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 #define BB_DECLARE_EXTERN
  34 #define bb_need_help
  35 #include "messages.c"
  36
  37 /* ED: sparc termios is broken: revert back to old termio handling. */
  38 #ifdef BB_FEATURE_USE_TERMIOS
  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
  52 struct termios initial_settings, new_settings;
  53
  54 void gotsig(int sig)
  55 {
  56         setTermSettings(fileno(cin), &initial_settings);
  57         fprintf(stdout, "\n");
  58         exit(TRUE);
  59 }
  60 #endif /* BB_FEATURE_USE_TERMIOS */
  61
  62
  63 static int terminal_width = 79; /* not 80 in case terminal has linefold bug */
  64 static int terminal_height = 24;
  65
  66
  67 extern int more_main(int argc, char **argv)
  68 {
  69         int c, lines = 0, input = 0;
  70         int please_display_more_prompt = 0;
  71         struct stat st;
  72         FILE *file;
  73
  74 #if defined BB_FEATURE_AUTOWIDTH && defined BB_FEATURE_USE_TERMIOS
  75         struct winsize win = { 0, 0, 0, 0 };
  76 #endif
  77
  78         argc--;
  79         argv++;
  80
  81         do {
  82                 if (argc == 0) {
  83                         file = stdin;
  84                 } else
  85                         file = fopen(*argv, "r");
  86
  87                 if (file == NULL) {
  88                         perror(*argv);
  89                         exit(FALSE);
  90                 }
  91                 fstat(fileno(file), &st);
  92
  93 #ifdef BB_FEATURE_USE_TERMIOS
  94                 cin = fopen("/dev/tty", "r");
  95                 if (!cin)
  96                         cin = fopen("/dev/console", "r");
  97                 getTermSettings(fileno(cin), &initial_settings);
  98                 new_settings = initial_settings;
  99                 new_settings.c_cc[VMIN] = 1;
 100                 new_settings.c_cc[VTIME] = 0;
 101                 new_settings.c_lflag &= ~ICANON;
 102                 new_settings.c_lflag &= ~ECHO;
 103                 setTermSettings(fileno(cin), &new_settings);
 104
 105 #       ifdef BB_FEATURE_AUTOWIDTH
 106                 ioctl(fileno(stdout), TIOCGWINSZ, &win);
 107                 if (win.ws_row > 4)
 108                         terminal_height = win.ws_row - 2;
 109                 if (win.ws_col > 0)
 110                         terminal_width = win.ws_col - 1;
 111 #       endif
 112
 113                 (void) signal(SIGINT, gotsig);
 114                 (void) signal(SIGQUIT, gotsig);
 115                 (void) signal(SIGTERM, gotsig);
 116
 117 #endif
 118                 while ((c = getc(file)) != EOF) {
 119                         if (please_display_more_prompt) {
 120                                 int len = 0;
 121
 122                                 please_display_more_prompt = 0;
 123                                 lines = 0;
 124                                 len = fprintf(stdout, "--More-- ");
 125                                 if (file != stdin) {
 126                                         len += fprintf(stdout, "(%d%% of %ld bytes)",
 127                                                                    (int) (100 *
 128                                                                                   ((double) ftell(file) /
 129                                                                                    (double) st.st_size)),
 130                                                                    st.st_size);
 131                                 }
 132                                 len += fprintf(stdout, "%s",
 133 #ifdef BB_FEATURE_USE_TERMIOS
 134                                                            ""
 135 #else
 136                                                            "\n"
 137 #endif
 138                                         );
 139
 140                                 fflush(stdout);
 141
 142                                 /*
 143                                  * We've just displayed the "--More--" prompt, so now we need
 144                                  * to get input from the user.
 145                                  */
 146 #ifdef BB_FEATURE_USE_TERMIOS
 147                                 input = getc(cin);
 148 #else
 149                                 input = getc(stdin);
 150 #endif
 151
 152 #ifdef BB_FEATURE_USE_TERMIOS
 153                                 /* Erase the "More" message */
 154                                 while (--len >= 0)
 155                                         putc('\b', stdout);
 156                                 while (++len <= terminal_width)
 157                                         putc(' ', stdout);
 158                                 while (--len >= 0)
 159                                         putc('\b', stdout);
 160                                 fflush(stdout);
 161 #endif
 162
 163                         }
 164
 165                         /*
 166                          * There are two input streams to worry about here:
 167                          *
 168                          *     c : the character we are reading from the file being "mored"
 169                          * input : a character received from the keyboard
 170                          *
 171                          * If we hit a newline in the _file_ stream, we want to test and
 172                          * see if any characters have been hit in the _input_ stream. This
 173                          * allows the user to quit while in the middle of a file.
 174                          */
 175                         if (c == '\n') {
 176                                 switch (input) {
 177                                 case 'q':
 178                                         goto end;
 179                                 case '\n':
 180                                         /* increment by just one line if we are at
 181                                          * the end of this line*/
 182                                         please_display_more_prompt = 1;
 183                                         break;
 184                                 }
 185                                 if (++lines == terminal_height)
 186                                         please_display_more_prompt = 1;
 187                         }
 188                         /*
 189                          * If we just read a newline from the file being 'mored' and any
 190                          * key other than a return is hit, scroll by one page
 191                          */
 192                         putc(c, stdout);
 193                 }
 194                 fclose(file);
 195                 fflush(stdout);
 196
 197                 argv++;
 198         } while (--argc > 0);
 199   end:
 200 #ifdef BB_FEATURE_USE_TERMIOS
 201         gotsig(0);
 202 #endif
 203         return(TRUE);
 204 }