xref: /openbsd/usr.bin/sed/main.c (revision 4b7c5037)
1 /*	$OpenBSD: main.c,v 1.44 2023/02/08 08:18:11 tb Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992 Diomidis Spinellis.
5  * Copyright (c) 1992, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Diomidis Spinellis of Imperial College, University of London.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/ioctl.h>
38 #include <sys/stat.h>
39 
40 #include <ctype.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <limits.h>
44 #include <regex.h>
45 #include <stddef.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <libgen.h>
51 
52 #include "defs.h"
53 #include "extern.h"
54 
55 /*
56  * Linked list of units (strings and files) to be compiled
57  */
58 struct s_compunit {
59 	struct s_compunit *next;
60 	enum e_cut {CU_FILE, CU_STRING} type;
61 	char *s;			/* Pointer to string or fname */
62 };
63 
64 /*
65  * Linked list pointer to compilation units and pointer to current
66  * next pointer.
67  */
68 static struct s_compunit *script, **cu_nextp = &script;
69 
70 /*
71  * Linked list of files to be processed
72  */
73 struct s_flist {
74 	char *fname;
75 	struct s_flist *next;
76 };
77 
78 /*
79  * Linked list pointer to files and pointer to current
80  * next pointer.
81  */
82 static struct s_flist *files, **fl_nextp = &files;
83 
84 FILE *infile;			/* Current input file */
85 FILE *outfile;			/* Current output file */
86 
87 int Eflag, aflag, eflag, nflag;
88 static int rval;	/* Exit status */
89 
90 /*
91  * Current file and line number; line numbers restart across compilation
92  * units, but span across input files.  The latter is optional if editing
93  * in place.
94  */
95 const char *fname;		/* File name. */
96 const char *outfname;		/* Output file name */
97 static char oldfname[PATH_MAX];	/* Old file name (for in-place editing) */
98 static char tmpfname[PATH_MAX];	/* Temporary file name (for in-place editing) */
99 char *inplace;			/* Inplace edit file extension */
100 u_long linenum;
101 
102 static void add_compunit(enum e_cut, char *);
103 static void add_file(char *);
104 static int next_files_have_lines(void);
105 
106 int termwidth;
107 
108 int pledge_wpath, pledge_rpath;
109 
110 int
main(int argc,char * argv[])111 main(int argc, char *argv[])
112 {
113 	struct winsize win;
114 	int c, fflag;
115 	char *p;
116 
117 	fflag = 0;
118 	inplace = NULL;
119 	while ((c = getopt(argc, argv, "Eae:f:i::nru")) != -1)
120 		switch (c) {
121 		case 'E':
122 		case 'r':
123 			Eflag = 1;
124 			break;
125 		case 'a':
126 			aflag = 1;
127 			break;
128 		case 'e':
129 			eflag = 1;
130 			add_compunit(CU_STRING, optarg);
131 			break;
132 		case 'f':
133 			fflag = 1;
134 			add_compunit(CU_FILE, optarg);
135 			break;
136 		case 'i':
137 			inplace = optarg ? optarg : "";
138 			break;
139 		case 'n':
140 			nflag = 1;
141 			break;
142 		case 'u':
143 			setvbuf(stdout, NULL, _IOLBF, 0);
144 			break;
145 		default:
146 			(void)fprintf(stderr,
147 			    "usage: sed [-aEnru] [-i[extension]] command [file ...]\n"
148 			    "       sed [-aEnru] [-e command] [-f command_file] [-i[extension]] [file ...]\n");
149 			exit(1);
150 		}
151 	argc -= optind;
152 	argv += optind;
153 
154 	termwidth = 0;
155 	if ((p = getenv("COLUMNS")) != NULL)
156 		termwidth = strtonum(p, 0, INT_MAX, NULL);
157 	if (termwidth == 0 && ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
158 	    win.ws_col > 0)
159 		termwidth = win.ws_col;
160 	if (termwidth == 0)
161 		termwidth = 80;
162 	if (termwidth <= 8)
