xref: /openbsd/usr.bin/less/main.c (revision 404b540a)
1 /*
2  * Copyright (C) 1984-2002  Mark Nudelman
3  *
4  * You may distribute under the terms of either the GNU General Public
5  * License or the Less License, as specified in the README file.
6  *
7  * For more information about less, or for information on how to
8  * contact the author, see the README file.
9  */
10 
11 
12 /*
13  * Entry point, initialization, miscellaneous routines.
14  */
15 
16 #include "less.h"
17 #if MSDOS_COMPILER==WIN32C
18 #include <windows.h>
19 #endif
20 
21 public char *	every_first_cmd = NULL;
22 public int	new_file;
23 public int	is_tty;
24 public IFILE	curr_ifile = NULL_IFILE;
25 public IFILE	old_ifile = NULL_IFILE;
26 public struct scrpos initial_scrpos;
27 public int	any_display = FALSE;
28 public POSITION	start_attnpos = NULL_POSITION;
29 public POSITION	end_attnpos = NULL_POSITION;
30 public int	wscroll;
31 public char *	progname;
32 public int	quitting;
33 public int	secure;
34 public int	ismore;
35 
36 #if LOGFILE
37 public int	logfile = -1;
38 public int	force_logfile = FALSE;
39 public char *	namelogfile = NULL;
40 #endif
41 
42 #if EDITOR
43 public char *	editor;
44 public char *	editproto;
45 #endif
46 
47 #if TAGS
48 extern char *	tags;
49 extern char *	tagoption;
50 extern int	jump_sline;
51 #endif
52 
53 #ifdef WIN32
54 static char consoleTitle[256];
55 #endif
56 
57 extern int	missing_cap;
58 extern int	know_dumb;
59 
60 extern char *	__progname;
61 
62 /*
63  * Entry point.
64  */
65 int
66 main(argc, argv)
67 	int argc;
68 	char *argv[];
69 {
70 	IFILE ifile;
71 	char *s;
72 
73 #ifdef __EMX__
74 	_response(&argc, &argv);
75 	_wildcard(&argc, &argv);
76 #endif
77 
78 	progname = *argv++;
79 	argc--;
80 
81 	secure = 0;
82 	s = lgetenv("LESSSECURE");
83 	if (s != NULL && *s != '\0')
84 		secure = 1;
85 
86 #ifdef WIN32
87 	if (getenv("HOME") == NULL)
88 	{
89 		/*
90 		 * If there is no HOME environment variable,
91 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
92 		 */
93 		char *drive = getenv("HOMEDRIVE");
94 		char *path  = getenv("HOMEPATH");
95 		if (drive != NULL && path != NULL)
96 		{
97 			size_t len = strlen(drive) + strlen(path) + 6;
98 			char *env = (char *) ecalloc(len, sizeof(char));
99 			strlcpy(env, "HOME=", len);
100 			strlcat(env, drive, len);
101 			strlcat(env, path, len);
102 			putenv(env);
103 		}
104 	}
105 	GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
106 #endif /* WIN32 */
107 
108 	/*
109 	 * Process command line arguments and LESS environment arguments.
110 	 * Command line arguments override environment arguments.
111 	 */
112 	ismore = !strcmp(__progname, "more");
113 	is_tty = isatty(1);
114 	get_term();
115 	init_cmds();
116 	init_prompt();
117 	init_charset();
118 	init_line();
119 	init_option();
120 	if (ismore) {
121 		scan_option("-E");
122 		scan_option("-G");
123 		scan_option("-L");
124 		scan_option("-m");
125 		s = lgetenv("MORE");
126 	} else
127 		s = lgetenv("LESS");
128 	if (s != NULL)
129 		scan_option(save(s));
130 
131 #define	isoptstring(s)	(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
132 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
133 	{
134 		s = *argv++;
135 		argc--;
136 		if (strcmp(s, "--") == 0)
137 			break;
138 		scan_option(s);
139 	}
140 #undef isoptstring
141 
142 	if (isoptpending())
143 	{
144 		/*
145 		 * Last command line option was a flag requiring a
146 		 * following string, but there was no following string.
147 		 */
148 		nopendopt();
149 		quit(QUIT_OK);
150 	}
151 
152 #if EDITOR
153 	editor = lgetenv("VISUAL");
154 	if (editor == NULL || *editor == '\0')
155 	{
156 		editor = lgetenv("EDITOR");
157 		if (editor == NULL || *editor == '\0')
158 			editor = EDIT_PGM;
159 	}
160 	editproto = lgetenv("LESSEDIT");
161 	if (editproto == NULL || *editproto == '\0')
162 		editproto = "%E ?lm+%lm. %f";
163 #endif
164 
165 	/*
166 	 * Call get_ifile with all the command line filenames
167 	 * to "register" them with the ifile system.
168 	 */
169 	ifile = NULL_IFILE;
170 	while (argc-- > 0)
171 	{
172 		char *filename;
173 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
174 		/*
175 		 * Because the "shell" doesn't expand filename patterns,
176 		 * treat each argument as a filename pattern rather than
177 		 * a single filename.
178 		 * Expand the pattern and iterate over the expanded list.
179 		 */
180 		struct textlist tlist;
181 		char *gfilename;
182 
183 		gfilename = lglob(*argv++);
184 		init_textlist(&tlist, gfilename);
185 		filename = NULL;
186 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
187 		{
188 			(void) get_ifile(filename, ifile);
189 			ifile = prev_ifile(NULL_IFILE);
190 		}
191 		free(gfilename);
192 #else
193 		filename = shell_quote(*argv);
194 		if (filename == NULL)
195 			filename = *argv;
196 		argv++;
197 		(void) get_ifile(filename, ifile);
198 		ifile = prev_ifile(NULL_IFILE);
199 #endif
200 	}
201 	/*
202 	 * Set up terminal, etc.
