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Database Class Reference Connection information and pooling. More... #include <Database.h> Collaboration diagram for Database: List of all members. Public Types typedef std::list< OPENDB * >  opendb_v Public Member Functions   Database (const std::string &database, IError *=NULL)   Use embedded libmysqld.   Database (Mutex &, const std::string &database, IError *=NULL)   Use embedded libmysqld + thread safe.   Database (const std::string &host, const std::string &user, const std::string &password="", const std::string &database="", IError *=NULL)   Connect to a MySQL server.   Database (Mutex &, const std::string &host, const std::string &user, const std::string &password="", const std::string &database="", IError *=NULL)   Connect to a MySQL server + thread safe. virtual  ~Database () virtual void  OnMyInit (OPENDB *)   Callback after mysql_init. bool  Connected ()   try to establish connection with given host void  RegErrHandler (IError *) void  error (Query &, const char *format,...) OPENDB *  grabdb ()   Request a database connection. void  freedb (OPENDB *odb) std::string  safestr (const std::string &) std::string  unsafestr (const std::string &) std::string  xmlsafestr (const std::string &) int64_t  a2bigint (const std::string &) uint64_t  a2ubigint (const std::string &) Private Member Functions   Database (const Database &) Database &  operator= (const Database &) void  error (const char *format,...) Private Attributes std::string  host std::string  user std::string  password std::string  database opendb_v  m_opendbs IError *  m_errhandler bool  m_embedded Mutex &  m_mutex bool  m_b_use_mutex Classes class   Lock   Mutex helper class. More... class   Mutex   Mutex container class, used by Lock. More... struct   OPENDB   Connection pool struct. More... Detailed Description Connection information and pooling. Definition at line 60 of file Database.h. Member Typedef Documentation typedef std::list<OPENDB *> Database::opendb_v Definition at line 95 of file Database.h. Constructor & Destructor Documentation Database::Database ( const std::string &  d, IError *  e = NULL   ) Use embedded libmysqld. Published / author: 2001-02-15 / grymse@alhem.net Definition at line 59 of file Database.cpp. :database(d) ,m_errhandler(e) ,m_embedded(true) ,m_mutex(m_mutex) ,m_b_use_mutex(false) { } Database::Database ( Mutex &  , const std::string &  database, IError *  = NULL   ) Use embedded libmysqld + thread safe. Definition at line 69 of file Database.cpp. :database(d) ,m_errhandler(e) ,m_embedded(true) ,m_mutex(m) ,m_b_use_mutex(true) { } Database::Database ( const std::string &  host, const std::string &  user, const std::string &  password = "", const std::string &  database = "", IError *  = NULL   ) Connect to a MySQL server. Definition at line 79 of file Database.cpp. :host(h) ,user(u) ,password(p) ,database(d) ,m_errhandler(e) ,m_embedded(false) ,m_mutex(m_mutex) ,m_b_use_mutex(false) { } Database::Database ( Mutex &  , const std::string &  host, const std::string &  user, const std::string &  password = "", const std::string &  database = "", IError *  = NULL   ) Connect to a MySQL server + thread safe. Definition at line 92 of file Database.cpp. :host(h) ,user(u) ,password(p) ,database(d) ,m_errhandler(e) ,m_embedded(false) ,m_mutex(m) ,m_b_use_mutex(true) { } Database::~Database (  )  [virtual] Definition at line 105 of file Database.cpp. References error(), and m_opendbs. { for (opendb_v::iterator it = m_opendbs.begin(); it != m_opendbs.end(); it++) { OPENDB *p = *it; mysql_close(&p -> mysql); } while (m_opendbs.size()) { opendb_v::iterator it = m_opendbs.begin(); OPENDB *p = *it; if (p -> busy) { error("destroying Database object before Query object"); } delete p; m_opendbs.erase(it); } } Database::Database ( const Database &   )  [inline, private] Definition at line 158 of file Database.h. : m_mutex(m_mutex) {} Member Function Documentation void Database::OnMyInit ( OPENDB *   )  [virtual] Callback after mysql_init. Definition at line 126 of file Database.cpp. References m_embedded. Referenced by grabdb(). { // using embedded server (libmysqld) if (m_embedded) { mysql_options(&odb -> mysql, MYSQL_READ_DEFAULT_GROUP, "test_libmysqld_CLIENT"); } } bool Database::Connected (  )  try to establish connection with given host Definition at line 254 of file Database.cpp. References error(), freedb(), and grabdb(). { OPENDB *odb = grabdb(); if (!odb) { return false; } int ping_result = mysql_ping(&odb -> mysql); if (ping_result) { error("mysql_ping() failed"); } freedb(odb); return ping_result ? false : true; } void Database::RegErrHandler ( IError *   )  Definition at line 136 of file Database.cpp. References m_errhandler. { m_errhandler = p; } void Database::error ( Query &  , const char *  format,   ...   ) Definition at line 236 of file Database.cpp. References m_errhandler. Referenced by Query::Connected(), Connected(), Query::error(), error(), Query::execute(), Query::get_result(), grabdb(), ~Database(), and Query::~Query(). { if (m_errhandler) { va_list ap; char errstr[5000]; va_start(ap, format); #ifdef WIN32 vsprintf(errstr, format, ap); #else vsnprintf(errstr, 5000, format, ap); #endif va_end(ap); m_errhandler -> error(*this, q, errstr); } } Database::OPENDB * Database::grabdb (  )  Request a database connection. The "grabdb" method is used by the Query class, so that each object instance of Query gets a unique database connection. I will reimplement your connection check logic in the Query class, as that's where the database connection is really used. It should be used something like this. { Query q(db); if (!q.Connected()) return false; q.execute("delete * from user"); // well maybe not } When the Query object is deleted, then "freedb" is called - the database connection stays open in the m_opendbs vector. New Query objects can then reuse old connections. Definition at line 142 of file Database.cpp. References database, error(), host, m_b_use_mutex, m_embedded, m_mutex, m_opendbs, OnMyInit(), password, and user. Referenced by Connected(). { Lock lck(m_mutex, m_b_use_mutex); OPENDB *odb = NULL; for (opendb_v::iterator it = m_opendbs.begin(); it != m_opendbs.end(); it++) { odb = *it; if (!odb -> busy) { break; } else { odb = NULL; } } if (!odb) { odb = new OPENDB; if (!odb) { error("grabdb: OPENDB struct couldn't be created"); return NULL; } if (!mysql_init(&odb -> mysql)) { error("mysql_init() failed - list size %d",m_opendbs.size()); delete odb; return NULL; } // use callback to set mysql_options() before connect, etc this -> OnMyInit(odb); if (m_embedded) { if (!mysql_real_connect(&odb -> mysql,NULL,NULL,NULL,database.c_str(),0,NULL,0) ) { error("mysql_real_connect(NULL,NULL,NULL,%s,0,NULL,0) failed - list size %d",database.c_str(),m_opendbs.size()); delete odb; return NULL; } } else { if (!mysql_real_connect(&odb -> mysql,host.c_str(),user.c_str(),password.c_str(),database.c_str(),0,NULL,0) ) { error("mysql_real_connect(%s,%s,***,%s,0,NULL,0) failed - list size %d",host.c_str(),user.c_str(),database.c_str(),m_opendbs.size()); delete odb; return NULL; } } odb -> busy = true; m_opendbs.push_back(odb); } else { if (mysql_ping(&odb -> mysql)) { error("mysql_ping() failed when reusing an old connection from the connection pool"); } odb -> busy = true; } return odb; } void Database::freedb ( OPENDB *  odb  )  Definition at line 208 of file Database.cpp. References m_b_use_mutex, and m_mutex. Referenced by Connected(), and Query::~Query(). { Lock lck(m_mutex, m_b_use_mutex); if (odb) { odb -> busy = false; } } std::string Database::safestr ( const std::string &   )  Definition at line 330 of file Database.cpp. Referenced by Query::safestr(). { std::string str2; for (size_t i = 0; i < str.size(); i++) { switch (str[i]) { case '\'': case '\\': case 34: str2 += '\\'; default: str2 += str[i]; } } return str2; } std::string Database::unsafestr ( const std::string &   )  Definition at line 349 of file Database.cpp. { std::string str2; for (size_t i = 0; i < str.size(); i++) { if (str[i] == '\\') { i++; } if (i < str.size()) { str2 += str[i]; } } return str2; } std::string Database::xmlsafestr ( const std::string &   )  Definition at line 367 of file Database.cpp. { std::string str2; for (size_t i = 0; i < str.size(); i++) { switch (str[i]) { case '&': str2 += "&amp;"; break; case '<': str2 += "&lt;"; break; case '>': str2 += "&gt;"; break; case '"': str2 += "&quot;"; break; case '\'': str2 += "&apos;"; break; default: str2 += str[i]; } } return str2; } int64_t Database::a2bigint ( const std::string &   )  Definition at line 397 of file Database.cpp. Referenced by Query::getbigint(). { int64_t val = 0; bool sign = false; size_t i = 0; if (str[i] == '-') { sign = true; i++; } for (; i < str.size(); i++) { val = val * 10 + (str[i] - 48); } return sign ? -val : val; } uint64_t Database::a2ubigint ( const std::string &   )  Definition at line 415 of file Database.cpp. Referenced by Query::getubigint(), and Query::getuval(). { uint64_t val = 0; for (size_t i = 0; i < str.size(); i++) { val = val * 10 + (str[i] - 48); } return val; } Database& Database::operator= ( const Database &   )  [inline, private] Definition at line 159 of file Database.h. { return *this; } void Database::error ( const char *  format,   ...   ) [private] Definition at line 218 of file Database.cpp. References error(), and m_errhandler. { if (m_errhandler) { va_list ap; char errstr[5000]; va_start(ap, format); #ifdef WIN32 vsprintf(errstr, format, ap); #else vsnprintf(errstr, 5000, format, ap); #endif va_end(ap); m_errhandler -> error(*this, errstr); } } Member Data Documentation std::string Database::host [private] Definition at line 162 of file Database.h. Referenced by grabdb(). std::string Database::user [private] Definition at line 163 of file Database.h. Referenced by grabdb(). std::string Database::password [private] Definition at line 164 of file Database.h. Referenced by grabdb(). std::string Database::database [private] Definition at line 165 of file Database.h. Referenced by grabdb(). opendb_v Database::m_opendbs [private] Definition at line 166 of file Database.h. Referenced by grabdb(), and ~Database(). IError* Database::m_errhandler [private] Definition at line 167 of file Database.h. Referenced by error(), and RegErrHandler(). bool Database::m_embedded [private] Definition at line 168 of file Database.h. Referenced by grabdb(), and OnMyInit(). Mutex& Database::m_mutex [private] Definition at line 169 of file Database.h. Referenced by freedb(), and grabdb(). bool Database::m_b_use_mutex [private] Definition at line 170 of file Database.h. Referenced by freedb(), and grabdb(). The documentation for this class was generated from the following files: Database.h Database.cpp

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