main.c revision 294286 
1/* $FreeBSD: stable/10/contrib/less/main.c 294286 2016-01-18 19:13:54Z delphij $ */
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
21public char *	every_first_cmd = NULL;
22public int	new_file;
23public int	is_tty;
24public IFILE	curr_ifile = NULL_IFILE;
25public IFILE	old_ifile = NULL_IFILE;
26public struct scrpos initial_scrpos;
27public int	any_display = FALSE;
28public POSITION	start_attnpos = NULL_POSITION;
29public POSITION	end_attnpos = NULL_POSITION;
30public int	wscroll;
31public char *	progname;
32public int	quitting;
33public int	secure;
34public int	dohelp;
35
36#if LOGFILE
37public int	logfile = -1;
38public int	force_logfile = FALSE;
39public char *	namelogfile = NULL;
40#endif
41
42#if EDITOR
43public char *	editor;
44public char *	editproto;
45#endif
46
47#if TAGS
48extern char *	tags;
49extern char *	tagoption;
50extern int	jump_sline;
51#endif
52
53#ifdef WIN32
54static char consoleTitle[256];
55#endif
56
57extern int	less_is_more;
58extern int	missing_cap;
59extern int	know_dumb;
60extern int	no_init;
61extern int	pr_type;
62
63
64/*
65 * Entry point.
66 */
67int
68main(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 *
304save(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
319ecalloc(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 *
338skipsp(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
352sprefix(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
385quit(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