Fixes #9

mbpfan.init

@@ -77,23 +77,23 @@ case "$1" in
        status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
        ;;
   restart|force-reload)
-	log_daemon_msg "Restarting $DESC" "$NAME"
-	do_stop
-	case "$?" in
-	  0|1)
-		do_start
-		case "$?" in
-			0) log_end_msg 0 ;;
-			1) log_end_msg 1 ;; # Old process is still running
-			*) log_end_msg 1 ;; # Failed to start
-		esac
-		;;
-	  *)
-	  	# Failed to stop
-		log_end_msg 1
-		;;
-	esac
-	;;
+  	log_daemon_msg "Restarting $DESC" "$NAME"
+  	do_stop
+  	case "$?" in
+  	  0|1)
+  		do_start
+  		case "$?" in
+  			0) log_end_msg 0 ;;
+  			1) log_end_msg 1 ;; # Old process is still running
+  			*) log_end_msg 1 ;; # Failed to start
+  		esac
+  		;;
+  	  *)
+  	  	# Failed to stop
+  		log_end_msg 1
+  		;;
+  	esac
+  	;;
   *)
 	echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
 	exit 3

src/daemon.c

 /**
- * Credits: http://peterlombardo.wikidot.com/linux-daemon-in-c
+ *  Copyright (C) 2012  Peter Lombardo <http://peterlombardo.wikidot.com/linux-daemon-in-c>
+ *  Modifications (2012) by Daniel Graziotin <dgraziotin@task3.cc>
+ *
+ *  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 3 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.
+ *
  */
 
+
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <stdio.h>
@@ -16,8 +29,33 @@
 #include "mbpfan.h"
 #include "global.h"
 
-#define DAEMON_NAME "mbpfan"
-#define PID_FILE "/var/run/mbpfan.pid"
+int write_pid(int pid){
+        FILE *file = NULL;
+        file = fopen(program_pid, "w");
+        if(file != NULL) {
+                fprintf(file, "%d", pid);
+                fclose(file);
+                return 1;
+        }else{
+                return 0;
+        }            
+}
+
+int read_pid(){
+        FILE *file = NULL;
+        int pid = -1;
+        file = fopen(program_pid, "r");
+        if(file != NULL) {
+                fscanf(file, "%d", &pid);
+                fclose(file);
+                return pid;
+        }
+        return -1;           
+}
+
+int delete_pid(){
+        return remove(program_pid);
+}
 
 
 void signal_handler(int signal)
@@ -27,15 +65,18 @@ void signal_handler(int signal)
         case SIGHUP:
                 //TODO: restart myself
                 syslog(LOG_WARNING, "Received SIGHUP signal.");
+                delete_pid();
                 exit(0);
                 break;
         case SIGTERM:
                 syslog(LOG_WARNING, "Received SIGTERM signal.");
+                delete_pid();
                 //TODO: free resources
                 exit(0);
                 break;
         case SIGINT:
                 syslog(LOG_WARNING, "Received SIGINT signal.");
+                delete_pid();
                 //TODO: free resources
                 exit(0);
         default:
@@ -44,8 +85,7 @@ void signal_handler(int signal)
         }
 }
 
-
-void go_daemon(void (*function)())
+void go_daemon(void (*mbpfan)())
 {
 
         // Setup signal handling before we start
@@ -53,36 +93,37 @@ void go_daemon(void (*function)())
         signal(SIGTERM, signal_handler);
         signal(SIGINT, signal_handler);
 
-        syslog(LOG_INFO, "%s starting up", DAEMON_NAME);
+        syslog(LOG_INFO, "%s starting up", program_name);
 
         // Setup syslog logging - see SETLOGMASK(3)
         if(verbose) {
                 setlogmask(LOG_UPTO(LOG_DEBUG));
-                openlog(DAEMON_NAME, LOG_CONS | LOG_NDELAY | LOG_PERROR | LOG_PID, LOG_USER);
+                openlog(program_name, LOG_CONS | LOG_NDELAY | LOG_PERROR | LOG_PID, LOG_USER);
         } else {
                 setlogmask(LOG_UPTO(LOG_INFO));
-                openlog(DAEMON_NAME, LOG_CONS, LOG_USER);
+                openlog(program_name, LOG_CONS, LOG_USER);
         }
 
 
-        pid_t pid;
-        pid_t sid;
+        pid_t pid_slave;
+        pid_t sid_slave;
 
         if (daemonize) {
 
-                pid = fork();
-                if (pid < 0) {
+                pid_slave = fork();
+                if (pid_slave < 0) {
                         exit(EXIT_FAILURE);
                 }
-                if (pid > 0) {
-                        exit(EXIT_SUCCESS);
+                if (pid_slave > 0) {
+                   // kill the father
+                   exit(EXIT_SUCCESS);
                 }
 
