in_ifadown() was only cleaning up the route table on the originating cpu,
[dragonfly.git] / bin / ed / main.c
1 /* main.c: This file contains the main control and user-interface routines
2    for the ed line editor. */
3 /*-
4  * Copyright (c) 1993 Andrew Moore, Talke Studio.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * @(#) Copyright (c) 1993 Andrew Moore, Talke Studio. All rights reserved.
29  * @(#)main.c,v 1.1 1994/02/01 00:34:42 alm Exp
30  * $FreeBSD: src/bin/ed/main.c,v 1.14.2.4 2001/08/01 02:36:03 obrien Exp $
31  * $DragonFly: src/bin/ed/main.c,v 1.8 2005/03/09 02:38:51 drhodus Exp $
32  */
33
34 /*
35  * CREDITS
36  *
37  *      This program is based on the editor algorithm described in
38  *      Brian W. Kernighan and P. J. Plauger's book "Software Tools
39  *      in Pascal," Addison-Wesley, 1981.
40  *
41  *      The buffering algorithm is attributed to Rodney Ruddock of
42  *      the University of Guelph, Guelph, Ontario.
43  *
44  *      The cbc.c encryption code is adapted from
45  *      the bdes program by Matt Bishop of Dartmouth College,
46  *      Hanover, NH.
47  *
48  */
49
50 #include <sys/types.h>
51
52 #include <sys/ioctl.h>
53 #include <sys/wait.h>
54 #include <ctype.h>
55 #include <locale.h>
56 #include <pwd.h>
57 #include <setjmp.h>
58
59 #include "ed.h"
60
61
62 #ifdef _POSIX_SOURCE
63 sigjmp_buf env;
64 #else
65 jmp_buf env;
66 #endif
67
68 /* static buffers */
69 char stdinbuf[1];               /* stdin buffer */
70 char *shcmd;                    /* shell command buffer */
71 int shcmdsz;                    /* shell command buffer size */
72 int shcmdi;                     /* shell command buffer index */
73 char *ibuf;                     /* ed command-line buffer */
74 int ibufsz;                     /* ed command-line buffer size */
75 char *ibufp;                    /* pointer to ed command-line buffer */
76
77 /* global flags */
78 int des = 0;                    /* if set, use crypt(3) for i/o */
79 int garrulous = 0;              /* if set, print all error messages */
80 int isbinary;                   /* if set, buffer contains ASCII NULs */
81 int isglobal;                   /* if set, doing a global command */
82 int modified;                   /* if set, buffer modified since last write */
83 int mutex = 0;                  /* if set, signals set "sigflags" */
84 int red = 0;                    /* if set, restrict shell/directory access */
85 int scripted = 0;               /* if set, suppress diagnostics */
86 int sigflags = 0;               /* if set, signals received while mutex set */
87 int sigactive = 0;              /* if set, signal handlers are enabled */
88
89 char old_filename[PATH_MAX] = "";       /* default filename */
90 long current_addr;              /* current address in editor buffer */
91 long addr_last;                 /* last address in editor buffer */
92 int lineno;                     /* script line number */
93 const char *prompt;             /* command-line prompt */
94 const char *dps = "*";          /* default command-line prompt */
95
96 const char usage[] = "usage: %s [-] [-sx] [-p string] [name]\n";
97
98 /* ed: line editor */
99 int
100 main(int argc, char **argv)
101 {
102         int c, n;
103         long status = 0;
104 #if __GNUC__
105         /* Avoid longjmp clobbering */
106         (void) &argc;
107         (void) &argv;
108 #endif
109
110         setlocale(LC_ALL, "");
111
112         red = (n = strlen(argv[0])) > 2 && argv[0][n - 3] == 'r';
113 top:
114         while ((c = getopt(argc, argv, "p:sx")) != -1)
115                 switch(c) {
116                 case 'p':                               /* set prompt */
117                         prompt = optarg;
118                         break;
119                 case 's':                               /* run script */
120                         scripted = 1;
121                         break;
122                 case 'x':                               /* use crypt */
123 #ifdef DES
124                         des = get_keyword();
125                         break;
126 #else
127                         fprintf(stderr, "crypt unavailable\n?\n");
128 #endif
129                         break;
130
131                 default:
132                         fprintf(stderr, usage, argv[0]);
133                         exit(1);
134                 }
135         argv += optind;
136         argc -= optind;
137         if (argc && **argv == '-') {
138                 scripted = 1;
139                 if (argc > 1) {
140                         optind = 1;
141                         goto top;
142                 }
143                 argv++;
144                 argc--;
145         }
146         /* assert: reliable signals! */
147 #ifdef SIGWINCH
148         handle_winch(SIGWINCH);
149         if (isatty(0)) signal(SIGWINCH, handle_winch);
150 #endif
151         signal(SIGHUP, signal_hup);
152         signal(SIGQUIT, SIG_IGN);
153         signal(SIGINT, signal_int);
154 #ifdef _POSIX_SOURCE
155         if ((status = sigsetjmp(env, 1)))
156 #else
157         if ((status = setjmp(env)))
158 #endif
159         {
160                 fputs("\n?\n", stderr);
161                 sprintf(errmsg, "interrupt");
162         } else {
163                 init_buffers();
164                 sigactive = 1;                  /* enable signal handlers */
165                 if (argc && **argv && is_legal_filename(*argv)) {
166                         if (read_file(*argv, 0) < 0 && !isatty(0))
167                                 quit(2);
168                         else if (**argv != '!')
169                                 if (strlcpy(old_filename, *argv, sizeof(old_filename))
170                                     >= sizeof(old_filename))
171                                         quit(2);
172                 } else if (argc) {
173                         fputs("?\n", stderr);
174                         if (**argv == '\0')
175                                 sprintf(errmsg, "invalid filename");
176                         if (!isatty(0))
177                                 quit(2);
178                 }
179         }
180         for (;;) {
181                 if (status < 0 && garrulous)
182                         fprintf(stderr, "%s\n", errmsg);
183                 if (prompt) {
184                         printf("%s", prompt);
185                         fflush(stdout);
186                 }
187                 if ((n = get_tty_line()) < 0) {
188                         status = ERR;
189                         continue;
190                 } else if (n == 0) {
191                         if (modified && !scripted) {
192                                 fputs("?\n", stderr);
193                                 sprintf(errmsg, "warning: file modified");
194                                 if (!isatty(0)) {
195                                         fprintf(stderr, garrulous ?
