[unix-history] / usr.bin / more / main.c

/*
 * Copyright (c) 1988 Mark Nudleman
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1988 Mark Nudleman.\n\
@(#) Copyright (c) 1988 Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)main.c	5.13 (Berkeley) 6/1/90";
#endif /* not lint */

/*
 * Entry point, initialization, miscellaneous routines.
 */

#include <sys/types.h>
#include <sys/file.h>
#include <stdio.h>
#include <less.h>

int	ispipe;
int	new_file;
int	is_tty;
char	*current_file, *previous_file, *current_name, *next_name;
off_t	prev_pos;
int	any_display;
int	scroll;
int	ac;
char	**av;
int	curr_ac;
int	quitting;

extern int	file;
extern int	cbufs;
extern int	errmsgs;

extern char	*tagfile;
extern int	tagoption;

/*
 * Edit a new file.
 * Filename "-" means standard input.
 * No filename means the "current" file, from the command line.
 */
edit(filename)
	register char *filename;
{
	extern int errno;
	register int f;
	register char *m;
	off_t initial_pos, position();
	static int didpipe;
	char message[100], *p;
	char *rindex(), *strerror(), *save(), *bad_file();

	initial_pos = NULL_POSITION;
	if (filename == NULL || *filename == '\0') {
		if (curr_ac >= ac) {
			error("No current file");
			return(0);
		}
		filename = save(av[curr_ac]);
	}
	else if (strcmp(filename, "#") == 0) {
		if (*previous_file == '\0') {
			error("no previous file");
			return(0);
		}
		filename = save(previous_file);
		initial_pos = prev_pos;
	} else
		filename = save(filename);

	/* use standard input. */
	if (!strcmp(filename, "-")) {
		if (didpipe) {
			error("Can view standard input only once");
			return(0);
		}
		f = 0;
	}
	else if ((m = bad_file(filename, message, sizeof(message))) != NULL) {
		error(m);
		free(filename);
		return(0);
	}
	else if ((f = open(filename, O_RDONLY, 0)) < 0) {
		(void)sprintf(message, "%s: %s", filename, strerror(errno));
		error(message);
		free(filename);
		return(0);
	}

	if (isatty(f)) {
		/*
		 * Not really necessary to call this an error,
		 * but if the control terminal (for commands)
		 * and the input file (for data) are the same,
		 * we get weird results at best.
		 */
		error("Can't take input from a terminal");
		if (f > 0)
			(void)close(f);
		(void)free(filename);
		return(0);
	}

	/*
	 * We are now committed to using the new file.
	 * Close the current input file and set up to use the new one.
	 */
	if (file > 0)
		(void)close(file);
	new_file = 1;
	if (previous_file != NULL)
		free(previous_file);
	previous_file = current_file;
	current_file = filename;
	pos_clear();
	prev_pos = position(TOP);
	ispipe = (f == 0);
	if (ispipe) {
		didpipe = 1;
		current_name = "stdin";
	} else
		current_name = (p = rindex(filename, '/')) ? p + 1 : filename;
	if (curr_ac >= ac)
		next_name = NULL;
	else
		next_name = av[curr_ac + 1];
	file = f;
	ch_init(cbufs, 0);
	init_mark();

	if (is_tty) {
		int no_display = !any_display;
		any_display = 1;
		if (no_display && errmsgs > 0) {
			/*
			 * We displayed some messages on error output
			 * (file descriptor 2; see error() function).
			 * Before erasing the screen contents,
			 * display the file name and wait for a keystroke.
			 */
			error(filename);
		}
		/*
		 * Indicate there is nothing displayed yet.
		 */
		if (initial_pos != NULL_POSITION)
			jump_loc(initial_pos);
		clr_linenum();
	}
	return(1);
}

/*
 * Edit the next file in the command line list.
 */
next_file(n)
	int n;
{
	extern int quit_at_eof;
	off_t position();

	if (curr_ac + n >= ac) {
		if (quit_at_eof || position(TOP) == NULL_POSITION)
			quit();
		error("No (N-th) next file");
	}
	else
		(void)edit(av[curr_ac += n]);
}

/*
 * Edit the previous file in the command line list.
 */
prev_file(n)
	int n;
{
	if (curr_ac - n < 0)
		error("No (N-th) previous file");
	else
		(void)edit(av[curr_ac -= n]);
}