-                umask(0);
+                umask(0022);
 
-                // new SID for the child process
-                sid = setsid();
-                if (sid < 0) {
+                // new sid_slave for the child process
+                sid_slave = setsid();
+                if (sid_slave < 0) {
                         exit(EXIT_FAILURE);
                 }
 
@@ -90,17 +131,48 @@ void go_daemon(void (*function)())
                         exit(EXIT_FAILURE);
                 }
 
+
+
                 /* Close out the standard file descriptors */
                 close(STDIN_FILENO);
                 close(STDOUT_FILENO);
                 close(STDERR_FILENO);
         }
+        
 
+        int current_pid = getpid();
+
+        if (read_pid() == -1){
+                if (verbose){
+                        printf("Writing a new .pid file with value %d at: %s", current_pid, program_pid);
+                        syslog(LOG_INFO, "Writing a new .pid file with value %d at: %s", current_pid, program_pid);
+                }
+                if (write_pid(current_pid) == 0){
+                        syslog(LOG_ERR, "Can not create a .pid file at: %s. Aborting", program_pid);  
+                        if (verbose){
+                                printf("ERROR: Can not create a .pid file at: %s. Aborting", program_pid);
+                        }     
+                     exit(EXIT_FAILURE);
+                }else{
+                        if (verbose){
+                                printf("Successfully written a new .pid file with value %d at: %s", current_pid, program_pid);   
+                                syslog(LOG_INFO, "Successfully written a new .pid file with value %d at: %s", current_pid, program_pid);   
+                        }
+                }
+        }else{
+                syslog(LOG_ERR, "A previously created .pid file exists at: %s. Aborting", program_pid);
+                if (verbose){
+                    printf("ERROR: a previously created .pid file exists at: %s.\n Aborting\n", program_pid);  
+                }
+                exit(EXIT_FAILURE);  
+        }
+        
 
-        function();
+        mbpfan();
 
-        if(daemonize)
-                syslog(LOG_INFO, "%s daemon exiting", DAEMON_NAME);
+        if(daemonize){
+                syslog(LOG_INFO, "%s daemon exiting", program_name);
+        }
 
         return;
 }

src/daemon.h

+/**
+ *  Copyright (C) (2012) Daniel Graziotin <dgraziotin@task3.cc>
+ *
+ *  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 3 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.
+ *
+ */
+
+
+/**
+ * Write the PID of the forked daemon to the
+ * .pid file defined in char *program_pid
+ * Return TRUE on success
+ * Return FALSE otherwise
+ */
+int write_pid(int pid);
+
+/**
+ * Read PID of the forked daemon from the
+ * .pid file defined in char *program_pid
+ * Return the pid on success
+ * Return -1 otherwise
+ */
+int read_pid();
+
+/**
+ * Deletes the .pid file defined in
+ * char *program_pid
+ * Return TRUE on success
+ * Return FALSE otherwise
+ */
+ int delete_pid();
+
 /**
  * ...handles signals :-)
  */
 void signal_handler(int signal);
 
+
 /**
  * Daemonizes
  */

src/global.h

 extern int daemonize;
-extern int verbose;
+extern int verbose;
\ No newline at end of file
+
+extern const char* program_name;
+extern const char* program_pid;
\ No newline at end of file

src/main.c

+/**
+ *  Copyright (C) (2012) Daniel Graziotin <dgraziotin@task3.cc>
+ *
+ *  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 3 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.
+ *
+ */
+ 
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -8,6 +23,9 @@
 int daemonize = 1;
 int verbose = 0;
 
+const char *program_name = "mbpfan";
+const char *program_pid = "/var/run/mbpfan.pid";
+
 void print_usage(int argc, char *argv[])
 {
         if (argc >=1) {
@@ -44,7 +62,7 @@ int main(int argc, char *argv[])
         }
 
         // pointer to mbpfan() function in mbpfan.c
-        void (*function)() = mbpfan;
-        go_daemon(function);
+        void (*mbpfan)() = mbpfan;
+        go_daemon(mbpfan);
         exit(0);
 }
\ No newline at end of file

src/mbpfan.c

@@ -18,7 +18,7 @@
  *
  *  Notes:
  *    Assumes any number of processors and fans (max. 10)
- *    It Uses only the temperatures from the processors as input.
+ *    It uses only the temperatures from the processors as input.
  *    Requires coretemp and applesmc kernel modules to be loaded.
  *    Requires root use
  *

src/mbpfan.h

+/**
+ *  Copyright (C) 2010  Allan McRae <allan@archlinux.org>
+ *  Modifications (2012) by Daniel Graziotin <dgraziotin@task3.cc>
+ *
+ *  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 3 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.
+ *
+ */
+
 /** Basic fan speed parameters
  */
 extern int min_fan_speed;