void sigint_allow(void)
{
struct sigaction handler;
sigset_t sigs;
if (memlock_count_daemon())
return;
/*
* Do not overwrite the backed-up handler data -
* just increase nesting count.
*/
if (++_handler_installed >= MAX_SIGINTS)
return;
/* Grab old sigaction for SIGINT: shall not fail. */
if (sigaction(SIGINT, NULL, &handler))
log_sys_debug("sigaction", "SIGINT");
handler.sa_flags &= ~SA_RESTART; /* Clear restart flag */
handler.sa_handler = _catch_sigint;
/* Override the signal handler: shall not fail. */
if (sigaction(SIGINT, &handler, &_oldhandler[_handler_installed - 1]))
log_sys_debug("sigaction", "SIGINT");
/* Unmask SIGINT. Remember to mask it again on restore. */
if (sigprocmask(0, NULL, &sigs))
log_sys_debug("sigprocmask", "");
if ((_oldmasked[_handler_installed] = sigismember(&sigs, SIGINT))) {
sigdelset(&sigs, SIGINT);
if (sigprocmask(SIG_SETMASK, &sigs, NULL))
log_sys_debug("sigprocmask", "SIG_SETMASK");
}
}
void sigint_restore(void)
{
if (memlock_count_daemon())
return;
if (!_handler_installed ||
--_handler_installed >= MAX_SIGINTS)
return;
/* Nesting count went below MAX_SIGINTS. */
if (_oldmasked[_handler_installed]) {
sigset_t sigs;
sigprocmask(0, NULL, &sigs);
sigaddset(&sigs, SIGINT);
if (sigprocmask(SIG_SETMASK, &sigs, NULL))
log_sys_debug("sigprocmask", "SIG_SETMASK");
}
if (sigaction(SIGINT, &_oldhandler[_handler_installed], NULL))
log_sys_debug("sigaction", "SIGINT restore");
}
/*
* Support envvar LVM_LOG_FILE_EPOCH and allow to attach
* extra keyword (consist of upto 32 alpha chars) to
* opened log file. After this 'epoch' word pid and starttime
* (in kernel units, read from /proc/self/stat)
* is automatically attached.
* If command/daemon forks multiple times, it could create multiple
* log files ensuring, there are no overwrites.
*/
void init_log_file(const char *log_file, int append)
{
static const char statfile[] = "/proc/self/stat";
const char *env;
int pid;
unsigned long long starttime;
FILE *st;
int i = 0;
_log_file_path[0] = '\0';
if ((env = getenv("LVM_LOG_FILE_EPOCH"))) {
while (isalpha(env[i]) && i < 32) /* Up to 32 alphas */
i++;
if (env[i]) {
if (i)
log_warn("WARNING: Ignoring invalid LVM_LOG_FILE_EPOCH envvar \"%s\".", env);
goto no_epoch;
}
if (!(st = fopen(statfile, "r")))
log_sys_error("fopen", statfile);
else if (fscanf(st, "%d %*s %*c %*d %*d %*d %*d " /* tty_nr */
"%*d %*u %*u %*u %*u " /* mjflt */
"%*u %*u %*u %*d %*d " /* cstim */
"%*d %*d %*d %*d " /* itrealvalue */
"%llu", &pid, &starttime) != 2) {
log_warn("WARNING: Cannot parse content of %s.", statfile);
} else {
if (dm_snprintf(_log_file_path, sizeof(_log_file_path),
"%s_%s_%d_%lld", log_file, env, pid, starttime) < 0) {
log_warn("WARNING: Debug log file path is too long for epoch.");
_log_file_path[0] = '\0';
} else {
log_file = _log_file_path;
append = 1; /* force */
}
}
if (st && fclose(st))
log_sys_debug("fclose", statfile);
}
no_epoch:
if (!(_log_file = fopen(log_file, append ? "a" : "w"))) {
log_sys_error("fopen", log_file);
return;
}
_log_to_file = 1;
}
static int _sysfs_get_kvdo_value(const char *dm_name, const char *vdo_param, uint64_t *value)
{
char path[PATH_MAX];
char temp[64];
int fd, size, r = 0;
if (dm_snprintf(path, sizeof(path), "%skvdo/%s/%s",
dm_sysfs_dir(), dm_name, vdo_param) < 0) {
log_error("Failed to build kmod path.");
return 0;
}
if ((fd = open(path, O_RDONLY)) < 0) {
if (errno != ENOENT)
log_sys_error("open", path);
else
log_sys_debug("open", path);
goto bad;
}
if ((size = read(fd, temp, sizeof(temp) - 1)) < 0) {
log_sys_error("read", path);
goto bad;
}
temp[size] = 0;
errno = 0;
*value = strtoll(temp, NULL, 0);
if (errno) {
log_sys_error("strtool", path);
goto bad;
}
r = 1;
bad:
if (fd >= 0 && close(fd))
log_sys_error("close", path);
return r;
}
int dev_open_flags(struct device *dev, int flags, int direct, int quiet)
{
struct stat buf;
const char *name;
int need_excl = 0, need_rw = 0;
if ((flags & O_ACCMODE) == O_RDWR)
need_rw = 1;
if ((flags & O_EXCL))
need_excl = 1;
if (dev->fd >= 0) {
if (((dev->flags & DEV_OPENED_RW) || !need_rw) &&
((dev->flags & DEV_OPENED_EXCL) || !need_excl)) {
dev->open_count++;
return 1;
