1 /* $NetBSD: db_input.c,v 1.13 2000/03/30 11:31:27 augustss 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 + 2) { 204 c = db_lc[-2]; 205 db_lc[-2] = db_lc[-1]; 206 db_lc[-1] = c; 207 cnputc(BACKUP); 208 cnputc(BACKUP); 209 cnputc(db_lc[-2]); 210 cnputc(db_lc[-1]); 211 } 212 break; 213 #if DDB_HISTORY_SIZE != 0 214 case CTRL('p'): 215 DEC_DB_CURR(); 216 while (db_history_curr != db_history_last) { 217 DEC_DB_CURR(); 218 if (*db_history_curr == '\0') 219 break; 220 } 221 db_delete_line(); 222 if (db_history_curr == db_history_last) { 223 INC_DB_CURR(); 224 db_le = db_lc = db_lbuf_start; 225 } else { 226 char *p; 227 INC_DB_CURR(); 228 for (p = db_history_curr, db_le = db_lbuf_start; 229 *p; ) { 230 *db_le++ = *p++; 231 if (p == db_history + db_history_size) { 232 p = db_history; 233 } 234 } 235 db_lc = db_le; 236 } 237 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 238 break; 239 case CTRL('n'): 240 while (db_history_curr != db_history_last) { 241 if (*db_history_curr == '\0') 242 break; 243 INC_DB_CURR(); 244 } 245 if (db_history_curr != db_history_last) { 246 INC_DB_CURR(); 247 db_delete_line(); 248 if (db_history_curr != db_history_last) { 249 char *p; 250 for (p = db_history_curr, 251 db_le = db_lbuf_start; *p;) { 252 *db_le++ = *p++; 253 if (p == db_history + 254 db_history_size) { 255 p = db_history; 256 } 257 } 258 db_lc = db_le; 259 } 260 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 261 } 262 break; 263 #endif 264 case CTRL('r'): 265 db_putstring("^R\n", 3); 266 if (db_le > db_lbuf_start) { 267 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 268 db_putnchars(BACKUP, db_le - db_lc); 269 } 270 break; 271 case '\n': 272 case '\r': 273 #if DDB_HISTORY_SIZE != 0 274 /* Check if it same than previous line */ 275 if (db_history_curr == db_history_prev) { 276 char *pp, *pc; 277 278 /* Is it unmodified */ 279 for (pp = db_history_prev, pc = db_lbuf_start; 280 pc != db_le && *pp; pp++, pc++) { 281 if (*pp != *pc) 282 break; 283 if (++pp == db_history + db_history_size) { 284 pp = db_history; 285 } 286 if (++pc == db_history + db_history_size) { 287 pc = db_history; 288 } 289 } 290 if (!*pp && pc == db_le) { 291 /* Repeted previous line, not saved */ 292 db_history_curr = db_history_last; 293 *db_le++ = c; 294 return (TRUE); 295 } 296 } 297 if (db_le != db_lbuf_start) { 298 char *p; 299 db_history_prev = db_history_last; 300 for (p = db_lbuf_start; p != db_le; p++) { 301 *db_history_last++ = *p; 302 if (db_history_last == db_history + 303 db_history_size) { 304 db_history_last = db_history; 305 } 306 } 307 *db_history_last++ = '\0'; 308 } 309 db_history_curr = db_history_last; 310 #endif 311 *db_le++ = c; 312 return (1); 313 default: 314 if (db_le == db_lbuf_end) { 315 cnputc('\007'); 316 } 317 else if (c >= ' ' && c <= '~') { 318 char *p; 319 320 for (p = db_le; p > db_lc; p--) 321 *p = *(p-1); 322 *db_lc++ = c; 323 db_le++; 324 cnputc(c); 325 db_putstring(db_lc, db_le - db_lc); 326 db_putnchars(BACKUP, db_le - db_lc); 327 } 328 break; 329 } 330 return (0); 331 } 332 333 int 334 db_readline(lstart, lsize) 335 char * lstart; 336 int lsize; 337 { 338 db_force_whitespace(); /* synch output position */ 339 340 db_lbuf_start = lstart; 341 db_lbuf_end = lstart + lsize; 342 db_lc = lstart; 343 db_le = lstart; 344 345 while (!db_inputchar(cngetc())) 346 continue; 347 348 db_putchar('\n'); /* synch output position */ 349 350 *db_le = 0; 351 return (db_le - db_lbuf_start); 352 } 353 354 void 355 db_check_interrupt() 356 { 357 int c; 358 359 c = cnmaygetc(); 360 switch (c) { 361 case -1: /* no character */ 362 return; 363 364 case CTRL('c'): 365 db_error((char *)0); 366 /*NOTREACHED*/ 367 368 case CTRL('s'): 369 do { 370 c = cnmaygetc(); 371 if (c == CTRL('c')) { 372 db_error((char *)0); 373 /*NOTREACHED*/ 374 } 375 } while (c != CTRL('q')); 376 break; 377 378 default: 379 /* drop on floor */ 380 break; 381 } 382 } 383 384 static int 385 cnmaygetc () 386 { 387 return (-1); 388 } 389