-#include <libmemcached/memcached.h>
-#include <libmemcached/exception.hpp>
-
-#include <string.h>
-
-#include <sstream>
-#include <string>
-#include <vector>
-#include <map>
-
-namespace memcache
-{
-
-/**
- * This is the core memcached library (if later, other objects
- * are needed, they will be created from this class).
- */
-class Memcache
-{
-public:
-
- Memcache()
- {
- memc= memcached("", 0);
- }
-
- Memcache(const std::string &config)
- {
- memc= memcached(config.c_str(), config.size());
- }
-
- Memcache(const std::string &hostname, in_port_t port)
- {
- memc= memcached("", 0);
- if (memc)
- memcached_server_add(memc, hostname.c_str(), port);
- }
-
- Memcache(memcached_st *clone)
- {
- memc= memcached_clone(NULL, clone);
- }
-
- Memcache(const Memcache &rhs)
- {
- memc= memcached_clone(NULL, rhs.getImpl());
- }
-
- Memcache &operator=(const Memcache &rhs)
- {
- if (this != &rhs)
- {
- memcached_free(memc);
- memc= memcached_clone(NULL, rhs.getImpl());
- }
-
- return *this;
- }
-
- ~Memcache()
- {
- memcached_free(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_t structure
- * @return error string corresponding to given return code in the library.
- */
- const std::string getError(memcached_return_t rc) const
- {
- /* first parameter to strerror is unused */
- return memcached_strerror(NULL, rc);
- }
-
- bool error(std::string& error_message) const
- {
- if (memcached_failed(memcached_last_error(memc)))
- {
- error_message+= memcached_last_error_message(memc);
- return true;
- }
-
- return false;
- }
-
- bool error() const
- {
- if (memcached_failed(memcached_last_error(memc)))
- {
- return true;
- }
-
- return false;
- }
-
- bool error(memcached_return_t& arg) const
- {
- arg= memcached_last_error(memc);
- return memcached_failed(arg);
- }
-
- bool setBehavior(memcached_behavior_t flag, uint64_t data)
- {
- return (memcached_success(memcached_behavior_set(memc, flag, data)));
- }
-
- uint64_t getBehavior(memcached_behavior_t flag)
- {
- return memcached_behavior_get(memc, flag);
- }
-
- /**
- * Configure the memcache object
- *
- * @param[in] in_config configuration
- * @return true on success; false otherwise
- */
- bool configure(const std::string &configuration)
- {
- memcached_st *new_memc= memcached(configuration.c_str(), configuration.size());
-
- if (new_memc)
- {
- memcached_free(memc);
- memc= new_memc;
-
- return true;
- }
-
- return false;
- }
-
- /**
- * Add a server to the list of memcached servers to use.
- *
- * @param[in] server_name name of the server to add
- * @param[in] port port number of server to add
- * @return true on success; false otherwise
- */
- bool addServer(const std::string &server_name, in_port_t port)
- {
- return memcached_success(memcached_server_add(memc, server_name.c_str(), port));
- }
-
- /**
- * Remove a server from the list of memcached servers to use.
- *
- * @param[in] server_name name of the server to remove
- * @param[in] port port number of server to remove
- * @return true on success; false otherwise
- */
- bool removeServer(const std::string &server_name, in_port_t port)
- {
- std::string tmp_str;
- std::ostringstream strstm;
- tmp_str.append(",");
- tmp_str.append(server_name);
- tmp_str.append(":");
- strstm << port;
- tmp_str.append(strstm.str());
-
- //memcached_return_t rc= memcached_server_remove(server);
-
- return false;
- }
-
- /**
- * Fetches an individual value from the server. mget() must always
- * be called before using this method.
- *
- * @param[in] key key of object to fetch
- * @param[out] ret_val store returned object in this vector
- * @return a memcached return structure
- */
- memcached_return_t fetch(std::string &key,
- std::vector<char> &ret_val,
- uint32_t &flags,
- uint64_t &cas_value)
- {
- memcached_return_t rc;
-
- memcached_result_st *result;
- if ((result= memcached_fetch_result(memc, NULL, &rc)))
- {
- // Key
- key.assign(memcached_result_key_value(result), memcached_result_key_length(result));
-
- // Actual value, null terminated
- ret_val.reserve(memcached_result_length(result) +1);
- ret_val.assign(memcached_result_value(result),
- memcached_result_value(result) +memcached_result_length(result));
-
- // Misc
- flags= memcached_result_flags(result);
- cas_value= memcached_result_cas(result);
- }
- memcached_result_free(result);
-
- return rc;
- }
-
- memcached_return_t fetch(std::string &key,
- std::vector<char> &ret_val)
- {
- uint32_t flags= 0;
- uint64_t cas_value= 0;
-
- return fetch(key, ret_val, flags, cas_value);
- }
-
- /**
- * Fetches an individual value from the server.
