Remove not needed void casts.
[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 1.7 2004/11/07 20:54:51 eirikn 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 #else
126                         fprintf(stderr, "crypt unavailable\n?\n");
127 #endif
128                         break;
129
130                 default:
131                         fprintf(stderr, usage, argv[0]);
132                         exit(1);
133                 }
134         argv += optind;
135         argc -= optind;
136         if (argc && **argv == '-') {
137                 scripted = 1;
138                 if (argc > 1) {
139                         optind = 1;
140                         goto top;
141                 }
142                 argv++;
143                 argc--;
144         }
145         /* assert: reliable signals! */
146 #ifdef SIGWINCH
147         handle_winch(SIGWINCH);
148         if (isatty(0)) signal(SIGWINCH, handle_winch);
149 #endif
150         signal(SIGHUP, signal_hup);
151         signal(SIGQUIT, SIG_IGN);
152         signal(SIGINT, signal_int);
153 #ifdef _POSIX_SOURCE
154         if ((status = sigsetjmp(env, 1)))
155 #else
156         if ((status = setjmp(env)))
157 #endif
158         {
159                 fputs("\n?\n", stderr);
160                 sprintf(errmsg, "interrupt");
161         } else {
162                 init_buffers();
163                 sigactive = 1;                  /* enable signal handlers */
164                 if (argc && **argv && is_legal_filename(*argv)) {
165                         if (read_file(*argv, 0) < 0 && !isatty(0))
166                                 quit(2);
167                         else if (**argv != '!')
168                                 if (strlcpy(old_filename, *argv, sizeof(old_filename))
169                                     >= sizeof(old_filename))
170                                         quit(2);
171                 } else if (argc) {
172                         fputs("?\n", stderr);
173                         if (**argv == '\0')
174                                 sprintf(errmsg, "invalid filename");
175                         if (!isatty(0))
176                                 quit(2);
177                 }
178         }
179         for (;;) {
180                 if (status < 0 && garrulous)
181                         fprintf(stderr, "%s\n", errmsg);
182                 if (prompt) {
183                         printf("%s", prompt);
184                         fflush(stdout);
185                 }
186                 if ((n = get_tty_line()) < 0) {
187                         status = ERR;
188                         continue;
189                 } else if (n == 0) {
190                         if (modified && !scripted) {
191                                 fputs("?\n", stderr);
192                                 sprintf(errmsg, "warning: file modified");
193                                 if (!isatty(0)) {
194                                         fprintf(stderr, garrulous ?
195                                             "script, line %d: %s\n" :
196                                             "", lineno, errmsg);
197                                         quit(2);
198                                 }
199                                 clearerr(stdin);
200                                 modified = 0;
201                                 status = EMOD;
202                                 continue;
203                         } else
204                                 quit(0);
205                 } else if (ibuf[n - 1] != '\n') {
206                         /* discard line */
207                         sprintf(errmsg, "unexpected end-of-file");
208                         clearerr(stdin);
209                         status = ERR;
210                         continue;
211                 }
212                 isglobal = 0;
213                 if ((status = extract_addr_range()) >= 0 &&
214                     (status = exec_command()) >= 0)
215                         if (!status ||
216                             (status = display_lines(current_addr, current_addr,
217                                 status)) >= 0)
218                                 continue;
219                 switch (status) {
220                 case EOF:
221                         quit(0);
222                 case EMOD:
223                         modified = 0;
224                         fputs("?\n", stderr);           /* give warning */
225                         sprintf(errmsg, "warning: file modified");
226                         if (!isatty(0)) {
227                                 fprintf(stderr, garrulous ?
228                                     "script, line %d: %s\n" :
229                                     "", lineno, errmsg);
230                                 quit(2);
231                         }
232                         break;
233                 case FATAL:
234                         if (!isatty(0))
235                                 fprintf(stderr, garrulous ?
236                                     "script, line %d: %s\n" : "",
237                                     lineno, errmsg);
238                         else
239                                 fprintf(stderr, garrulous ? "%s\n" : "",
240                                     errmsg);
241                         quit(3);
242                 default:
243                         fputs("?\n", stderr);
244                         if (!isatty(0)) {
245                                 fprintf(stderr, garrulous ?