196                                             "script, line %d: %s\n" :
197                                             "", lineno, errmsg);
198                                         quit(2);
199                                 }
200                                 clearerr(stdin);
201                                 modified = 0;
202                                 status = EMOD;
203                                 continue;
204                         } else
205                                 quit(0);
206                 } else if (ibuf[n - 1] != '\n') {
207                         /* discard line */
208                         sprintf(errmsg, "unexpected end-of-file");
209                         clearerr(stdin);
210                         status = ERR;
211                         continue;
212                 }
213                 isglobal = 0;
214                 if ((status = extract_addr_range()) >= 0 &&
215                     (status = exec_command()) >= 0)
216                         if (!status ||
217                             (status = display_lines(current_addr, current_addr,
218                                 status)) >= 0)
219                                 continue;
220                 switch (status) {
221                 case EOF:
222                         quit(0);
223                 case EMOD:
224                         modified = 0;
225                         fputs("?\n", stderr);           /* give warning */
226                         sprintf(errmsg, "warning: file modified");
227                         if (!isatty(0)) {
228                                 fprintf(stderr, garrulous ?
229                                     "script, line %d: %s\n" :
230                                     "", lineno, errmsg);
231                                 quit(2);
232                         }
233                         break;
234                 case FATAL:
235                         if (!isatty(0))
236                                 fprintf(stderr, garrulous ?
237                                     "script, line %d: %s\n" : "",
238                                     lineno, errmsg);
239                         else
240                                 fprintf(stderr, garrulous ? "%s\n" : "",
241                                     errmsg);
242                         quit(3);
243                 default:
244                         fputs("?\n", stderr);
245                         if (!isatty(0)) {
246                                 fprintf(stderr, garrulous ?
247                                     "script, line %d: %s\n" : "",
248                                     lineno, errmsg);
249                                 quit(2);
250                         }
251                         break;
252                 }
253         }
254         /*NOTREACHED*/
255 }
256
257 long first_addr, second_addr, addr_cnt;
258
259 /* extract_addr_range: get line addresses from the command buffer until an
260    illegal address is seen; return status */
261 int
262 extract_addr_range(void)
263 {
264         long addr;
265
266         addr_cnt = 0;
267         first_addr = second_addr = current_addr;
268         while ((addr = next_addr()) >= 0) {
269                 addr_cnt++;
270                 first_addr = second_addr;
271                 second_addr = addr;
272                 if (*ibufp != ',' && *ibufp != ';')
273                         break;
274                 else if (*ibufp++ == ';')
275                         current_addr = addr;
276         }
277         if ((addr_cnt = min(addr_cnt, 2)) == 1 || second_addr != addr)
278                 first_addr = second_addr;
279         return (addr == ERR) ? ERR : 0;
280 }
281
282
283 #define SKIP_BLANKS() while (isspace((unsigned char)*ibufp) && *ibufp != '\n') ibufp++
284
285 #define MUST_BE_FIRST() \
286         if (!first) { sprintf(errmsg, "invalid address"); return ERR; }
287
288 /*  next_addr: return the next line address in the command buffer */
289 long
290 next_addr(void)
291 {
292         char *hd;
293         long addr = current_addr;
294         long n;
295         int first = 1;
296         int c;
297
298         SKIP_BLANKS();
299         for (hd = ibufp;; first = 0)
300                 switch (c = *ibufp) {
301                 case '+':
302                 case '\t':
303                 case ' ':
304                 case '-':
305                 case '^':
306                         ibufp++;
307                         SKIP_BLANKS();
308                         if (isdigit((unsigned char)*ibufp)) {
309                                 STRTOL(n, ibufp);
310                                 addr += (c == '-' || c == '^') ? -n : n;
311                         } else if (!isspace((unsigned char)c))
312                                 addr += (c == '-' || c == '^') ? -1 : 1;
313                         break;
314                 case '0': case '1': case '2':
315                 case '3': case '4': case '5':
316                 case '6': case '7': case '8': case '9':
317                         MUST_BE_FIRST();
318                         STRTOL(addr, ibufp);
319                         break;
320                 case '.':
321                 case '$':
322                         MUST_BE_FIRST();
323                         ibufp++;
324                         addr = (c == '.') ? current_addr : addr_last;
325                         break;
326                 case '/':
327                 case '?':
328                         MUST_BE_FIRST();
329                         if ((addr = get_matching_node_addr(
330                             get_compiled_pattern(), c == '/')) < 0)
331                                 return ERR;
332                         else if (c == *ibufp)
333                                 ibufp++;
334                         break;
335                 case '\'':
336                         MUST_BE_FIRST();
337                         ibufp++;
338                         if ((addr = get_marked_node_addr(*ibufp++)) < 0)
339                                 return ERR;
340                         break;
341                 case '%':
342                 case ',':
343                 case ';':
344                         if (first) {
345                                 ibufp++;
346                                 addr_cnt++;
347                                 second_addr = (c == ';') ? current_addr : 1;