/*
 * copy a file directly to standard output; used if stdout is not a tty.
 * the only processing is to squeeze multiple blank input lines.
 */
static
cat_file()
{
	extern int squeeze;
	register int c, empty;

	if (squeeze) {
		empty = 0;
		while ((c = ch_forw_get()) != EOI)
			if (c != '\n') {
				putchr(c);
				empty = 0;
			}
			else if (empty < 2) {
				putchr(c);
				++empty;
			}
	}
	else while ((c = ch_forw_get()) != EOI)
		putchr(c);
	flush();
}

main(argc, argv)
	int argc;
	char **argv;
{
	int envargc, argcnt;
	char *envargv[2], *getenv();

	/*
	 * Process command line arguments and MORE environment arguments.
	 * Command line arguments override environment arguments.
	 */
	if (envargv[1] = getenv("MORE")) {
		envargc = 2;
		envargv[0] = "more";
		envargv[2] = NULL;
		(void)option(envargc, envargv);
	}
	argcnt = option(argc, argv);
	argv += argcnt;
	argc -= argcnt;

	/*
	 * Set up list of files to be examined.
	 */
	ac = argc;
	av = argv;
	curr_ac = 0;

	/*
	 * Set up terminal, etc.
	 */
	is_tty = isatty(1);
	if (!is_tty) {
		/*
		 * Output is not a tty.
		 * Just copy the input file(s) to output.
		 */
		if (ac < 1) {
			(void)edit("-");
			cat_file();
		} else {
			do {
				(void)edit((char *)NULL);
				if (file >= 0)
					cat_file();
			} while (++curr_ac < ac);
		}
		exit(0);
	}

	raw_mode(1);
	get_term();
	open_getchr();
	init();
	init_signals(1);

	/* select the first file to examine. */
	if (tagoption) {
		/*
		 * A -t option was given; edit the file selected by the
		 * "tags" search, and search for the proper line in the file.
		 */
		if (!tagfile || !edit(tagfile) || tagsearch())
			quit();
	}
	else if (ac < 1)
		(void)edit("-");	/* Standard input */
	else {
		/*
		 * Try all the files named as command arguments.
		 * We are simply looking for one which can be
		 * opened without error.
		 */
		do {
			(void)edit((char *)NULL);
		} while (file < 0 && ++curr_ac < ac);
	}

	if (file >= 0)
		commands();
	quit();
	/*NOTREACHED*/
}

/*
 * Copy a string to a "safe" place
 * (that is, to a buffer allocated by malloc).
 */
char *
save(s)
	char *s;
{
	char *p, *strcpy(), *malloc();

	p = malloc((u_int)strlen(s)+1);
	if (p == NULL)
	{
		error("cannot allocate memory");
		quit();
	}
	return(strcpy(p, s));
}