246                                     "script, line %d: %s\n" : "",
247                                     lineno, errmsg);
248                                 quit(2);
249                         }
250                         break;
251                 }
252         }
253         /*NOTREACHED*/
254 }
255
256 long first_addr, second_addr, addr_cnt;
257
258 /* extract_addr_range: get line addresses from the command buffer until an
259    illegal address is seen; return status */
260 int
261 extract_addr_range(void)
262 {
263         long addr;
264
265         addr_cnt = 0;
266         first_addr = second_addr = current_addr;
267         while ((addr = next_addr()) >= 0) {
268                 addr_cnt++;
269                 first_addr = second_addr;
270                 second_addr = addr;
271                 if (*ibufp != ',' && *ibufp != ';')
272                         break;
273                 else if (*ibufp++ == ';')
274                         current_addr = addr;
275         }
276         if ((addr_cnt = min(addr_cnt, 2)) == 1 || second_addr != addr)
277                 first_addr = second_addr;
278         return (addr == ERR) ? ERR : 0;
279 }
280
281
282 #define SKIP_BLANKS() while (isspace((unsigned char)*ibufp) && *ibufp != '\n') ibufp++
283
284 #define MUST_BE_FIRST() \
285         if (!first) { sprintf(errmsg, "invalid address"); return ERR; }
286
287 /*  next_addr: return the next line address in the command buffer */
288 long
289 next_addr(void)
290 {
291         char *hd;
292         long addr = current_addr;
293         long n;
294         int first = 1;
295         int c;
296
297         SKIP_BLANKS();
298         for (hd = ibufp;; first = 0)
299                 switch (c = *ibufp) {
300                 case '+':
301                 case '\t':
302                 case ' ':
303                 case '-':
304                 case '^':
305                         ibufp++;
306                         SKIP_BLANKS();
307                         if (isdigit((unsigned char)*ibufp)) {
308                                 STRTOL(n, ibufp);
309                                 addr += (c == '-' || c == '^') ? -n : n;
310                         } else if (!isspace((unsigned char)c))
311                                 addr += (c == '-' || c == '^') ? -1 : 1;
312                         break;
313                 case '0': case '1': case '2':
314                 case '3': case '4': case '5':
315                 case '6': case '7': case '8': case '9':
316                         MUST_BE_FIRST();
317                         STRTOL(addr, ibufp);
318                         break;
319                 case '.':
320                 case '$':
321                         MUST_BE_FIRST();
322                         ibufp++;
323                         addr = (c == '.') ? current_addr : addr_last;
324                         break;
325                 case '/':
326                 case '?':
327                         MUST_BE_FIRST();
328                         if ((addr = get_matching_node_addr(
329                             get_compiled_pattern(), c == '/')) < 0)
330                                 return ERR;
331                         else if (c == *ibufp)
332                                 ibufp++;
333                         break;
334                 case '\'':
335                         MUST_BE_FIRST();
336                         ibufp++;
337                         if ((addr = get_marked_node_addr(*ibufp++)) < 0)
338                                 return ERR;
339                         break;
340                 case '%':
341                 case ',':
342                 case ';':
343                         if (first) {
344                                 ibufp++;
345                                 addr_cnt++;
346                                 second_addr = (c == ';') ? current_addr : 1;
347                                 addr = addr_last;
348                                 break;
349                         }
350                         /* FALL THROUGH */
351                 default:
352                         if (ibufp == hd)
353                                 return EOF;
354                         else if (addr < 0 || addr_last < addr) {
355                                 sprintf(errmsg, "invalid address");
356                                 return ERR;
357                         } else
358                                 return addr;
359                 }
360         /* NOTREACHED */
361 }
362
363
364 #ifdef BACKWARDS
365 /* GET_THIRD_ADDR: get a legal address from the command buffer */
366 #define GET_THIRD_ADDR(addr) \
367 { \
368         long ol1, ol2; \
369 \
370         ol1 = first_addr, ol2 = second_addr; \
371         if (extract_addr_range() < 0) \
372                 return ERR; \
