xref: /freebsd/contrib/less/main.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2007  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 
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 #endif
223 	}
224 	/*
225 	 * Set up terminal, etc.
226 	 */
227 	if (!is_tty)
228 	{
229 		/*
230 		 * Output is not a tty.
231 		 * Just copy the input file(s) to output.
232 		 */
233 		SET_BINARY(1);
234 		if (nifile() == 0)
235 		{
236 			if (edit_stdin() == 0)
237 				cat_file();
238 		} else if (edit_first() == 0)
239 		{
240 			do {
241 				cat_file();
242 			} while (edit_next(1) == 0);
243 		}
244 		quit(QUIT_OK);
245 	}
246 
247 	if (missing_cap && !know_dumb && !less_is_more)
248 		error("WARNING: terminal is not fully functional", NULL_PARG);
249 	init_mark();
250 	open_getchr();
251 	raw_mode(1);
252 	init_signals(1);
253 
254 	/*
255 	 * Select the first file to examine.
256 	 */
257 #if TAGS
258 	if (tagoption != NULL || strcmp(tags, "-") == 0)
259 	{
260 		/*
261 		 * A -t option was given.
262 		 * Verify that no filenames were also given.
263 		 * Edit the file selected by the "tags" search,
264 		 * and search for the proper line in the file.
265 		 */
266 		if (nifile() > 0)
267 		{
268 			error("No filenames allowed with -t option", NULL_PARG);
269 			quit(QUIT_ERROR);
270 		}
271 		findtag(tagoption);
272 		if (edit_tagfile())  /* Edit file which contains the tag */
273 			quit(QUIT_ERROR);
274 		/*
275 		 * Search for the line which contains the tag.
276 		 * Set up initial_scrpos so we display that line.
277 		 */
278 		initial_scrpos.pos = tagsearch();
279 		if (initial_scrpos.pos == NULL_POSITION)
280 			quit(QUIT_ERROR);
281 		initial_scrpos.ln = jump_sline;
282 	} else
283 #endif
284 	if (nifile() == 0)
285 	{
286 		if (edit_stdin())  /* Edit standard input */
287 			quit(QUIT_ERROR);
288 	} else
289 	{
290 		if (edit_first())  /* Edit first valid file in cmd line */
291 			quit(QUIT_ERROR);
292 	}
293 
294 	init();
295 	commands();
296 	quit(QUIT_OK);
297 	/*NOTREACHED*/
298 	return (0);
299 }
300 
301 /*
302  * Copy a string to a "safe" place
303  * (that is, to a buffer allocated by calloc).
304  */
305 	public char *
306 save(s)
307 	char *s;
308 {
309 	register char *p;
310 
311 	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
312 	strcpy(p, s);
313 	return (p);
314 }
315 
316 /*
317  * Allocate memory.
318  * Like calloc(), but never returns an error (NULL).
319  */
320 	public VOID_POINTER
321 ecalloc(count, size)
322 	int count;
323 	unsigned int size;
324 {
325 	register VOID_POINTER p;
326 
327 	p = (VOID_POINTER) calloc(count, size);
328 	if (p != NULL)
329 		return (p);
330 	error("Cannot allocate memory", NULL_PARG);
331 	quit(QUIT_ERROR);
332 	/*NOTREACHED*/
333 	return (NULL);
334 }
335 
336 /*
337  * Skip leading spaces in a string.
338  */
339 	public char *
340 skipsp(s)
341 	register char *s;
342 {
343 	while (*s == ' ' || *s == '\t')
344 		s++;
345 	return (s);
346 }
347 
348 /*
349  * See how many characters of two strings are identical.
350  * If uppercase is true, the first string must begin with an uppercase
351  * character; the remainder of the first string may be either case.
352  */
353 	public int
354 sprefix(ps, s, uppercase)
355 	char *ps;
356 	char *s;
357 	int uppercase;
358 {
359 	register int c;
360 	register int sc;
361 	register int len = 0;
362 
363 	for ( ;  *s != '\0';  s++, ps++)
364 	{
365 		c = *ps;
366 		if (uppercase)
367 		{
368 			if (len == 0 && ASCII_IS_LOWER(c))
369 				return (-1);
370 			if (ASCII_IS_UPPER(c))
371 				c = ASCII_TO_LOWER(c);
372 		}
373 		sc = *s;
374 		if (len > 0 && ASCII_IS_UPPER(sc))
375 			sc = ASCII_TO_LOWER(sc);
376 		if (c != sc)
377 			break;
378 		len++;
379 	}
380 	return (len);
381 }
382 
383 /*
384  * Exit the program.
385  */
386 	public void
387 quit(status)
388 	int status;
389 {
390 	static int save_status;
391 
392 	/*
393 	 * Put cursor at bottom left corner, clear the line,
394 	 * reset the terminal modes, and exit.
395 	 */
396 	if (status < 0)
397 		status = save_status;
398 	else
399 		save_status = status;
400 	quitting = 1;
401 	edit((char*)NULL);
402 	save_cmdhist();
403 	if (any_display && is_tty)
404 		clear_bot();
405 	deinit();
406 	flush();
407 	raw_mode(0);
408 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
409 	/*
410 	 * If we don't close 2, we get some garbage from
411 	 * 2's buffer when it flushes automatically.
412 	 * I cannot track this one down  RB
413 	 * The same bug shows up if we use ^C^C to abort.
414 	 */
415 	close(2);
416 #endif
417 #if WIN32
418 	SetConsoleTitle(consoleTitle);
419 #endif
420 	close_getchr();
421 	exit(status);
422 }
423