xref: /freebsd/contrib/less/main.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2012  Mark Nudelman
4  *
5  * You may distribute under the terms of either the GNU General Public
6  * License or the Less License, as specified in the README file.
7  *
8  * For more information, 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	dohelp;
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	less_is_more;
58 extern int	missing_cap;
59 extern int	know_dumb;
60 extern int	quit_if_one_screen;
61 extern int	no_init;
62 extern int	pr_type;
63 
64 
65 /*
66  * Entry point.
67  */
68 int
69 main(argc, argv)
70 	int argc;
71 	char *argv[];
72 {
73 	IFILE ifile;
74 	char *s;
75 	extern char *__progname;
76 
77 #ifdef __EMX__
78 	_response(&argc, &argv);
79 	_wildcard(&argc, &argv);
80 #endif
81 
82 	progname = *argv++;
83 	argc--;
84 
85 	secure = 0;
86 	s = lgetenv("LESSSECURE");
87 	if (s != NULL && *s != '\0')
88 		secure = 1;
89 
90 #ifdef WIN32
91 	if (getenv("HOME") == NULL)
92 	{
93 		/*
94 		 * If there is no HOME environment variable,
95 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
96 		 */
97 		char *drive = getenv("HOMEDRIVE");
98 		char *path  = getenv("HOMEPATH");
99 		if (drive != NULL && path != NULL)
100 		{
101 			char *env = (char *) ecalloc(strlen(drive) +
102 					strlen(path) + 6, sizeof(char));
103 			strcpy(env, "HOME=");
104 			strcat(env, drive);
105 			strcat(env, path);
106 			putenv(env);
107 		}
108 	}
109 	GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
110 #endif /* WIN32 */
111 
112 	/*
113 	 * Process command line arguments and LESS environment arguments.
114 	 * Command line arguments override environment arguments.
115 	 */
116 	is_tty = isatty(1);
117 	get_term();
118 	init_cmds();
119 	init_charset();
120 	init_line();
121 	init_cmdhist();
122 	init_option();
123 	init_search();
124 
125 	/*
126 	 * If the name of the executable program is "more",
127 	 * act like LESS_IS_MORE is set.
128 	 */
129 	for (s = progname + strlen(progname);  s > progname;  s--)
130 	{
131 		if (s[-1] == PATHNAME_SEP[0])
132 			break;
133 	}
134 	if (strcmp(s, "more") == 0)
135 		less_is_more = 1;
136 
137 	init_prompt();
138 
139 	if (less_is_more)
140 		scan_option("-fG");
141 
142 	s = lgetenv(less_is_more ? "MORE" : "LESS");
143 	if (s != NULL)
144 		scan_option(save(s));
145 
146 #define	isoptstring(s)	less_is_more   ? (((s)[0] == '-') && (s)[1] != '\0') : \
147 			(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
148 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
149 	{
150 		s = *argv++;
151 		argc--;
152 		if (strcmp(s, "--") == 0)
153 			break;
154 		scan_option(s);
155 	}
156 #undef isoptstring
157 
158 	if (isoptpending())
159 	{
160 		/*
161 		 * Last command line option was a flag requiring a
162 		 * following string, but there was no following string.
163 		 */
164 		nopendopt();
165 		quit(QUIT_OK);
166 	}
167 
168 	if (less_is_more)
169 		no_init = TRUE;
170 	if (less_is_more && get_quit_at_eof())
171 		quit_if_one_screen = TRUE;
172 
173 #if EDITOR
174 	editor = lgetenv("VISUAL");
175 	if (editor == NULL || *editor == '\0')
176 	{
177 		editor = lgetenv("EDITOR");
178 		if (editor == NULL || *editor == '\0')
179 			editor = EDIT_PGM;
180 	}
181 	editproto = lgetenv("LESSEDIT");
182 	if (editproto == NULL || *editproto == '\0')
183 		editproto = "%E ?lm+%lm. %f";
184 #endif
185 
186 	/*
187 	 * Call get_ifile with all the command line filenames
188 	 * to "register" them with the ifile system.
189 	 */
190 	ifile = NULL_IFILE;
191 	if (dohelp)
192 		ifile = get_ifile(FAKE_HELPFILE, ifile);
193 	while (argc-- > 0)
194 	{
195 		char *filename;
196 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
197 		/*
198 		 * Because the "shell" doesn't expand filename patterns,
199 		 * treat each argument as a filename pattern rather than
200 		 * a single filename.
201 		 * Expand the pattern and iterate over the expanded list.
202 		 */
203 		struct textlist tlist;
204 		char *gfilename;
205 
206 		gfilename = lglob(*argv++);
207 		init_textlist(&tlist, gfilename);
208 		filename = NULL;
209 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
210 		{
211 			(void) get_ifile(filename, ifile);
212 			ifile = prev_ifile(NULL_IFILE);
213 		}
214 		free(gfilename);
215 #else
216 		filename = shell_quote(*argv);
217 		if (filename == NULL)
218 			filename = *argv;
219 		argv++;
220 		(void) get_ifile(filename, ifile);
221 		ifile = prev_ifile(NULL_IFILE);
222 		free(filename);
223 #endif
224 	}
225 	/*
226 	 * Set up terminal, etc.
227 	 */
228 	if (!is_tty)
229 	{
230 		/*
231 		 * Output is not a tty.