163 		termwidth = 1;
164 	else
165 		termwidth -= 8;
166 
167 	if (inplace != NULL) {
168 		if (pledge("stdio rpath wpath cpath fattr chown", NULL) == -1)
169 			error(FATAL, "pledge: %s", strerror(errno));
170 	} else {
171 		if (pledge("stdio rpath wpath cpath", NULL) == -1)
172 			error(FATAL, "pledge: %s", strerror(errno));
173 	}
174 
175 	/* First usage case; script is the first arg */
176 	if (!eflag && !fflag && *argv) {
177 		add_compunit(CU_STRING, *argv);
178 		argv++;
179 	}
180 
181 	compile();
182 
183 	/* Continue with first and start second usage */
184 	if (*argv) {
185 		if (!pledge_wpath && inplace == NULL) {
186 			if (pledge("stdio rpath", NULL) == -1)
187 				error(FATAL, "pledge: %s", strerror(errno));
188 		}
189 		for (; *argv; argv++)
190 			add_file(*argv);
191 	} else {
192 		if (!pledge_wpath && !pledge_rpath) {
193 			if (pledge("stdio", NULL) == -1)
194 				error(FATAL, "pledge: %s", strerror(errno));
195 		} else if (pledge_rpath) {
196 			if (pledge("stdio rpath", NULL) == -1)
197 				error(FATAL, "pledge: %s", strerror(errno));
198 		} else if (pledge_wpath) {
199 			if (pledge("stdio wpath cpath", NULL) == -1)
200 				error(FATAL, "pledge: %s", strerror(errno));
201 		}
202 		add_file(NULL);
203 	}
204 	process();
205 	cfclose(prog, NULL);
206 	if (fclose(stdout))
207 		error(FATAL, "stdout: %s", strerror(errno));
208 	exit (rval);
209 }
210 
211 /*
212  * Like fgets, but go through the chain of compilation units chaining them
213  * together.  Empty strings and files are ignored.
214  */
215 char *
cu_fgets(char ** outbuf,size_t * outsize)216 cu_fgets(char **outbuf, size_t *outsize)
217 {
218 	static enum {ST_EOF, ST_FILE, ST_STRING} state = ST_EOF;
219 	static FILE *f;		/* Current open file */
220 	static char *s;		/* Current pointer inside string */
221 	static char string_ident[30];
222 	size_t len;
223 	char *p;
224 
225 	if (*outbuf == NULL)
226 		*outsize = 0;
227 
228 again:
229 	switch (state) {
230 	case ST_EOF:
231 		if (script == NULL)
232 			return (NULL);
233 		linenum = 0;
234 		switch (script->type) {
235 		case CU_FILE:
236 			if ((f = fopen(script->s, "r")) == NULL)
237 				error(FATAL,
238 				    "%s: %s", script->s, strerror(errno));
239 			fname = script->s;
240 			state = ST_FILE;
241 			goto again;
242 		case CU_STRING:
243 			len = snprintf(string_ident, sizeof(string_ident),
244 			    "\"%s\"", script->s);
245 			if (len >= sizeof(string_ident))
246 				strlcpy(string_ident +
247 				    sizeof(string_ident) - 6, " ...\"", 5);
248 			fname = string_ident;
249 			s = script->s;
250 			state = ST_STRING;
251 			goto again;
252 		}
253 	case ST_FILE:
254 		if (getline(outbuf, outsize, f) != -1) {
255 			p = *outbuf;
256 			linenum++;
257 			if (linenum == 1 && p[0] == '#' && p[1] == 'n')
258 				nflag = 1;
259 			return (*outbuf);
260 		}
261 		script = script->next;
262 		(void)fclose(f);
263 		state = ST_EOF;
264 		goto again;
265 	case ST_STRING:
266 		if (linenum == 0 && s[0] == '#' && s[1] == 'n')
267 			nflag = 1;
268 		p = *outbuf;
269 		len = *outsize;
270 		for (;;) {
271 			if (len <= 1) {
272 				*outbuf = xrealloc(*outbuf,
273 				    *outsize + _POSIX2_LINE_MAX);
274 				p = *outbuf + *outsize - len;
275 				len += _POSIX2_LINE_MAX;
276 				*outsize += _POSIX2_LINE_MAX;
277 			}
278 			switch (*s) {
279 			case '\0':
280 				state = ST_EOF;
281 				if (s == script->s) {
282 					script = script->next;
283 					goto again;
284 				} else {
285 					script = script->next;
