xref: /freebsd/contrib/less/main.c (revision 1de7b4b805ddbf2429da511c053686ac4591ed89)
1 /* $FreeBSD$ */
2 /*
3  * Copyright (C) 1984-2017  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 public int  line_count;
58 extern int	less_is_more;
59 extern int	missing_cap;
60 extern int	know_dumb;
61 extern int	no_init;
62 extern int	pr_type;
63 extern int	quit_if_one_screen;
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 	init_cmds();
119 	get_term();
120 	expand_cmd_tables();
121 	init_charset();
122 	init_line();
123 	init_cmdhist();
124 	init_option();
125 	init_search();
126 
127 	/*
128 	 * If the name of the executable program is "more",
129 	 * act like LESS_IS_MORE is set.
130 	 */
131 	for (s = progname + strlen(progname);  s > progname;  s--)
132 	{
133 		if (s[-1] == PATHNAME_SEP[0])
134 			break;
135 	}
136 	if (strcmp(s, "more") == 0)
137 		less_is_more = 1;
138 
139 	init_prompt();
140 
141 	if (less_is_more)
142 		scan_option("-fG");
143 
144 	s = lgetenv(less_is_more ? "MORE" : "LESS");
145 	if (s != NULL)
146 		scan_option(save(s));
147 
148 #define	isoptstring(s)	less_is_more   ? (((s)[0] == '-') && (s)[1] != '\0') : \
149 			(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
150 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
151 	{
152 		s = *argv++;
153 		argc--;
154 		if (strcmp(s, "--") == 0)
155 			break;
156 		scan_option(s);
157 	}
158 #undef isoptstring
159 
160 	if (isoptpending())
161 	{
162 		/*
163 		 * Last command line option was a flag requiring a
164 		 * following string, but there was no following string.
165 		 */
166 		nopendopt();
167 		quit(QUIT_OK);
168 	}
169 
170 	if (less_is_more)
171 		no_init = 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 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
196 		/*
197 		 * Because the "shell" doesn't expand filename patterns,
198 		 * treat each argument as a filename pattern rather than
199 		 * a single filename.
200 		 * Expand the pattern and iterate over the expanded list.
201 		 */
202 		struct textlist tlist;
203 		char *filename;
204 		char *gfilename;
205 		char *qfilename;
206 
207 		gfilename = lglob(*argv++);
208 		init_textlist(&tlist, gfilename);
209 		filename = NULL;
210 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
211 		{
212 			qfilename = shell_unquote(filename);
213 			(void) get_ifile(qfilename, ifile);
214 			free(qfilename);
215 			ifile = prev_ifile(NULL_IFILE);
216 		}
217 		free(gfilename);
218 #else
219 		(void) get_ifile(*argv++, ifile);
220 		ifile = prev_ifile(NULL_IFILE);
221 #endif
222 	}
223 	/*
224 	 * Set up terminal, etc.
225 	 */
226 	if (!is_tty)
227 	{
228 		/*
229 		 * Output is not a tty.
230 		 * Just copy the input file(s) to output.
231 		 */
232 		SET_BINARY(1);
233 		if (nifile() == 0)
234 		{
235 			if (edit_stdin() == 0)
236 				cat_file();
237 		} else if (edit_first() == 0)
238 		{
239 			do {
240 				cat_file();
241 			} while (edit_next(1) == 0);
242 		}
243 		quit(QUIT_OK);
244 	}
245 
246 	if (missing_cap && !know_dumb && !less_is_more)
247 		error("WARNING: terminal is not fully functional", NULL_PARG);
248 	init_mark();
249 	open_getchr();
250 	raw_mode(1);
251 	init_signals(1);
252 
253 	/*
254 	 * Select the first file to examine.
255 	 */
256 #if TAGS
257 	if (tagoption != NULL || strcmp(tags, "-") == 0)
258 	{
259 		/*
260 		 * A -t option was given.
261 		 * Verify that no filenames were also given.
262 		 * Edit the file selected by the "tags" search,
263 		 * and search for the proper line in the file.
264 		 */
265 		if (nifile() > 0)
266 		{
267 			error("No filenames allowed with -t option", NULL_PARG);
268 			quit(QUIT_ERROR);
269 		}
270 		findtag(tagoption);
271 		if (edit_tagfile())  /* Edit file which contains the tag */
272 			quit(QUIT_ERROR);
273 		/*
274 		 * Search for the line which contains the tag.
