xref: /freebsd/contrib/less/main.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2015  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	no_init;
61 extern int	pr_type;
62 
63 
64 /*
65  * Entry point.
66  */
67 int
68 main(argc, argv)
69 	int argc;
70 	char *argv[];
71 {
72 	IFILE ifile;
73 	char *s;
74 	extern char *__progname;
75 
76 #ifdef __EMX__
77 	_response(&argc, &argv);
78 	_wildcard(&argc, &argv);
79 #endif
80 
81 	progname = *argv++;
82 	argc--;
83 
84 	secure = 0;
85 	s = lgetenv("LESSSECURE");
86 	if (s != NULL && *s != '\0')
87 		secure = 1;
88 
89 #ifdef WIN32
90 	if (getenv("HOME") == NULL)
91 	{
92 		/*
93 		 * If there is no HOME environment variable,
94 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
95 		 */
96 		char *drive = getenv("HOMEDRIVE");
97 		char *path  = getenv("HOMEPATH");
98 		if (drive != NULL && path != NULL)
99 		{
100 			char *env = (char *) ecalloc(strlen(drive) +
101 					strlen(path) + 6, sizeof(char));
102 			strcpy(env, "HOME=");
103 			strcat(env, drive);
104 			strcat(env, path);
105 			putenv(env);
106 		}
107 	}
108 	GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
109 #endif /* WIN32 */
110 
111 	/*
112 	 * Process command line arguments and LESS environment arguments.
113 	 * Command line arguments override environment arguments.
114 	 */
115 	is_tty = isatty(1);
116 	get_term();
117 	init_cmds();
118 	init_charset();
119 	init_line();
120 	init_cmdhist();
121 	init_option();
122 	init_search();
123 
124 	/*
125 	 * If the name of the executable program is "more",
126 	 * act like LESS_IS_MORE is set.
127 	 */
128 	for (s = progname + strlen(progname);  s > progname;  s--)
129 	{
130 		if (s[-1] == PATHNAME_SEP[0])
131 			break;
132 	}
133 	if (strcmp(s, "more") == 0)
134 		less_is_more = 1;
135 
136 	init_prompt();
137 
138 	if (less_is_more)
139 		scan_option("-fG");
140 
141 	s = lgetenv(less_is_more ? "MORE" : "LESS");
142 	if (s != NULL)
143 		scan_option(save(s));
144 
145 #define	isoptstring(s)	less_is_more   ? (((s)[0] == '-') && (s)[1] != '\0') : \
146 			(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
147 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
148 	{
149 		s = *argv++;
150 		argc--;
151 		if (strcmp(s, "--") == 0)
152 			break;
153 		scan_option(s);
154 	}
155 #undef isoptstring
156 
157 	if (isoptpending())
158 	{
159 		/*
160 		 * Last command line option was a flag requiring a
161 		 * following string, but there was no following string.
162 		 */
163 		nopendopt();
164 		quit(QUIT_OK);
165 	}
166 
167 	if (less_is_more)
168 		no_init = TRUE;
169 
170 #if EDITOR
171 	editor = lgetenv("VISUAL");
172 	if (editor == NULL || *editor == '\0')
173 	{
174 		editor = lgetenv("EDITOR");
175 		if (editor == NULL || *editor == '\0')
176 			editor = EDIT_PGM;
177 	}
178 	editproto = lgetenv("LESSEDIT");
179 	if (editproto == NULL || *editproto == '\0')
180 		editproto = "%E ?lm+%lm. %f";
181 #endif
182 
183 	/*
184 	 * Call get_ifile with all the command line filenames
185 	 * to "register" them with the ifile system.
186 	 */
187 	ifile = NULL_IFILE;
188 	if (dohelp)
189 		ifile = get_ifile(FAKE_HELPFILE, ifile);
190 	while (argc-- > 0)
191 	{
192 		char *filename;
193 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
194 		/*
195 		 * Because the "shell" doesn't expand filename patterns,
196 		 * treat each argument as a filename pattern rather than
197 		 * a single filename.
198 		 * Expand the pattern and iterate over the expanded list.
199 		 */
200 		struct textlist tlist;
201 		char *gfilename;
202 
203 		gfilename = lglob(*argv++);
204 		init_textlist(&tlist, gfilename);
205 		filename = NULL;
206 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
207 		{
208 			(void) get_ifile(filename, ifile);
209 			ifile = prev_ifile(NULL_IFILE);
210 		}
211 		free(gfilename);
212 #else
213 		filename = shell_quote(*argv);
214 		if (filename == NULL)
215 			filename = *argv;
216 		argv++;
217 		(void) get_ifile(filename, ifile);
218 		ifile = prev_ifile(NULL_IFILE);
219 		free(filename);
220 #endif
221 	}
222 	/*
223 	 * Set up terminal, etc.
224 	 */
225 	if (!is_tty)
226 	{
227 		/*
228 		 * Output is not a tty.
229 		 * Just copy the input file(s) to output.
