aboutsummaryrefslogtreecommitdiff
path: root/util-linux/more.c
blob: 1ec3007bfb721a6fad175ada952face9b621e372 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
/* vi: set sw=4 ts=4: */
/*
 * Mini more implementation for busybox
 *
 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
 * Copyright (C) 1999-2003 by Erik Andersen <andersen@codepoet.org>
 *
 * Latest version blended together by Erik Andersen <andersen@codepoet.org>,
 * based on the original more implementation by Bruce, and code from the 
 * Debian boot-floppies team.
 *
 * Termios corrects by Vladimir Oleynik <dzo@simtreas.ru>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include <stdio.h>
#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include "busybox.h"

static FILE *cin;

#ifdef CONFIG_FEATURE_USE_TERMIOS
#include <termios.h>
#define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
#define getTermSettings(fd,argp) tcgetattr(fd, argp);

static struct termios initial_settings, new_settings;

static void set_tty_to_initial_mode(void)
{
	setTermSettings(fileno(cin), &initial_settings);
}

static void gotsig(int sig)
{
	putchar('\n');
	exit(EXIT_FAILURE);
}
#endif /* CONFIG_FEATURE_USE_TERMIOS */


static int terminal_width = 79;	/* not 80 in case terminal has linefold bug */
static int terminal_height = 24;


extern int more_main(int argc, char **argv)
{
	int c, lines, input = 0;
	int please_display_more_prompt = -1;
	struct stat st;
	FILE *file;
	int len, page_height;

#if defined CONFIG_FEATURE_AUTOWIDTH && defined CONFIG_FEATURE_USE_TERMIOS
	struct winsize win = { 0, 0, 0, 0 };
#endif

	argc--;
	argv++;


	/* not use inputing from terminal if usage: more > outfile */
	if(isatty(fileno(stdout))) {
		cin = fopen(CURRENT_TTY, "r");
		if (!cin)
			cin = bb_xfopen(CONSOLE_DEV, "r");
		please_display_more_prompt = 0;
#ifdef CONFIG_FEATURE_USE_TERMIOS
		getTermSettings(fileno(cin), &initial_settings);
		new_settings = initial_settings;
		new_settings.c_lflag &= ~ICANON;
		new_settings.c_lflag &= ~ECHO;
#ifndef linux
                /* Hmm, in linux c_cc[] not parsed if set ~ICANON */
		new_settings.c_cc[VMIN] = 1;
		new_settings.c_cc[VTIME] = 0;
#endif
		setTermSettings(fileno(cin), &new_settings);
		atexit(set_tty_to_initial_mode);
		(void) signal(SIGINT, gotsig);
		(void) signal(SIGQUIT, gotsig);
		(void) signal(SIGTERM, gotsig);
#endif
	}

	do {
		if (argc == 0) {
			file = stdin;
		} else
			file = bb_wfopen(*argv, "r");
		if(file==0)
			goto loop;
			
		st.st_size = 0;
		fstat(fileno(file), &st);

		if(please_display_more_prompt>0)
			please_display_more_prompt = 0;

#if defined CONFIG_FEATURE_AUTOWIDTH && defined CONFIG_FEATURE_USE_TERMIOS
		ioctl(fileno(stdout), TIOCGWINSZ, &win);
		if (win.ws_row > 4)
			terminal_height = win.ws_row - 2;
		if (win.ws_col > 0)
			terminal_width = win.ws_col - 1;
#endif
		len=0;
		lines = 0;
		page_height = terminal_height;
		while ((c = getc(file)) != EOF) {

			if (please_display_more_prompt>0) {
				len = printf("--More-- ");
				if (file != stdin && st.st_size > 0) {
#if _FILE_OFFSET_BITS == 64
					len += printf("(%d%% of %lld bytes)",
						   (int) (100 * ((double) ftell(file) /
						   (double) st.st_size)), (long long)st.st_size);
#else
					len += printf("(%d%% of %ld bytes)",
						   (int) (100 * ((double) ftell(file) /
						   (double) st.st_size)), (long)st.st_size);
#endif
				}

				fflush(stdout);

				/*
				 * We've just displayed the "--More--" prompt, so now we need
				 * to get input from the user.
				 */
				input = getc(cin);
#ifndef CONFIG_FEATURE_USE_TERMIOS
				printf("\033[A"); /* up cursor */
#endif
				/* Erase the "More" message */
				putc('\r', stdout);
				while (--len >= 0)
					putc(' ', stdout);
				putc('\r', stdout);
				fflush(stdout);
				len=0;
				lines = 0;
				page_height = terminal_height;
				please_display_more_prompt = 0;

				if (input == 'q')
					goto end;
			}

			/* 
			 * There are two input streams to worry about here:
			 *
			 * c     : the character we are reading from the file being "mored"
			 * input : a character received from the keyboard
			 *
			 * If we hit a newline in the _file_ stream, we want to test and
			 * see if any characters have been hit in the _input_ stream. This
			 * allows the user to quit while in the middle of a file.
			 */
			if (c == '\n') {
				/* increment by just one line if we are at
				 * the end of this line */
				if (input == '\n')
					if(please_display_more_prompt==0)
					please_display_more_prompt = 1;
				/* Adjust the terminal height for any overlap, so that
				 * no lines get lost off the top. */
				if (len >= terminal_width) {
					int quot, rem;
					quot = len / terminal_width;
					rem  = len - (quot * terminal_width);
					if (quot) {
						if (rem)
							page_height-=quot;
						else
							page_height-=(quot-1);
					}
				}
				if (++lines >= page_height) {
					if(please_display_more_prompt==0)
					please_display_more_prompt = 1;
				}
				len=0;
			}
			/*
			 * If we just read a newline from the file being 'mored' and any
			 * key other than a return is hit, scroll by one page
			 */
			putc(c, stdout);
			len++;
		}
		fclose(file);
		fflush(stdout);
loop:
		argv++;
	} while (--argc > 0);
  end:
	return 0;
}