nextcloud-desktop/sqlite3_util.cpp
Juan Carlos Cornejo 2c3373d7d9 Contacted the author of the sqlite3_util.cpp function and found out
it was placed in the public domain. Made the changes to the header
and cpp file to reflect that.

Also renamed LICENSE to COPYING-GPL and made not of the overall
project license in COPYING
2012-02-15 08:55:13 +01:00

90 lines
4.3 KiB
C++

/******************************************************************************
* This function was copied from:
* http://www.qtcentre.org/threads/36131-Attempting-to-use-Sqlite-backup-api-from-driver-handle-fails?p=207558#post207558
* on November 10, 2011. The function has been released to the Public Domain
* by its deveveloper.
*
*******************************************************************************/
#include "sqlite3_util.h"
#include <sqlite3.h>
#include <QVariant>
#include <QSqlDriver>
/*
** This function is used to load the contents of a database file on disk
** into the "main" database of open database connection pInMemory, or
** to save the current contents of the database opened by pInMemory into
** a database file on disk. pInMemory is probably an in-memory database,
** but this function will also work fine if it is not.
**
** Parameter zFilename points to a nul-terminated string containing the
** name of the database file on disk to load from or save to. If parameter
** isSave is non-zero, then the contents of the file zFilename are
** overwritten with the contents of the database opened by pInMemory. If
** parameter isSave is zero, then the contents of the database opened by
** pInMemory are replaced by data loaded from the file zFilename.
**
** If the operation is successful, SQLITE_OK is returned. Otherwise, if
** an error occurs, an SQLite error code is returned.
*/
bool sqlite3_util::sqliteDBMemFile( QSqlDatabase memdb, QString filename, bool save )
{
bool state = false;
QVariant v = memdb.driver()->handle();
if( v.isValid() && qstrcmp(v.typeName(),"sqlite3*") == 0 )
{
// v.data() returns a pointer to the handle
sqlite3 * handle = *static_cast<sqlite3 **>(v.data());
if( handle != 0 ) // check that it is not NULL
{
sqlite3 * pInMemory = handle;
QByteArray array = filename.toLocal8Bit();
const char * zFilename = array.data();
int rc; /* Function return code */
sqlite3 *pFile; /* Database connection opened on zFilename */
sqlite3_backup *pBackup; /* Backup object used to copy data */
sqlite3 *pTo; /* Database to copy to (pFile or pInMemory) */
sqlite3 *pFrom; /* Database to copy from (pFile or pInMemory) */
/* Open the database file identified by zFilename. Exit early if this fails
** for any reason. */
rc = sqlite3_open( zFilename, &pFile );
if( rc==SQLITE_OK ){
/* If this is a 'load' operation (isSave==0), then data is copied
** from the database file just opened to database pInMemory.
** Otherwise, if this is a 'save' operation (isSave==1), then data
** is copied from pInMemory to pFile. Set the variables pFrom and
** pTo accordingly. */
pFrom = ( save ? pInMemory : pFile);
pTo = ( save ? pFile : pInMemory);
/* Set up the backup procedure to copy from the "main" database of
** connection pFile to the main database of connection pInMemory.
** If something goes wrong, pBackup will be set to NULL and an error
** code and message left in connection pTo.
**
** If the backup object is successfully created, call backup_step()
** to copy data from pFile to pInMemory. Then call backup_finish()
** to release resources associated with the pBackup object. If an
** error occurred, then an error code and message will be left in
** connection pTo. If no error occurred, then the error code belonging
** to pTo is set to SQLITE_OK.
*/
pBackup = sqlite3_backup_init(pTo, "main", pFrom, "main");
if( pBackup ){
(void)sqlite3_backup_step(pBackup, -1);
(void)sqlite3_backup_finish(pBackup);
}
rc = sqlite3_errcode(pTo);
}
/* Close the database connection opened on database file zFilename
** and return the result of this function. */
(void)sqlite3_close(pFile);
if( rc == SQLITE_OK ) state = true;
}
}
return state;
}