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 #      define USE_OLD_TERMIO
  41 #      include <termio.h>
  42 #      define termios termio
  43 #      define stty(fd,argp) ioctl(fd,TCSETAF,argp)
  44 #else
  45 #      include <termios.h>
  46 #      define stty(fd,argp) tcsetattr(fd,TCSANOW,argp)
  47 #endif
  48
  49 FILE *cin;
  50 struct termios initial_settings, new_settings;
  51
  52 void gotsig(int sig)
  53 {
  54         stty(fileno(cin), &initial_settings);
  55         fprintf(stdout, "\n");
  56         exit(TRUE);
  57 }
  58 #endif
  59
  60
  61
  62 #define TERMINAL_WIDTH  79              /* not 80 in case terminal has linefold bug */
  63 #define TERMINAL_HEIGHT 24
  64
  65
  66 #if defined BB_FEATURE_AUTOWIDTH
  67 static int terminal_width = 0, terminal_height = 0;
  68 #else
  69 #define terminal_width  TERMINAL_WIDTH
  70 #define terminal_height TERMINAL_HEIGHT
  71 #endif
  72
  73
  74
  75 extern int more_main(int argc, char **argv)
  76 {
  77         int c, lines = 0, input = 0;
  78         int next_page = 0;
  79         struct stat st;
  80         FILE *file;
  81
  82 #ifdef BB_FEATURE_AUTOWIDTH
  83         struct winsize win = { 0, 0 };
  84 #endif
  85
  86         argc--;
  87         argv++;
  88
  89         if (argc > 0
  90                 && (strcmp(*argv, "--help") == 0 || strcmp(*argv, "-h") == 0)) {
  91                 usage(more_usage);
  92         }
  93         do {
  94                 if (argc == 0) {
  95                         file = stdin;
  96                 } else
  97                         file = fopen(*argv, "r");
  98
  99                 if (file == NULL) {
 100                         perror(*argv);
 101                         exit(FALSE);
 102                 }
 103                 fstat(fileno(file), &st);
 104
 105 #ifdef BB_FEATURE_USE_TERMIOS
 106                 cin = fopen("/dev/tty", "r");
 107                 if (!cin)
 108                         cin = fopen("/dev/console", "r");
 109 #ifdef USE_OLD_TERMIO
 110                 ioctl(fileno(cin), TCGETA, &initial_settings);
 111 #else
 112                 tcgetattr(fileno(cin), &initial_settings);
 113 #endif
 114                 new_settings = initial_settings;
 115                 new_settings.c_lflag &= ~ICANON;
 116                 new_settings.c_lflag &= ~ECHO;
 117                 stty(fileno(cin), &new_settings);
 118
 119 #ifdef BB_FEATURE_AUTOWIDTH
 120                 ioctl(fileno(stdout), TIOCGWINSZ, &win);
 121                 if (win.ws_row > 4)
 122                         terminal_height = win.ws_row - 2;
 123                 if (win.ws_col > 0)
 124                         terminal_width = win.ws_col - 1;
 125 #endif
 126
 127                 (void) signal(SIGINT, gotsig);
 128                 (void) signal(SIGQUIT, gotsig);
 129                 (void) signal(SIGTERM, gotsig);
 130
 131 #endif
 132                 while ((c = getc(file)) != EOF) {
 133                         if (next_page) {
 134                                 int len = 0;
 135
 136                                 next_page = 0;
 137                                 lines = 0;
 138                                 len = fprintf(stdout, "--More-- ");
 139                                 if (file != stdin) {
 140                                         len += fprintf(stdout, "(%d%% of %ld bytes)",
 141                                                                    (int) (100 *
 142                                                                                   ((double) ftell(file) /
 143                                                                                    (double) st.st_size)),
 144                                                                    st.st_size);
 145                                 }
 146                                 len += fprintf(stdout, "%s",
 147 #ifdef BB_FEATURE_USE_TERMIOS
 148                                                            ""
 149 #else
 150                                                            "\n"
 151 #endif
 152                                         );
 153
 154                                 fflush(stdout);
 155                                 input = getc(cin);
 156
 157 #ifdef BB_FEATURE_USE_TERMIOS
 158                                 /* Erase the "More" message */
 159                                 while (--len >= 0)
 160                                         putc('\b', stdout);
 161                                 while (++len <= terminal_width)
 162                                         putc(' ', stdout);
 163                                 while (--len >= 0)
 164                                         putc('\b', stdout);
 165                                 fflush(stdout);
 166 #endif
 167
 168                         }
 169                         if (c == '\n') {
 170                                 switch (input) {
 171                                 case 'q':
 172                                         goto end;
 173                                 case '\n':
 174                                         /* increment by just one line if we are at
 175                                          * the end of this line*/
 176                                         next_page = 1;
 177                                         break;
 178                                 }
 179                                 if (++lines == terminal_height)
 180                                         next_page = 1;
 181                         }
 182                         putc(c, stdout);
 183                 }
 184                 fclose(file);
 185                 fflush(stdout);
 186
 187                 argv++;
 188         } while (--argc > 0);
 189   end:
 190 #ifdef BB_FEATURE_USE_TERMIOS
 191         gotsig(0);
 192 #endif
 193         exit(TRUE);
 194 }