/*
 * Exit the program.
 */
quit()
{
	/*
	 * Put cursor at bottom left corner, clear the line,
	 * reset the terminal modes, and exit.
	 */
	quitting = 1;
	lower_left();
	clear_eol();
	deinit();
	flush();
	raw_mode(0);
	exit(0);
}
Commit	Line	Data
2ec5f51d NW	1	/*
	2	* Copyright (c) 1988 Mark Nudleman
	3	* Copyright (c) 1988 Regents of the University of California.
	4	* All rights reserved.
	5	*
	6	* Redistribution and use in source and binary forms, with or without
	7	* modification, are permitted provided that the following conditions
	8	* are met:
	9	* 1. Redistributions of source code must retain the above copyright
	10	* notice, this list of conditions and the following disclaimer.
	11	* 2. Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
	14	* 3. All advertising materials mentioning features or use of this software
	15	* must display the following acknowledgement:
	16	* This product includes software developed by the University of
	17	* California, Berkeley and its contributors.
	18	* 4. Neither the name of the University nor the names of its contributors
	19	* may be used to endorse or promote products derived from this software
	20	* without specific prior written permission.
	21	*
	22	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	23	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	24	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	25	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	26	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	27	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	28	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	29	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	30	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	31	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	32	* SUCH DAMAGE.
	33	*/
	34
	35	#ifndef lint
	36	char copyright[] =
	37	"@(#) Copyright (c) 1988 Mark Nudleman.\n\
	38	@(#) Copyright (c) 1988 Regents of the University of California.\n\
	39	All rights reserved.\n";
	40	#endif /* not lint */
	41
	42	#ifndef lint
	43	static char sccsid[] = "@(#)main.c 5.13 (Berkeley) 6/1/90";
	44	#endif /* not lint */
	45
	46	/*
	47	* Entry point, initialization, miscellaneous routines.
	48	*/
	49
	50	#include <sys/types.h>
	51	#include <sys/file.h>
	52	#include <stdio.h>
	53	#include <less.h>
	54
	55	int ispipe;
	56	int new_file;
	57	int is_tty;
	58	char current_file, previous_file, current_name, next_name;
	59	off_t prev_pos;
	60	int any_display;
	61	int scroll;
	62	int ac;
	63	char **av;
	64	int curr_ac;
65	int quitting;
66
67	extern int file;
68	extern int cbufs;
69	extern int errmsgs;
70
71	extern char *tagfile;
72	extern int tagoption;
73
74	/*
75	* Edit a new file.
76	* Filename "-" means standard input.
77	* No filename means the "current" file, from the command line.
78	*/
79	edit(filename)
80	register char *filename;
81	{
82	extern int errno;
83	register int f;
84	register char *m;
85	off_t initial_pos, position();
86	static int didpipe;
87	char message[100], *p;
88	char rindex(), strerror(), save(), bad_file();
89
90	initial_pos = NULL_POSITION;
91	if (filename == NULL \|\| *filename == '\0') {
92	if (curr_ac >= ac) {
93	error("No current file");
94	return(0);
95	}
96	filename = save(av[curr_ac]);
97	}
98	else if (strcmp(filename, "#") == 0) {
99	if (*previous_file == '\0') {
100	error("no previous file");
101	return(0);
102	}
103	filename = save(previous_file);
104	initial_pos = prev_pos;
105	} else
106	filename = save(filename);
107
108	/* use standard input. */
109	if (!strcmp(filename, "-")) {
110	if (didpipe) {
111	error("Can view standard input only once");
112	return(0);
113	}
114	f = 0;
115	}
116	else if ((m = bad_file(filename, message, sizeof(message))) != NULL) {
117	error(m);
118	free(filename);
119	return(0);
120	}
121	else if ((f = open(filename, O_RDONLY, 0)) < 0) {
122	(void)sprintf(message, "%s: %s", filename, strerror(errno));
123	error(message);
124	free(filename);
125	return(0);
126	}
127
128	if (isatty(f)) {
129	/*
130	* Not really necessary to call this an error,
131	* but if the control terminal (for commands)
132	* and the input file (for data) are the same,
133	* we get weird results at best.
134	*/
135	error("Can't take input from a terminal");
136	if (f > 0)
137	(void)close(f);
138	(void)free(filename);
139	return(0);
140	}
141
142	/*
143	* We are now committed to using the new file.
144	* Close the current input file and set up to use the new one.
145	*/
