/* $NetBSD: db_input.c,v 1.26.64.1 2020/01/26 11:25:22 martin Exp $ */ /* * 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 "AS IS" * 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. * * Author: David B. Golub, Carnegie Mellon University * Date: 7/90 */ #include __KERNEL_RCSID(0, "$NetBSD: db_input.c,v 1.26.64.1 2020/01/26 11:25:22 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_ddbparam.h" #endif #include #include #include #include #ifndef DDB_HISTORY_SIZE #define DDB_HISTORY_SIZE 0 #endif /* DDB_HISTORY_SIZE */ /* * 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 */ #if DDB_HISTORY_SIZE != 0 static char db_history[DDB_HISTORY_SIZE]; /* start of history buffer */ static char *db_history_curr = db_history; /* start of current line */ static char *db_history_last = db_history; /* start of last line */ static char *db_history_prev = (char *) 0; /* start of previous line */ #endif #define CTRL(c) ((c) & 0x1f) #define isspace(c) ((c) == ' ' || (c) == '\t') #define BLANK ' ' #define BACKUP '\b' static int cnmaygetc(void); static void db_putstring(const char *, int); static void db_putnchars(int, int); static void db_delete(int, int); static void db_delete_line(void); static int db_inputchar(int); static void db_putstring(const char *s, int count) { while (--count >= 0) cnputc(*s++); } static void db_putnchars(int c, int count) { while (--count >= 0) cnputc(c); } /* * Delete N characters, forward or backward */ #define DEL_FWD 0 #define DEL_BWD 1 static void db_delete(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; } static void db_delete_line(void) { db_delete(db_le - db_lc, DEL_FWD); db_delete(db_lc - db_lbuf_start, DEL_BWD); db_le = db_lc = db_lbuf_start; } #if DDB_HISTORY_SIZE != 0 #define INC_DB_CURR() do { \ ++db_history_curr; \ if (db_history_curr > db_history + DDB_HISTORY_SIZE - 1) \ db_history_curr = db_history; \ } while (0) #define DEC_DB_CURR() do { \ --db_history_curr; \ if (db_history_curr < db_history) \ db_history_curr = db_history + DDB_HISTORY_SIZE - 1; \ } while (0) static inline void db_hist_put(int c) { KASSERT(&db_history[0] <= db_history_last); KASSERT(db_history_last <= &db_history[DDB_HISTORY_SIZE-1]); *db_history_last++ = c; if (db_history_last > &db_history[DDB_HISTORY_SIZE-1]) db_history_last = db_history; } #endif /* returns true at end-of-line */ static int db_inputchar(int c) { switch (c) { 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('k'): /* delete to end of line */ if (db_lc < db_le) db_delete(db_le - db_lc, DEL_FWD); break; case CTRL('u'): /* delete line */ db_delete_line(); break; case CTRL('t'): /* twiddle last 2 characters */ if (db_lc >= db_lbuf_start + 1) { if (db_lc < db_le) { c = db_lc[-1]; db_lc[-1] = db_lc[0]; db_lc[0] = c; cnputc(BACKUP); cnputc(db_lc[-1]); cnputc(db_lc[0]); db_lc++; } else 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; #if DDB_HISTORY_SIZE != 0 case CTRL('p'): DEC_DB_CURR(); while (db_history_curr != db_history_last) { DEC_DB_CURR(); if (*db_history_curr == '\0') break; } db_delete_line(); if (db_history_curr == db_history_last) { INC_DB_CURR(); db_le = db_lc = db_lbuf_start; } else { char *p; INC_DB_CURR(); for (p = db_history_curr, db_le = db_lbuf_start; *p; ) { *db_le++ = *p++; if (p >= db_history + DDB_HISTORY_SIZE) { p = db_history; } } db_lc = db_le; } db_putstring(db_lbuf_start, db_le - db_lbuf_start); break; case CTRL('n'): while (db_history_curr != db_history_last) { if (*db_history_curr == '\0') break; INC_DB_CURR(); } if (db_history_curr != db_history_last) { INC_DB_CURR(); db_delete_line(); if (db_history_curr != db_history_last) { char *p; for (p = db_history_curr, db_le = db_lbuf_start; *p;) { *db_le++ = *p++; if (p >= db_history + DDB_HISTORY_SIZE) { p = db_history; } } db_lc = db_le; } db_putstring(db_lbuf_start, db_le - db_lbuf_start); } break; #endif case CTRL('r'): db_putstring("^R\n", 3); 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 '\n': case '\r': #if DDB_HISTORY_SIZE != 0 /* Check if it same than previous line */ if (db_history_curr == db_history_prev) { char *pp, *pc; /* Is it unmodified */ for (pp = db_history_prev, pc = db_lbuf_start; pc != db_le && *pp; pp++, pc++) { if (*pp != *pc) break; if (++pp >= db_history + DDB_HISTORY_SIZE) { pp = db_history; } if (++pc >= db_history + DDB_HISTORY_SIZE) { pc = db_history; } } if (!*pp && pc == db_le) { /* Repeted previous line, not saved */ db_history_curr = db_history_last; *db_le++ = c; return (true); } } if (db_le != db_lbuf_start) { char *p; db_history_prev = db_history_last; for (p = db_lbuf_start; p != db_le; ) { db_hist_put(*p++); } db_hist_put(0); } db_history_curr = db_history_last; #endif *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 db_readline(char *lstart, int lsize) { 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_putchar('\n'); /* synch output position */ *db_le = 0; return (db_le - db_lbuf_start); } void db_check_interrupt(void) { 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); /*NOTREACHED*/ } } while (c != CTRL('q')); break; default: /* drop on floor */ break; } } static int cnmaygetc(void) { return (-1); }