GeezerVison is showing github.com — livecode/revdb/src/sqlite_cursor.cpp at develop · livecode/livecode

This repository was archived by the owner on Aug 31, 2021. It is now read-only.

Expand file tree

sqlite_cursor.cpp

Copy path

More file actions

Latest commit

History

401 lines (328 loc) · 8.89 KB

sqlite_cursor.cpp

Copy path

File metadata and controls

401 lines (328 loc) · 8.89 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

This file is part of LiveCode.

LiveCode is free software; you can redistribute it and/or modify it under

the terms of the GNU General Public License v3 as published by the Free

Software Foundation.

LiveCode is distributed in the hope that it will be useful, but WITHOUT ANY

WARRANTY; without even the implied warranty of MERCHANTABILITY or

FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License

for more details.

You should have received a copy of the GNU General Public License

along with LiveCode. If not see <http://www.gnu.org/licenses/>. */

/*DBCURSOR_SQLITE - CUSROR OBJECT FOR MYSQL DATABASES CHILD OF DBCURSOR

Attributes:

mysql_res - result set structure for MYSQL database

isBOF - True if at beginning of resultset (inherited)

isEOF - True if at end of resultset (inherited)

recordNum - Number of current record -1 (inherited)

recordCount - Number of records in resultset (inherited)

fieldCount - Number of columns (inherited)

fields - Array of fields (inherited)

connection - Pointer to dbconnection_mysql object that created cursor

Methods:

Open - opens cursor and retrieves resultset from connection

Close - closes cursor and frees any resources used by cursor

getFieldsInformation - get column names, types, and info

getRowData - Retrieve the data from the current row.

first - move to first row of resultset

next - move to next row of resultset

prev - move to previous row of resultset

last - move to last row of resultset

#include "dbsqlite.h"

#include <sqlitedecode.h>

#define ENTER

DBCursor_SQLITE::DBCursor_SQLITE(SqliteDatabase &db, bool enable_binary)

: mDB(db)

{

ENTER;

mDataset = mDB.CreateDataset();

m_enable_binary = enable_binary;

}

DBCursor_SQLITE::~DBCursor_SQLITE()

{

ENTER;

close();

delete mDataset;

}

/*Open - opens cursor and retrieves resultset from connection

Output: False on error*/

Bool DBCursor_SQLITE::open(DBConnection *newconnection)

{

ENTER;

if (!newconnection->getIsConnected())

return False;

connection = newconnection;

try

{

recordCount = mDataset -> num_rows();

fieldCount = mDataset -> field_count();

if(!getFieldsInformation())

return False;

if(recordCount != 0)

first();

} catch(DbErrors &e)

{

MDEBUG("***** Caught error [%s]\n", e.getMsg());

return False;

}

MDEBUG0("Cursor::open OK\n");

return True;

}

//Close - close cursor and free resources used by cursor

void DBCursor_SQLITE::close()

{

ENTER;

MDEBUG0("\n--\n");

FreeFields();

isBOF = False;

isEOF = True;

recordNum = recordCount = fieldCount = 0;

MDEBUG0("\nBye cursor\n");

}

/*first - move to first row of resultset

Output - False on error*/

Bool DBCursor_SQLITE::first()

{

ENTER;

try {

//exit if no more records

if (recordCount == 0)

return False;

recordNum = 0;

mDataset->first();

if(!getRowData())

return False;

isBOF = True;

isEOF = False;

} catch(DbErrors &e) {

MDEBUG("***** Caught error [%s]\n", e.getMsg());

return False;

}

return True;

}

/*last - move to last row of resultset

Output - False on error*/

Bool DBCursor_SQLITE::last()

{

ENTER;

try {

if (recordCount == 0)

return False;

recordNum = recordCount-1;

mDataset->last();

if (!getRowData())

return False;

isBOF = False;

isEOF = True;

} catch(DbErrors &e) {

MDEBUG("***** Caught error [%s]\n", e.getMsg());

return False;

}

return True;

}

/*next - move to next row of resultset

Output - False on error*/

Bool DBCursor_SQLITE::next()

{

ENTER;

try {

//exit if at last record or there are no records

if (recordCount == 0 || isEOF == True)

return False;

isBOF = False;

recordNum++;

if (recordNum == recordCount) {

isEOF = true;

recordNum = recordCount-1;

return False;

}

mDataset->next();

getRowData();

} catch(DbErrors &e) {

MDEBUG("***** Caught error [%s]\n", e.getMsg());

return False;

}

return True;

}

/*prev - move to first row of resultset

Output - False on error*/

Bool DBCursor_SQLITE::prev()

{

ENTER;

try {

if (recordCount == 0)

return False;

if (isBOF)

return False;

isEOF = false;

recordNum--;

if (recordNum == -1) {

isBOF =True;

recordNum = 0;

return False;

}

mDataset->prev();

getRowData();

} catch(DbErrors &e) {

MDEBUG("***** Caught error [%s]\n", e.getMsg());

return False;

}

return True;

}

Bool DBCursor_SQLITE::move(int p_record_index)

