const char *lxc_global_config_value(const char *option_name)
{
static const char * const options[][2] = {
{ "lxc.bdev.lvm.vg", DEFAULT_VG },
{ "lxc.bdev.lvm.thin_pool", DEFAULT_THIN_POOL },
{ "lxc.bdev.zfs.root", DEFAULT_ZFSROOT },
{ "lxc.lxcpath", NULL },
{ "lxc.default_config", NULL },
{ "lxc.cgroup.pattern", DEFAULT_CGROUP_PATTERN },
{ "lxc.cgroup.use", NULL },
{ NULL, NULL },
};
/* placed in the thread local storage pool for non-bionic targets */
#ifdef HAVE_TLS
static __thread const char *values[sizeof(options) / sizeof(options[0])] = { 0 };
#else
static const char *values[sizeof(options) / sizeof(options[0])] = { 0 };
#endif
char *user_config_path = NULL;
char *user_default_config_path = NULL;
char *user_lxc_path = NULL;
if (geteuid() > 0) {
const char *user_home = getenv("HOME");
if (!user_home)
user_home = "/";
user_config_path = malloc(sizeof(char) * (22 + strlen(user_home)));
user_default_config_path = malloc(sizeof(char) * (26 + strlen(user_home)));
user_lxc_path = malloc(sizeof(char) * (19 + strlen(user_home)));
sprintf(user_config_path, "%s/.config/lxc/lxc.conf", user_home);
sprintf(user_default_config_path, "%s/.config/lxc/default.conf", user_home);
sprintf(user_lxc_path, "%s/.local/share/lxc/", user_home);
}
else {
user_config_path = strdup(LXC_GLOBAL_CONF);
user_default_config_path = strdup(LXC_DEFAULT_CONFIG);
user_lxc_path = strdup(LXCPATH);
}
const char * const (*ptr)[2];
size_t i;
char buf[1024], *p, *p2;
FILE *fin = NULL;
for (i = 0, ptr = options; (*ptr)[0]; ptr++, i++) {
if (!strcmp(option_name, (*ptr)[0]))
break;
}
if (!(*ptr)[0]) {
free(user_config_path);
free(user_default_config_path);
free(user_lxc_path);
errno = EINVAL;
return NULL;
}
if (values[i]) {
free(user_config_path);
free(user_default_config_path);
free(user_lxc_path);
return values[i];
}
fin = fopen_cloexec(user_config_path, "r");
free(user_config_path);
if (fin) {
while (fgets(buf, 1024, fin)) {
if (buf[0] == '#')
continue;
p = strstr(buf, option_name);
if (!p)
continue;
/* see if there was just white space in front
* of the option name
*/
for (p2 = buf; p2 < p; p2++) {
if (*p2 != ' ' && *p2 != '\t')
break;
}
if (p2 < p)
continue;
p = strchr(p, '=');
if (!p)
continue;
/* see if there was just white space after
* the option name
*/
for (p2 += strlen(option_name); p2 < p; p2++) {
if (*p2 != ' ' && *p2 != '\t')
break;
}
if (p2 < p)
continue;
p++;
while (*p && (*p == ' ' || *p == '\t')) p++;
if (!*p)
continue;
free(user_default_config_path);
if (strcmp(option_name, "lxc.lxcpath") == 0) {
free(user_lxc_path);
user_lxc_path = copy_global_config_value(p);
remove_trailing_slashes(user_lxc_path);
values[i] = user_lxc_path;
goto out;
}
values[i] = copy_global_config_value(p);
free(user_lxc_path);
goto out;
}
}
/* could not find value, use default */
if (strcmp(option_name, "lxc.lxcpath") == 0) {
remove_trailing_slashes(user_lxc_path);
values[i] = user_lxc_path;
free(user_default_config_path);
}
else if (strcmp(option_name, "lxc.default_config") == 0) {
values[i] = user_default_config_path;
free(user_lxc_path);
}
else {
free(user_default_config_path);
free(user_lxc_path);
values[i] = (*ptr)[1];
}
/* special case: if default value is NULL,
* and there is no config, don't view that
* as an error... */
if (!values[i])
errno = 0;
out:
if (fin)
fclose(fin);
return values[i];
}
const char *lxc_global_config_value(const char *option_name)
{
static const char *options[][2] = {
{ "lvm_vg", DEFAULT_VG },
{ "lvm_thin_pool", DEFAULT_THIN_POOL },
{ "zfsroot", DEFAULT_ZFSROOT },
{ "lxcpath", LXCPATH },
{ "cgroup.pattern", DEFAULT_CGROUP_PATTERN },
{ "cgroup.use", NULL },
{ NULL, NULL },
};
/* Protected by a mutex to eliminate conflicting load and store operations */
static const char *values[sizeof(options) / sizeof(options[0])] = { 0 };
const char *(*ptr)[2];
const char *value;
size_t i;
char buf[1024], *p, *p2;
FILE *fin = NULL;
for (i = 0, ptr = options; (*ptr)[0]; ptr++, i++) {
if (!strcmp(option_name, (*ptr)[0]))
break;
}
if (!(*ptr)[0]) {
errno = EINVAL;
return NULL;
}
static_lock();
if (values[i]) {
value = values[i];
static_unlock();
return value;
}
static_unlock();
process_lock();
fin = fopen_cloexec(LXC_GLOBAL_CONF, "r");
process_unlock();
if (fin) {
while (fgets(buf, 1024, fin)) {
if (buf[0] == '#')
continue;
p = strstr(buf, option_name);
if (!p)
continue;
/* see if there was just white space in front
* of the option name
*/
for (p2 = buf; p2 < p; p2++) {
if (*p2 != ' ' && *p2 != '\t')
break;
}
if (p2 < p)
continue;
p = strchr(p, '=');
if (!p)
continue;
/* see if there was just white space after
* the option name
*/
for (p2 += strlen(option_name); p2 < p; p2++) {
if (*p2 != ' ' && *p2 != '\t')
break;
}
if (p2 < p)
continue;
p++;
while (*p && (*p == ' ' || *p == '\t')) p++;
if (!*p)
continue;
static_lock();
values[i] = copy_global_config_value(p);
static_unlock();
goto out;
}
}
/* could not find value, use default */
static_lock();
values[i] = (*ptr)[1];
/* special case: if default value is NULL,
* and there is no config, don't view that
* as an error... */
if (!values[i])
errno = 0;
static_unlock();
out:
process_lock();
if (fin)
fclose(fin);
process_unlock();
static_lock();
value = values[i];
static_unlock();
return value;
}