232 		 * Just copy the input file(s) to output.
233 		 */
234 		SET_BINARY(1);
235 		if (nifile() == 0)
236 		{
237 			if (edit_stdin() == 0)
238 				cat_file();
239 		} else if (edit_first() == 0)
240 		{
241 			do {
242 				cat_file();
243 			} while (edit_next(1) == 0);
244 		}
245 		quit(QUIT_OK);
246 	}
247 
248 	if (missing_cap && !know_dumb && !less_is_more)
249 		error("WARNING: terminal is not fully functional", NULL_PARG);
250 	init_mark();
251 	open_getchr();
252 	raw_mode(1);
253 	init_signals(1);
254 
255 	/*
256 	 * Select the first file to examine.
257 	 */
258 #if TAGS
259 	if (tagoption != NULL || strcmp(tags, "-") == 0)
260 	{
261 		/*
262 		 * A -t option was given.
263 		 * Verify that no filenames were also given.
264 		 * Edit the file selected by the "tags" search,
265 		 * and search for the proper line in the file.
266 		 */
267 		if (nifile() > 0)
268 		{
269 			error("No filenames allowed with -t option", NULL_PARG);
270 			quit(QUIT_ERROR);
271 		}
272 		findtag(tagoption);
273 		if (edit_tagfile())  /* Edit file which contains the tag */
274 			quit(QUIT_ERROR);
275 		/*
276 		 * Search for the line which contains the tag.
277 		 * Set up initial_scrpos so we display that line.
278 		 */
279 		initial_scrpos.pos = tagsearch();
280 		if (initial_scrpos.pos == NULL_POSITION)
281 			quit(QUIT_ERROR);
282 		initial_scrpos.ln = jump_sline;
283 	} else
284 #endif
285 	if (nifile() == 0)
286 	{
287 		if (edit_stdin())  /* Edit standard input */
288 			quit(QUIT_ERROR);
289 	} else
290 	{
291 		if (edit_first())  /* Edit first valid file in cmd line */
292 			quit(QUIT_ERROR);
293 	}
294 
295 	init();
296 	commands();
297 	quit(QUIT_OK);
298 	/*NOTREACHED*/
299 	return (0);
300 }
301 
302 /*
303  * Copy a string to a "safe" place
304  * (that is, to a buffer allocated by calloc).
305  */
306 	public char *
307 save(s)
308 	char *s;
309 {
310 	register char *p;
311 
312 	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
313 	strcpy(p, s);
314 	return (p);
315 }
316 
317 /*
318  * Allocate memory.
319  * Like calloc(), but never returns an error (NULL).
320  */
321 	public VOID_POINTER
322 ecalloc(count, size)
323 	int count;
324 	unsigned int size;
325 {
326 	register VOID_POINTER p;
327 
328 	p = (VOID_POINTER) calloc(count, size);
329 	if (p != NULL)
330 		return (p);
331 	error("Cannot allocate memory", NULL_PARG);
332 	quit(QUIT_ERROR);
333 	/*NOTREACHED*/
334 	return (NULL);
335 }
336 
337 /*
338  * Skip leading spaces in a string.
339  */
340 	public char *
341 skipsp(s)
342 	register char *s;
343 {
344 	while (*s == ' ' || *s == '\t')
345 		s++;
346 	return (s);
347 }
348 
349 /*
350  * See how many characters of two strings are identical.
351  * If uppercase is true, the first string must begin with an uppercase
352  * character; the remainder of the first string may be either case.
353  */
354 	public int
355 sprefix(ps, s, uppercase)
356 	char *ps;
357 	char *s;
358 	int uppercase;
359 {
360 	register int c;
361 	register int sc;
362 	register int len = 0;
363 
364 	for ( ;  *s != '\0';  s++, ps++)
365 	{
366 		c = *ps;
367 		if (uppercase)
368 		{
369 			if (len == 0 && ASCII_IS_LOWER(c))
370 				return (-1);
371 			if (ASCII_IS_UPPER(c))
372 				c = ASCII_TO_LOWER(c);
373 		}
374 		sc = *s;
375 		if (len > 0 && ASCII_IS_UPPER(sc))
376 			sc = ASCII_TO_LOWER(sc);
377 		if (c != sc)
378 			break;
379 		len++;
380 	}
381 	return (len);
382 }
383 
384 /*
385  * Exit the program.
386  */
387 	public void
388 quit(status)
389 	int status;
390 {
391 	static int save_status;
392 
393 	/*
394 	 * Put cursor at bottom left corner, clear the line,
395 	 * reset the terminal modes, and exit.
396 	 */
397 	if (status < 0)
398 		status = save_status;
399 	else
400 		save_status = status;
401 	quitting = 1;
402 	edit((char*)NULL);
403 	save_cmdhist();
404 	if (any_display && is_tty)
405 		clear_bot();
406 	deinit();
407 	flush();
408 	raw_mode(0);
409 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
410 	/*
411 	 * If we don't close 2, we get some garbage from
412 	 * 2's buffer when it flushes automatically.
413 	 * I cannot track this one down  RB
414 	 * The same bug shows up if we use ^C^C to abort.
415 	 */
416 	close(2);
417 #endif
418 #ifdef WIN32
419 	SetConsoleTitle(consoleTitle);
420 #endif
421 	close_getchr();
422 	exit(status);
423 }
424