373         else if (addr_cnt == 0) { \
374                 sprintf(errmsg, "destination expected"); \
375                 return ERR; \
376         } else if (second_addr < 0 || addr_last < second_addr) { \
377                 sprintf(errmsg, "invalid address"); \
378                 return ERR; \
379         } \
380         addr = second_addr; \
381         first_addr = ol1, second_addr = ol2; \
382 }
383 #else   /* BACKWARDS */
384 /* GET_THIRD_ADDR: get a legal address from the command buffer */
385 #define GET_THIRD_ADDR(addr) \
386 { \
387         long ol1, ol2; \
388 \
389         ol1 = first_addr, ol2 = second_addr; \
390         if (extract_addr_range() < 0) \
391                 return ERR; \
392         if (second_addr < 0 || addr_last < second_addr) { \
393                 sprintf(errmsg, "invalid address"); \
394                 return ERR; \
395         } \
396         addr = second_addr; \
397         first_addr = ol1, second_addr = ol2; \
398 }
399 #endif
400
401
402 /* GET_COMMAND_SUFFIX: verify the command suffix in the command buffer */
403 #define GET_COMMAND_SUFFIX() { \
404         int done = 0; \
405         do { \
406                 switch(*ibufp) { \
407                 case 'p': \
408                         gflag |= GPR, ibufp++; \
409                         break; \
410                 case 'l': \
411                         gflag |= GLS, ibufp++; \
412                         break; \
413                 case 'n': \
414                         gflag |= GNP, ibufp++; \
415                         break; \
416                 default: \
417                         done++; \
418                 } \
419         } while (!done); \
420         if (*ibufp++ != '\n') { \
421                 sprintf(errmsg, "invalid command suffix"); \
422                 return ERR; \
423         } \
424 }
425
426
427 /* sflags */
428 #define SGG 001         /* complement previous global substitute suffix */
429 #define SGP 002         /* complement previous print suffix */
430 #define SGR 004         /* use last regex instead of last pat */
431 #define SGF 010         /* repeat last substitution */
432
433 int patlock = 0;        /* if set, pattern not freed by get_compiled_pattern() */
434
435 long rows = 22;         /* scroll length: ws_row - 2 */
436
437 /* exec_command: execute the next command in command buffer; return print
438    request, if any */
439 int
440 exec_command(void)
441 {
442         static pattern_t *pat = NULL;
443         static int sgflag = 0;
444         static long sgnum = 0;
445
446         pattern_t *tpat;
447         char *fnp;
448         int gflag = 0;
449         int sflags = 0;
450         long addr = 0;
451         int n = 0;
452         int c;
453
454         SKIP_BLANKS();
455         switch(c = *ibufp++) {
456         case 'a':
457                 GET_COMMAND_SUFFIX();
458                 if (!isglobal) clear_undo_stack();
459                 if (append_lines(second_addr) < 0)
460                         return ERR;
461                 break;
462         case 'c':
463                 if (check_addr_range(current_addr, current_addr) < 0)
464                         return ERR;
465                 GET_COMMAND_SUFFIX();
466                 if (!isglobal) clear_undo_stack();
467                 if (delete_lines(first_addr, second_addr) < 0 ||
468                     append_lines(current_addr) < 0)
469                         return ERR;
470                 break;
471         case 'd':
472                 if (check_addr_range(current_addr, current_addr) < 0)
473                         return ERR;
474                 GET_COMMAND_SUFFIX();
475                 if (!isglobal) clear_undo_stack();
476                 if (delete_lines(first_addr, second_addr) < 0)
477                         return ERR;
478                 else if ((addr = INC_MOD(current_addr, addr_last)) != 0)
479                         current_addr = addr;
480                 break;
481         case 'e':
482                 if (modified && !scripted)
483                         return EMOD;
484                 /* fall through */
485         case 'E':
486                 if (addr_cnt > 0) {
487                         sprintf(errmsg, "unexpected address");
488                         return ERR;
489                 } else if (!isspace((unsigned char)*ibufp)) {
490                         sprintf(errmsg, "unexpected command suffix");
491                         return ERR;
492                 } else if ((fnp = get_filename()) == NULL)
493                         return ERR;
494                 GET_COMMAND_SUFFIX();
495                 if (delete_lines(1, addr_last) < 0)
496                         return ERR;
497                 clear_undo_stack();
498                 if (close_sbuf() < 0)
