--- /dev/null
+// -*- mode:C; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <errno.h>
+
+#include "objclass/objclass.h"
+
+#include "cls/version/cls_version_ops.h"
+
+#include "include/compat.h"
+
+CLS_VER(1,0)
+CLS_NAME(version)
+
+
+#define VERSION_ATTR "ceph.objclass.version"
+
+static int set_version(cls_method_context_t hctx, struct obj_version *objv)
+{
+ bufferlist bl;
+
+ ::encode(*objv, bl);
+
+ CLS_LOG(20, "cls_version: set_version %s:%d", objv->tag.c_str(), (int)objv->ver);
+
+ int ret = cls_cxx_setxattr(hctx, VERSION_ATTR, &bl);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int init_version(cls_method_context_t hctx, struct obj_version *objv)
+{
+#define TAG_LEN 24
+ char buf[TAG_LEN + 1];
+
+ int ret = cls_gen_rand_base64(buf, sizeof(buf));
+ if (ret < 0)
+ return ret;
+
+ objv->ver = 1;
+ objv->tag = buf;
+
+ CLS_LOG(20, "cls_version: init_version %s:%d", objv->tag.c_str(), (int)objv->ver);
+
+ return set_version(hctx, objv);
+}
+
+/* implicit create should be true only if called from a write operation (set, inc), never from a read operation (read, check) */
+static int read_version(cls_method_context_t hctx, obj_version *objv, bool implicit_create)
+{
+ bufferlist bl;
+ int ret = cls_cxx_getxattr(hctx, VERSION_ATTR, &bl);
+ if (ret == -ENOENT || ret == -ENODATA) {
+ objv->ver = 0;
+
+ if (implicit_create) {
+ return init_version(hctx, objv);
+ }
+ return 0;
+ }
+ if (ret < 0)
+ return ret;
+
+ try {
+ bufferlist::iterator iter = bl.begin();
+ ::decode(*objv, iter);
+ } catch (buffer::error& err) {
+ CLS_LOG(0, "ERROR: read_version(): failed to decode version entry\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int cls_version_set(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist::iterator in_iter = in->begin();
+
+ cls_version_set_op op;
+ try {
+ ::decode(op, in_iter);
+ } catch (buffer::error& err) {
+ CLS_LOG(1, "ERROR: cls_version_get(): failed to decode entry\n");
+ return -EINVAL;
+ }
+
+ int ret = set_version(hctx, &op.objv);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static bool check_conds(list<obj_version_cond>& conds, obj_version& objv)
+{
+ if (conds.empty())
+ return true;
+
+ for (list<obj_version_cond>::iterator iter = conds.begin(); iter != conds.end(); ++iter) {
+ obj_version_cond& cond = *iter;
+ obj_version& v = cond.ver;
+ CLS_LOG(20, "cls_version: check_version %s:%d (cond=%d)", v.tag.c_str(), (int)v.ver, (int)cond.cond);
+
+ switch (cond.cond) {
+ case VER_COND_NONE:
+ break;
+ case VER_COND_EQ:
+ if (!objv.compare(&v))
+ return false;
+ break;
+ case VER_COND_GT:
+ if (!(objv.ver > v.ver))
+ return false;
+ break;
+ case VER_COND_GE:
+ if (!(objv.ver >= v.ver))
+ return false;
+ break;
+ case VER_COND_LT:
+ if (!(objv.ver < v.ver))
+ return false;
+ break;
+ case VER_COND_LE:
+ if (!(objv.ver <= v.ver))
+ return false;
+ break;
+ case VER_COND_TAG_EQ:
+ if (objv.tag.compare(v.tag) != 0)
+ return false;
+ break;
+ case VER_COND_TAG_NE:
+ if (objv.tag.compare(v.tag) == 0)
+ return false;
+ break;
+ }
+ }
+
+ return true;
+}
+
+static int cls_version_inc(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist::iterator in_iter = in->begin();
+
+ cls_version_inc_op op;
+ try {
+ ::decode(op, in_iter);
+ } catch (buffer::error& err) {
+ CLS_LOG(1, "ERROR: cls_version_get(): failed to decode entry\n");
+ return -EINVAL;
+ }
+
+ obj_version objv;
+ int ret = read_version(hctx, &objv, true);
+ if (ret < 0)
+ return ret;
+
+ if (!check_conds(op.conds, objv)) {
+ return -ECANCELED;
+ }
+ objv.inc();
+
+ ret = set_version(hctx, &objv);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int cls_version_check(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ bufferlist::iterator in_iter = in->begin();
+
+ cls_version_check_op op;
+ try {
+ ::decode(op, in_iter);
+ } catch (buffer::error& err) {
+ CLS_LOG(1, "ERROR: cls_version_get(): failed to decode entry\n");
+ return -EINVAL;
+ }
+
+ obj_version objv;
+ int ret = read_version(hctx, &objv, false);
+ if (ret < 0)
+ return ret;
+ CLS_LOG(20, "cls_version: read_version %s:%d", objv.tag.c_str(), (int)objv.ver);
+
+ if (!check_conds(op.conds, objv)) {
+ CLS_LOG(20, "cls_version: failed condition check");
+ return -ECANCELED;
+ }
+
+ return 0;
+}
+
+static int cls_version_read(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+ obj_version objv;
+
+ cls_version_read_ret read_ret;
+ int ret = read_version(hctx, &read_ret.objv, false);
+ if (ret < 0)
+ return ret;
+
+ ::encode(read_ret, *out);
+
+ return 0;
+}
+
+CLS_INIT(version)
+{
+ CLS_LOG(1, "Loaded version class!");
+
+ cls_handle_t h_class;
+ cls_method_handle_t h_version_set;
+ cls_method_handle_t h_version_inc;
+ cls_method_handle_t h_version_inc_conds;
+ cls_method_handle_t h_version_read;
+ cls_method_handle_t h_version_check_conds;
+
+ cls_register("version", &h_class);
+
+ /* version */
+ cls_register_cxx_method(h_class, "set", CLS_METHOD_RD | CLS_METHOD_WR, cls_version_set, &h_version_set);
+ cls_register_cxx_method(h_class, "inc", CLS_METHOD_RD | CLS_METHOD_WR, cls_version_inc, &h_version_inc);
+ cls_register_cxx_method(h_class, "inc_conds", CLS_METHOD_RD | CLS_METHOD_WR, cls_version_inc, &h_version_inc_conds);
+ cls_register_cxx_method(h_class, "read", CLS_METHOD_RD, cls_version_read, &h_version_read);
+ cls_register_cxx_method(h_class, "check_conds", CLS_METHOD_RD, cls_version_check, &h_version_check_conds);
+
+ return;
+}
+
Code Review / stor4nfv.git / blobdiff