xref: /dragonfly/contrib/less/main.c (revision ae071d8d)
1 /*
2  * Copyright (C) 1984-2012  Mark Nudelman
3  *
4  * You may distribute under the terms of either the GNU General Public
5  * License or the Less License, as specified in the README file.
6  *
7  * For more information, see the README file.
8  */
9 
10 
11 /*
12  * Entry point, initialization, miscellaneous routines.
13  */
14 
15 #include "less.h"
16 #if MSDOS_COMPILER==WIN32C
17 #include <windows.h>
18 #endif
19 
20 public char *	every_first_cmd = NULL;
21 public int	new_file;
22 public int	is_tty;
23 public IFILE	curr_ifile = NULL_IFILE;
24 public IFILE	old_ifile = NULL_IFILE;
25 public struct scrpos initial_scrpos;
26 public int	any_display = FALSE;
27 public POSITION	start_attnpos = NULL_POSITION;
28 public POSITION	end_attnpos = NULL_POSITION;
29 public int	wscroll;
30 public char *	progname;
31 public int	quitting;
32 public int	secure;
33 public int	dohelp;
34 
35 #if LOGFILE
36 public int	logfile = -1;
37 public int	force_logfile = FALSE;
38 public char *	namelogfile = NULL;
39 #endif
40 
41 #if EDITOR
42 public char *	editor;
43 public char *	editproto;
44 #endif
45 
46 #if TAGS
47 extern char *	tags;
48 extern char *	tagoption;
49 extern int	jump_sline;
50 #endif
51 
52 #ifdef WIN32
53 static char consoleTitle[256];
54 #endif
55 
56 extern int	less_is_more;
57 extern int	missing_cap;
58 extern int	know_dumb;
59 extern int	quit_if_one_screen;
60 extern int	pr_type;
61 
62 
63 /*
64  * Entry point.
65  */
66 int
67 main(argc, argv)
68 	int argc;
69 	char *argv[];
70 {
71 	IFILE ifile;
72 	char *s;
73 
74 #ifdef __EMX__
75 	_response(&argc, &argv);
76 	_wildcard(&argc, &argv);
77 #endif
78 
79 	progname = *argv++;
80 	argc--;
81 
82 	secure = 0;
83 	s = lgetenv("LESSSECURE");
84 	if (s != NULL && *s != '\0')
85 		secure = 1;
86 
87 #ifdef WIN32
88 	if (getenv("HOME") == NULL)
89 	{
90 		/*
91 		 * If there is no HOME environment variable,
92 		 * try the concatenation of HOMEDRIVE + HOMEPATH.
93 		 */
94 		char *drive = getenv("HOMEDRIVE");
95 		char *path  = getenv("HOMEPATH");
96 		if (drive != NULL && path != NULL)
97 		{
98 			char *env = (char *) ecalloc(strlen(drive) +
99 					strlen(path) + 6, sizeof(char));
100 			strcpy(env, "HOME=");
101 			strcat(env, drive);
102 			strcat(env, path);
103 			putenv(env);
104 		}
105 	}
106 	GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
107 #endif /* WIN32 */
108 
109 	/*
110 	 * Process command line arguments and LESS environment arguments.
111 	 * Command line arguments override environment arguments.
112 	 */
113 	is_tty = isatty(1);
114 	get_term();
115 	init_cmds();
116 	init_charset();
117 	init_line();
118 	init_cmdhist();
119 	init_option();
120 	init_search();
121 
122 	/*
123 	 * If the name of the executable program is "more",
124 	 * act like LESS_IS_MORE is set.
125 	 */
126 	for (s = progname + strlen(progname);  s > progname;  s--)
127 	{
128 		if (s[-1] == PATHNAME_SEP[0])
129 			break;
130 	}
131 	if (strcmp(s, "more") == 0)
132 		less_is_more = 1;
133 
134 	init_prompt();
135 
136 	s = lgetenv(less_is_more ? "MORE" : "LESS");
137 	if (s != NULL)
138 		scan_option(save(s));
139 
140 #define	isoptstring(s)	(((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
141 	while (argc > 0 && (isoptstring(*argv) || isoptpending()))
142 	{
143 		s = *argv++;
144 		argc--;
145 		if (strcmp(s, "--") == 0)
146 			break;
147 		scan_option(s);
148 	}
149 #undef isoptstring
150 
151 	if (isoptpending())
152 	{
153 		/*
154 		 * Last command line option was a flag requiring a
155 		 * following string, but there was no following string.
