research.m1stereo.tv/gitweb/ - melted/blob - src/mvcp-client/io.c

   1 /*
   2  * io.c -- Valerie client demo input/output
   3  * Copyright (C) 2002-2003 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /* System header files */
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <ctype.h>
  26 #include <termios.h>
  27 #include <unistd.h>
  28 #include <sys/time.h>
  29
  30 /* Application header files */
  31 #include "io.h"
  32
  33 char *chomp( char *input )
  34 {
  35         if ( input != NULL )
  36         {
  37                 int length = strlen( input );
  38                 if ( length && input[ length - 1 ] == '\n' )
  39                         input[ length - 1 ] = '\0';
  40                 if ( length > 1 && input[ length - 2 ] == '\r' )
  41                         input[ length - 2 ] = '\0';
  42         }
  43         return input;
  44 }
  45
  46 char *trim( char *input )
  47 {
  48         if ( input != NULL )
  49         {
  50                 int length = strlen( input );
  51                 int first = 0;
  52                 while( first < length && isspace( input[ first ] ) )
  53                         first ++;
  54                 memmove( input, input + first, length - first + 1 );
  55                 length = length - first;
  56                 while ( length > 0 && isspace( input[ length - 1 ] ) )
  57                         input[ -- length ] = '\0';
  58         }
  59         return input;
  60 }
  61
  62 char *strip_quotes( char *input )
  63 {
  64         if ( input != NULL )
  65         {
  66                 char *ptr = strrchr( input, '\"' );
  67                 if ( ptr != NULL )
  68                         *ptr = '\0';
  69                 if ( input[ 0 ] == '\"' )
  70                         strcpy( input, input + 1 );
  71         }
  72         return input;
  73 }
  74
  75 char *io_get_string( char *output, int maxlength, const char *use )
  76 {
  77         char *value = NULL;
  78         strcpy( output, use );
  79         if ( trim( chomp( fgets( output, maxlength, stdin ) ) ) != NULL )
  80         {
  81                 if ( !strcmp( output, "" ) )
  82                         strcpy( output, use );
  83                 value = output;
  84         }
  85         return value;
  86 }
  87
  88 int *get_int( int *output, int use )
  89 {
  90         int *value = NULL;
  91         char temp[ 132 ];
  92         *output = use;
  93         if ( trim( chomp( fgets( temp, 132, stdin ) ) ) != NULL )
  94         {
  95                 if ( strcmp( temp, "" ) )
  96                         *output = atoi( temp );
  97                 value = output;
  98         }
  99         return value;
 100 }
 101
 102 /** This stores the previous settings
 103 */
 104
 105 static struct termios oldtty;
 106 static int mode = 0;
 107
 108 /** This is called automatically on application exit to restore the
 109         previous tty settings.
 110 */
 111
 112 void term_exit(void)
 113 {
 114         if ( mode == 1 )
 115         {
 116                 tcsetattr( 0, TCSANOW, &oldtty );
 117                 mode = 0;
 118         }
 119 }
 120
 121 /** Init terminal so that we can grab keys without blocking.
 122 */
 123
 124 void term_init( )
 125 {
 126         struct termios tty;
 127
 128         tcgetattr( 0, &tty );
 129         oldtty = tty;
 130
 131         tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
 132         tty.c_oflag |= OPOST;
 133         tty.c_lflag &= ~(ECHO|ECHONL|ICANON|IEXTEN);
 134         tty.c_cflag &= ~(CSIZE|PARENB);
 135         tty.c_cflag |= CS8;
 136         tty.c_cc[ VMIN ] = 1;
 137         tty.c_cc[ VTIME ] = 0;
 138
 139         tcsetattr( 0, TCSANOW, &tty );
 140
 141         mode = 1;
 142
 143         atexit( term_exit );
 144 }
 145
 146 /** Check for a keypress without blocking infinitely.
 147         Returns: ASCII value of keypress or -1 if no keypress detected.
 148 */
 149
 150 int term_read( )
 151 {
 152     int n = 1;
 153     unsigned char ch;
 154     struct timeval tv;
 155     fd_set rfds;
 156
 157     FD_ZERO( &rfds );
 158     FD_SET( 0, &rfds );
 159     tv.tv_sec = 1;
 160     tv.tv_usec = 0;
 161     n = select( 1, &rfds, NULL, NULL, &tv );
 162     if (n > 0)
 163         {
 164         n = read( 0, &ch, 1 );
 165                 tcflush( 0, TCIFLUSH );
 166         if (n == 1)
 167             return ch;
 168         return n;
 169     }
 170     return -1;
 171 }
 172
 173 char get_keypress( )
 174 {
 175         char value = '\0';
 176         int pressed = 0;
 177
 178         fflush( stdout );
 179
 180         term_init( );
 181         while ( ( pressed = term_read( ) ) == -1 ) ;
 182         term_exit( );
 183
 184         value = (char)pressed;
 185
 186         return value;
 187 }
 188
 189 void wait_for_any_key( const char *message )
 190 {
 191         if ( message == NULL )
 192                 printf( "Press any key to continue: " );
 193         else
 194                 printf( "%s", message );
 195
 196         get_keypress( );
 197
 198         printf( "\n\n" );
 199 }
 200
 201 void beep( )
 202 {
 203         printf( "%c", 7 );
 204         fflush( stdout );
 205 }