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_input.c,v 1.22 1997/11/20 16:53:23 bde 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 37 #include <machine/cons.h> 38 39 #include <ddb/ddb.h> 40 #include <ddb/db_output.h> 41 42 /* 43 * Character input and editing. 44 */ 45 46 /* 47 * We don't track output position while editing input, 48 * since input always ends with a new-line. We just 49 * reset the line position at the end. 50 */ 51 static char * db_lbuf_start; /* start of input line buffer */ 52 static char * db_lbuf_end; /* end of input line buffer */ 53 static char * db_lc; /* current character */ 54 static char * db_le; /* one past last character */ 55 56 /* 57 * Simple input line history support. 58 */ 59 static char db_lhistory[2048]; 60 static int db_lhistlsize, db_lhistidx, db_lhistcur; 61 static int db_lhist_nlines; 62 63 #define CTRL(c) ((c) & 0x1f) 64 #define isspace(c) ((c) == ' ' || (c) == '\t') 65 #define BLANK ' ' 66 #define BACKUP '\b' 67 68 static int cnmaygetc __P((void)); 69 static void db_delete __P((int n, int bwd)); 70 static int db_inputchar __P((int c)); 71 static void db_putnchars __P((int c, int count)); 72 static void db_putstring __P((char *s, int count)); 73 74 void 75 db_putstring(s, count) 76 char *s; 77 int count; 78 { 79 while (--count >= 0) 80 cnputc(*s++); 81 } 82 83 void 84 db_putnchars(c, count) 85 int c; 86 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(n, bwd) 99 int n; 100 int bwd; 101 { 102 register char *p; 103 104 if (bwd) { 105 db_lc -= n; 106 db_putnchars(BACKUP, n); 107 } 108 for (p = db_lc; p < db_le-n; p++) { 109 *p = *(p+n); 110 cnputc(*p); 111 } 112 db_putnchars(BLANK, n); 113 db_putnchars(BACKUP, db_le - db_lc); 114 db_le -= n; 115 } 116 117 /* returns TRUE at end-of-line */ 118 int 119 db_inputchar(c) 120 int c; 121 { 122 static int escstate; 123 124 if (escstate == 1) { 125 /* ESC seen, look for [ or O */ 126 if (c == '[' || c == 'O') 127 escstate++; 128 else 129 escstate = 0; /* re-init state machine */ 130 return (0); 131 } else if (escstate == 2) { 132 escstate = 0; 133 /* 134 * If a valid cursor key has been found, translate 135 * into an emacs-style control key, and fall through. 136 * Otherwise, drop off. 137 */ 138 switch (c) { 139 case 'A': /* up */ 140 c = CTRL('p'); 141 break; 142 case 'B': /* down */ 143 c = CTRL('n'); 144 break; 145 case 'C': /* right */ 146 c = CTRL('f'); 147 break; 148 case 'D': /* left */ 149 c = CTRL('b'); 150 break; 151 default: 152 return (0); 153 } 154 } 155 156 switch (c) { 157 case CTRL('['): 158 escstate = 1; 159 break; 160 #if __i386__ && __FreeBSD__ 161 case 591: /* syscons's idea of left arrow key */ 162 #endif 163 case CTRL('b'): 164 /* back up one character */ 165 if (db_lc > db_lbuf_start) { 166 cnputc(BACKUP); 167 db_lc--; 168 } 169 break; 170 #if __i386__ && __FreeBSD__ 171 case 593: /* syscons's idea of right arrow key */ 172 #endif 173 case CTRL('f'): 174 /* forward one character */ 175 if (db_lc < db_le) { 176 cnputc(*db_lc); 177 db_lc++; 178 } 179 break; 180 case CTRL('a'): 181 /* beginning of line */ 182 while (db_lc > db_lbuf_start) { 183 cnputc(BACKUP); 184 db_lc--; 185 } 186 break; 187 case CTRL('e'): 188 /* end of line */ 189 while (db_lc < db_le) { 190 cnputc(*db_lc); 191 db_lc++; 192 } 193 break; 194 case CTRL('h'): 195 case 0177: 196 /* erase previous character */ 197 if (db_lc > db_lbuf_start) 198 db_delete(1, DEL_BWD); 199 break; 200 case CTRL('d'): 201 /* erase next character */ 202 if (db_lc < db_le) 203 db_delete(1, DEL_FWD); 204 break; 205 case CTRL('k'): 206 /* delete to end of line */ 207 if (db_lc < db_le) 208 db_delete(db_le - db_lc, DEL_FWD); 209 break; 210 case CTRL('t'): 