Sun, 27 Jul 2014 21:04:57 +0200
Small fix
/***************************************************************************** * Copyright (C) 2014 * * Michiel Broek <mbroek at mbse dot eu> * * This file is part of the mbsePi-apps * * This 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, or (at your option) any * later version. * * mbsePi-apps 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 EC-65K; see the file COPYING. If not, write to the Free * Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. *****************************************************************************/ #include "lock.h" #include "thermferm.h" /* * Put a lock on this program. */ int lockprog(char *name) { char *tempfile, *lockfile; FILE *fp; pid_t oldpid; tempfile = calloc(PATH_MAX, sizeof(char)); lockfile = calloc(PATH_MAX, sizeof(char)); snprintf(tempfile, PATH_MAX, "/var/run/%s.tmp", name); snprintf(lockfile, PATH_MAX, "/var/run/%s.pid", name); if ((fp = fopen(tempfile, "w")) == NULL) { perror(name); printf("Can't create lockfile \"%s\"\n", tempfile); free(tempfile); free(lockfile); return 1; } fprintf(fp, "%10u\n", getpid()); fclose(fp); while (TRUE) { if (link(tempfile, lockfile) == 0) { unlink(tempfile); free(tempfile); free(lockfile); return 0; } if ((fp = fopen(lockfile, "r")) == NULL) { perror(name); printf("Can't open lockfile \"%s\"\n", tempfile); unlink(tempfile); free(tempfile); free(lockfile); return 1; } if (fscanf(fp, "%u", &oldpid) != 1) { perror(name); printf("Can't read old pid from \"%s\"\n", tempfile); fclose(fp); unlink(tempfile); free(tempfile); free(lockfile); return 1; } fclose(fp); if (kill(oldpid,0) == -1) { if (errno == ESRCH) { printf("Stale lock found for pid %u\n", oldpid); unlink(lockfile); /* no return, try lock again */ } else { perror(name); printf("Kill for %u failed\n",oldpid); unlink(tempfile); free(tempfile); free(lockfile); return 1; } } else { printf("Another %s is already running, pid=%u\n", name, oldpid); unlink(tempfile); free(tempfile); free(lockfile); return 1; } } } void ulockprog(char *name) { char *lockfile; pid_t oldpid; FILE *fp; lockfile = calloc(PATH_MAX, sizeof(char)); snprintf(lockfile, PATH_MAX, "/var/run/%s.pid", name); if ((fp = fopen(lockfile, "r")) == NULL) { syslog(LOG_NOTICE, "Can't open lockfile \"%s\"", lockfile); free(lockfile); return; } if (fscanf(fp, "%u", &oldpid) != 1) { syslog(LOG_NOTICE, "Can't read old pid from \"%s\"", lockfile); fclose(fp); unlink(lockfile); free(lockfile); return; } fclose(fp); if (oldpid == getpid()) { (void)unlink(lockfile); } free(lockfile); }