Added online backup functionality.

Tests/FMDatabaseOnlineBackupTests.m

@@ -0,0 +1,94 @@
+//
+//  FMDatabaseOnlineBackupTests.m
+//  fmdb
+//
+//  Created by Mark Pustjens <pustjens@dds.nl> on 23/09/15.
+//  (c) Angelbird Technologies GmbH
+//
+//
+
+#import <Cocoa/Cocoa.h>
+#import <XCTest/XCTest.h>
+
+@interface FMDatabaseOnlineBackupTests : FMDBTempDBTests
+
+@end
+
+@implementation FMDatabaseOnlineBackupTests
+
++ (void)populateDatabase:(FMDatabase *)db
+{
+	[db executeUpdate:@"create table test (a text, b text, c integer, d double, e double)"];
+
+	[db beginTransaction];
+	int i = 0;
+	while (i++ < 2000) {
+		[db executeUpdate:@"insert into test (a, b, c, d, e) values (?, ?, ?, ?, ?)" ,
+		 @"hi'", // look!  I put in a ', and I'm not escaping it!
+		 [NSString stringWithFormat:@"number %d", i],
+		 [NSNumber numberWithInt:i],
+		 [NSDate date],
+		 [NSNumber numberWithFloat:2.2f]];
+	}
+	[db commit];
+}
+
+- (void)setUp {
+    [super setUp];
+    // Put setup code here. This method is called before the invocation of each test method in the class.
+}
+
+- (void)tearDown {
+    // Put teardown code here. This method is called after the invocation of each test method in the class.
+    [super tearDown];
+}
+
+- (void)testBackupDatabase
+{
+	NSString *backupPath = @"/tmp/tmp.db.bck";
+
+	// perform the backup
+	XCTAssertTrue ([self.db backupTo:backupPath withKey:nil andProgressBlock:^(int pagesRemaining, int pageCount) {
+		// No need to show progress.
+	}], @"Should have succeeded");
+
+	// check if the backup file exists
+	NSFileManager *fileManager = [NSFileManager defaultManager];
+	XCTAssertTrue([fileManager fileExistsAtPath:backupPath],
+				  @"Backup db file should exist");
+
+	// test if the bakcup is ok
+	FMDatabase *bck = [FMDatabase databaseWithPath:backupPath];
+	XCTAssertTrue([bck open], @"Should pass");
+	XCTAssert([bck executeQuery:@"select * from test"] != nil, @"Should pass");
+	XCTAssertTrue([bck close], @"Should pass");
+
+	// delete backup
+	[fileManager removeItemAtPath:backupPath error:NULL];
+}
+
+- (void)testBackupDatabaseEncrypted
+{
+	NSString *backupPath = @"/tmp/tmp.edb.bck";
+
+	// perform the backup
+	XCTAssertTrue ([self.db backupTo:backupPath withKey:@"passw0rd" andProgressBlock:^(int pagesRemaining, int pageCount) {
+		// No need to show progress.
+	}], @"Should have succeeded");
+
+	// check if the backup file exists
+	NSFileManager *fileManager = [NSFileManager defaultManager];
+	XCTAssertTrue([fileManager fileExistsAtPath:backupPath],
+				  @"Backup db file should exist");
+
+	// test if the backup is ok
+	FMDatabase *bck = [FMDatabase databaseWithPath:backupPath];
+	XCTAssertTrue([bck open], @"Should pass");
+	XCTAssert([bck executeQuery:@"select * from test"] != nil, @"Should pass");
+	XCTAssertTrue([bck close], @"Should pass");
+
+	// delete backup
+	[fileManager removeItemAtPath:backupPath error:NULL];
+}
+
+@end

fmdb.xcodeproj/project.pbxproj

@@ -15,6 +15,7 @@
 		621721B61892BFE30006691F /* FMDatabasePool.m in Sources */ = {isa = PBXBuildFile; fileRef = CC9E4EB813B31188005F9210 /* FMDatabasePool.m */; };
 		6290CBB7188FE836009790F8 /* Foundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 6290CBB6188FE836009790F8 /* Foundation.framework */; };
 		67CB1E3019AD27D000A3CA7F /* FMDatabaseFTS3Tests.m in Sources */ = {isa = PBXBuildFile; fileRef = 67CB1E2F19AD27D000A3CA7F /* FMDatabaseFTS3Tests.m */; };
+		8081C06C1BB319E200CA7C73 /* FMDatabaseOnlineBackupTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 8081C06B1BB319E200CA7C73 /* FMDatabaseOnlineBackupTests.m */; };
 		8314AF3318CD73D600EC0E25 /* FMDB.h in Headers */ = {isa = PBXBuildFile; fileRef = 8314AF3218CD73D600EC0E25 /* FMDB.h */; };
 		8DD76F9C0486AA7600D96B5E /* Foundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 08FB779EFE84155DC02AAC07 /* Foundation.framework */; };
 		8DD76F9F0486AA7600D96B5E /* fmdb.1 in CopyFiles */ = {isa = PBXBuildFile; fileRef = C6859EA3029092ED04C91782 /* fmdb.1 */; };
@@ -95,6 +96,7 @@
 		6290CBB6188FE836009790F8 /* Foundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Foundation.framework; path = System/Library/Frameworks/Foundation.framework; sourceTree = SDKROOT; };
 		6290CBC6188FE837009790F8 /* UIKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = UIKit.framework; path = Library/Frameworks/UIKit.framework; sourceTree = DEVELOPER_DIR; };
 		67CB1E2F19AD27D000A3CA7F /* FMDatabaseFTS3Tests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FMDatabaseFTS3Tests.m; sourceTree = "<group>"; };
+		8081C06B1BB319E200CA7C73 /* FMDatabaseOnlineBackupTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FMDatabaseOnlineBackupTests.m; sourceTree = "<group>"; };
 		8314AF3218CD73D600EC0E25 /* FMDB.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = FMDB.h; path = src/fmdb/FMDB.h; sourceTree = "<group>"; };
 		831DE6FD175B7C9C001F7317 /* README.markdown */ = {isa = PBXFileReference; lastKnownFileType = text; path = README.markdown; sourceTree = "<group>"; };
 		832F502419EC4C6B0087DCBF /* FMDatabaseVariadic.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; name = FMDatabaseVariadic.swift; path = "src/extra/Swift extensions/FMDatabaseVariadic.swift"; sourceTree = "<group>"; };
@@ -308,6 +310,7 @@
 				BF940F5A18417D490001E077 /* FMDBTempDBTests.h */,
 				BF940F5B18417D490001E077 /* FMDBTempDBTests.m */,
 				3354379B19E71096005661F3 /* FMResultSetTests.m */,
+				8081C06B1BB319E200CA7C73 /* FMDatabaseOnlineBackupTests.m */,
 				BF5D041B18416BB2008C5AA9 /* Supporting Files */,
 			);
 			path = Tests;
@@ -512,6 +515,7 @@
 			files = (
 				BFC152B118417F0D00605DF7 /* FMDatabaseAdditions.m in Sources */,
 				CCA66A3019C0CB1900EFDAC1 /* FMTokenizers.m in Sources */,
+				8081C06C1BB319E200CA7C73 /* FMDatabaseOnlineBackupTests.m in Sources */,
 				BF940F5C18417D490001E077 /* FMDBTempDBTests.m in Sources */,
 				BF940F5E18417DEA0001E077 /* FMDatabaseAdditionsTests.m in Sources */,
 				3354379C19E71096005661F3 /* FMResultSetTests.m in Sources */,