348                                 addr = addr_last;
349                                 break;
350                         }
351                         /* FALL THROUGH */
352                 default:
353                         if (ibufp == hd)
354                                 return EOF;
355                         else if (addr < 0 || addr_last < addr) {
356                                 sprintf(errmsg, "invalid address");
357                                 return ERR;
358                         } else
359                                 return addr;
360                 }
361         /* NOTREACHED */
362 }
363
364
365 #ifdef BACKWARDS
366 /* GET_THIRD_ADDR: get a legal address from the command buffer */
367 #define GET_THIRD_ADDR(addr) \
368 { \
369         long ol1, ol2; \
370 \
371         ol1 = first_addr, ol2 = second_addr; \
372         if (extract_addr_range() < 0) \
373                 return ERR; \
374         else if (addr_cnt == 0) { \
375                 sprintf(errmsg, "destination expected"); \
376                 return ERR; \
377         } else if (second_addr < 0 || addr_last < second_addr) { \
378                 sprintf(errmsg, "invalid address"); \
379                 return ERR; \
380         } \
381         addr = second_addr; \
382         first_addr = ol1, second_addr = ol2; \
383 }
384 #else   /* BACKWARDS */
385 /* GET_THIRD_ADDR: get a legal address from the command buffer */
386 #define GET_THIRD_ADDR(addr) \
387 { \
388         long ol1, ol2; \
389 \
390         ol1 = first_addr, ol2 = second_addr; \
391         if (extract_addr_range() < 0) \
392                 return ERR; \
393         if (second_addr < 0 || addr_last < second_addr) { \
394                 sprintf(errmsg, "invalid address"); \
395                 return ERR; \
396         } \
397         addr = second_addr; \
398         first_addr = ol1, second_addr = ol2; \
399 }
400 #endif
401
402
403 /* GET_COMMAND_SUFFIX: verify the command suffix in the command buffer */
404 #define GET_COMMAND_SUFFIX() { \
405         int done = 0; \
406         do { \
407                 switch(*ibufp) { \
408                 case 'p': \
409                         gflag |= GPR, ibufp++; \
410                         break; \
411                 case 'l': \
412                         gflag |= GLS, ibufp++; \
413                         break; \
414                 case 'n': \
415                         gflag |= GNP, ibufp++; \
416                         break; \
417                 default: \
418                         done++; \
419                 } \
420         } while (!done); \
421         if (*ibufp++ != '\n') { \
422                 sprintf(errmsg, "invalid command suffix"); \
423                 return ERR; \
424         } \
425 }
426
427
428 /* sflags */
429 #define SGG 001         /* complement previous global substitute suffix */
430 #define SGP 002         /* complement previous print suffix */
431 #define SGR 004         /* use last regex instead of last pat */
432 #define SGF 010         /* repeat last substitution */
433
434 int patlock = 0;        /* if set, pattern not freed by get_compiled_pattern() */
435
436 long rows = 22;         /* scroll length: ws_row - 2 */
437
438 /* exec_command: execute the next command in command buffer; return print
439    request, if any */
440 int
441 exec_command(void)
442 {
443         static pattern_t *pat = NULL;
444         static int sgflag = 0;
445         static long sgnum = 0;
446
447         pattern_t *tpat;
448         char *fnp;
449         int gflag = 0;
450         int sflags = 0;
451         long addr = 0;
452         int n = 0;
453         int c;
454
455         SKIP_BLANKS();
456         switch(c = *ibufp++) {
457         case 'a':
458                 GET_COMMAND_SUFFIX();
459                 if (!isglobal) clear_undo_stack();
460                 if (append_lines(second_addr) < 0)
461                         return ERR;
462                 break;
463         case 'c':
464                 if (check_addr_range(current_addr, current_addr) < 0)
465                         return ERR;
466                 GET_COMMAND_SUFFIX();
467                 if (!isglobal) clear_undo_stack();
468                 if (delete_lines(first_addr, second_addr) < 0 ||
469                     append_lines(current_addr) < 0)
470                         return ERR;
471                 break;
472         case 'd':
473                 if (check_addr_range(current_addr, current_addr) < 0)
474                         return ERR;
475                 GET_COMMAND_SUFFIX();
476                 if (!isglobal) clear_undo_stack();
477                 if (delete_lines(first_addr, second_addr) < 0)
478                         return ERR;
479                 else if ((addr = INC_MOD(current_addr, addr_last)) != 0)
480                         current_addr = addr;
481                 break;
482         case 'e':
483                 if (modified && !scripted)
484                         return EMOD;
485                 /* fall through */
486         case 'E':
487                 if (addr_cnt > 0) {
488                         sprintf(errmsg, "unexpected address");
489                         return ERR;
490                 } else if (!isspace((unsigned char)*ibufp)) {
491                         sprintf(errmsg, "unexpected command suffix");
492                         return ERR;
493                 } else if ((fnp = get_filename()) == NULL)
494                         return ERR;
495                 GET_COMMAND_SUFFIX();
496                 if (delete_lines(1, addr_last) < 0)
497                         return ERR;
498                 clear_undo_stack();
499                 if (close_sbuf() < 0)
500                         return ERR;
501                 else if (open_sbuf() < 0)
502                         return FATAL;
503                 if (*fnp && *fnp != '!') strcpy(old_filename, fnp);
504 #ifdef BACKWARDS
505                 if (*fnp == '\0' && *old_filename == '\0') {
506                         sprintf(errmsg, "no current filename");
507                         return ERR;
508                 }
509 #endif
510                 if (read_file(*fnp ? fnp : old_filename, 0) < 0)
511                         return ERR;
512                 clear_undo_stack();
513                 modified = 0;
514                 u_current_addr = u_addr_last = -1;
515                 break;