499                         return ERR;
500                 else if (open_sbuf() < 0)
501                         return FATAL;
502                 if (*fnp && *fnp != '!') strcpy(old_filename, fnp);
503 #ifdef BACKWARDS
504                 if (*fnp == '\0' && *old_filename == '\0') {
505                         sprintf(errmsg, "no current filename");
506                         return ERR;
507                 }
508 #endif
509                 if (read_file(*fnp ? fnp : old_filename, 0) < 0)
510                         return ERR;
511                 clear_undo_stack();
512                 modified = 0;
513                 u_current_addr = u_addr_last = -1;
514                 break;
515         case 'f':
516                 if (addr_cnt > 0) {
517                         sprintf(errmsg, "unexpected address");
518                         return ERR;
519                 } else if (!isspace((unsigned char)*ibufp)) {
520                         sprintf(errmsg, "unexpected command suffix");
521                         return ERR;
522                 } else if ((fnp = get_filename()) == NULL)
523                         return ERR;
524                 else if (*fnp == '!') {
525                         sprintf(errmsg, "invalid redirection");
526                         return ERR;
527                 }
528                 GET_COMMAND_SUFFIX();
529                 if (*fnp) strcpy(old_filename, fnp);
530                 printf("%s\n", strip_escapes(old_filename));
531                 break;
532         case 'g':
533         case 'v':
534         case 'G':
535         case 'V':
536                 if (isglobal) {
537                         sprintf(errmsg, "cannot nest global commands");
538                         return ERR;
539                 } else if (check_addr_range(1, addr_last) < 0)
540                         return ERR;
541                 else if (build_active_list(c == 'g' || c == 'G') < 0)
542                         return ERR;
543                 else if ((n = (c == 'G' || c == 'V')))
544                         GET_COMMAND_SUFFIX();
545                 isglobal++;
546                 if (exec_global(n, gflag) < 0)
547                         return ERR;
548                 break;
549         case 'h':
550                 if (addr_cnt > 0) {
551                         sprintf(errmsg, "unexpected address");
552                         return ERR;
553                 }
554                 GET_COMMAND_SUFFIX();
555                 if (*errmsg) fprintf(stderr, "%s\n", errmsg);
556                 break;
557         case 'H':
558                 if (addr_cnt > 0) {
559                         sprintf(errmsg, "unexpected address");
560                         return ERR;
561                 }
562                 GET_COMMAND_SUFFIX();
563                 if ((garrulous = 1 - garrulous) && *errmsg)
564                         fprintf(stderr, "%s\n", errmsg);
565                 break;
566         case 'i':
567                 if (second_addr == 0) {
568                         sprintf(errmsg, "invalid address");
569                         return ERR;
570                 }
571                 GET_COMMAND_SUFFIX();
572                 if (!isglobal) clear_undo_stack();
573                 if (append_lines(second_addr - 1) < 0)
574                         return ERR;
575                 break;
576         case 'j':
577                 if (check_addr_range(current_addr, current_addr + 1) < 0)
578                         return ERR;
579                 GET_COMMAND_SUFFIX();
580                 if (!isglobal) clear_undo_stack();
581                 if (first_addr != second_addr &&
582                     join_lines(first_addr, second_addr) < 0)
583                         return ERR;
584                 break;
585         case 'k':
586                 c = *ibufp++;
587                 if (second_addr == 0) {
588                         sprintf(errmsg, "invalid address");
589                         return ERR;
590                 }
591                 GET_COMMAND_SUFFIX();
592                 if (mark_line_node(get_addressed_line_node(second_addr), c) < 0)
593                         return ERR;
594                 break;
595         case 'l':
596                 if (check_addr_range(current_addr, current_addr) < 0)
597                         return ERR;
598                 GET_COMMAND_SUFFIX();
599                 if (display_lines(first_addr, second_addr, gflag | GLS) < 0)
600                         return ERR;
601                 gflag = 0;
602                 break;
603         case 'm':
604                 if (check_addr_range(current_addr, current_addr) < 0)
605                         return ERR;
606                 GET_THIRD_ADDR(addr);
607                 if (first_addr <= addr && addr < second_addr) {