src/fmdb/FMDatabase.h

@@ -859,6 +859,26 @@ typedef int(^FMDBExecuteStatementsCallbackBlock)(NSDictionary *resultsDictionary
 
 #endif
 
+///----------------------------
+/// @name Online Backup
+///----------------------------
+
+/** Perform a live backup of the database to a new file
+
+ @param path Path of the file to write the backup to
+ @param key The encryption key to use for the target database.
+ @param block Block to call with progress updates
+
+ @return@return `YES` if successful, `NO` on error.
+
+ @see [Using the SQLite Online Backup API()](http://sqlite.org/backup.html)
+
+ */
+
+- (BOOL)backupTo:(NSString*)aPath
+		 withKey:(NSString*)key
+andProgressBlock:(void (^)(int pagesRemaining, int pageCount))progressBlock;
+
 ///----------------------------
 /// @name SQLite library status
 ///----------------------------

src/fmdb/FMDatabase.m

@@ -1330,6 +1330,82 @@ - (NSError*)inSavePoint:(void (^)(BOOL *rollback))block {
 
 #endif
 
+#pragma mark Online backup
+
+- (BOOL)backupTo:(NSString*)aPath
+		 withKey:(NSString*)key
+andProgressBlock:(void (^)(int pagesRemaining, int pageCount))progressBlock
+{
+	NSParameterAssert(aPath);
+	NSParameterAssert(progressBlock);
+
+	if (![self databaseExists]) {
+		return NO;
+	}
+
+	if (_isExecutingStatement) {
+		[self warnInUse];
+		return NO;
+	}
+
+	_isExecutingStatement = YES;
+
+	int err					= 0;
+	sqlite3 *pFile			= NULL;
+	sqlite3_backup *pBackup	= NULL;
+
+	if (_traceExecution) {
+		NSLog(@"%@ backupTo: %@", self, aPath);
+	}
+
+	err = sqlite3_open([aPath fileSystemRepresentation], &pFile);
+	if (err != SQLITE_OK) {
+		goto backupTowithProgressBlockDone;
+	}
+#ifdef SQLITE_HAS_CODEC
+	if (key) {
+		NSData *keyData = [NSData dataWithBytes:[key UTF8String] length:(NSUInteger)strlen([key UTF8String])];
+		err = sqlite3_key(pFile, [keyData bytes], (int)[keyData length]);
+		if (err != SQLITE_OK) {
+			goto backupTowithProgressBlockDone;
+		}
+	}
+#endif
+
+	/* Open the backup object to accomplish the backup. */
+	pBackup = sqlite3_backup_init(pFile, "main", _db, "main");
+	if (!pBackup) {
+		goto backupTowithProgressBlockDone;
+	}
+
+	do {
+		err = sqlite3_backup_step(pBackup, 10); //TODO optimize page count
+		progressBlock(sqlite3_backup_remaining(pBackup), sqlite3_backup_pagecount(pBackup));
+
+		//if (err == SQLITE_OK || err == SQLITE_BUSY || err == SQLITE_LOCKED) {
+		//	sqlite3_sleep(5);
+		//}
+	} while (err == SQLITE_OK || err == SQLITE_BUSY || err == SQLITE_LOCKED);
+
+	/* Release resources allocated by backup_init(). */
+	sqlite3_backup_finish(pBackup);
+
+
+backupTowithProgressBlockDone:
+
+	err = sqlite3_errcode(pFile);
+	if (err != SQLITE_OK) {
+		NSString *msg = [NSString stringWithUTF8String:sqlite3_errmsg(pFile)];
+		NSLog(@"error performing backup: %d \"%@\"", err, msg);
+	}
+
+	_isExecutingStatement = NO;
+
+	sqlite3_close (pFile);
+
+	return (err == SQLITE_OK);
+}
+
 #pragma mark Cache statements
 
 - (BOOL)shouldCacheStatements {