516         case 'f':
517                 if (addr_cnt > 0) {
518                         sprintf(errmsg, "unexpected address");
519                         return ERR;
520                 } else if (!isspace((unsigned char)*ibufp)) {
521                         sprintf(errmsg, "unexpected command suffix");
522                         return ERR;
523                 } else if ((fnp = get_filename()) == NULL)
524                         return ERR;
525                 else if (*fnp == '!') {
526                         sprintf(errmsg, "invalid redirection");
527                         return ERR;
528                 }
529                 GET_COMMAND_SUFFIX();
530                 if (*fnp) strcpy(old_filename, fnp);
531                 printf("%s\n", strip_escapes(old_filename));
532                 break;
533         case 'g':
534         case 'v':
535         case 'G':
536         case 'V':
537                 if (isglobal) {
538                         sprintf(errmsg, "cannot nest global commands");
539                         return ERR;
540                 } else if (check_addr_range(1, addr_last) < 0)
541                         return ERR;
542                 else if (build_active_list(c == 'g' || c == 'G') < 0)
543                         return ERR;
544                 else if ((n = (c == 'G' || c == 'V')))
545                         GET_COMMAND_SUFFIX();
546                 isglobal++;
547                 if (exec_global(n, gflag) < 0)
548                         return ERR;
549                 break;
550         case 'h':
551                 if (addr_cnt > 0) {
552                         sprintf(errmsg, "unexpected address");
553                         return ERR;
554                 }
555                 GET_COMMAND_SUFFIX();
556                 if (*errmsg) fprintf(stderr, "%s\n", errmsg);
557                 break;
558         case 'H':
559                 if (addr_cnt > 0) {
560                         sprintf(errmsg, "unexpected address");
561                         return ERR;
562                 }
563                 GET_COMMAND_SUFFIX();
564                 if ((garrulous = 1 - garrulous) && *errmsg)
565                         fprintf(stderr, "%s\n", errmsg);
566                 break;
567         case 'i':
568                 if (second_addr == 0) {
569                         sprintf(errmsg, "invalid address");
570                         return ERR;
571                 }
572                 GET_COMMAND_SUFFIX();
573                 if (!isglobal) clear_undo_stack();
574                 if (append_lines(second_addr - 1) < 0)
575                         return ERR;
576                 break;
577         case 'j':
578                 if (check_addr_range(current_addr, current_addr + 1) < 0)
579                         return ERR;
580                 GET_COMMAND_SUFFIX();
581                 if (!isglobal) clear_undo_stack();
582                 if (first_addr != second_addr &&
583                     join_lines(first_addr, second_addr) < 0)
584                         return ERR;
585                 break;
586         case 'k':
587                 c = *ibufp++;
588                 if (second_addr == 0) {
589                         sprintf(errmsg, "invalid address");
590                         return ERR;
591                 }
592                 GET_COMMAND_SUFFIX();
593                 if (mark_line_node(get_addressed_line_node(second_addr), c) < 0)
594                         return ERR;
595                 break;
596         case 'l':
597                 if (check_addr_range(current_addr, current_addr) < 0)
598                         return ERR;
599                 GET_COMMAND_SUFFIX();
600                 if (display_lines(first_addr, second_addr, gflag | GLS) < 0)
601                         return ERR;
602                 gflag = 0;
603                 break;
604         case 'm':
605                 if (check_addr_range(current_addr, current_addr) < 0)
606                         return ERR;
607                 GET_THIRD_ADDR(addr);
608                 if (first_addr <= addr && addr < second_addr) {
609                         sprintf(errmsg, "invalid destination");
610                         return ERR;
611                 }
612                 GET_COMMAND_SUFFIX();
613                 if (!isglobal) clear_undo_stack();
614                 if (move_lines(addr) < 0)
615                         return ERR;
616                 break;
617         case 'n':
618                 if (check_addr_range(current_addr, current_addr) < 0)
619                         return ERR;
620                 GET_COMMAND_SUFFIX();
621                 if (display_lines(first_addr, second_addr, gflag | GNP) < 0)
622                         return ERR;
623                 gflag = 0;
624                 break;
625         case 'p':
626                 if (check_addr_range(current_addr, current_addr) < 0)
627                         return ERR;
628                 GET_COMMAND_SUFFIX();
629                 if (display_lines(first_addr, second_addr, gflag | GPR) < 0)
630                         return ERR;
631                 gflag = 0;
632                 break;
633         case 'P':
634                 if (addr_cnt > 0) {
635                         sprintf(errmsg, "unexpected address");
636                         return ERR;
637                 }
638                 GET_COMMAND_SUFFIX();
639                 prompt = prompt ? NULL : optarg ? optarg : dps;
640                 break;
641         case 'q':
642         case 'Q':
643                 if (addr_cnt > 0) {
644                         sprintf(errmsg, "unexpected address");
645                         return ERR;
646                 }
647                 GET_COMMAND_SUFFIX();
648                 gflag =  (modified && !scripted && c == 'q') ? EMOD : EOF;
649                 break;
650         case 'r':
651                 if (!isspace((unsigned char)*ibufp)) {
652                         sprintf(errmsg, "unexpected command suffix");
653                         return ERR;
654                 } else if (addr_cnt == 0)
655                         second_addr = addr_last;
656                 if ((fnp = get_filename()) == NULL)
657                         return ERR;
658                 GET_COMMAND_SUFFIX();
659                 if (!isglobal) clear_undo_stack();
660                 if (*old_filename == '\0' && *fnp != '!')