146	if (file > 0)
147	(void)close(file);
148	new_file = 1;
149	if (previous_file != NULL)
150	free(previous_file);
151	previous_file = current_file;
152	current_file = filename;
153	pos_clear();
154	prev_pos = position(TOP);
155	ispipe = (f == 0);
156	if (ispipe) {
157	didpipe = 1;
158	current_name = "stdin";
159	} else
160	current_name = (p = rindex(filename, '/')) ? p + 1 : filename;
161	if (curr_ac >= ac)
162	next_name = NULL;
163	else
164	next_name = av[curr_ac + 1];
165	file = f;
166	ch_init(cbufs, 0);
167	init_mark();
168
169	if (is_tty) {
170	int no_display = !any_display;
171	any_display = 1;
172	if (no_display && errmsgs > 0) {
173	/*
174	* We displayed some messages on error output
175	* (file descriptor 2; see error() function).
176	* Before erasing the screen contents,
177	* display the file name and wait for a keystroke.
178	*/
179	error(filename);
180	}
181	/*
182	* Indicate there is nothing displayed yet.
183	*/
184	if (initial_pos != NULL_POSITION)
185	jump_loc(initial_pos);
186	clr_linenum();
187	}
188	return(1);
189	}
190
191	/*
192	* Edit the next file in the command line list.
193	*/
194	next_file(n)
195	int n;
196	{
197	extern int quit_at_eof;
198	off_t position();
199
200	if (curr_ac + n >= ac) {
201	if (quit_at_eof \|\| position(TOP) == NULL_POSITION)
202	quit();
203	error("No (N-th) next file");
204	}
205	else
206	(void)edit(av[curr_ac += n]);
207	}
208
209	/*
210	* Edit the previous file in the command line list.
211	*/
212	prev_file(n)
213	int n;
214	{
215	if (curr_ac - n < 0)
216	error("No (N-th) previous file");
217	else
218	(void)edit(av[curr_ac -= n]);
219	}
220
221	/*
222	* copy a file directly to standard output; used if stdout is not a tty.
223	* the only processing is to squeeze multiple blank input lines.
224	*/
225	static
226	cat_file()
227	{
228	extern int squeeze;
229	register int c, empty;
230
231	if (squeeze) {
232	empty = 0;
233	while ((c = ch_forw_get()) != EOI)
234	if (c != '\n') {
235	putchr(c);
236	empty = 0;
237	}
238	else if (empty < 2) {
239	putchr(c);
240	++empty;
241	}
242	}
243	else while ((c = ch_forw_get()) != EOI)
244	putchr(c);
245	flush();
246	}
247
248	main(argc, argv)
249	int argc;
250	char **argv;
251	{
252	int envargc, argcnt;
253	char envargv[2], getenv();
254
255	/*
256	* Process command line arguments and MORE environment arguments.
257	* Command line arguments override environment arguments.
258	*/
259	if (envargv[1] = getenv("MORE")) {
260	envargc = 2;
261	envargv[0] = "more";
262	envargv[2] = NULL;
263	(void)option(envargc, envargv);
264	}
265	argcnt = option(argc, argv);
266	argv += argcnt;
267	argc -= argcnt;
268
269	/*
270	* Set up list of files to be examined.
271	*/
272	ac = argc;
273	av = argv;
274	curr_ac = 0;
275
276	/*
277	* Set up terminal, etc.
278	*/
279	is_tty = isatty(1);
280	if (!is_tty) {
281	/*
282	* Output is not a tty.
283	* Just copy the input file(s) to output.
284	*/
285	if (ac < 1) {
286	(void)edit("-");
287	cat_file();
288	} else {
289	do {
290	(void)edit((char *)NULL);
291	if (file >= 0)
292	cat_file();
293	} while (++curr_ac < ac);
294	}
295	exit(0);
296	}
297
298	raw_mode(1);
299	get_term();
300	open_getchr();
301	init();
302	init_signals(1);
303
304	/* select the first file to examine. */
305	if (tagoption) {
306	/*
307	* A -t option was given; edit the file selected by the
308	* "tags" search, and search for the proper line in the file.
309	*/
310	if (!tagfile \|\| !edit(tagfile) \|\| tagsearch())
311	quit();
312	}
313	else if (ac < 1)
314	(void)edit("-"); /* Standard input */
315	else {
316	/*
317	* Try all the files named as command arguments.
318	* We are simply looking for one which can be
319	* opened without error.
320	*/
321	do {
322	(void)edit((char *)NULL);
323	} while (file < 0 && ++curr_ac < ac);
324	}
325
326	if (file >= 0)
327	commands();
328	quit();
329	/NOTREACHED/
330	}
331
332	/*
333	* Copy a string to a "safe" place
334	* (that is, to a buffer allocated by malloc).
335	*/
336	char *
337	save(s)
338	char *s;
339	{
340	char p, strcpy(), *malloc();
341
342	p = malloc((u_int)strlen(s)+1);
343	if (p == NULL)
344	{
345	error("cannot allocate memory");
346	quit();
347	}
348	return(strcpy(p, s));
349	}
350
351	/*
352	* Exit the program.
353	*/
354	quit()
355	{
356	/*
357	* Put cursor at bottom left corner, clear the line,
358	* reset the terminal modes, and exit.
359	*/
360	quitting = 1;
361	lower_left();
362	clear_eol();
363	deinit();
364	flush();
365	raw_mode(0);
366	exit(0);
367	}