xref: /freebsd/contrib/less/main.c (revision 3157ba21)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2009  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 about less, or for information on how to
9  * contact the author, see the README file.
10  */
11 
12 
13 /*
14  * Entry point, initialization, miscellaneous routines.
15  */
16 
17 #include "less.h"
18 #if MSDOS_COMPILER==WIN32C
19 #include <windows.h>
20 #endif
21 
22 public char *	every_first_cmd = NULL;
23 public int	new_file;
24 public int	is_tty;
25 public IFILE	curr_ifile = NULL_IFILE;
26 public IFILE	old_ifile = NULL_IFILE;
27 public struct scrpos initial_scrpos;
28 public int	any_display = FALSE;
29 public POSITION	start_attnpos = NULL_POSITION;
30 public POSITION	end_attnpos = NULL_POSITION;
31 public int	wscroll;
32 public char *	progname;
33 public int	quitting;
34 public int	secure;
35 public int	dohelp;
36 public int	less_is_more;
37 
38 #if LOGFILE
39 public int	logfile = -1;
40 public int	force_logfile = FALSE;
41 public char *	namelogfile = NULL;
42 #endif
43 
44 #if EDITOR
45 public char *	editor;
46 public char *	editproto;
47 #endif
48 
49 #if TAGS
50 extern char *	tags;
51 extern char *	tagoption;
52 extern int	jump_sline;
53 #endif
54 
55 #ifdef WIN32
56 static char consoleTitle[256];
57 #endif
58 
59 extern int	missing_cap;
60 extern int	know_dumb;
61 extern int	quit_if_one_screen;
62 extern int	no_init;
63 extern int	pr_type;
64 
65 
66 /*
67  * Entry point.
68  */
69 int
70 main(argc, argv)
71 	int argc;
72 	char *argv[];
73 {
74 	IFILE ifile;
75 	char *s;
76 	extern char *__progname;
77 
78 #ifdef __EMX__
79 	_response(&argc, &argv);
80 	_wildcard(&argc, &argv);
81 #endif
82 
83 	progname = *argv++;
84 	argc--;
85 
86 	secure = 0;
87 	s = lgetenv("LESSSECURE");
88 	if (s != NULL && *s != '\0')
89 		secure = 1;
90 
91 #ifdef WIN32
92 	if (getenv("HOME") == NULL)
93 	{
94 		/*
95 		 * If there is no HOME environment variable,
96 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
97 		 */
98 		char *drive = getenv("HOMEDRIVE");
99 		char *path  = getenv("HOMEPATH");
100 		if (drive != NULL && path != NULL)
101 		{
102 			char *env = (char *) ecalloc(strlen(drive) +
103 					strlen(path) + 6, sizeof(char));
104 			strcpy(env, "HOME=");
105 			strcat(env, drive);
106 			strcat(env, path);
107 			putenv(env);
108 		}
109 	}
110 	GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
111 #endif /* WIN32 */
112 
113 	/*
114 	 * Process command line arguments and LESS environment arguments.
115 	 * Command line arguments override environment arguments.
116 	 */
117 	is_tty = isatty(1);
118 	get_term();
119 	init_cmds();
120 	init_charset();
121 	init_line();
122 	init_cmdhist();
123 	init_option();
124 	init_search();
125 
126 	/*
127 	 * If the name of the executable program is "more",
128 	 * act like LESS_IS_MORE is set.
129 	 */
130 	for (s = progname + strlen(progname);  s > progname;  s--)
131 	{
132 		if (s[-1] == PATHNAME_SEP[0])
133 			break;
134 	}
135 	if (strcmp(s, "more") == 0)
136 		less_is_more = 1;
137 
138 	init_prompt();
139 
140 	if (less_is_more)
141 		scan_option("-fG");
142 
143 	s = lgetenv(less_is_more ? "MORE" : "LESS");
144 	if (s != NULL)
145 		scan_option(save(s));
146 
147 #define	isoptstring(s)	less_is_more   ? (((s)[0] == '-') && (s)[1] != '\0') : \
148 			(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
149 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
150 	{
151 		s = *argv++;
152 		argc--;
153 		if (strcmp(s, "--") == 0)
154 			break;
155 		scan_option(s);
156 	}
157 #undef isoptstring
158 
159 	if (isoptpending())
160 	{
161 		/*
162 		 * Last command line option was a flag requiring a
163 		 * following string, but there was no following string.
164 		 */
165 		nopendopt();
166 		quit(QUIT_OK);
167 	}
168 
169 	if (less_is_more)
170 		no_init = TRUE;
171 	if (less_is_more && get_quit_at_eof())
172 		quit_if_one_screen = TRUE;
173 
174 #if EDITOR
175 	editor = lgetenv("VISUAL");
176 	if (editor == NULL || *editor == '\0')
177 	{
178 		editor = lgetenv("EDITOR");
179 		if (editor == NULL || *editor == '\0')
180 			editor = EDIT_PGM;
181 	}
182 	editproto = lgetenv("LESSEDIT");
183 	if (editproto == NULL || *editproto == '\0')
184 		editproto = "%E ?lm+%lm. %f";
185 #endif
186 
187 	/*
188 	 * Call get_ifile with all the command line filenames
189 	 * to "register" them with the ifile system.
190 	 */
191 	ifile = NULL_IFILE;
192 	if (dohelp)
193 		ifile = get_ifile(FAKE_HELPFILE, ifile);
194 	while (argc-- > 0)
195 	{
196 		char *filename;
197 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
198 		/*
199 		 * Because the "shell" doesn't expand filename patterns,
200 		 * treat each argument as a filename pattern rather than
201 		 * a single filename.
202 		 * Expand the pattern and iterate over the expanded list.
203 		 */
204 		struct textlist tlist;
205 		char *gfilename;
206 
207 		gfilename = lglob(*argv++);
208 		init_textlist(&tlist, gfilename);
209 		filename = NULL;
210 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
211 		{
212 			(void) get_ifile(filename, ifile);
213 			ifile = prev_ifile(NULL_IFILE);
214 		}
215 		free(gfilename);
216 #else
217 		filename = shell_quote(*argv);
218 		if (filename == NULL)
219 			filename = *argv;
220 		argv++;
221 		(void) get_ifile(filename, ifile);
222 		ifile = prev_ifile(NULL_IFILE);
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 #if WIN32
419 	SetConsoleTitle(consoleTitle);
420 #endif
421 	close_getchr();
422 	exit(status);
423 }
424