661                         strcpy(old_filename, fnp);
662 #ifdef BACKWARDS
663                 if (*fnp == '\0' && *old_filename == '\0') {
664                         sprintf(errmsg, "no current filename");
665                         return ERR;
666                 }
667 #endif
668                 if ((addr = read_file(*fnp ? fnp : old_filename, second_addr)) < 0)
669                         return ERR;
670                 else if (addr && addr != addr_last)
671                         modified = 1;
672                 break;
673         case 's':
674                 do {
675                         switch(*ibufp) {
676                         case '\n':
677                                 sflags |=SGF;
678                                 break;
679                         case 'g':
680                                 sflags |= SGG;
681                                 ibufp++;
682                                 break;
683                         case 'p':
684                                 sflags |= SGP;
685                                 ibufp++;
686                                 break;
687                         case 'r':
688                                 sflags |= SGR;
689                                 ibufp++;
690                                 break;
691                         case '0': case '1': case '2': case '3': case '4':
692                         case '5': case '6': case '7': case '8': case '9':
693                                 STRTOL(sgnum, ibufp);
694                                 sflags |= SGF;
695                                 sgflag &= ~GSG;         /* override GSG */
696                                 break;
697                         default:
698                                 if (sflags) {
699                                         sprintf(errmsg, "invalid command suffix");
700                                         return ERR;
701                                 }
702                         }
703                 } while (sflags && *ibufp != '\n');
704                 if (sflags && !pat) {
705                         sprintf(errmsg, "no previous substitution");
706                         return ERR;
707                 } else if (sflags & SGG)
708                         sgnum = 0;              /* override numeric arg */
709                 if (*ibufp != '\n' && *(ibufp + 1) == '\n') {
710                         sprintf(errmsg, "invalid pattern delimiter");
711                         return ERR;
712                 }
713                 tpat = pat;
714                 SPL1();
715                 if ((!sflags || (sflags & SGR)) &&
716                     (tpat = get_compiled_pattern()) == NULL) {
717                         SPL0();
718                         return ERR;
719                 } else if (tpat != pat) {
720                         if (pat) {
721                                 regfree(pat);
722                                 free(pat);
723                         }
724                         pat = tpat;
725                         patlock = 1;            /* reserve pattern */
726                 }
727                 SPL0();
728                 if (!sflags && extract_subst_tail(&sgflag, &sgnum) < 0)
729                         return ERR;
730                 else if (isglobal)
731                         sgflag |= GLB;
732                 else
733                         sgflag &= ~GLB;
734                 if (sflags & SGG)
735                         sgflag ^= GSG;
736                 if (sflags & SGP)
737                         sgflag ^= GPR, sgflag &= ~(GLS | GNP);
738                 do {
739                         switch(*ibufp) {
740                         case 'p':
741                                 sgflag |= GPR, ibufp++;
742                                 break;
743                         case 'l':
744                                 sgflag |= GLS, ibufp++;
745                                 break;
746                         case 'n':
747                                 sgflag |= GNP, ibufp++;
748                                 break;
749                         default:
750                                 n++;
751                         }
752                 } while (!n);
753                 if (check_addr_range(current_addr, current_addr) < 0)
754                         return ERR;
755                 GET_COMMAND_SUFFIX();
756                 if (!isglobal) clear_undo_stack();
757                 if (search_and_replace(pat, sgflag, sgnum) < 0)
758                         return ERR;
759                 break;
760         case 't':
761                 if (check_addr_range(current_addr, current_addr) < 0)
762                         return ERR;
763                 GET_THIRD_ADDR(addr);
764                 GET_COMMAND_SUFFIX();
765                 if (!isglobal) clear_undo_stack();
766                 if (copy_lines(addr) < 0)
767                         return ERR;
768                 break;
769         case 'u':
770                 if (addr_cnt > 0) {
771                         sprintf(errmsg, "unexpected address");
772                         return ERR;
773                 }
774                 GET_COMMAND_SUFFIX();
775                 if (pop_undo_stack() < 0)
776                         return ERR;
777                 break;
778         case 'w':
779         case 'W':
780                 if ((n = *ibufp) == 'q' || n == 'Q') {
781                         gflag = EOF;
782                         ibufp++;
783                 }
784                 if (!isspace((unsigned char)*ibufp)) {
785                         sprintf(errmsg, "unexpected command suffix");
786                         return ERR;
787                 } else if ((fnp = get_filename()) == NULL)
788                         return ERR;
789                 if (addr_cnt == 0 && !addr_last)
790                         first_addr = second_addr = 0;
791                 else if (check_addr_range(1, addr_last) < 0)
792                         return ERR;
793                 GET_COMMAND_SUFFIX();
794                 if (*old_filename == '\0' && *fnp != '!')
795                         strcpy(old_filename, fnp);
796 #ifdef BACKWARDS
797                 if (*fnp == '\0' && *old_filename == '\0') {
798                         sprintf(errmsg, "no current filename");
799                         return ERR;
800                 }
801 #endif
802                 if ((addr = write_file(*fnp ? fnp : old_filename,
803                     (c == 'W') ? "a" : "w", first_addr, second_addr)) < 0)
804                         return ERR;
805                 else if (addr == addr_last)
806                         modified = 0;
807                 else if (modified && !scripted && n == 'q')
808                         gflag = EMOD;
809                 break;
810         case 'x':
811                 if (addr_cnt > 0) {