203 	 */
204 	if (!is_tty)
205 	{
206 		/*
207 		 * Output is not a tty.
208 		 * Just copy the input file(s) to output.
209 		 */
210 		SET_BINARY(1);
211 		if (nifile() == 0)
212 		{
213 			if (edit_stdin() == 0)
214 				cat_file();
215 		} else if (edit_first() == 0)
216 		{
217 			do {
218 				cat_file();
219 			} while (edit_next(1) == 0);
220 		}
221 		quit(QUIT_OK);
222 	}
223 
224 	if (missing_cap && !know_dumb && !ismore)
225 		error("WARNING: terminal is not fully functional", NULL_PARG);
226 	init_mark();
227 	open_getchr();
228 	raw_mode(1);
229 	init_signals(1);
230 
231 	/*
232 	 * Select the first file to examine.
233 	 */
234 #if TAGS
235 	if (tagoption != NULL || strcmp(tags, "-") == 0)
236 	{
237 		/*
238 		 * A -t option was given.
239 		 * Verify that no filenames were also given.
240 		 * Edit the file selected by the "tags" search,
241 		 * and search for the proper line in the file.
242 		 */
243 		if (nifile() > 0)
244 		{
245 			error("No filenames allowed with -t option", NULL_PARG);
246 			quit(QUIT_ERROR);
247 		}
248 		findtag(tagoption);
249 		if (edit_tagfile())  /* Edit file which contains the tag */
250 			quit(QUIT_ERROR);
251 		/*
252 		 * Search for the line which contains the tag.
253 		 * Set up initial_scrpos so we display that line.
254 		 */
255 		initial_scrpos.pos = tagsearch();
256 		if (initial_scrpos.pos == NULL_POSITION)
257 			quit(QUIT_ERROR);
258 		initial_scrpos.ln = jump_sline;
259 	} else
260 #endif
261 	if (nifile() == 0)
262 	{
263 		if (edit_stdin())  /* Edit standard input */
264 			quit(QUIT_ERROR);
265 	} else
266 	{
267 		if (edit_first())  /* Edit first valid file in cmd line */
268 			quit(QUIT_ERROR);
269 	}
270 
271 	init();
272 	commands();
273 	quit(QUIT_OK);
274 	/*NOTREACHED*/
275 	return (0);
276 }
277 
278 /*
279  * Copy a string to a "safe" place
280  * (that is, to a buffer allocated by calloc).
281  */
282 	public char *
283 save(s)
284 	char *s;
285 {
286 	register char *p;
287 	size_t len;
288 
289 	len = strlen(s)+1, sizeof(char);
290 	p = (char *) ecalloc(len, sizeof(char));
291 	strlcpy(p, s, len);
292 	return (p);
293 }
294 
295 /*
296  * Allocate memory.
297  * Like calloc(), but never returns an error (NULL).
298  */
299 	public VOID_POINTER
300 ecalloc(count, size)
301 	int count;
302 	unsigned int size;
303 {
304 	register VOID_POINTER p;
305 
306 	p = (VOID_POINTER) calloc(count, size);
307 	if (p != NULL)
308 		return (p);
309 	error("Cannot allocate memory", NULL_PARG);
310 	quit(QUIT_ERROR);
311 	/*NOTREACHED*/
312 	return (NULL);
313 }
314 
315 /*
316  * Skip leading spaces in a string.
317  */
318 	public char *
319 skipsp(s)
320 	register char *s;
321 {
322 	while (*s == ' ' || *s == '\t')
323 		s++;
324 	return (s);
325 }
326 
327 /*
328  * See how many characters of two strings are identical.
329  * If uppercase is true, the first string must begin with an uppercase
330  * character; the remainder of the first string may be either case.
331  */
332 	public int
333 sprefix(ps, s, uppercase)
334 	char *ps;
335 	char *s;
336 	int uppercase;
337 {
338 	register int c;
339 	register int sc;
340 	register int len = 0;
341 
342 	for ( ;  *s != '\0';  s++, ps++)
343 	{
344 		c = *ps;
345 		if (uppercase)
346 		{
347 			if (len == 0 && SIMPLE_IS_LOWER(c))
348 				return (-1);
349 			if (SIMPLE_IS_UPPER(c))
350 				c = SIMPLE_TO_LOWER(c);
351 		}
352 		sc = *s;
353 		if (len > 0 && SIMPLE_IS_UPPER(sc))
354 			sc = SIMPLE_TO_LOWER(sc);
355 		if (c != sc)
356 			break;
357 		len++;
358 	}
359 	return (len);
360 }
361 
362 /*
363  * Exit the program.
364  */
365 	public void
366 quit(status)
367 	int status;
368 {
369 	static int save_status;
370 
371 	/*
372 	 * Put cursor at bottom left corner, clear the line,
373 	 * reset the terminal modes, and exit.
374 	 */
375 	if (status < 0)
376 		status = save_status;
377 	else
378 		save_status = status;
379 	quitting = 1;
380 	edit((char*)NULL);
381 	if (any_display && is_tty)
382 		clear_bot();
383 	deinit();
384 	flush();
385 	raw_mode(0);
386 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
387 	/*
388 	 * If we don't close 2, we get some garbage from
389 	 * 2's buffer when it flushes automatically.
390 	 * I cannot track this one down  RB
391 	 * The same bug shows up if we use ^C^C to abort.
392 	 */
393 	close(2);
394 #endif
395 #if WIN32
396 	SetConsoleTitle(consoleTitle);
397 #endif
398 	close_getchr();
399 	exit(status);
400 }
401