Main Page Main Page Related Pages Files sig.cGo to the documentation of this file.00001 /* 00002 * $Id: sig.c,v 1.6 2003/12/01 09:10:16 troth Exp $ 00003 * 00004 **************************************************************************** 00005 * 00006 * simulavr - A simulator for the Atmel AVR family of microcontrollers. 00007 * Copyright (C) 2001, 2002, 2003 Theodore A. Roth 00008 * 00009 * This program is free software; you can redistribute it and/or modify 00010 * it under the terms of the GNU General Public License as published by 00011 * the Free Software Foundation; either version 2 of the License, or 00012 * (at your option) any later version. 00013 * 00014 * This program is distributed in the hope that it will be useful, 00015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00017 * GNU General Public License for more details. 00018 * 00019 * You should have received a copy of the GNU General Public License 00020 * along with this program; if not, write to the Free Software 00021 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 00022 * 00023 **************************************************************************** 00024 */ 00025 00026 /** 00027 * \file sig.c 00028 * \brief Public interface to signal handlers. 00029 * 00030 * This module provides a way for the simulator to process signals generated 00031 * by the native host system. Note that these signals in this context have 00032 * nothing to do with signals or interrupts as far as a program running in the 00033 * simulator is concerned. */ 00034 00035 #include <config.h> 00036 00037 #include <stdio.h> 00038 #include <stdlib.h> 00039 #include <string.h> 00040 #include <errno.h> 00041 #include <signal.h> 00042 00043 #include "avrerror.h" 00044 #include "sig.h" 00045 00046 static volatile int global_got_sigint = 0; 00047 00048 /* 00049 * Private. 00050 * 00051 * Handler for SIGINT signals. 00052 */ 00053 static void 00054 signal_handle_sigint (int signo) 00055 { 00056 global_got_sigint = 1; 00057 } 00058 00059 /** 00060 * \brief Start watching for the occurrance of the given signal. 00061 * 00062 * This function will install a signal handler which will set a flag when the 00063 * signal occurs. Once the watch has been started, periodically call 00064 * signal_has_occurred() to check if the signal was raised. 00065 */ 00066 void 00067 signal_watch_start (int signo) 00068 { 00069 struct sigaction act, oact; 00070 00071 sigemptyset (&act.sa_mask); 00072 act.sa_flags = 0; 00073 00074 switch (signo) 00075 { 00076 case SIGINT: 00077 global_got_sigint = 0; 00078 act.sa_handler = signal_handle_sigint; 00079 break; 00080 default: 00081 avr_warning ("Invalid signal: %d\n", signo); 00082 return; 00083 } 00084 00085 if (sigaction (signo, &act, &oact) < 0) 00086 avr_warning ("Failed to install signal handler: sig=%d: %s\n", signo, 00087 strerror (errno)); 00088 } 00089 00090 /** 00091 * \brief Stop watching signal. 00092 * 00093 * Restores the default signal handler for the given signal and resets the 00094 * signal flag. 00095 */ 00096 void 00097 signal_watch_stop (int signo) 00098 { 00099 struct sigaction act, oact; 00100 00101 sigemptyset (&act.sa_mask); 00102 act.sa_flags = 0; 00103 act.sa_handler = SIG_DFL; 00104 00105 signal_reset (signo); 00106 00107 if (sigaction (signo, &act, &oact) < 0) 00108 avr_warning ("Failed to restore default signal handler: sig=%d: %s\n", 00109 signo, strerror (errno)); 00110 } 00111 00112 /** 00113 * \brief Check to see if a signal has occurred. 00114 * 00115 * \return Non-zero if signal has occurred. The flag will always be reset 00116 * automatically. 00117 */ 00118 int 00119 signal_has_occurred (int signo) 00120 { 00121 int res = 0; 00122 00123 switch (signo) 00124 { 00125 case SIGINT: 00126 res = global_got_sigint; 00127 global_got_sigint = 0; 00128 break; 00129 default: 00130 avr_warning ("Invalid signal: %d", signo); 00131 } 00132 00133 return res; 00134 } 00135 00136 /** 00137 * \brief Clear the flag which indicates that a signal has ocurred. 00138 * 00139 * Use signal_reset to manually reset (i.e. clear) the flag. 00140 */ 00141 void 00142 signal_reset (int signo) 00143 { 00144 signal_has_occurred (signo); 00145 } Automatically generated by Doxygen 1.5.5 on 7 Nov 2008.