int lvm_snapshot(const char *orig, const char *path, uint64_t size)
{
int ret;
char *pathdup, *lv;
char sz[24];
char cmd_output[MAXPATHLEN];
struct lvcreate_args cmd_args = {0};
ret = snprintf(sz, 24, "%" PRIu64 "b", size);
if (ret < 0 || ret >= 24) {
ERROR("Failed to create string");
return -1;
}
pathdup = strdup(path);
if (!pathdup) {
ERROR("Failed to duplicate string \"%s\"", path);
return -1;
}
lv = strrchr(pathdup, '/');
if (!lv) {
ERROR("Failed to detect \"/\" in string \"%s\"", pathdup);
free(pathdup);
return -1;
}
*lv = '\0';
lv++;
TRACE("Parsed logical volume \"%s\"", lv);
/* Check if the original logical volume is backed by a thinpool, in
* which case we cannot specify a size that's different from the
* original size.
*/
ret = lvm_is_thin_volume(orig);
if (ret < 0) {
free(pathdup);
return -1;
} else if (ret) {
cmd_args.thinpool = orig;
}
cmd_args.lv = lv;
cmd_args.source_lv = orig;
cmd_args.size = sz;
TRACE("Creating new lvm snapshot \"%s\" of \"%s\" with size \"%s\"", lv,
orig, sz);
ret = run_command(cmd_output, sizeof(cmd_output),
lvm_snapshot_exec_wrapper, (void *)&cmd_args);
if (ret < 0) {
ERROR("Failed to create logical volume \"%s\": %s", orig,
cmd_output);
free(pathdup);
return -1;
}
free(pathdup);
return 0;
}
int lvm_snapshot(const char *orig, const char *path, uint64_t size)
{
int ret, pid;
char sz[24], *pathdup, *lv;
if ((pid = fork()) < 0) {
SYSERROR("failed fork");
return -1;
}
if (pid > 0)
return wait_for_pid(pid);
// specify bytes to lvcreate
ret = snprintf(sz, 24, "%"PRIu64"b", size);
if (ret < 0 || ret >= 24)
exit(EXIT_FAILURE);
pathdup = strdup(path);
if (!pathdup)
exit(EXIT_FAILURE);
lv = strrchr(pathdup, '/');
if (!lv) {
free(pathdup);
exit(EXIT_FAILURE);
}
*lv = '\0';
lv++;
// check if the original lv is backed by a thin pool, in which case we
// cannot specify a size that's different from the original size.
ret = lvm_is_thin_volume(orig);
if (ret == -1) {
free(pathdup);
return -1;
}
if (!ret) {
ret = execlp("lvcreate", "lvcreate", "-s", "-L", sz, "-n", lv, orig, (char *)NULL);
} else {
ret = execlp("lvcreate", "lvcreate", "-s", "-n", lv, orig, (char *)NULL);
}
free(pathdup);
exit(EXIT_FAILURE);
}
