15c3b6f87db377ee58b4d9a6dcf8f14d22d334b8
[oweals/busybox.git] / util-linux / more.c
1 #error Foo
2 /* vi: set sw=4 ts=4: */
3 /*
4  * Mini more implementation for busybox
5  *
6  *
7  * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
8  *
9  * Latest version blended together by Erik Andersen <andersen@lineo.com>,
10  * based on the original more implementation by Bruce, and code from the 
11  * Debian boot-floppies team.
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26  *
27  */
28
29 #include "busybox.h"
30 #include <stdio.h>
31 #include <fcntl.h>
32 #include <signal.h>
33 #include <stdlib.h>
34 #include <sys/ioctl.h>
35 #define BB_DECLARE_EXTERN
36 #define bb_need_help
37 #include "messages.c"
38
39 /* ED: sparc termios is broken: revert back to old termio handling. */
40 #ifdef BB_FEATURE_USE_TERMIOS
41 #       if #cpu(sparc)
42 #               include <termio.h>
43 #               define termios termio
44 #               define setTermSettings(fd,argp) ioctl(fd,TCSETAF,argp)
45 #               define getTermSettings(fd,argp) ioctl(fd,TCGETA,argp)
46 #       else
47 #               include <termios.h>
48 #               define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
49 #               define getTermSettings(fd,argp) tcgetattr(fd, argp);
50 #       endif
51
52 static FILE *cin;
53
54 static struct termios initial_settings, new_settings;
55
56 static void gotsig(int sig)
57 {
58         setTermSettings(fileno(cin), &initial_settings);
59         putchar('\n');
60         exit(EXIT_FAILURE);
61 }
62 #endif /* BB_FEATURE_USE_TERMIOS */
63
64
65 static int terminal_width = 79; /* not 80 in case terminal has linefold bug */
66 static int terminal_height = 24;
67
68
69 extern int more_main(int argc, char **argv)
70 {
71         int c, lines = 0, input = 0;
72         int please_display_more_prompt = 0;
73         struct stat st;
74         FILE *file;
75
76 #if defined BB_FEATURE_AUTOWIDTH && defined BB_FEATURE_USE_TERMIOS
77         struct winsize win = { 0, 0, 0, 0 };
78 #endif
79
80         argc--;
81         argv++;
82
83         do {
84                 if (argc == 0) {
85                         file = stdin;
86                 } else
87                         file = xfopen(*argv, "r");
88
89                 fstat(fileno(file), &st);
90
91 #ifdef BB_FEATURE_USE_TERMIOS
92                 cin = fopen("/dev/tty", "r");
93                 if (!cin)
94                         cin = fopen("/dev/console", "r");
95                 getTermSettings(fileno(cin), &initial_settings);
96                 new_settings = initial_settings;
97                 new_settings.c_cc[VMIN] = 1;
98                 new_settings.c_cc[VTIME] = 0;
99                 new_settings.c_lflag &= ~ICANON;
100                 new_settings.c_lflag &= ~ECHO;
101                 setTermSettings(fileno(cin), &new_settings);
102
103 #       ifdef BB_FEATURE_AUTOWIDTH
104                 ioctl(fileno(stdout), TIOCGWINSZ, &win);
105                 if (win.ws_row > 4)
106                         terminal_height = win.ws_row - 2;
107                 if (win.ws_col > 0)
108                         terminal_width = win.ws_col - 1;
109 #       endif
110
111                 (void) signal(SIGINT, gotsig);
112                 (void) signal(SIGQUIT, gotsig);
113                 (void) signal(SIGTERM, gotsig);
114
115 #endif
116                 while ((c = getc(file)) != EOF) {
117                         if (please_display_more_prompt) {
118                                 int len = 0;
119
120                                 please_display_more_prompt = 0;
121                                 lines = 0;
122                                 len = printf("--More-- ");
123                                 if (file != stdin) {
124 #if _FILE_OFFSET_BITS == 64
125                                         len += printf("(%d%% of %lld bytes)",
126 #else
127                                         len += printf("(%d%% of %ld bytes)",
128 #endif
129                                                                    (int) (100 *
130                                                                                   ((double) ftell(file) /
131                                                                                    (double) st.st_size)),
132                                                                    st.st_size);
133                                 }
134                                 len += printf("%s",
135 #ifdef BB_FEATURE_USE_TERMIOS
136                                                            ""
137 #else
138                                                            "\n"
139 #endif
140                                         );
141
142                                 fflush(stdout);
143
144                                 /*
145                                  * We've just displayed the "--More--" prompt, so now we need
146                                  * to get input from the user.
147                                  */
148 #ifdef BB_FEATURE_USE_TERMIOS
149                                 input = getc(cin);
150 #else
151                                 input = getc(stdin);
152 #endif
153
154 #ifdef BB_FEATURE_USE_TERMIOS
155                                 /* Erase the "More" message */
156                                 while (--len >= 0)
157                                         putc('\b', stdout);
158                                 while (++len <= terminal_width)
159                                         putc(' ', stdout);
160                                 while (--len >= 0)
161                                         putc('\b', stdout);
162                                 fflush(stdout);
163 #endif
164
165                         }
166
167                         /* 
168                          * There are two input streams to worry about here:
169                          *
170                          *     c : the character we are reading from the file being "mored"
171                          * input : a character received from the keyboard
172                          *
173                          * If we hit a newline in the _file_ stream, we want to test and
174                          * see if any characters have been hit in the _input_ stream. This
175                          * allows the user to quit while in the middle of a file.
176                          */
177                         if (c == '\n') {
178                                 switch (input) {
179                                 case 'q':
180                                         goto end;
181                                 case '\n':
182                                         /* increment by just one line if we are at 
183                                          * the end of this line*/
184                                         please_display_more_prompt = 1;
185                                         break;
186                                 }
187                                 if (++lines == terminal_height)
188                                         please_display_more_prompt = 1;
189                         }
190                         /*
191                          * If we just read a newline from the file being 'mored' and any
192                          * key other than a return is hit, scroll by one page
193                          */
194                         putc(c, stdout);
195                 }
196                 fclose(file);
197                 fflush(stdout);
198
199                 argv++;
200         } while (--argc > 0);
201   end:
202 #ifdef BB_FEATURE_USE_TERMIOS
203         gotsig(0);
204 #endif
205         return(TRUE);
206 }