// fake_serial.cc // nono - programme du robot 2004. {{{ // // Copyright (C) 2004 Nicolas Schodet // // Robot APB Team/Efrei 2004. // Web: http://assos.efrei.fr/robot/ // Email: robot AT efrei DOT fr // // 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 // (at your option) 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. // // }}} #include "fake_serial.h" #include "utils/rand.h" /// Constructeur. FakeSerial::FakeSerial (bool blocking/*false*/) : blocking_ (blocking), lostP_ (1000), errorP_ (1000) { } /// Lit un bloc, retourne le nombre d'octets lus ou <= 0 en cas d'erreur /// ou si aucun caractère n'est disponible. Pour le robot, préferer en /// général getchar() pour du non-bloquant. ssize_t FakeSerial::read (void *buf, size_t size) { char p[size]; int ret; do { ret = ::read (0, p, size); if (ret > 0) { char *po = reinterpret_cast (buf); int n = 0; for (int i = 0; i < ret; ++i) { if (!(rand () % lostP_)) { // Saute le caractère. } else { po[n++] = doError (p[i]); } } ret = n; } else return ret; } while (ret <= 0 && blocking_); return ret; } /// Lit un caractère, ou -1 en cas d'erreur ou si aucun caractère n'est /// disponible. int FakeSerial::getchar (void) { char c; return read (&c, 1) > 0 ? c : -1; } /// Ecrit un bloc. void FakeSerial::write (const void *buf, size_t size) { const unsigned char *p = reinterpret_cast (buf); size_t i; char c; for (i = 0; i < size; ++i) { if (!(rand () % lostP_)) continue; c = doError (p[i]); ::write (1, &c, 1); } } /// Ecrit un caractère. void FakeSerial::putchar (int c) { write (&c, 1); } /// Inverse peut-être un bit aléatoirement. char FakeSerial::doError (char c) { if (!(rand () % errorP_)) return c ^ (1 << (rand () % 8)); else return c; }