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Database Class Reference Connection information and pool. 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 file.   Database (Mutex &, const std::string &database, IError *=NULL)   Use file + thread safe. virtual  ~Database () bool  Connected ()   try to establish connection with given host void  RegErrHandler (IError *) void  error (Query &, const char *format,...) void  error (Query &, const std::string &) OPENDB *  grabdb ()   Request a database connection. void  freedb (OPENDB *odb) std::string  safestr (const std::string &)   Escape string - change all ' to ''. std::string  xmlsafestr (const std::string &)   Make string xml safe. int64_t  a2bigint (const std::string &)   Convert string to 64-bit integer. uint64_t  a2ubigint (const std::string &)   Convert string to unsigned 64-bit integer. Private Member Functions   Database (const Database &) Database &  operator= (const Database &) void  error (const char *format,...) Private Attributes 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 pool. Definition at line 61 of file Database.h. Member Typedef Documentation typedef std::list<OPENDB *> Database::opendb_v Definition at line 96 of file Database.h. Constructor & Destructor Documentation Database::Database ( const std::string &  database, IError *  = NULL   ) Use file. Definition at line 54 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 file + thread safe. Definition at line 64 of file Database.cpp. :database(d) ,m_errhandler(e) ,m_embedded(true) ,m_mutex(m) ,m_b_use_mutex(true) { } Database::~Database (  )  [virtual] Definition at line 74 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; sqlite3_close(p -> db); } 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 145 of file Database.h. : m_mutex(m_mutex) {} Member Function Documentation bool Database::Connected (  )  try to establish connection with given host Definition at line 200 of file Database.cpp. References freedb(), and grabdb(). { OPENDB *odb = grabdb(); if (!odb) { return false; } freedb(odb); return true; } void Database::RegErrHandler ( IError *   )  Definition at line 95 of file Database.cpp. References m_errhandler. { m_errhandler = p; } void Database::error ( Query &  , const char *  format,   ...   ) Definition at line 173 of file Database.cpp. References m_errhandler. Referenced by Query::error(), error(), Query::execute(), Query::fetch_row(), 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); } } void Database::error ( Query &  , const std::string &    ) Definition at line 191 of file Database.cpp. References error(), and m_errhandler. { if (m_errhandler) { m_errhandler -> error(*this, q, msg); } } 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 101 of file Database.cpp. References database, error(), m_b_use_mutex, m_mutex, and m_opendbs. 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; } int rc = sqlite3_open(database.c_str(), &odb -> db); if (rc) { error("Can't open database: %s\n", sqlite3_errmsg(odb -> db)); sqlite3_close(odb -> db); delete odb; return NULL; } odb -> busy = true; m_opendbs.push_back(odb); } else { odb -> busy = true; } return odb; } void Database::freedb ( OPENDB *  odb  )  Definition at line 145 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 &   )  Escape string - change all ' to ''. Definition at line 271 of file Database.cpp. { 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::xmlsafestr ( const std::string &   )  Make string xml safe. Definition at line 290 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 &   )  Convert string to 64-bit integer. Definition at line 320 of file Database.cpp. { 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 &   )  Convert string to unsigned 64-bit integer. Definition at line 338 of file Database.cpp. { 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 146 of file Database.h. { return *this; } void Database::error ( const char *  format,   ...   ) [private] Definition at line 155 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::database [private] Definition at line 149 of file Database.h. Referenced by grabdb(). opendb_v Database::m_opendbs [private] Definition at line 150 of file Database.h. Referenced by grabdb(), and ~Database(). IError* Database::m_errhandler [private] Definition at line 151 of file Database.h. Referenced by error(), and RegErrHandler(). bool Database::m_embedded [private] Definition at line 152 of file Database.h. Mutex& Database::m_mutex [private] Definition at line 153 of file Database.h. Referenced by freedb(), and grabdb(). bool Database::m_b_use_mutex [private] Definition at line 154 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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