- *
- * @param[in] key key of object whose value to get
- * @param[out] ret_val object that is retrieved is stored in
- * this vector
- * @return true on success; false otherwise
- */
- bool get(const std::string &key, std::vector<char> &ret_val)
- {
- uint32_t flags= 0;
- memcached_return_t rc;
- size_t value_length= 0;
-
- 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);
- free(value);
- return true;
- }
-
- return false;
- }
-
- /**
- * Fetches an individual from a server which is specified by
- * the master_key parameter that is used for determining which
- * server an object was stored in if key partitioning was
- * used for storage.
- *
- * @param[in] master_key key that specifies server object is stored on
- * @param[in] key key of object whose value to get
- * @param[out] ret_val object that is retrieved is stored in
- * this vector
- * @return true on success; false otherwise
- */
- bool getByKey(const std::string &master_key,
- const std::string &key,
- std::vector<char> &ret_val)
- {
- uint32_t flags= 0;
- memcached_return_t rc;
- size_t value_length= 0;
-
- 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);
- free(value);
- return true;
- }
- return false;
- }
-
- /**
- * Selects multiple keys at once. This method always
- * works asynchronously.
- *
- * @param[in] keys vector of keys to select
- * @return true if all keys are found
- */
- 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 (not real_keys.empty())
- {
- return memcached_success(memcached_mget(memc, &real_keys[0], &key_len[0], real_keys.size()));
- }
-
- return false;
- }
-
- /**
- * Writes an object to the server. If the object already exists, it will
- * overwrite the existing object. This method always returns true
- * when using non-blocking mode unless a network error occurs.
- *
- * @param[in] key key of object to write to server
- * @param[in] value value of object to write to server
- * @param[in] expiration time to keep the object stored in the server for
- * @param[in] flags flags to store with the object
- * @return true on succcess; false otherwise
- */
- bool set(const std::string &key,
- const std::vector<char> &value,
- time_t expiration,
- uint32_t flags)
- {
- memcached_return_t rc= memcached_set(memc,
- key.c_str(), key.length(),
- &value[0], value.size(),
- expiration, flags);
- return memcached_success(rc);
- }
-
- /**
- * Writes an object to a server specified by the master_key parameter.
- * If the object already exists, it will overwrite the existing object.
- *
- * @param[in] master_key key that specifies server to write to
- * @param[in] key key of object to write to server
- * @param[in] value value of object to write to server
- * @param[in] expiration time to keep the object stored in the server for
- * @param[in] flags flags to store with the object
- * @return true on succcess; false otherwise
- */
- bool setByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value,
- time_t expiration,
- uint32_t flags)
- {
- return memcached_success(memcached_set_by_key(memc, master_key.c_str(),
- master_key.length(),
- key.c_str(), key.length(),
- &value[0], value.size(),
- expiration,
- flags));
- }
-
- /**
- * Writes a list of objects to the server. Objects are specified by
- * 2 vectors - 1 vector of keys and 1 vector of values.
- *
- * @param[in] keys vector of keys of objects to write to server
- * @param[in] values vector of values of objects to write to server
- * @param[in] expiration time to keep the objects stored in server for
- * @param[in] flags flags to store with the objects
- * @return true on success; false otherwise
- */
- bool setAll(std::vector<std::string> &keys,
- std::vector< std::vector<char> *> &values,
- time_t expiration,
- uint32_t flags)
- {
- 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;
- }
-
- /**
- * Writes a list of objects to the server. Objects are specified by
- * a map of keys to values.
- *
- * @param[in] key_value_map map of keys and values to store in server
- * @param[in] expiration time to keep the objects stored in server for
- * @param[in] flags flags to store with the objects
- * @return true on success; false otherwise
- */
- bool setAll(std::map<const std::string, std::vector<char> > &key_value_map,
- time_t expiration,
- uint32_t flags)
- {
- 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)
- {
- // We should tell the user what the key that failed was
- return false;
- }
- ++it;
- }
- return true;
- }
-
- /**
- * Increment the value of the object associated with the specified
- * key by the offset given. The resulting value is saved in the value
- * parameter.
