/* * Mach Operating System * Copyright (c) 1991,1990 Carnegie Mellon University * All Rights Reserved. * * Permission to use, copy, modify and distribute this software and its * documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. * * $FreeBSD: src/sys/ddb/db_input.c,v 1.28.2.1 2002/03/08 16:37:10 yar Exp $ * $DragonFly: src/sys/ddb/db_input.c,v 1.4 2003/08/27 10:47:13 rob Exp $ */ /* * Author: David B. Golub, Carnegie Mellon University * Date: 7/90 */ #include #include #include #include #include /* * Character input and editing. */ /* * We don't track output position while editing input, * since input always ends with a new-line. We just * reset the line position at the end. */ static char * db_lbuf_start; /* start of input line buffer */ static char * db_lbuf_end; /* end of input line buffer */ static char * db_lc; /* current character */ static char * db_le; /* one past last character */ /* * Simple input line history support. */ static char db_lhistory[2048]; static int db_lhistlsize, db_lhistidx, db_lhistcur; static int db_lhist_nlines; #define CTRL(c) ((c) & 0x1f) #define BLANK ' ' #define BACKUP '\b' static int cnmaygetc (void); static void db_delete (int n, int bwd); static int db_inputchar (int c); static void db_putnchars (int c, int count); static void db_putstring (char *s, int count); void db_putstring(s, count) char *s; int count; { while (--count >= 0) cnputc(*s++); } void db_putnchars(c, count) int c; int count; { while (--count >= 0) cnputc(c); } /* * Delete N characters, forward or backward */ #define DEL_FWD 0 #define DEL_BWD 1 void db_delete(n, bwd) int n; int bwd; { char *p; if (bwd) { db_lc -= n; db_putnchars(BACKUP, n); } for (p = db_lc; p < db_le-n; p++) { *p = *(p+n); cnputc(*p); } db_putnchars(BLANK, n); db_putnchars(BACKUP, db_le - db_lc); db_le -= n; } /* returns TRUE at end-of-line */ int db_inputchar(c) int c; { static int escstate; if (escstate == 1) { /* ESC seen, look for [ or O */ if (c == '[' || c == 'O') escstate++; else escstate = 0; /* re-init state machine */ return (0); } else if (escstate == 2) { escstate = 0; /* * If a valid cursor key has been found, translate * into an emacs-style control key, and fall through. * Otherwise, drop off. */ switch (c) { case 'A': /* up */ c = CTRL('p'); break; case 'B': /* down */ c = CTRL('n'); break; case 'C': /* right */ c = CTRL('f'); break; case 'D': /* left */ c = CTRL('b'); break; default: return (0); } } switch (c) { case CTRL('['): escstate = 1; break; case CTRL('b'): /* back up one character */ if (db_lc > db_lbuf_start) { cnputc(BACKUP); db_lc--; } break; case CTRL('f'): /* forward one character */ if (db_lc < db_le) { cnputc(*db_lc); db_lc++; } break; case CTRL('a'): /* beginning of line */ while (db_lc > db_lbuf_start) { cnputc(BACKUP); db_lc--; } break; case CTRL('e'): /* end of line */ while (db_lc < db_le) { cnputc(*db_lc); db_lc++; } break; case CTRL('h'): case 0177: /* erase previous character */ if (db_lc > db_lbuf_start) db_delete(1, DEL_BWD); break; case CTRL('d'): /* erase next character */ if (db_lc < db_le) db_delete(1, DEL_FWD); break; case CTRL('u'): /* kill entire line: */ /* at first, delete to beginning of line */ if (db_lc > db_lbuf_start) db_delete(db_lc - db_lbuf_start, DEL_BWD); /* FALLTHROUGH */ case CTRL('k'): /* delete to end of line */ if (db_lc < db_le) db_delete(db_le - db_lc, DEL_FWD); break; case CTRL('t'): /* twiddle last 2 characters */ if (db_lc >= db_lbuf_start + 2) { c = db_lc[-2]; db_lc[-2] = db_lc[-1]; db_lc[-1] = c; cnputc(BACKUP); cnputc(BACKUP); cnputc(db_lc[-2]); cnputc(db_lc[-1]); } break; case CTRL('r'): db_putstring("^R\n", 3); redraw: if (db_le > db_lbuf_start) { db_putstring(db_lbuf_start, db_le - db_lbuf_start); db_putnchars(BACKUP, db_le - db_lc); } break; case CTRL('p'): /* Make previous history line the active one. */ if (db_lhistcur >= 0) { bcopy(db_lhistory + db_lhistcur * db_lhistlsize, db_lbuf_start, db_lhistlsize); db_lhistcur--; goto hist_redraw; } break; case CTRL('n'): /* Make next history line the active one. */ if (db_lhistcur < db_lhistidx - 1) { db_lhistcur += 2; bcopy(db_lhistory + db_lhistcur * db_lhistlsize, db_lbuf_start, db_lhistlsize); } else { /* * ^N through tail of history, reset the * buffer to zero length. */ *db_lbuf_start = '\0'; db_lhistcur = db_lhistidx; } hist_redraw: db_putnchars(BACKUP, db_le - db_lbuf_start); db_putnchars(BLANK, db_le - db_lbuf_start); db_putnchars(BACKUP, db_le - db_lbuf_start); db_le = index(db_lbuf_start, '\0'); if (db_le[-1] == '\r' || db_le[-1] == '\n') *--db_le = '\0'; db_lc = db_le; goto redraw; case -1: /* * eek! the console returned eof. * probably that means we HAVE no console.. we should try bail * XXX */ c = '\r'; case '\n': case '\r': *db_le++ = c; return (1); default: if (db_le == db_lbuf_end) { cnputc('\007'); } else if (c >= ' ' && c <= '~') { char *p; for (p = db_le; p > db_lc; p--) *p = *(p-1); *db_lc++ = c; db_le++; cnputc(c); db_putstring(db_lc, db_le - db_lc); db_putnchars(BACKUP, db_le - db_lc); } break; } return (0); } int cnmaygetc() { return (-1); } int db_readline(lstart, lsize) char * lstart; int lsize; { if (lsize != db_lhistlsize) { /* * (Re)initialize input line history. Throw away any * existing history. */ db_lhist_nlines = sizeof(db_lhistory) / lsize; db_lhistlsize = lsize; db_lhistidx = -1; } db_lhistcur = db_lhistidx; db_force_whitespace(); /* synch output position */ db_lbuf_start = lstart; db_lbuf_end = lstart + lsize; db_lc = lstart; db_le = lstart; while (!db_inputchar(cngetc())) continue; db_printf("\n"); /* synch output position */ *db_le = 0; if (db_le - db_lbuf_start > 1) { /* Maintain input line history for non-empty lines. */ if (++db_lhistidx == db_lhist_nlines) { /* Rotate history. */ ovbcopy(db_lhistory + db_lhistlsize, db_lhistory, db_lhistlsize * (db_lhist_nlines - 1)); db_lhistidx--; } bcopy(lstart, db_lhistory + db_lhistidx * db_lhistlsize, db_lhistlsize); } return (db_le - db_lbuf_start); } void db_check_interrupt() { int c; c = cnmaygetc(); switch (c) { case -1: /* no character */ return; case CTRL('c'): db_error((char *)0); /*NOTREACHED*/ case CTRL('s'): do { c = cnmaygetc(); if (c == CTRL('c')) db_error((char *)0); } while (c != CTRL('q')); break; default: /* drop on floor */ break; } }