211 /* twiddle last 2 characters */ 212 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 break; 222 case CTRL('r'): 223 db_putstring("^R\n", 3); 224 redraw: 225 if (db_le > db_lbuf_start) { 226 db_putstring(db_lbuf_start, db_le - db_lbuf_start); 227 db_putnchars(BACKUP, db_le - db_lc); 228 } 229 break; 230 #if __i386__ && __FreeBSD__ 231 case 588: /* syscons's idea of up arrow key */ 232 #endif 233 case CTRL('p'): 234 /* Make previous history line the active one. */ 235 if (db_lhistcur >= 0) { 236 bcopy(db_lhistory + db_lhistcur * db_lhistlsize, 237 db_lbuf_start, db_lhistlsize); 238 db_lhistcur--; 239 goto hist_redraw; 240 } 241 break; 242 #if __i386__ && __FreeBSD__ 243 case 596: /* syscons's idea of down arrow key */ 244 #endif 245 case CTRL('n'): 246 /* Make next history line the active one. */ 247 if (db_lhistcur < db_lhistidx - 1) { 248 db_lhistcur += 2; 249 bcopy(db_lhistory + db_lhistcur * db_lhistlsize, 250 db_lbuf_start, db_lhistlsize); 251 } else { 252 /* 253 * ^N through tail of history, reset the 254 * buffer to zero length. 255 */ 256 *db_lbuf_start = '\0'; 257 db_lhistcur = db_lhistidx; 258 } 259 260 hist_redraw: 261 db_putnchars(BACKUP, db_le - db_lbuf_start); 262 db_putnchars(BLANK, db_le - db_lbuf_start); 263 db_putnchars(BACKUP, db_le - db_lbuf_start); 264 db_le = index(db_lbuf_start, '\0'); 265 if (db_le[-1] == '\r' || db_le[-1] == '\n') 266 *--db_le = '\0'; 267 db_lc = db_le; 268 goto redraw; 269 270 case -1: 271 /* 272 * eek! the console returned eof. 273 * probably that means we HAVE no console.. we should try bail 274 * XXX 275 */ 276 c = '\r'; 277 case '\n': 278 case '\r': 279 *db_le++ = c; 280 return (1); 281 default: 282 if (db_le == db_lbuf_end) { 283 cnputc('\007'); 284 } 285 else if (c >= ' ' && c <= '~') { 286 register char *p; 287 288 for (p = db_le; p > db_lc; p--) 289 *p = *(p-1); 290 *db_lc++ = c; 291 db_le++; 292 cnputc(c); 293 db_putstring(db_lc, db_le - db_lc); 294 db_putnchars(BACKUP, db_le - db_lc); 295 } 296 break; 297 } 298 return (0); 299 } 300 301 int 302 cnmaygetc() 303 { 304 return (-1); 305 } 306 307 int 308 db_readline(lstart, lsize) 309 char * lstart; 310 int lsize; 311 { 312 if (lsize != db_lhistlsize) { 313 /* 314 * (Re)initialize input line history. Throw away any 315 * existing history. 316 */ 317 db_lhist_nlines = sizeof(db_lhistory) / lsize; 318 db_lhistlsize = lsize; 319 db_lhistidx = -1; 320 } 321 db_lhistcur = db_lhistidx; 322 323 db_force_whitespace(); /* synch output position */ 324 325 db_lbuf_start = lstart; 326 db_lbuf_end = lstart + lsize; 327 db_lc = lstart; 328 db_le = lstart; 329 330 while (!db_inputchar(cngetc())) 331 continue; 332 333 db_printf("\n"); /* synch output position */ 334 *db_le = 0; 335 336 if (db_le - db_lbuf_start > 1) { 337 /* Maintain input line history for non-empty lines. */ 338 if (++db_lhistidx == db_lhist_nlines) { 339 /* Rotate history. */ 340 ovbcopy(db_lhistory + db_lhistlsize, db_lhistory, 341 db_lhistlsize * (db_lhist_nlines - 1)); 342 db_lhistidx--; 343 } 344 bcopy(lstart, db_lhistory + db_lhistidx * db_lhistlsize, 345 db_lhistlsize); 346 } 347 348 return (db_le - db_lbuf_start); 349 } 350 351 void 352 db_check_interrupt() 353 { 354 register int c; 355 356 c = cnmaygetc(); 357 switch (c) { 358 case -1: /* no character */ 359 return; 360 361 case CTRL('c'): 362 db_error((char *)0); 363 /*NOTREACHED*/ 364 365 case CTRL('s'): 366 do { 367 c = cnmaygetc(); 368 if (c == CTRL('c')) 369 db_error((char *)0); 370 } while (c != CTRL('q')); 371 break; 372 373 default: 374 /* drop on floor */ 375 break; 376 } 377 } 378 379 /* called from kdb_trap in db_interface.c */ 380 void 381 cnpollc (flag) 382 int flag; 383 { 384 } 385