286 					*p = '\0';
287 					linenum++;
288 					return (*outbuf);
289 				}
290 			case '\n':
291 				*p++ = '\n';
292 				*p = '\0';
293 				s++;
294 				linenum++;
295 				return (*outbuf);
296 			default:
297 				*p++ = *s++;
298 				len--;
299 			}
300 		}
301 	}
302 
303 	return (NULL);
304 }
305 
306 void
finish_file(void)307 finish_file(void)
308 {
309 	if (infile != NULL) {
310 		fclose(infile);
311 		if (*oldfname != '\0') {
312 			if (rename(fname, oldfname) != 0) {
313 				warning("rename()");
314 				unlink(tmpfname);
315 				exit(1);
316 			}
317 			*oldfname = '\0';
318 		}
319 		if (*tmpfname != '\0') {
320 			if (outfile != NULL && outfile != stdout)
321 				fclose(outfile);
322 			outfile = NULL;
323 			rename(tmpfname, fname);
324 			*tmpfname = '\0';
325 		}
326 		outfname = NULL;
327 	}
328 }
329 
330 /*
331  * Like fgets, but go through the list of files chaining them together.
332  * Set len to the length of the line.
333  */
334 int
mf_fgets(SPACE * sp,enum e_spflag spflag)335 mf_fgets(SPACE *sp, enum e_spflag spflag)
336 {
337 	struct stat sb;
338 	size_t len;
339 	char dirbuf[PATH_MAX];
340 	static char *p;
341 	static size_t psize;
342 	int c, fd;
343 	static int firstfile;
344 
345 	if (infile == NULL) {
346 		/* stdin? */
347 		if (files->fname == NULL) {
348 			if (inplace != NULL)
349 				error(FATAL, "-i may not be used with stdin");
350 			infile = stdin;
351 			fname = "stdin";
352 			outfile = stdout;
353 			outfname = "stdout";
354 		}
355 
356 		firstfile = 1;
357 	}
358 
359 	for (;;) {
360 		if (infile != NULL && (c = getc(infile)) != EOF) {
361 			(void)ungetc(c, infile);
362 			break;
363 		}
364 		/* If we are here then either eof or no files are open yet */
365 		if (infile == stdin) {
366 			sp->len = 0;
367 			return (0);
368 		}
369 		finish_file();
370 		if (firstfile == 0)
371 			files = files->next;
372 		else
373 			firstfile = 0;
374 		if (files == NULL) {
375 			sp->len = 0;
376 			return (0);
377 		}
378 		fname = files->fname;
379 		if (inplace != NULL) {
380 			if (lstat(fname, &sb) != 0)
381 				error(FATAL, "%s: %s", fname,
382 				    strerror(errno ? errno : EIO));
383 			if (!S_ISREG(sb.st_mode))
384 				error(FATAL, "%s: %s %s", fname,
385 				    "in-place editing only",
386 				    "works for regular files");
387 			if (*inplace != '\0') {
388 				strlcpy(oldfname, fname,
389 				    sizeof(oldfname));
390 				len = strlcat(oldfname, inplace,
391 				    sizeof(oldfname));
392 				if (len > sizeof(oldfname))
393 					error(FATAL, "%s: name too long", fname);
394 			}
395 			strlcpy(dirbuf, fname, sizeof(dirbuf));
396 			len = snprintf(tmpfname, sizeof(tmpfname),
397 			    "%s/sedXXXXXXXXXX", dirname(dirbuf));
398 			if (len >= sizeof(tmpfname))
399 				error(FATAL, "%s: name too long", fname);
400 			if ((fd = mkstemp(tmpfname)) == -1)
401 				error(FATAL, "%s: %s", fname, strerror(errno));
402 			if ((outfile = fdopen(fd, "w")) == NULL) {
403 				unlink(tmpfname);
404 				error(FATAL, "%s", fname);
405 			}
406 			fchown(fileno(outfile), sb.st_uid, sb.st_gid);
407 			fchmod(fileno(outfile), sb.st_mode & ALLPERMS);
408 			outfname = tmpfname;
409 			linenum = 0;
410 			resetstate();
411 		} else {
412 			outfile = stdout;
413 			outfname = "stdout";
414 		}
415 		if ((infile = fopen(fname, "r")) == NULL) {
416 			warning("%s", strerror(errno));
417 			rval = 1;
418 			continue;
419 		}
420 	}
421 
422 	/*
423 	 * We are here only when infile is open and we still have something
424 	 * to read from it.