608                         sprintf(errmsg, "invalid destination");
609                         return ERR;
610                 }
611                 GET_COMMAND_SUFFIX();
612                 if (!isglobal) clear_undo_stack();
613                 if (move_lines(addr) < 0)
614                         return ERR;
615                 break;
616         case 'n':
617                 if (check_addr_range(current_addr, current_addr) < 0)
618                         return ERR;
619                 GET_COMMAND_SUFFIX();
620                 if (display_lines(first_addr, second_addr, gflag | GNP) < 0)
621                         return ERR;
622                 gflag = 0;
623                 break;
624         case 'p':
625                 if (check_addr_range(current_addr, current_addr) < 0)
626                         return ERR;
627                 GET_COMMAND_SUFFIX();
628                 if (display_lines(first_addr, second_addr, gflag | GPR) < 0)
629                         return ERR;
630                 gflag = 0;
631                 break;
632         case 'P':
633                 if (addr_cnt > 0) {
634                         sprintf(errmsg, "unexpected address");
635                         return ERR;
636                 }
637                 GET_COMMAND_SUFFIX();
638                 prompt = prompt ? NULL : optarg ? optarg : dps;
639                 break;
640         case 'q':
641         case 'Q':
642                 if (addr_cnt > 0) {
643                         sprintf(errmsg, "unexpected address");
644                         return ERR;
645                 }
646                 GET_COMMAND_SUFFIX();
647                 gflag =  (modified && !scripted && c == 'q') ? EMOD : EOF;
648                 break;
649         case 'r':
650                 if (!isspace((unsigned char)*ibufp)) {
651                         sprintf(errmsg, "unexpected command suffix");
652                         return ERR;
653                 } else if (addr_cnt == 0)
654                         second_addr = addr_last;
655                 if ((fnp = get_filename()) == NULL)
656                         return ERR;
657                 GET_COMMAND_SUFFIX();
658                 if (!isglobal) clear_undo_stack();
659                 if (*old_filename == '\0' && *fnp != '!')
660                         strcpy(old_filename, fnp);
661 #ifdef BACKWARDS
662                 if (*fnp == '\0' && *old_filename == '\0') {
663                         sprintf(errmsg, "no current filename");
664                         return ERR;
665                 }
666 #endif
667                 if ((addr = read_file(*fnp ? fnp : old_filename, second_addr)) < 0)
668                         return ERR;
669                 else if (addr && addr != addr_last)
670                         modified = 1;
671                 break;
672         case 's':
673                 do {
674                         switch(*ibufp) {
675                         case '\n':
676                                 sflags |=SGF;
677                                 break;
678                         case 'g':
679                                 sflags |= SGG;
680                                 ibufp++;
681                                 break;
682                         case 'p':
683                                 sflags |= SGP;
684                                 ibufp++;
685                                 break;
686                         case 'r':
687                                 sflags |= SGR;
688                                 ibufp++;
689                                 break;
690                         case '0': case '1': case '2': case '3': case '4':
691                         case '5': case '6': case '7': case '8': case '9':
692                                 STRTOL(sgnum, ibufp);
693                                 sflags |= SGF;
694                                 sgflag &= ~GSG;         /* override GSG */
695                                 break;
696                         default:
697                                 if (sflags) {
698                                         sprintf(errmsg, "invalid command suffix");
699                                         return ERR;
700                                 }
701                         }
702                 } while (sflags && *ibufp != '\n');
703                 if (sflags && !pat) {
704                         sprintf(errmsg, "no previous substitution");
705                         return ERR;
706                 } else if (sflags & SGG)
707                         sgnum = 0;              /* override numeric arg */
708                 if (*ibufp != '\n' && *(ibufp + 1) == '\n') {
709                         sprintf(errmsg, "invalid pattern delimiter");
710                         return ERR;
