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 <stdio.h>
  29 #include <fcntl.h>
  30 #include <signal.h>
  31 #include <stdlib.h>
  32 #include <sys/ioctl.h>
  33 #include "busybox.h"
  34 #define BB_DECLARE_EXTERN
  35 #define bb_need_help
  36 #include "messages.c"
  37
  38 /* ED: sparc termios is broken: revert back to old termio handling. */
  39 #ifdef BB_FEATURE_USE_TERMIOS
  40 #       if #cpu(sparc)
  41 #               include <termio.h>
  42 #               define termios termio
  43 #               define setTermSettings(fd,argp) ioctl(fd,TCSETAF,argp)
  44 #               define getTermSettings(fd,argp) ioctl(fd,TCGETA,argp)
  45 #       else
  46 #               include <termios.h>
  47 #               define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
  48 #               define getTermSettings(fd,argp) tcgetattr(fd, argp);
  49 #       endif
  50
  51 static FILE *cin;
  52
  53 static struct termios initial_settings, new_settings;
  54
  55 static void gotsig(int sig)
  56 {
  57         setTermSettings(fileno(cin), &initial_settings);
  58         putchar('\n');
  59         exit(EXIT_FAILURE);
  60 }
  61 #endif /* BB_FEATURE_USE_TERMIOS */
  62
  63
  64 static int terminal_width = 79; /* not 80 in case terminal has linefold bug */
  65 static int terminal_height = 24;
  66
  67
  68 extern int more_main(int argc, char **argv)
  69 {
  70         int c, lines, input = 0;
  71         int please_display_more_prompt;
  72         struct stat st;
  73         FILE *file;
  74         int len, page_height;
  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                 len=0;
 117                 lines = 0;
 118                 page_height = terminal_height;
 119                 please_display_more_prompt = 0;
 120                 while ((c = getc(file)) != EOF) {
 121
 122                         if (please_display_more_prompt) {
 123                                 len = printf("--More-- ");
 124                                 if (file != stdin) {
 125 #if _FILE_OFFSET_BITS == 64
 126                                         len += printf("(%d%% of %lld bytes)",
 127 #else
 128                                         len += printf("(%d%% of %ld bytes)",
 129 #endif
 130                                                                    (int) (100 *
 131                                                                                   ((double) ftell(file) /
 132                                                                                    (double) st.st_size)),
 133                                                                    st.st_size);
 134                                 }
 135                                 len += printf("%s",
 136 #ifdef BB_FEATURE_USE_TERMIOS
 137                                                            ""
 138 #else
 139                                                            "\n"
 140 #endif
 141                                         );
 142
 143                                 fflush(stdout);
 144
 145                                 /*
 146                                  * We've just displayed the "--More--" prompt, so now we need
 147                                  * to get input from the user.
 148                                  */
 149 #ifdef BB_FEATURE_USE_TERMIOS
 150                                 input = getc(cin);
 151 #else
 152                                 input = getc(stdin);
 153 #endif
 154
 155 #ifdef BB_FEATURE_USE_TERMIOS
 156                                 /* Erase the "More" message */
 157                                 while (--len >= 0)
 158                                         putc('\b', stdout);
 159                                 while (++len <= terminal_width)
 160                                         putc(' ', stdout);
 161                                 while (--len >= 0)
 162                                         putc('\b', stdout);
 163                                 fflush(stdout);
 164 #endif
 165                                 len=0;
 166                                 lines = 0;
 167                                 page_height = terminal_height;
 168                                 please_display_more_prompt = 0;
 169                         }
 170
 171                         /*
 172                          * There are two input streams to worry about here:
 173                          *
 174                          * c     : the character we are reading from the file being "mored"
 175                          * input : a character received from the keyboard
 176                          *
 177                          * If we hit a newline in the _file_ stream, we want to test and
 178                          * see if any characters have been hit in the _input_ stream. This
 179                          * allows the user to quit while in the middle of a file.
 180                          */
 181                         if (c == '\n') {
 182                                 switch (input) {
 183                                 case 'q':
 184                                         goto end;
 185                                 case '\n':
 186                                         /* increment by just one line if we are at
 187                                          * the end of this line*/
 188                                         please_display_more_prompt = 1;
 189                                         break;
 190                                 }
 191                                 /* Adjust the terminal height for any overlap, so that
 192                                  * no lines get lost off the top. */
 193                                 if (len >= terminal_width) {
 194                                         div_t result = div( len, terminal_width);
 195                                         if (result.quot) {
 196                                                 if (result.rem)
 197                                                         page_height-=result.quot;
 198                                                 else
 199                                                         page_height-=(result.quot-1);
 200                                         }
 201                                 }
 202                                 if (++lines >= page_height) {
 203                                         please_display_more_prompt = 1;
 204                                 }
 205                                 len=0;
 206                         }
 207                         /*
 208                          * If we just read a newline from the file being 'mored' and any
 209                          * key other than a return is hit, scroll by one page
 210                          */
 211                         putc(c, stdout);
 212                         len++;
 213                 }
 214                 fclose(file);
 215                 fflush(stdout);
 216
 217                 argv++;
 218         } while (--argc > 0);
 219   end:
 220 #ifdef BB_FEATURE_USE_TERMIOS
 221         gotsig(0);
 222 #endif
 223         return(TRUE);
 224 }