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/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This file is part of the device-mapper userspace tools.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser 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 "dmlib.h"
#include <sys/file.h>
#include <fcntl.h>
#include <dirent.h>
static int _create_dir_recursive(const char *dir)
{
char *orig, *s;
int rc, r = 0;
log_verbose("Creating directory \"%s\"", dir);
/* Create parent directories */
orig = s = dm_strdup(dir);
if (!s) {
log_error("Failed to duplicate directory name.");
return 0;
}
while ((s = strchr(s, '/')) != NULL) {
*s = '\0';
if (*orig) {
rc = mkdir(orig, 0777);
if (rc < 0 && errno != EEXIST) {
if (errno != EROFS)
log_sys_error("mkdir", orig);
goto out;
}
}
*s++ = '/';
}
/* Create final directory */
rc = mkdir(dir, 0777);
if (rc < 0 && errno != EEXIST) {
if (errno != EROFS)
log_sys_error("mkdir", orig);
goto out;
}
r = 1;
out:
dm_free(orig);
return r;
}
int dm_create_dir(const char *dir)
{
struct stat info;
if (!*dir)
return 1;
if (stat(dir, &info) < 0)
return _create_dir_recursive(dir);
if (S_ISDIR(info.st_mode))
return 1;
log_error("Directory \"%s\" not found", dir);
return 0;
}
int dm_is_empty_dir(const char *dir)
{
struct dirent *dirent;
DIR *d;
if (!(d = opendir(dir))) {
log_sys_error("opendir", dir);
return 0;
}
while ((dirent = readdir(d)))
if (strcmp(dirent->d_name, ".") && strcmp(dirent->d_name, ".."))
break;
if (closedir(d))
log_sys_error("closedir", dir);
return dirent ? 0 : 1;
}
int dm_fclose(FILE *stream)
{
int prev_fail = ferror(stream);
int fclose_fail = fclose(stream);
/* If there was a previous failure, but fclose succeeded,
clear errno, since ferror does not set it, and its value
may be unrelated to the ferror-reported failure. */
if (prev_fail && !fclose_fail)
errno = 0;
return prev_fail || fclose_fail ? EOF : 0;
}
int dm_create_lockfile(const char *lockfile)
{
int fd, value;
size_t bufferlen;
ssize_t write_out;
struct flock lock;
char buffer[50];
int retries = 0;
if((fd = open(lockfile, O_CREAT | O_WRONLY,
(S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH))) < 0) {
log_error("Cannot open lockfile [%s], error was [%s]",
lockfile, strerror(errno));
return 0;
}
lock.l_type = F_WRLCK;
lock.l_start = 0;
lock.l_whence = SEEK_SET;
lock.l_len = 0;
retry_fcntl:
if (fcntl(fd, F_SETLK, &lock) < 0) {
switch (errno) {
case EINTR:
goto retry_fcntl;
case EACCES:
case EAGAIN:
if (retries == 20) {
log_error("Cannot lock lockfile [%s], error was [%s]",
lockfile, strerror(errno));
break;
} else {
++ retries;
usleep(1000);
goto retry_fcntl;
}
default:
log_error("process is already running");
}
goto fail_close;
}
if (ftruncate(fd, 0) < 0) {
log_error("Cannot truncate pidfile [%s], error was [%s]",
lockfile, strerror(errno));
goto fail_close_unlink;
}
memset(buffer, 0, sizeof(buffer));
snprintf(buffer, sizeof(buffer)-1, "%u\n", getpid());
bufferlen = strlen(buffer);
write_out = write(fd, buffer, bufferlen);
if ((write_out < 0) || (write_out == 0 && errno)) {
log_error("Cannot write pid to pidfile [%s], error was [%s]",
lockfile, strerror(errno));
goto fail_close_unlink;
}
if ((write_out == 0) || ((size_t)write_out < bufferlen)) {
log_error("Cannot write pid to pidfile [%s], shortwrite of"
"[%" PRIsize_t "] bytes, expected [%" PRIsize_t "]\n",
lockfile, write_out, bufferlen);
goto fail_close_unlink;
}
if ((value = fcntl(fd, F_GETFD, 0)) < 0) {
log_error("Cannot get close-on-exec flag from pidfile [%s], "
"error was [%s]", lockfile, strerror(errno));
goto fail_close_unlink;
}
value |= FD_CLOEXEC;
if (fcntl(fd, F_SETFD, value) < 0) {
log_error("Cannot set close-on-exec flag from pidfile [%s], "
"error was [%s]", lockfile, strerror(errno));
goto fail_close_unlink;
}
return 1;
fail_close_unlink:
if (unlink(lockfile))
stack;
fail_close:
if (close(fd))
stack;
return 0;
}
int dm_daemon_is_running(const char* lockfile)
{
int fd;
struct flock lock;
if((fd = open(lockfile, O_RDONLY)) < 0)
return 0;
lock.l_type = F_WRLCK;
lock.l_start = 0;
lock.l_whence = SEEK_SET;
lock.l_len = 0;
if (fcntl(fd, F_GETLK, &lock) < 0) {
log_error("Cannot check lock status of lockfile [%s], error was [%s]",
lockfile, strerror(errno));
if (close(fd))
stack;
return 0;
}
if (close(fd))
stack;
return (lock.l_type == F_UNLCK) ? 0 : 1;
}
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