711                 }
712                 tpat = pat;
713                 SPL1();
714                 if ((!sflags || (sflags & SGR)) &&
715                     (tpat = get_compiled_pattern()) == NULL) {
716                         SPL0();
717                         return ERR;
718                 } else if (tpat != pat) {
719                         if (pat) {
720                                 regfree(pat);
721                                 free(pat);
722                         }
723                         pat = tpat;
724                         patlock = 1;            /* reserve pattern */
725                 }
726                 SPL0();
727                 if (!sflags && extract_subst_tail(&sgflag, &sgnum) < 0)
728                         return ERR;
729                 else if (isglobal)
730                         sgflag |= GLB;
731                 else
732                         sgflag &= ~GLB;
733                 if (sflags & SGG)
734                         sgflag ^= GSG;
735                 if (sflags & SGP)
736                         sgflag ^= GPR, sgflag &= ~(GLS | GNP);
737                 do {
738                         switch(*ibufp) {
739                         case 'p':
740                                 sgflag |= GPR, ibufp++;
741                                 break;
742                         case 'l':
743                                 sgflag |= GLS, ibufp++;
744                                 break;
745                         case 'n':
746                                 sgflag |= GNP, ibufp++;
747                                 break;
748                         default:
749                                 n++;
750                         }
751                 } while (!n);
752                 if (check_addr_range(current_addr, current_addr) < 0)
753                         return ERR;
754                 GET_COMMAND_SUFFIX();
755                 if (!isglobal) clear_undo_stack();
756                 if (search_and_replace(pat, sgflag, sgnum) < 0)
757                         return ERR;
758                 break;
759         case 't':
760                 if (check_addr_range(current_addr, current_addr) < 0)
761                         return ERR;
762                 GET_THIRD_ADDR(addr);
763                 GET_COMMAND_SUFFIX();
764                 if (!isglobal) clear_undo_stack();
765                 if (copy_lines(addr) < 0)
766                         return ERR;
767                 break;
768         case 'u':
769                 if (addr_cnt > 0) {
770                         sprintf(errmsg, "unexpected address");
771                         return ERR;
772                 }
773                 GET_COMMAND_SUFFIX();
774                 if (pop_undo_stack() < 0)
775                         return ERR;
776                 break;
777         case 'w':
778         case 'W':
779                 if ((n = *ibufp) == 'q' || n == 'Q') {
780                         gflag = EOF;
781                         ibufp++;
782                 }
783                 if (!isspace((unsigned char)*ibufp)) {
784                         sprintf(errmsg, "unexpected command suffix");
785                         return ERR;
786                 } else if ((fnp = get_filename()) == NULL)
787                         return ERR;
788                 if (addr_cnt == 0 && !addr_last)
789                         first_addr = second_addr = 0;
790                 else if (check_addr_range(1, addr_last) < 0)
791                         return ERR;
792                 GET_COMMAND_SUFFIX();
793                 if (*old_filename == '\0' && *fnp != '!')
794                         strcpy(old_filename, fnp);
795 #ifdef BACKWARDS
796                 if (*fnp == '\0' && *old_filename == '\0') {
797                         sprintf(errmsg, "no current filename");
798                         return ERR;
799                 }
800 #endif
801                 if ((addr = write_file(*fnp ? fnp : old_filename,
802                     (c == 'W') ? "a" : "w", first_addr, second_addr)) < 0)
803                         return ERR;
804                 else if (addr == addr_last)
805                         modified = 0;
806                 else if (modified && !scripted && n == 'q')
807                         gflag = EMOD;
808                 break;
809         case 'x':
810                 if (addr_cnt > 0) {
811                         sprintf(errmsg, "unexpected address");
812                         return ERR;
813                 }
814                 GET_COMMAND_SUFFIX();
815 #ifdef DES
816                 des = get_keyword();
817 #else
818                 sprintf(errmsg, "crypt unavailable");
819                 return ERR;
820 #endif
821                 break;
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 }