{

if (recordCount == 0)

return False;

if (p_record_index < 0)

return False;

else if (p_record_index > recordCount - 1)

return False;

isBOF = False;

isEOF = False;

if (!mDataset -> seek(p_record_index))

return False;

recordNum = p_record_index;

getRowData();

return True;

}

/*getFieldsInformation - get column names, types, and info

Output: False on error*/

Bool DBCursor_SQLITE::getFieldsInformation()

{

ENTER;

//create an array of columns

fields = new (nothrow) DBField *[fieldCount];

Fields *t_fields_object;

t_fields_object = mDataset -> get_fields_object();

for(int i = 0 ; i < fieldCount; i++) {

DBField *tfield = new (nothrow) DBField();

fields[i] = tfield;

const char *name = mDataset->fieldName(i);

if(name) {

MDEBUG("Field name=[%s]\n", name);

const field_value fv = mDataset->get_field_value_by_index(i);

// OK-2008-10-29 : [[Bug 6588]] - Get the field type from the props structure instead of from the field value,

// because we are returning the declared column type rather than the actual type of the data in the column.

field_prop t_props;

t_props = (*t_fields_object)[i].props;

fType type;

type = t_props . type;

///////////////////

// TYPE

if (strlen(name) > F_NAMESIZE -6)

strncpy(tfield->fieldName, name, F_NAMESIZE-6);

else

strcpy(tfield->fieldName, name);

switch(type) {

case ft_Short :

case ft_UShort :

MDEBUG0("Type: smallint\n");

tfield->fieldType = FT_SMALLINT;

break;

case ft_Long :

case ft_ULong :

MDEBUG0("Type: integer\n");

tfield->fieldType = FT_INTEGER;

break;

case ft_Float:

MDEBUG0("Type: float\n");

tfield->fieldType = FT_FLOAT;

break;

case ft_Double:

case ft_LongDouble:

MDEBUG0("Type: double\n");

tfield->fieldType = FT_DOUBLE;

break;

case ft_Object :

if (m_enable_binary)

tfield -> fieldType = FT_BLOB;

else

tfield -> fieldType = FT_STRING;

break;

case ft_String :

default:

MDEBUG0("Type: string\n");

tfield->fieldType = FT_STRING;

break;

}

//get field number

tfield->fieldNum = i+1;

//get max length

tfield->maxlength = MAX_BYTES_PER_ROW;

//TODO: get column characteristics

tfield->isAutoIncrement = 0;

tfield->isPrimaryKey = 0;

tfield->isUnique = 0;

tfield->isNotNull = 0;

// OK-2009-05-26: [[Bug 8065]] - Field data must start out as NULL so we can tell

// whether or not it needs to be freed.

tfield -> data = NULL;

}

return True;

}

/*getRowData - Retrieve the data from the current row.

Output: False on error*/

Bool DBCursor_SQLITE::getRowData()

{

ENTER;

Bool ret = true;

try {

for(int i = 0; i < fieldCount; i++) {

const field_value fv = mDataset->get_field_value_by_index(i);

// OK-2009-05-26: [[Bug 8065]] - Clear out any data from previous records, otherwise we no longer

// have a pointer to it and the memory is lost.

if (fields[i] -> data != NULL)

{

delete fields[i] -> data;

fields[i] -> data = NULL;

}

//distinguish between empty column and null column

fields[i]->isNull = fv.get_isNull();

if(!fields[i]->isNull) {

std::string tmp = fv.get_asString();

// MW-2014-01-29: [[ Sqlite382 ]] If the field type is BLOB and we aren't in binary mode,

// we must decode the data; otherwise we just use the contents directly.

if (fv.get_fType() == ft_Object && !m_enable_binary)

{

// This code has moved from libsqlite/sqlitedataset.cpp:callback().

int bufsize;

bufsize = tmp.size();

char *mybuff;

mybuff = (char *)malloc(bufsize);

memset(mybuff,0,bufsize);

bufsize = sqlite_decode_binary((const unsigned char *)tmp.c_str(), bufsize, ( unsigned char *)mybuff, bufsize);

if (bufsize == -1)

{

fields[i] -> data = NULL;

fields[i] -> dataSize = 0;

fields[i] -> isNull = True;

free(mybuff);

}

else

{

fields[i] -> data = mybuff;

fields[i] -> dataSize = bufsize;

}

else

{

int bufsize = tmp.size();

fields[i]->data = new (nothrow) char[tmp.size() + 1];

memset(fields[i]->data,0,bufsize+1);

memcpy(fields[i]->data, tmp.data(), tmp.size());

fields[i]->dataSize = tmp.size();

}

// OK-2009-05-26: [[Bug 8065]] - Because we copied the data in the line above,

// We have to set FreeBuffer otherwise it will not be freed when the cursor is closed,

// leading to memory leaks.

fields[i] -> freeBuffer = True;

}

MDEBUG("getRowData() -- fv=[%s]\n", fields[i]->data);

}

} catch(DbErrors &e) {

ret = False;

}

return ret;

}