util-linux/more.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini more implementation for busybox
   4  *
   5  *
   6  * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
   7  *
   8  * Latest version blended together by Erik Andersen <andersen@lineo.com>,
   9  * based on the original more implementation by Bruce, and code from the
  10  * Debian boot-floppies team.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  *
  26  */
  27
  28 #include "internal.h"
  29 #include <stdio.h>
  30 #include <fcntl.h>
  31 #include <signal.h>
  32 #include <sys/ioctl.h>
  33
  34 static const char more_usage[] = "more [file ...]\n";
  35
  36 /* ED: sparc termios is broken: revert back to old termio handling. */
  37 #ifdef BB_FEATURE_USE_TERMIOS
  38
  39 #if #cpu(sparc)
  40 #      include <termio.h>
  41 #      define termios termio
  42 #      define setTermSettings(fd,argp) ioctl(fd,TCSETAF,argp)
  43 #      define getTermSettings(fd,argp) ioctl(fd,TCGETA,argp)
  44 #else
  45 #      include <termios.h>
  46 #      define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
  47 #      define getTermSettings(fd,argp) tcgetattr(fd, argp);
  48 #endif
  49
  50 FILE *cin;
  51 struct termios initial_settings, new_settings;
  52
  53 void gotsig(int sig)
  54 {
  55         setTermSettings(fileno(cin), &initial_settings);
  56         fprintf(stdout, "\n");
  57         exit(TRUE);
  58 }
  59 #endif
  60
  61
  62
  63 #define TERMINAL_WIDTH  79              /* not 80 in case terminal has linefold bug */
  64 #define TERMINAL_HEIGHT 24
  65
  66
  67 #if defined BB_FEATURE_AUTOWIDTH
  68 static int terminal_width = 0, terminal_height = 0;
  69 #else
  70 #define terminal_width  TERMINAL_WIDTH
  71 #define terminal_height TERMINAL_HEIGHT
  72 #endif
  73
  74
  75
  76 extern int more_main(int argc, char **argv)
  77 {
  78         int c, lines = 0, input = 0;
  79         int next_page = 0;
  80         struct stat st;
  81         FILE *file;
  82
  83 #ifdef BB_FEATURE_AUTOWIDTH
  84         struct winsize win = { 0, 0 };
  85 #endif
  86
  87         argc--;
  88         argv++;
  89
  90         if (argc > 0
  91                 && (strcmp(*argv, "--help") == 0 || strcmp(*argv, "-h") == 0)) {
  92                 usage(more_usage);
  93         }
  94         do {
  95                 if (argc == 0) {
  96                         file = stdin;
  97                 } else
  98                         file = fopen(*argv, "r");
  99
 100                 if (file == NULL) {
 101                         perror(*argv);
 102                         exit(FALSE);
 103                 }
 104                 fstat(fileno(file), &st);
 105
 106 #ifdef BB_FEATURE_USE_TERMIOS
 107                 cin = fopen("/dev/tty", "r");
 108                 if (!cin)
 109                         cin = fopen("/dev/console", "r");
 110                 getTermSettings(fileno(cin), &initial_settings);
 111                 new_settings = initial_settings;
 112                 new_settings.c_lflag &= ~ICANON;
 113                 new_settings.c_lflag &= ~ECHO;
 114                 setTermSettings(fileno(cin), &new_settings);
 115
 116 #ifdef BB_FEATURE_AUTOWIDTH
 117                 ioctl(fileno(stdout), TIOCGWINSZ, &win);
 118                 if (win.ws_row > 4)
 119                         terminal_height = win.ws_row - 2;
 120                 if (win.ws_col > 0)
 121                         terminal_width = win.ws_col - 1;
 122 #endif
 123
 124                 (void) signal(SIGINT, gotsig);
 125                 (void) signal(SIGQUIT, gotsig);
 126                 (void) signal(SIGTERM, gotsig);
 127
 128 #endif
 129                 while ((c = getc(file)) != EOF) {
 130                         if (next_page) {
 131                                 int len = 0;
 132
 133                                 next_page = 0;
 134                                 lines = 0;
 135                                 len = fprintf(stdout, "--More-- ");
 136                                 if (file != stdin) {
 137                                         len += fprintf(stdout, "(%d%% of %ld bytes)",
 138                                                                    (int) (100 *
 139                                                                                   ((double) ftell(file) /
 140                                                                                    (double) st.st_size)),
 141                                                                    st.st_size);
 142                                 }
 143                                 len += fprintf(stdout, "%s",
 144 #ifdef BB_FEATURE_USE_TERMIOS
 145                                                            ""
 146 #else
 147                                                            "\n"
 148 #endif
 149                                         );
 150
 151                                 fflush(stdout);
 152                                 input = getc(cin);
 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                         if (c == '\n') {
 167                                 switch (input) {
 168                                 case 'q':
 169                                         goto end;
 170                                 case '\n':
 171                                         /* increment by just one line if we are at
 172                                          * the end of this line*/
 173                                         next_page = 1;
 174                                         break;
 175                                 }
 176                                 if (++lines == terminal_height)
 177                                         next_page = 1;
 178                         }
 179                         putc(c, stdout);
 180                 }
 181                 fclose(file);
 182                 fflush(stdout);
 183
 184                 argv++;
 185         } while (--argc > 0);
 186   end:
 187 #ifdef BB_FEATURE_USE_TERMIOS
 188         gotsig(0);
 189 #endif
 190         exit(TRUE);
 191 }