230 		 */
231 		SET_BINARY(1);
232 		if (nifile() == 0)
233 		{
234 			if (edit_stdin() == 0)
235 				cat_file();
236 		} else if (edit_first() == 0)
237 		{
238 			do {
239 				cat_file();
240 			} while (edit_next(1) == 0);
241 		}
242 		quit(QUIT_OK);
243 	}
244 
245 	if (missing_cap && !know_dumb && !less_is_more)
246 		error("WARNING: terminal is not fully functional", NULL_PARG);
247 	init_mark();
248 	open_getchr();
249 	raw_mode(1);
250 	init_signals(1);
251 
252 	/*
253 	 * Select the first file to examine.
254 	 */
255 #if TAGS
256 	if (tagoption != NULL || strcmp(tags, "-") == 0)
257 	{
258 		/*
259 		 * A -t option was given.
260 		 * Verify that no filenames were also given.
261 		 * Edit the file selected by the "tags" search,
262 		 * and search for the proper line in the file.
263 		 */
264 		if (nifile() > 0)
265 		{
266 			error("No filenames allowed with -t option", NULL_PARG);
267 			quit(QUIT_ERROR);
268 		}
269 		findtag(tagoption);
270 		if (edit_tagfile())  /* Edit file which contains the tag */
271 			quit(QUIT_ERROR);
272 		/*
273 		 * Search for the line which contains the tag.
274 		 * Set up initial_scrpos so we display that line.
275 		 */
276 		initial_scrpos.pos = tagsearch();
277 		if (initial_scrpos.pos == NULL_POSITION)
278 			quit(QUIT_ERROR);
279 		initial_scrpos.ln = jump_sline;
280 	} else
281 #endif
282 	if (nifile() == 0)
283 	{
284 		if (edit_stdin())  /* Edit standard input */
285 			quit(QUIT_ERROR);
286 	} else
287 	{
288 		if (edit_first())  /* Edit first valid file in cmd line */
289 			quit(QUIT_ERROR);
290 	}
291 
292 	init();
293 	commands();
294 	quit(QUIT_OK);
295 	/*NOTREACHED*/
296 	return (0);
297 }
298 
299 /*
300  * Copy a string to a "safe" place
301  * (that is, to a buffer allocated by calloc).
302  */
303 	public char *
304 save(s)
305 	char *s;
306 {
307 	register char *p;
308 
309 	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
310 	strcpy(p, s);
311 	return (p);
312 }
313 
314 /*
315  * Allocate memory.
316  * Like calloc(), but never returns an error (NULL).
317  */
318 	public VOID_POINTER
319 ecalloc(count, size)
320 	int count;
321 	unsigned int size;
322 {
323 	register VOID_POINTER p;
324 
325 	p = (VOID_POINTER) calloc(count, size);
326 	if (p != NULL)
327 		return (p);
328 	error("Cannot allocate memory", NULL_PARG);
329 	quit(QUIT_ERROR);
330 	/*NOTREACHED*/
331 	return (NULL);
332 }
333 
334 /*
335  * Skip leading spaces in a string.
336  */
337 	public char *
338 skipsp(s)
339 	register char *s;
340 {
341 	while (*s == ' ' || *s == '\t')
342 		s++;
343 	return (s);
344 }
345 
346 /*
347  * See how many characters of two strings are identical.
348  * If uppercase is true, the first string must begin with an uppercase
349  * character; the remainder of the first string may be either case.
350  */
351 	public int
352 sprefix(ps, s, uppercase)
353 	char *ps;
354 	char *s;
355 	int uppercase;
356 {
357 	register int c;
358 	register int sc;
359 	register int len = 0;
360 
361 	for ( ;  *s != '\0';  s++, ps++)
362 	{
363 		c = *ps;
364 		if (uppercase)
365 		{
366 			if (len == 0 && ASCII_IS_LOWER(c))
367 				return (-1);
368 			if (ASCII_IS_UPPER(c))
369 				c = ASCII_TO_LOWER(c);
370 		}
371 		sc = *s;
372 		if (len > 0 && ASCII_IS_UPPER(sc))
373 			sc = ASCII_TO_LOWER(sc);
374 		if (c != sc)
375 			break;
376 		len++;
377 	}
378 	return (len);
379 }
380 
381 /*
382  * Exit the program.
383  */
384 	public void
385 quit(status)
386 	int status;
387 {
388 	static int save_status;
389 
390 	/*
391 	 * Put cursor at bottom left corner, clear the line,
392 	 * reset the terminal modes, and exit.
393 	 */
394 	if (status < 0)
395 		status = save_status;
396 	else
397 		save_status = status;
398 	quitting = 1;
399 	edit((char*)NULL);
400 	save_cmdhist();
401 	if (any_display && is_tty)
402 		clear_bot();
403 	deinit();
404 	flush();
405 	raw_mode(0);
406 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
407 	/*
408 	 * If we don't close 2, we get some garbage from
409 	 * 2's buffer when it flushes automatically.
410 	 * I cannot track this one down  RB
411 	 * The same bug shows up if we use ^C^C to abort.
412 	 */
413 	close(2);
414 #endif
415 #ifdef WIN32
416 	SetConsoleTitle(consoleTitle);
417 #endif
418 	close_getchr();
419 	exit(status);
420 }
421