812                         sprintf(errmsg, "unexpected address");
813                         return ERR;
814                 }
815                 GET_COMMAND_SUFFIX();
816 #ifdef DES
817                 des = get_keyword();
818 #else
819                 sprintf(errmsg, "crypt unavailable");
820                 return ERR;
821 #endif
822         case 'z':
823 #ifdef BACKWARDS
824                 if (check_addr_range(first_addr = 1, current_addr + 1) < 0)
825 #else
826                 if (check_addr_range(first_addr = 1, current_addr + !isglobal) < 0)
827 #endif
828                         return ERR;
829                 else if ('0' < *ibufp && *ibufp <= '9')
830                         STRTOL(rows, ibufp);
831                 GET_COMMAND_SUFFIX();
832                 if (display_lines(second_addr, min(addr_last,
833                     second_addr + rows), gflag) < 0)
834                         return ERR;
835                 gflag = 0;
836                 break;
837         case '=':
838                 GET_COMMAND_SUFFIX();
839                 printf("%ld\n", addr_cnt ? second_addr : addr_last);
840                 break;
841         case '!':
842                 if (addr_cnt > 0) {
843                         sprintf(errmsg, "unexpected address");
844                         return ERR;
845                 } else if ((sflags = get_shell_command()) < 0)
846                         return ERR;
847                 GET_COMMAND_SUFFIX();
848                 if (sflags) printf("%s\n", shcmd + 1);
849                 system(shcmd + 1);
850                 if (!scripted) printf("!\n");
851                 break;
852         case '\n':
853 #ifdef BACKWARDS
854                 if (check_addr_range(first_addr = 1, current_addr + 1) < 0
855 #else
856                 if (check_addr_range(first_addr = 1, current_addr + !isglobal) < 0
857 #endif
858                  || display_lines(second_addr, second_addr, 0) < 0)
859                         return ERR;
860                 break;
861         default:
862                 sprintf(errmsg, "unknown command");
863                 return ERR;
864         }
865         return gflag;
866 }
867
868
869 /* check_addr_range: return status of address range check */
870 int
871 check_addr_range(long n, long m)
872 {
873         if (addr_cnt == 0) {
874                 first_addr = n;
875                 second_addr = m;
876         }
877         if (first_addr > second_addr || 1 > first_addr ||
878             second_addr > addr_last) {
879                 sprintf(errmsg, "invalid address");
880                 return ERR;
881         }
882         return 0;
883 }
884
885
886 /* get_matching_node_addr: return the address of the next line matching a
887    pattern in a given direction.  wrap around begin/end of editor buffer if
888    necessary */
889 long
890 get_matching_node_addr(pattern_t *pat, int dir)
891 {
892         char *s;
893         long n = current_addr;
894         line_t *lp;
895
896         if (!pat) return ERR;
897         do {
898                if ((n = dir ? INC_MOD(n, addr_last) : DEC_MOD(n, addr_last))) {
899                         lp = get_addressed_line_node(n);
900                         if ((s = get_sbuf_line(lp)) == NULL)
901                                 return ERR;
902                         if (isbinary)
903                                 NUL_TO_NEWLINE(s, lp->len);
904                         if (!regexec(pat, s, 0, NULL, 0))
905                                 return n;
906                }
907         } while (n != current_addr);
908         sprintf(errmsg, "no match");
909         return  ERR;
910 }
911
912
913 /* get_filename: return pointer to copy of filename in the command buffer */
914 char *
915 get_filename(void)
916 {
917         static char *file = NULL;
918         static int filesz = 0;
919
920         int n;
921
922         if (*ibufp != '\n') {
923                 SKIP_BLANKS();
924                 if (*ibufp == '\n') {
925                         sprintf(errmsg, "invalid filename");
926                         return NULL;
927                 } else if ((ibufp = get_extended_line(&n, 1)) == NULL)
928                         return NULL;
929                 else if (*ibufp == '!') {
930                         ibufp++;
931                         if ((n = get_shell_command()) < 0)
932                                 return NULL;
933                         if (n)
934                                 printf("%s\n", shcmd + 1);
935                         return shcmd;
936                 } else if (n > PATH_MAX - 1) {
937                         sprintf(errmsg, "filename too long");
938                         return  NULL;
939                 }
940         }
941 #ifndef BACKWARDS
942         else if (*old_filename == '\0') {
943                 sprintf(errmsg, "no current filename");
944                 return  NULL;
945         }
946 #endif
947         REALLOC(file, filesz, PATH_MAX, NULL);
948         for (n = 0; *ibufp != '\n';)
949                 file[n++] = *ibufp++;
950         file[n] = '\0';
951         return is_legal_filename(file) ? file : NULL;
952 }
953
954
955 /* get_shell_command: read a shell command from stdin; return substitution
956    status */
957 int
958 get_shell_command(void)
959 {
960         static char *buf = NULL;
961         static int n = 0;
962
963         char *s;                        /* substitution char pointer */
964         int i = 0;
965         int j = 0;
966
967         if (red) {
968                 sprintf(errmsg, "shell access restricted");
969                 return ERR;
970         } else if ((s = ibufp = get_extended_line(&j, 1)) == NULL)
971                 return ERR;
972         REALLOC(buf, n, j + 1, ERR);
973         buf[i++] = '!';                 /* prefix command w/ bang */
974         while (*ibufp != '\n')
975                 switch (*ibufp) {
976                 default:
977                         REALLOC(buf, n, i + 2, ERR);
978                         buf[i++] = *ibufp;
979                         if (*ibufp++ == '\\')
980                                 buf[i++] = *ibufp++;
981                         break;
982                 case '!':
983                         if (s != ibufp) {
984                                 REALLOC(buf, n, i + 1, ERR);
985                                 buf[i++] = *ibufp++;
986                         }
987 #ifdef BACKWARDS
988                         else if (shcmd == NULL || *(shcmd + 1) == '\0')
989 #else
990                         else if (shcmd == NULL)
991 #endif
992                         {
993                                 sprintf(errmsg, "no previous command");
994                                 return ERR;
995                         } else {
996                                 REALLOC(buf, n, i + shcmdi, ERR);
997                                 for (s = shcmd + 1; s < shcmd + shcmdi;)