- *
- * @param[in] key key of object in server whose value to increment
- * @param[in] offset amount to increment object's value by
- * @param[out] value store the result of the increment here
- * @return true on success; false otherwise
- */
- bool increment(const std::string &key, uint32_t offset, uint64_t *value)
- {
- return memcached_success(memcached_increment(memc, key.c_str(), key.length(), offset, value));
- }
-
- /**
- * Decrement the value of the object associated with the specified
- * key by the offset given. The resulting value is saved in the value
- * parameter.
- *
- * @param[in] key key of object in server whose value to decrement
- * @param[in] offset amount to increment object's value by
- * @param[out] value store the result of the decrement here
- * @return true on success; false otherwise
- */
- bool decrement(const std::string &key, uint32_t offset, uint64_t *value)
- {
- return memcached_success(memcached_decrement(memc, key.c_str(),
- key.length(),
- offset, value));
- }
-
-
- /**
- * Add an object with the specified key and value to the server. This
- * function returns false if the object already exists on the server.
- *
- * @param[in] key key of object to add
- * @param[in] value of object to add
- * @return true on success; false otherwise
- */
- bool add(const std::string &key, const std::vector<char> &value)
- {
- return memcached_success(memcached_add(memc, key.c_str(), key.length(),
- &value[0], value.size(), 0, 0));
- }
-
- /**
- * Add an object with the specified key and value to the server. This
- * function returns false if the object already exists on the server. The
- * server to add the object to is specified by the master_key parameter.
- *
- * @param[in[ master_key key of server to add object to
- * @param[in] key key of object to add
- * @param[in] value of object to add
- * @return true on success; false otherwise
- */
- bool addByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- return memcached_success(memcached_add_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0));
- }
-
- /**
- * Replaces an object on the server. This method only succeeds
- * if the object is already present on the server.
- *
- * @param[in] key key of object to replace
- * @param[in[ value value to replace object with
- * @return true on success; false otherwise
- */
- bool replace(const std::string &key, const std::vector<char> &value)
- {
- return memcached_success(memcached_replace(memc, key.c_str(), key.length(),
- &value[0], value.size(),
- 0, 0));
- }
-
- /**
- * Replaces an object on the server. This method only succeeds
- * if the object is already present on the server. The server
- * to replace the object on is specified by the master_key param.
- *
- * @param[in] master_key key of server to replace object on
- * @param[in] key key of object to replace
- * @param[in[ value value to replace object with
- * @return true on success; false otherwise
- */
- bool replaceByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- return memcached_success(memcached_replace_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0));
- }
-
- /**
- * Places a segment of data before the last piece of data stored.
- *
- * @param[in] key key of object whose value we will prepend data to
- * @param[in] value data to prepend to object's value
- * @return true on success; false otherwise
- */
- bool prepend(const std::string &key, const std::vector<char> &value)
- {
- return memcached_success(memcached_prepend(memc, key.c_str(), key.length(),
- &value[0], value.size(), 0, 0));
- }
-
- /**
- * Places a segment of data before the last piece of data stored. The
- * server on which the object where we will be prepending data is stored
- * on is specified by the master_key parameter.
- *
- * @param[in] master_key key of server where object is stored
- * @param[in] key key of object whose value we will prepend data to
- * @param[in] value data to prepend to object's value
- * @return true on success; false otherwise
- */
- bool prependByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- return memcached_success(memcached_prepend_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0,
- 0));
- }
-
- /**
- * Places a segment of data at the end of the last piece of data stored.
- *
- * @param[in] key key of object whose value we will append data to
- * @param[in] value data to append to object's value
- * @return true on success; false otherwise
- */
- bool append(const std::string &key, const std::vector<char> &value)
- {
- return memcached_success(memcached_append(memc,
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0));
- }
-
- /**
- * Places a segment of data at the end of the last piece of data stored. The
- * server on which the object where we will be appending data is stored
- * on is specified by the master_key parameter.
- *
- * @param[in] master_key key of server where object is stored
- * @param[in] key key of object whose value we will append data to
- * @param[in] value data to append to object's value
- * @return true on success; false otherwise
- */
- bool appendByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value)
- {
- return memcached_success(memcached_append_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- &value[0],
- value.size(),
- 0, 0));
- }
-
- /**
- * Overwrite data in the server as long as the cas_arg value
- * is still the same in the server.