}
if (dev->open_count && !need_excl) {
/* FIXME Ensure we never get here */
log_error(INTERNAL_ERROR "%s already opened read-only",
dev_name(dev));
dev->open_count++;
}
dev_close_immediate(dev);
}
if (critical_section())
/* FIXME Make this log_error */
log_verbose("dev_open(%s) called while suspended",
dev_name(dev));
if (dev->flags & DEV_REGULAR)
name = dev_name(dev);
else if (!(name = dev_name_confirmed(dev, quiet)))
return_0;
if (!(dev->flags & DEV_REGULAR)) {
if (stat(name, &buf) < 0) {
log_sys_error("%s: stat failed", name);
return 0;
}
if (buf.st_rdev != dev->dev) {
log_error("%s: device changed", name);
return 0;
}
}
#ifdef O_DIRECT_SUPPORT
if (direct) {
if (!(dev->flags & DEV_O_DIRECT_TESTED))
dev->flags |= DEV_O_DIRECT;
if ((dev->flags & DEV_O_DIRECT))
flags |= O_DIRECT;
}
#endif
#ifdef O_NOATIME
/* Don't update atime on device inodes */
if (!(dev->flags & DEV_REGULAR))
flags |= O_NOATIME;
#endif
if ((dev->fd = open(name, flags, 0777)) < 0) {
#ifdef O_DIRECT_SUPPORT
if (direct && !(dev->flags & DEV_O_DIRECT_TESTED)) {
flags &= ~O_DIRECT;
if ((dev->fd = open(name, flags, 0777)) >= 0) {
dev->flags &= ~DEV_O_DIRECT;
log_debug("%s: Not using O_DIRECT", name);
goto opened;
}
}
#endif
if (quiet)
log_sys_debug("open", name);
else
log_sys_error("open", name);
return 0;
}
#ifdef O_DIRECT_SUPPORT
opened:
if (direct)
dev->flags |= DEV_O_DIRECT_TESTED;
#endif
dev->open_count++;
dev->flags &= ~DEV_ACCESSED_W;
if (need_rw)
dev->flags |= DEV_OPENED_RW;
else
dev->flags &= ~DEV_OPENED_RW;
if (need_excl)
dev->flags |= DEV_OPENED_EXCL;
else
dev->flags &= ~DEV_OPENED_EXCL;
if (!(dev->flags & DEV_REGULAR) &&
((fstat(dev->fd, &buf) < 0) || (buf.st_rdev != dev->dev))) {
log_error("%s: fstat failed: Has device name changed?", name);
dev_close_immediate(dev);
return 0;
}
#ifndef O_DIRECT_SUPPORT
if (!(dev->flags & DEV_REGULAR))
dev_flush(dev);
#endif
if ((flags & O_CREAT) && !(flags & O_TRUNC))
dev->end = lseek(dev->fd, (off_t) 0, SEEK_END);
dm_list_add(&_open_devices, &dev->open_list);
log_debug("Opened %s %s%s%s", dev_name(dev),
dev->flags & DEV_OPENED_RW ? "RW" : "RO",
dev->flags & DEV_OPENED_EXCL ? " O_EXCL" : "",
dev->flags & DEV_O_DIRECT ? " O_DIRECT" : "");
return 1;
}
static unsigned long _dev_topology_attribute(struct dev_types *dt,
const char *attribute,
struct device *dev,
unsigned long default_value)
{
const char *sysfs_dir = dm_sysfs_dir();
char path[PATH_MAX], buffer[64];
FILE *fp;
struct stat info;
dev_t uninitialized_var(primary);
unsigned long result = default_value;
unsigned long value = 0UL;
if (!attribute || !*attribute)
goto_out;
if (!sysfs_dir || !*sysfs_dir)
goto_out;
if (!_snprintf_attr(path, sizeof(path), sysfs_dir, attribute, dev->dev))
goto_out;
/*
* check if the desired sysfs attribute exists
* - if not: either the kernel doesn't have topology support
* or the device could be a partition
*/
if (stat(path, &info) == -1) {
if (errno != ENOENT) {
log_sys_debug("stat", path);
goto out;
}
if (!dev_get_primary_dev(dt, dev, &primary))
goto out;
/* get attribute from partition's primary device */
if (!_snprintf_attr(path, sizeof(path), sysfs_dir, attribute, primary))
goto_out;
if (stat(path, &info) == -1) {
if (errno != ENOENT)
log_sys_debug("stat", path);
goto out;
}
}
if (!(fp = fopen(path, "r"))) {
log_sys_debug("fopen", path);
goto out;
}
if (!fgets(buffer, sizeof(buffer), fp)) {
log_sys_debug("fgets", path);
goto out_close;
}
if (sscanf(buffer, "%lu", &value) != 1) {
log_warn("sysfs file %s not in expected format: %s", path, buffer);
goto out_close;
}
log_very_verbose("Device %s: %s is %lu%s.",
dev_name(dev), attribute, result, default_value ? "" : " bytes");
result = value >> SECTOR_SHIFT;
out_close:
if (fclose(fp))
log_sys_debug("fclose", path);
out:
return result;
}
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;
}
snprintf(buffer, sizeof(buffer), "%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;
}
/* coverity[leaked_handle] intentional leak of fd handle here */
return 1;
fail_close_unlink:
if (unlink(lockfile))
log_sys_debug("unlink", lockfile);
fail_close:
if (close(fd))
log_sys_debug("close", lockfile);
return 0;
}