275 		 * Set up initial_scrpos so we display that line.
276 		 */
277 		initial_scrpos.pos = tagsearch();
278 		if (initial_scrpos.pos == NULL_POSITION)
279 			quit(QUIT_ERROR);
280 		initial_scrpos.ln = jump_sline;
281 	} else
282 #endif
283 	if (nifile() == 0)
284 	{
285 		if (edit_stdin())  /* Edit standard input */
286 			quit(QUIT_ERROR);
287 		if (quit_if_one_screen)
288 			line_count = get_line_count();
289 	} else
290 	{
291 		if (edit_first())  /* Edit first valid file in cmd line */
292 			quit(QUIT_ERROR);
293 		if (quit_if_one_screen)
294 		{
295 			if (nifile() == 1)
296 				line_count = get_line_count();
297 			else /* If more than one file, -F can not be used */
298 				quit_if_one_screen = FALSE;
299 		}
300 	}
301 
302 	init();
303 	commands();
304 	quit(QUIT_OK);
305 	/*NOTREACHED*/
306 	return (0);
307 }
308 
309 /*
310  * Copy a string to a "safe" place
311  * (that is, to a buffer allocated by calloc).
312  */
313 	public char *
314 save(s)
315 	constant char *s;
316 {
317 	char *p;
318 
319 	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
320 	strcpy(p, s);
321 	return (p);
322 }
323 
324 /*
325  * Allocate memory.
326  * Like calloc(), but never returns an error (NULL).
327  */
328 	public VOID_POINTER
329 ecalloc(count, size)
330 	int count;
331 	unsigned int size;
332 {
333 	VOID_POINTER p;
334 
335 	p = (VOID_POINTER) calloc(count, size);
336 	if (p != NULL)
337 		return (p);
338 	error("Cannot allocate memory", NULL_PARG);
339 	quit(QUIT_ERROR);
340 	/*NOTREACHED*/
341 	return (NULL);
342 }
343 
344 /*
345  * Skip leading spaces in a string.
346  */
347 	public char *
348 skipsp(s)
349 	char *s;
350 {
351 	while (*s == ' ' || *s == '\t')
352 		s++;
353 	return (s);
354 }
355 
356 /*
357  * See how many characters of two strings are identical.
358  * If uppercase is true, the first string must begin with an uppercase
359  * character; the remainder of the first string may be either case.
360  */
361 	public int
362 sprefix(ps, s, uppercase)
363 	char *ps;
364 	char *s;
365 	int uppercase;
366 {
367 	int c;
368 	int sc;
369 	int len = 0;
370 
371 	for ( ;  *s != '\0';  s++, ps++)
372 	{
373 		c = *ps;
374 		if (uppercase)
375 		{
376 			if (len == 0 && ASCII_IS_LOWER(c))
377 				return (-1);
378 			if (ASCII_IS_UPPER(c))
379 				c = ASCII_TO_LOWER(c);
380 		}
381 		sc = *s;
382 		if (len > 0 && ASCII_IS_UPPER(sc))
383 			sc = ASCII_TO_LOWER(sc);
384 		if (c != sc)
385 			break;
386 		len++;
387 	}
388 	return (len);
389 }
390 
391 /*
392  * Exit the program.
393  */
394 	public void
395 quit(status)
396 	int status;
397 {
398 	static int save_status;
399 
400 	/*
401 	 * Put cursor at bottom left corner, clear the line,
402 	 * reset the terminal modes, and exit.
403 	 */
404 	if (status < 0)
405 		status = save_status;
406 	else
407 		save_status = status;
408 	quitting = 1;
409 	edit((char*)NULL);
410 	save_cmdhist();
411 	if (any_display && is_tty)
412 		clear_bot();
413 	deinit();
414 	flush();
415 	raw_mode(0);
416 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
417 	/*
418 	 * If we don't close 2, we get some garbage from
419 	 * 2's buffer when it flushes automatically.
420 	 * I cannot track this one down  RB
421 	 * The same bug shows up if we use ^C^C to abort.
422 	 */
423 	close(2);
424 #endif
425 #ifdef WIN32
426 	SetConsoleTitle(consoleTitle);
427 #endif
428 	close_getchr();
429 	exit(status);
430 }
431