998                                         buf[i++] = *s++;
999                                 s = ibufp++;
1000                         }
1001                         break;
1002                 case '%':
1003                         if (*old_filename  == '\0') {
1004                                 sprintf(errmsg, "no current filename");
1005                                 return ERR;
1006                         }
1007                         j = strlen(s = strip_escapes(old_filename));
1008                         REALLOC(buf, n, i + j, ERR);
1009                         while (j--)
1010                                 buf[i++] = *s++;
1011                         s = ibufp++;
1012                         break;
1013                 }
1014         REALLOC(shcmd, shcmdsz, i + 1, ERR);
1015         memcpy(shcmd, buf, i);
1016         shcmd[shcmdi = i] = '\0';
1017         return *s == '!' || *s == '%';
1018 }
1019
1020
1021 /* append_lines: insert text from stdin to after line n; stop when either a
1022    single period is read or EOF; return status */
1023 int
1024 append_lines(long n)
1025 {
1026         int l;
1027         char *lp = ibuf;
1028         char *eot;
1029         undo_t *up = NULL;
1030
1031         for (current_addr = n;;) {
1032                 if (!isglobal) {
1033                         if ((l = get_tty_line()) < 0)
1034                                 return ERR;
1035                         else if (l == 0 || ibuf[l - 1] != '\n') {
1036                                 clearerr(stdin);
1037                                 return  l ? EOF : 0;
1038                         }
1039                         lp = ibuf;
1040                 } else if (*(lp = ibufp) == '\0')
1041                         return 0;
1042                 else {
1043                         while (*ibufp++ != '\n')
1044                                 ;
1045                         l = ibufp - lp;
1046                 }
1047                 if (l == 2 && lp[0] == '.' && lp[1] == '\n') {
1048                         return 0;
1049                 }
1050                 eot = lp + l;
1051                 SPL1();
1052                 do {
1053                         if ((lp = put_sbuf_line(lp)) == NULL) {
1054                                 SPL0();
1055                                 return ERR;
1056                         } else if (up)
1057                                 up->t = get_addressed_line_node(current_addr);
1058                         else if ((up = push_undo_stack(UADD, current_addr,
1059                             current_addr)) == NULL) {
1060                                 SPL0();
1061                                 return ERR;
1062                         }
1063                 } while (lp != eot);
1064                 modified = 1;
1065                 SPL0();
1066         }
1067         /* NOTREACHED */
1068 }
1069
1070
1071 /* join_lines: replace a range of lines with the joined text of those lines */
1072 int
1073 join_lines(long from, long to)
1074 {
1075         static char *buf = NULL;
1076         static int n;
1077
1078         char *s;
1079         int size = 0;
1080         line_t *bp, *ep;
1081
1082         ep = get_addressed_line_node(INC_MOD(to, addr_last));
1083         bp = get_addressed_line_node(from);
1084         for (; bp != ep; bp = bp->q_forw) {
1085                 if ((s = get_sbuf_line(bp)) == NULL)
1086                         return ERR;
1087                 REALLOC(buf, n, size + bp->len, ERR);
1088                 memcpy(buf + size, s, bp->len);
1089                 size += bp->len;
1090         }
1091         REALLOC(buf, n, size + 2, ERR);
1092         memcpy(buf + size, "\n", 2);
1093         if (delete_lines(from, to) < 0)
1094                 return ERR;
1095         current_addr = from - 1;
1096         SPL1();
1097         if (put_sbuf_line(buf) == NULL ||
1098             push_undo_stack(UADD, current_addr, current_addr) == NULL) {
1099                 SPL0();
1100                 return ERR;
1101         }
1102         modified = 1;
1103         SPL0();
1104         return 0;
1105 }
1106
1107
1108 /* move_lines: move a range of lines */
1109 int
1110 move_lines(long addr)
1111 {
1112         line_t *b1, *a1, *b2, *a2;
1113         long n = INC_MOD(second_addr, addr_last);
1114         long p = first_addr - 1;
1115         int done = (addr == first_addr - 1 || addr == second_addr);
1116
1117         SPL1();
1118         if (done) {
1119                 a2 = get_addressed_line_node(n);
1120                 b2 = get_addressed_line_node(p);
1121                 current_addr = second_addr;
1122         } else if (push_undo_stack(UMOV, p, n) == NULL ||
1123             push_undo_stack(UMOV, addr, INC_MOD(addr, addr_last)) == NULL) {
1124                 SPL0();
1125                 return ERR;
1126         } else {
1127                 a1 = get_addressed_line_node(n);
1128                 if (addr < first_addr) {
1129                         b1 = get_addressed_line_node(p);
1130                         b2 = get_addressed_line_node(addr);
1131                                         /* this get_addressed_line_node last! */
1132                 } else {
1133                         b2 = get_addressed_line_node(addr);
1134                         b1 = get_addressed_line_node(p);
1135                                         /* this get_addressed_line_node last! */
1136                 }
1137                 a2 = b2->q_forw;
1138                 REQUE(b2, b1->q_forw);
1139                 REQUE(a1->q_back, a2);
1140                 REQUE(b1, a1);
1141                 current_addr = addr + ((addr < first_addr) ?
1142                     second_addr - first_addr + 1 : 0);
1143         }
1144         if (isglobal)
1145                 unset_active_nodes(b2->q_forw, a2);
1146         modified = 1;
1147         SPL0();
1148         return 0;
1149 }
1150
1151
1152 /* copy_lines: copy a range of lines; return status */
1153 int
1154 copy_lines(long addr)
1155 {
1156         line_t *lp, *np = get_addressed_line_node(first_addr);
1157         undo_t *up = NULL;
1158         long n = second_addr - first_addr + 1;
1159         long m = 0;
1160
1161         current_addr = addr;
1162         if (first_addr <= addr && addr < second_addr) {
1163                 n =  addr - first_addr + 1;
1164                 m = second_addr - addr;
1165         }
1166         for (; n > 0; n=m, m=0, np = get_addressed_line_node(current_addr + 1))
1167                 for (; n-- > 0; np = np->q_forw) {
1168                         SPL1();
1169                         if ((lp = dup_line_node(np)) == NULL) {
1170                                 SPL0();
1171                                 return ERR;
1172                         }
1173                         add_line_node(lp);
1174                         if (up)
1175                                 up->t = lp;