- *
- * @param[in] key key of object in server
- * @param[in] value value to store for object in server
- * @param[in] cas_arg "cas" value
- */
- bool cas(const std::string &key,
- const std::vector<char> &value,
- uint64_t cas_arg)
- {
- return memcached_success(memcached_cas(memc, key.c_str(), key.length(),
- &value[0], value.size(),
- 0, 0, cas_arg));
- }
-
- /**
- * Overwrite data in the server as long as the cas_arg value
- * is still the same in the server. The server to use is
- * specified by the master_key parameter.
- *
- * @param[in] master_key specifies server to operate on
- * @param[in] key key of object in server
- * @param[in] value value to store for object in server
- * @param[in] cas_arg "cas" value
- */
- bool casByKey(const std::string &master_key,
- const std::string &key,
- const std::vector<char> &value,
- uint64_t cas_arg)
- {
- return memcached_success(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));
- }
-
- /**
- * Delete an object from the server specified by the key given.
- *
- * @param[in] key key of object to delete
- * @return true on success; false otherwise
- */
- bool remove(const std::string &key)
- {
- return memcached_success(memcached_delete(memc, key.c_str(), key.length(), 0));
- }
-
- /**
- * Delete an object from the server specified by the key given.
- *
- * @param[in] key key of object to delete
- * @param[in] expiration time to delete the object after
- * @return true on success; false otherwise
- */
- bool remove(const std::string &key, time_t expiration)
- {
- return memcached_success(memcached_delete(memc,
- key.c_str(),
- key.length(),
- expiration));
- }
-
- /**
- * Delete an object from the server specified by the key given.
- *
- * @param[in] master_key specifies server to remove object from
- * @param[in] key key of object to delete
- * @return true on success; false otherwise
- */
- bool removeByKey(const std::string &master_key,
- const std::string &key)
- {
- return memcached_success(memcached_delete_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- 0));
- }
-
- /**
- * Delete an object from the server specified by the key given.
- *
- * @param[in] master_key specifies server to remove object from
- * @param[in] key key of object to delete
- * @param[in] expiration time to delete the object after
- * @return true on success; false otherwise
- */
- bool removeByKey(const std::string &master_key,
- const std::string &key,
- time_t expiration)
- {
- return memcached_success(memcached_delete_by_key(memc,
- master_key.c_str(),
- master_key.length(),
- key.c_str(),
- key.length(),
- expiration));
- }
-
- /**
- * Wipe the contents of memcached servers.
- *
- * @param[in] expiration time to wait until wiping contents of
- * memcached servers
- * @return true on success; false otherwise
- */
- bool flush(time_t expiration= 0)
- {
- return memcached_success(memcached_flush(memc, expiration));
- }
-
- /**
- * 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;
- }
-
- /**
- * Retrieve memcached statistics. Populate a std::map with the retrieved
- * stats. Each server will map to another std::map of the key:value stats.
- *
- * @param[out] stats_map a std::map to be populated with the memcached
- * stats
- * @return true on success; false otherwise
- */
- bool getStats(std::map< std::string, std::map<std::string, std::string> >
- &stats_map)
- {
- memcached_return_t rc;
- memcached_stat_st *stats= memcached_stat(memc, NULL, &rc);
-
- if (rc != MEMCACHED_SUCCESS &&
- rc != MEMCACHED_SOME_ERRORS)
- {
- return false;
- }
-
- uint32_t server_count= memcached_server_count(memc);
-
- /*
- * For each memcached server, construct a std::map for its stats and add
- * it to the std::map of overall stats.
- */
- for (uint32_t x= 0; x < server_count; x++)
- {
- memcached_server_instance_st instance=
- memcached_server_instance_by_position(memc, x);
- std::ostringstream strstm;
- std::string server_name(memcached_server_name(instance));
- server_name.append(":");
- strstm << memcached_server_port(instance);
- server_name.append(strstm.str());
-
- std::map<std::string, std::string> server_stats;
- char **list= NULL;
- char **ptr= NULL;
-
- list= memcached_stat_get_keys(memc, &stats[x], &rc);
- for (ptr= list; *ptr; ptr++)
- {
- char *value= memcached_stat_get_value(memc, &stats[x], *ptr, &rc);
- server_stats[*ptr]= value;
- free(value);
- }
-
- stats_map[server_name]= server_stats;
- free(list);
- }
-
- memcached_stat_free(memc, stats);
- return true;
- }
-
-private:
- memcached_st *memc;
-};