156 		 */
157 		nopendopt();
158 		quit(QUIT_OK);
159 	}
160 
161 	if (less_is_more && get_quit_at_eof())
162 		quit_if_one_screen = TRUE;
163 
164 #if EDITOR
165 	editor = lgetenv("VISUAL");
166 	if (editor == NULL || *editor == '\0')
167 	{
168 		editor = lgetenv("EDITOR");
169 		if (editor == NULL || *editor == '\0')
170 			editor = EDIT_PGM;
171 	}
172 	editproto = lgetenv("LESSEDIT");
173 	if (editproto == NULL || *editproto == '\0')
174 		editproto = "%E ?lm+%lm. %f";
175 #endif
176 
177 	/*
178 	 * Call get_ifile with all the command line filenames
179 	 * to "register" them with the ifile system.
180 	 */
181 	ifile = NULL_IFILE;
182 	if (dohelp)
183 		ifile = get_ifile(FAKE_HELPFILE, ifile);
184 	while (argc-- > 0)
185 	{
186 		char *filename;
187 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
188 		/*
189 		 * Because the "shell" doesn't expand filename patterns,
190 		 * treat each argument as a filename pattern rather than
191 		 * a single filename.
192 		 * Expand the pattern and iterate over the expanded list.
193 		 */
194 		struct textlist tlist;
195 		char *gfilename;
196 
197 		gfilename = lglob(*argv++);
198 		init_textlist(&tlist, gfilename);
199 		filename = NULL;
200 		while ((filename = forw_textlist(&tlist, filename)) != NULL)
201 		{
202 			(void) get_ifile(filename, ifile);
203 			ifile = prev_ifile(NULL_IFILE);
204 		}
205 		free(gfilename);
206 #else
207 		filename = shell_quote(*argv);
208 		if (filename == NULL)
209 			filename = *argv;
210 		argv++;
211 		(void) get_ifile(filename, ifile);
212 		ifile = prev_ifile(NULL_IFILE);
213 		free(filename);
214 #endif
215 	}
216 	/*
217 	 * Set up terminal, etc.
218 	 */
219 	if (!is_tty)
220 	{
221 		/*
222 		 * Output is not a tty.
223 		 * Just copy the input file(s) to output.
224 		 */
225 		SET_BINARY(1);
226 		if (nifile() == 0)
227 		{
228 			if (edit_stdin() == 0)
229 				cat_file();
230 		} else if (edit_first() == 0)
231 		{
232 			do {
233 				cat_file();
234 			} while (edit_next(1) == 0);
235 		}
236 		quit(QUIT_OK);
237 	}
238 
239 	if (missing_cap && !know_dumb)
240 		error("WARNING: terminal is not fully functional", NULL_PARG);
241 	init_mark();
242 	open_getchr();
243 	raw_mode(1);
244 	init_signals(1);
245 
246 	/*
247 	 * Select the first file to examine.
248 	 */
249 #if TAGS
250 	if (tagoption != NULL || strcmp(tags, "-") == 0)
251 	{
252 		/*
253 		 * A -t option was given.
254 		 * Verify that no filenames were also given.
255 		 * Edit the file selected by the "tags" search,
256 		 * and search for the proper line in the file.
257 		 */
258 		if (nifile() > 0)
259 		{
260 			error("No filenames allowed with -t option", NULL_PARG);
261 			quit(QUIT_ERROR);
262 		}
263 		findtag(tagoption);
264 		if (edit_tagfile())  /* Edit file which contains the tag */
265 			quit(QUIT_ERROR);
266 		/*
267 		 * Search for the line which contains the tag.
