-class Memcache
-{
-public:
-
- Memcache()
- :
- memc(),
- result()
- {
- memcached_create(&memc);
- }
-
- Memcache(memcached_st *clone)
- :
- memc(),
- result()
- {
- memcached_clone(&memc, clone);
- }
-
- Memcache(const Memcache &rhs)
- :
- memc(),
- result()
- {
- memcached_clone(&memc, const_cast<memcached_st *>(&rhs.getImpl()));
- }
-
- ~Memcache()
- {
- memcached_free(&memc);
- }
-
- /**
- * Get the internal memcached_st *
- */
- memcached_st &getImpl()
- {
- return memc;
- }
-
- /**
- * Get the internal memcached_st *
- */
- const memcached_st &getImpl() const
- {
- return memc;
- }
-
- /**
- * Return an error string for the given return structure.
- *
- * @param[in] rc a memcached_return structure
- * @return error string corresponding to given return code in the library.
- */
- const std::string getError(memcached_return rc) const
- {
- /* first parameter to strerror is unused */
- return memcached_strerror(NULL, rc);
- }
-
- bool fetch(std::string &key,
- std::vector<char> &ret_val,
- uint32_t *flags,
- memcached_return *rc)
- {
- char ret_key[MEMCACHED_MAX_KEY];
- size_t value_length= 0;
- size_t key_length= 0;
- char *value= memcached_fetch(&memc, ret_key, &key_length,
- &value_length, flags, rc);
- if (value && ret_val.empty())
- {
- ret_val.reserve(value_length);
- ret_val.assign(value, value + value_length);
- key.assign(ret_key);
- return true;
- }
- return false;
- }
-
- std::vector<char> &get(const std::string &key,
- std::vector<char> &ret_val)
- {
- uint32_t flags= 0;
- memcached_return rc;
- size_t value_length= 0;
-
- if (key.empty())
- {
- return ret_val;
- }
- char *value= memcached_get(&memc, key.c_str(), key.length(),
- &value_length, &flags, &rc);
- if (value != NULL && ret_val.empty())
- {
- ret_val.reserve(value_length);
- ret_val.assign(value, value + value_length);
- }
- return ret_val;
- }
-
- std::vector<char> &getByKey(const std::string &master_key,
- const std::string &key,
- std::vector<char> &ret_val)
- {
- uint32_t flags= 0;
- memcached_return rc;
- size_t value_length= 0;
-
- if (master_key.empty() || key.empty())
- {
- return ret_val;
- }
- char *value= memcached_get_by_key(&memc,
- master_key.c_str(), master_key.length(),
- key.c_str(), key.length(),
- &value_length, &flags, &rc);
- if (value)
- {
- ret_val.reserve(value_length);
- ret_val.assign(value, value + value_length);
- }
- return ret_val;
- }
-
- bool mget(std::vector<std::string> &keys)
- {
- std::vector<const char *> real_keys;
- std::vector<size_t> key_len;
- /*
- * Construct an array which will contain the length
- * of each of the strings in the input vector. Also, to
- * interface with the memcached C API, we need to convert
- * the vector of std::string's to a vector of char *.
- */
- real_keys.reserve(keys.size());
- key_len.reserve(keys.size());
-
- std::vector<std::string>::iterator it= keys.begin();
-
- while (it != keys.end())
- {
- real_keys.push_back(const_cast<char *>((*it).c_str()));
- key_len.push_back((*it).length());
- ++it;
- }
-
- /*
- * If the std::vector of keys is empty then we cannot
- * call memcached_mget as we will get undefined behavior.