425 	 *
426 	 * Use getline() so that we can handle essentially infinite input
427 	 * data.  The p and psize are static so each invocation gives
428 	 * getline() the same buffer which is expanded as needed.
429 	 */
430 	len = getline(&p, &psize, infile);
431 	if ((ssize_t)len == -1)
432 		error(FATAL, "%s: %s", fname, strerror(errno));
433 	if (len != 0 && p[len - 1] == '\n') {
434 		sp->append_newline = 1;
435 		len--;
436 	} else if (!lastline()) {
437 		sp->append_newline = 1;
438 	} else {
439 		sp->append_newline = 0;
440 	}
441 	cspace(sp, p, len, spflag);
442 
443 	linenum++;
444 
445 	return (1);
446 }
447 
448 /*
449  * Add a compilation unit to the linked list
450  */
451 static void
add_compunit(enum e_cut type,char * s)452 add_compunit(enum e_cut type, char *s)
453 {
454 	struct s_compunit *cu;
455 
456 	cu = xmalloc(sizeof(struct s_compunit));
457 	cu->type = type;
458 	cu->s = s;
459 	cu->next = NULL;
460 	*cu_nextp = cu;
461 	cu_nextp = &cu->next;
462 }
463 
464 /*
465  * Add a file to the linked list
466  */
467 static void
add_file(char * s)468 add_file(char *s)
469 {
470 	struct s_flist *fp;
471 
472 	fp = xmalloc(sizeof(struct s_flist));
473 	fp->next = NULL;
474 	*fl_nextp = fp;
475 	fp->fname = s;
476 	fl_nextp = &fp->next;
477 }
478 
479 
480 static int
next_files_have_lines(void)481 next_files_have_lines(void)
482 {
483 	struct s_flist *file;
484 	FILE *file_fd;
485 	int ch;
486 
487 	file = files;
488 	while ((file = file->next) != NULL) {
489 		if ((file_fd = fopen(file->fname, "r")) == NULL)
490 			continue;
491 
492 		if ((ch = getc(file_fd)) != EOF) {
493 			/*
494 			 * This next file has content, therefore current
495 			 * file doesn't contains the last line.
496 			 */
497 			ungetc(ch, file_fd);
498 			fclose(file_fd);
499 			return (1);
500 		}
501 		fclose(file_fd);
502 	}
503 	return (0);
504 }
505 
506 int
lastline(void)507 lastline(void)
508 {
509 	int ch;
510 
511 	if (feof(infile)) {
512 		return !(
513 		    (inplace == NULL) &&
514 		    next_files_have_lines());
515 	}
516 	if ((ch = getc(infile)) == EOF) {
517 		return !(
518 		    (inplace == NULL) &&
519 		    next_files_have_lines());
520 	}
521 	ungetc(ch, infile);
522 	return (0);
523 }
524