268 		 * Set up initial_scrpos so we display that line.
269 		 */
270 		initial_scrpos.pos = tagsearch();
271 		if (initial_scrpos.pos == NULL_POSITION)
272 			quit(QUIT_ERROR);
273 		initial_scrpos.ln = jump_sline;
274 	} else
275 #endif
276 	if (nifile() == 0)
277 	{
278 		if (edit_stdin())  /* Edit standard input */
279 			quit(QUIT_ERROR);
280 	} else
281 	{
282 		if (edit_first())  /* Edit first valid file in cmd line */
283 			quit(QUIT_ERROR);
284 	}
285 
286 	init();
287 	commands();
288 	quit(QUIT_OK);
289 	/*NOTREACHED*/
290 	return (0);
291 }
292 
293 /*
294  * Copy a string to a "safe" place
295  * (that is, to a buffer allocated by calloc).
296  */
297 	public char *
298 save(s)
299 	char *s;
300 {
301 	register char *p;
302 
303 	p = (char *) ecalloc(strlen(s)+1, sizeof(char));
304 	strcpy(p, s);
305 	return (p);
306 }
307 
308 /*
309  * Allocate memory.
310  * Like calloc(), but never returns an error (NULL).
311  */
312 	public VOID_POINTER
313 ecalloc(count, size)
314 	int count;
315 	unsigned int size;
316 {
317 	register VOID_POINTER p;
318 
319 	p = (VOID_POINTER) calloc(count, size);
320 	if (p != NULL)
321 		return (p);
322 	error("Cannot allocate memory", NULL_PARG);
323 	quit(QUIT_ERROR);
324 	/*NOTREACHED*/
325 	return (NULL);
326 }
327 
328 /*
329  * Skip leading spaces in a string.
330  */
331 	public char *
332 skipsp(s)
333 	register char *s;
334 {
335 	while (*s == ' ' || *s == '\t')
336 		s++;
337 	return (s);
338 }
339 
340 /*
341  * See how many characters of two strings are identical.
342  * If uppercase is true, the first string must begin with an uppercase
343  * character; the remainder of the first string may be either case.
344  */
345 	public int
346 sprefix(ps, s, uppercase)
347 	char *ps;
348 	char *s;
349 	int uppercase;
350 {
351 	register int c;
352 	register int sc;
353 	register int len = 0;
354 
355 	for ( ;  *s != '\0';  s++, ps++)
356 	{
357 		c = *ps;
358 		if (uppercase)
359 		{
360 			if (len == 0 && ASCII_IS_LOWER(c))
361 				return (-1);
362 			if (ASCII_IS_UPPER(c))
363 				c = ASCII_TO_LOWER(c);
364 		}
365 		sc = *s;
366 		if (len > 0 && ASCII_IS_UPPER(sc))
367 			sc = ASCII_TO_LOWER(sc);
368 		if (c != sc)
369 			break;
370 		len++;
371 	}
372 	return (len);
373 }
374 
375 /*
376  * Exit the program.
377  */
378 	public void
379 quit(status)
380 	int status;
381 {
382 	static int save_status;
383 
384 	/*
385 	 * Put cursor at bottom left corner, clear the line,
386 	 * reset the terminal modes, and exit.
387 	 */
388 	if (status < 0)
389 		status = save_status;
390 	else
391 		save_status = status;
392 	quitting = 1;
393 	edit((char*)NULL);
394 	save_cmdhist();
395 	if (any_display && is_tty)
396 		clear_bot();
397 	deinit();
398 	flush();
399 	raw_mode(0);
400 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
401 	/*
402 	 * If we don't close 2, we get some garbage from
403 	 * 2's buffer when it flushes automatically.
404 	 * I cannot track this one down  RB
405 	 * The same bug shows up if we use ^C^C to abort.
406 	 */
407 	close(2);
408 #endif
409 #ifdef WIN32
410 	SetConsoleTitle(consoleTitle);
411 #endif
412 	close_getchr();
413 	exit(status);
414 }
415