/* * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ FILE_LICENCE ( GPL2_OR_LATER ); #include <stdio.h> #include <string.h> #include <stdlib.h> #include <console.h> #include <gpxe/keys.h> #include <gpxe/editstring.h> #include <readline/readline.h> /** @file * * Minimal readline * */ #define READLINE_MAX 256 static void sync_console ( struct edit_string *string ) __nonnull; /** * Synchronise console with edited string * * @v string Editable string */ static void sync_console ( struct edit_string *string ) { unsigned int mod_start = string->mod_start; unsigned int mod_end = string->mod_end; unsigned int cursor = string->last_cursor; size_t len = strlen ( string->buf ); /* Expand region back to old cursor position if applicable */ if ( mod_start > string->last_cursor ) mod_start = string->last_cursor; /* Expand region forward to new cursor position if applicable */ if ( mod_end < string->cursor ) mod_end = string->cursor; /* Backspace to start of region */ while ( cursor > mod_start ) { putchar ( '\b' ); cursor--; } /* Print modified region */ while ( cursor < mod_end ) { putchar ( ( cursor >= len ) ? ' ' : string->buf[cursor] ); cursor++; } /* Backspace to new cursor position */ while ( cursor > string->cursor ) { putchar ( '\b' ); cursor--; } } /** * Read line from console * * @v prompt Prompt string * @ret line Line read from console (excluding terminating newline) * * The returned line is allocated with malloc(); the caller must * eventually call free() to release the storage. */ char * readline ( const char *prompt ) { char buf[READLINE_MAX]; struct edit_string string; int key; char *line; if ( prompt ) printf ( "%s", prompt ); memset ( &string, 0, sizeof ( string ) ); string.buf = buf; string.len = sizeof ( buf ); buf[0] = '\0'; while ( 1 ) { key = edit_string ( &string, getkey() ); sync_console ( &string ); switch ( key ) { case CR: case LF: putchar ( '\n' ); line = strdup ( buf ); if ( ! line ) printf ( "Out of memory\n" ); return line; case CTRL_C: putchar ( '\n' ); return NULL; default: /* Do nothing */ break; } } }