- */
- if (! real_keys.empty())
- {
- memcached_return rc= memcached_mget(&memc, &real_keys[0], &key_len[0],
- real_keys.size());
- return (rc == MEMCACHED_SUCCESS);
- }
-
- return false;
- }
-
- bool set(const std::string &key,
- const std::vector<char> &value,
- time_t expiration,
- uint32_t flags)
- {
- if (key.empty() || value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_set(&memc,
- key.c_str(), key.length(),
- &value[0], value.size(),
- expiration, flags);
- return (rc == MEMCACHED_SUCCESS || rc == MEMCACHED_BUFFERED);
- }
-
- bool setAll(std::vector<std::string> &keys,
- std::vector< std::vector<char> *> &values,
- time_t expiration,
- uint32_t flags)
- {
- if (keys.size() != values.size())
- {
- return false;
- }
- bool retval= true;
- std::vector<std::string>::iterator key_it= keys.begin();
- std::vector< std::vector<char> *>::iterator val_it= values.begin();
- while (key_it != keys.end())
- {
- retval= set((*key_it), *(*val_it), expiration, flags);
- if (retval == false)
- {
- return retval;
- }
- ++key_it;
- ++val_it;
- }
- return retval;
- }
-
- bool setAll(std::map<const std::string, std::vector<char> > key_value_map,
- time_t expiration,
- uint32_t flags)
- {
- if (key_value_map.empty())
- {
- return false;
- }
- bool retval= true;
- std::map<const std::string, std::vector<char> >::iterator it=
- key_value_map.begin();
- while (it != key_value_map.end())
- {
- retval= set(it->first, it->second, expiration, flags);
- if (retval == false)
- {
- return false;
- }
- ++it;
- }
- return true;
- }
-
- bool setByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value,
- time_t expiration,
- uint32_t flags)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_set_by_key(&memc, master_key.c_str(),
- master_key.length(),
- key.c_str(), key.length(),
- &value[0], value.size(),
- expiration,
- flags);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool increment(const std::string &key, unsigned int offset, uint64_t *value)
- {
- if (key.empty())
- {
- return false;
- }
- memcached_return rc= memcached_increment(&memc, key.c_str(), key.length(),
- offset, value);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool decrement(const std::string &key, unsigned int offset, uint64_t *value)
- {
- if (key.empty())
- {
- return false;
- }
- memcached_return rc= memcached_decrement(&memc, key.c_str(),
- key.length(),
- offset, value);
- return (rc == MEMCACHED_SUCCESS);
- }
-
-
- bool add(const std::string &key, const std::vector<char> &value)
- {
- if (key.empty() || value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_add(&memc, key.c_str(), key.length(),
- &value[0], value.size(), 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool addByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_add_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool replace(const std::string &key, const std::vector<char> &value)
- {
- if (key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_replace(&memc, key.c_str(), key.length(),
- &value[0], value.size(),
- 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool replaceByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_replace_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool prepend(const std::string &key, const std::vector<char> &value)
- {
- if (key.empty() || value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_prepend(&memc, key.c_str(), key.length(),
- &value[0], value.size(), 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool prependByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_prepend_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0,
- 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool append(const std::string &key, const std::vector<char> &value)
- {
- if (key.empty() || value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_append(&memc,
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool appendByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_append_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool cas(const std::string &key,
- const std::vector<char> &value,
- uint64_t cas_arg)
- {
- if (key.empty() || value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_cas(&memc, key.c_str(), key.length(),
- &value[0], value.size(),
- 0, 0, cas_arg);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool casByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value,
- uint64_t cas_arg)
- {
- if (master_key.empty() ||
- key.empty() ||
- value.empty())
- {
- return false;
- }
- memcached_return rc= memcached_cas_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0, cas_arg);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool remove(const std::string &key)
- {
- if (key.empty())
- {
- return false;
- }
- memcached_return rc= memcached_delete(&memc, key.c_str(), key.length(), 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool removeByKey(const std::string &master_key,
- const std::string &key)
- {
- if (master_key.empty() || key.empty())
- {
- return false;
- }
- memcached_return rc= memcached_delete_by_key(&memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- 0);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool flush(time_t expiration)
- {
- memcached_return rc= memcached_flush(&memc, expiration);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- bool fetchExecute(memcached_execute_function *callback,
- void *context,
- unsigned int num_of_callbacks)
- {
- memcached_return rc= memcached_fetch_execute(&memc,
- callback,
- context,
- num_of_callbacks);
- return (rc == MEMCACHED_SUCCESS);
- }
-
- /**
- * Get the library version string.
- * @return std::string containing a copy of the library version string.
- */
- const std::string libVersion() const
- {
- const char *ver= memcached_lib_version();
- const std::string version(ver);
- return version;
- }
-
-private: