 db_lbuf_end = lstart + lsize; 352 db_lc = lstart; 353 db_le = lstart; 354 355 while (!db_inputchar(cngetc())) 356 continue; 357 358 db_putchar('\n'); /* synch output position */ 359 360 *db_le = 0; 361 return (db_le - db_lbuf_start); 362 } 363 364 void 365 db_check_interrupt() 366 { 367 int c; 368 369 c = cnmaygetc(); 370 switch (c) { 371 case -1: /* no character */ 372 return; 373 374 case CTRL('c'): 375 db_error((char *)0); 376 /*NOTREACHED*/ 377 378 case CTRL('s'): 379 do { 380 c = cnmaygetc(); 381 if (c == CTRL('c')) { 382 db_error((char *)0); 383 /*NOTREACHED*/ 384 } 385 } while (c != CTRL('q')); 386 break; 387 388 default: 389 /* drop on floor */ 390 break; 391 } 392 } 393 394 static int 395 cnmaygetc () 396 { 397 return (-1); 398 } 399