1176                         else if ((up = push_undo_stack(UADD, current_addr,
1177                             current_addr)) == NULL) {
1178                                 SPL0();
1179                                 return ERR;
1180                         }
1181                         modified = 1;
1182                         SPL0();
1183                 }
1184         return 0;
1185 }
1186
1187
1188 /* delete_lines: delete a range of lines */
1189 int
1190 delete_lines(long from, long to)
1191 {
1192         line_t *n, *p;
1193
1194         SPL1();
1195         if (push_undo_stack(UDEL, from, to) == NULL) {
1196                 SPL0();
1197                 return ERR;
1198         }
1199         n = get_addressed_line_node(INC_MOD(to, addr_last));
1200         p = get_addressed_line_node(from - 1);
1201                                         /* this get_addressed_line_node last! */
1202         if (isglobal)
1203                 unset_active_nodes(p->q_forw, n);
1204         REQUE(p, n);
1205         addr_last -= to - from + 1;
1206         current_addr = from - 1;
1207         modified = 1;
1208         SPL0();
1209         return 0;
1210 }
1211
1212
1213 /* display_lines: print a range of lines to stdout */
1214 int
1215 display_lines(long from, long to, int gflag)
1216 {
1217         line_t *bp;
1218         line_t *ep;
1219         char *s;
1220
1221         if (!from) {
1222                 sprintf(errmsg, "invalid address");
1223                 return ERR;
1224         }
1225         ep = get_addressed_line_node(INC_MOD(to, addr_last));
1226         bp = get_addressed_line_node(from);
1227         for (; bp != ep; bp = bp->q_forw) {
1228                 if ((s = get_sbuf_line(bp)) == NULL)
1229                         return ERR;
1230                 if (put_tty_line(s, bp->len, current_addr = from++, gflag) < 0)
1231                         return ERR;
1232         }
1233         return 0;
1234 }
1235
1236
1237 #define MAXMARK 26                      /* max number of marks */
1238
1239 line_t  *mark[MAXMARK];                 /* line markers */
1240 int markno;                             /* line marker count */
1241
1242 /* mark_line_node: set a line node mark */
1243 int
1244 mark_line_node(line_t *lp, int n)
1245 {
1246         if (!islower((unsigned char)n)) {
1247                 sprintf(errmsg, "invalid mark character");
1248                 return ERR;
1249         } else if (mark[n - 'a'] == NULL)
1250                 markno++;
1251         mark[n - 'a'] = lp;
1252         return 0;
1253 }
1254
1255
1256 /* get_marked_node_addr: return address of a marked line */
1257 long
1258 get_marked_node_addr(int n)
1259 {
1260         if (!islower((unsigned char)n)) {
1261                 sprintf(errmsg, "invalid mark character");
1262                 return ERR;
1263         }
1264         return get_line_node_addr(mark[n - 'a']);
1265 }
1266
1267
1268 /* unmark_line_node: clear line node mark */
1269 void
1270 unmark_line_node(line_t *lp)
1271 {
1272         int i;
1273
1274         for (i = 0; markno && i < MAXMARK; i++)
1275                 if (mark[i] == lp) {
1276                         mark[i] = NULL;
1277                         markno--;
1278                 }
1279 }
1280
1281
1282 /* dup_line_node: return a pointer to a copy of a line node */
1283 line_t *
1284 dup_line_node(line_t *lp)
1285 {
1286         line_t *np;
1287
1288         if ((np = (line_t *) malloc(sizeof(line_t))) == NULL) {
1289                 fprintf(stderr, "%s\n", strerror(errno));
1290                 sprintf(errmsg, "out of memory");
1291                 return NULL;
1292         }
1293         np->seek = lp->seek;
1294         np->len = lp->len;
1295         return np;
1296 }
1297
1298
1299 /* has_trailing_escape:  return the parity of escapes preceding a character
1300    in a string */
1301 int
1302 has_trailing_escape(char *s, char *t)
1303 {
1304     return (s == t || *(t - 1) != '\\') ? 0 : !has_trailing_escape(s, t - 1);
1305 }
1306
1307
1308 /* strip_escapes: return copy of escaped string of at most length PATH_MAX */
1309 char *
1310 strip_escapes(const char *s)
1311 {
1312         static char *file = NULL;
1313         static int filesz = 0;
1314
1315         int i = 0;
1316
1317         REALLOC(file, filesz, PATH_MAX, NULL);
1318         while (i < filesz - 1   /* Worry about a possible trailing escape */
1319                && (file[i++] = (*s == '\\') ? *++s : *s))
1320                 s++;
1321         return file;
1322 }
1323
1324
1325 void
1326 signal_hup(int signo)
1327 {
1328         if (mutex)
1329                 sigflags |= (1 << (signo - 1));
1330         else
1331                 handle_hup(signo);
1332 }
1333
1334
1335 void
1336 signal_int(int signo)
1337 {
1338         if (mutex)
1339                 sigflags |= (1 << (signo - 1));
1340         else
1341                 handle_int(signo);
1342 }
1343
1344
1345 void
1346 handle_hup(int signo)
1347 {
1348         char *hup = NULL;               /* hup filename */
1349         char *s;
1350         int n;
1351
1352         if (!sigactive)
1353                 quit(1);
1354         sigflags &= ~(1 << (signo - 1));
1355         if (addr_last && write_file("ed.hup", "w", 1, addr_last) < 0 &&
1356             (s = getenv("HOME")) != NULL &&
1357             (n = strlen(s)) + 8 <= PATH_MAX &&  /* "ed.hup" + '/' */
1358             (hup = (char *) malloc(n + 10)) != NULL) {
1359                 strcpy(hup, s);
1360                 if (hup[n - 1] != '/')
1361                         hup[n] = '/', hup[n+1] = '\0';
1362                 strcat(hup, "ed.hup");
1363                 write_file(hup, "w", 1, addr_last);
1364         }
1365         quit(2);
1366 }
1367
1368
1369 void
1370 handle_int(int signo)
1371 {
1372         if (!sigactive)
1373                 quit(1);
1374         sigflags &= ~(1 << (signo - 1));
1375 #ifdef _POSIX_SOURCE
1376         siglongjmp(env, -1);
1377 #else
1378         longjmp(env, -1);
1379 #endif
1380 }
1381
1382
1383 int cols = 72;                          /* wrap column */
1384
1385 void
1386 handle_winch(int signo)
1387 {
1388         int save_errno = errno;
1389
1390         struct winsize ws;              /* window size structure */
1391
1392         sigflags &= ~(1 << (signo - 1));
1393         if (ioctl(0, TIOCGWINSZ, (char *) &ws) >= 0) {
1394                 if (ws.ws_row > 2) rows = ws.ws_row - 2;
1395                 if (ws.ws_col > 8) cols = ws.ws_col - 8;
1396         }
1397         errno = save_errno;
1398 }
1399
1400
1401 /* is_legal_filename: return a legal filename */
1402 int
1403 is_legal_filename(char *s)
1404 {
1405         if (red && (*s == '!' || !strcmp(s, "..") || strchr(s, '/'))) {
1406                 sprintf(errmsg, "shell access restricted");
1407                 return 0;
1408         }
1409         return 1;
1410 }