| Greg Hartman | 76d05dc | 2016-11-23 15:51:27 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License as |
| 6 | * published by the Free Software Foundation; either version 2 of the |
| 7 | * License, or any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 17 | */ |
| 18 | |
| 19 | FILE_LICENCE ( GPL2_OR_LATER ); |
| 20 | |
| 21 | #include <ctype.h> |
| 22 | #include <console.h> |
| 23 | #include <gpxe/process.h> |
| 24 | #include <gpxe/keys.h> |
| 25 | #include <gpxe/timer.h> |
| 26 | |
| 27 | /** @file |
| 28 | * |
| 29 | * Special key interpretation |
| 30 | * |
| 31 | */ |
| 32 | |
| 33 | #define GETKEY_TIMEOUT ( TICKS_PER_SEC / 4 ) |
| 34 | |
| 35 | /** |
| 36 | * Read character from console if available within timeout period |
| 37 | * |
| 38 | * @v timeout Timeout period, in ticks |
| 39 | * @ret character Character read from console |
| 40 | */ |
| 41 | static int getchar_timeout ( unsigned long timeout ) { |
| 42 | unsigned long expiry = ( currticks() + timeout ); |
| 43 | |
| 44 | while ( currticks() < expiry ) { |
| 45 | step(); |
| 46 | if ( iskey() ) |
| 47 | return getchar(); |
| 48 | } |
| 49 | |
| 50 | return -1; |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * Get single keypress |
| 55 | * |
| 56 | * @ret key Key pressed |
| 57 | * |
| 58 | * The returned key will be an ASCII value or a KEY_XXX special |
| 59 | * constant. This function differs from getchar() in that getchar() |
| 60 | * will return "special" keys (e.g. cursor keys) as a series of |
| 61 | * characters forming an ANSI escape sequence. |
| 62 | */ |
| 63 | int getkey ( void ) { |
| 64 | int character; |
| 65 | unsigned int n = 0; |
| 66 | |
| 67 | character = getchar(); |
| 68 | if ( character != ESC ) |
| 69 | return character; |
| 70 | |
| 71 | while ( ( character = getchar_timeout ( GETKEY_TIMEOUT ) ) >= 0 ) { |
| 72 | if ( character == '[' ) |
| 73 | continue; |
| 74 | if ( isdigit ( character ) ) { |
| 75 | n = ( ( n * 10 ) + ( character - '0' ) ); |
| 76 | continue; |
| 77 | } |
| 78 | if ( character >= 0x40 ) |
| 79 | return KEY_ANSI ( n, character ); |
| 80 | } |
| 81 | |
| 82 | return ESC; |
| 83 | } |