SUPlainInstaller.m

//
//  SUPlainInstaller.m
//  Sparkle
//
//  Created by Andy Matuschak on 4/10/08.
//  Copyright 2008 Andy Matuschak. All rights reserved.
//

#import "SUPlainInstaller.h"
#import "SUPlainInstallerInternals.h"
#import "SUConstants.h"
#import "SUHost.h"

static NSString * const SUInstallerPathKey = @"SUInstallerPath";
static NSString * const SUInstallerTargetPathKey = @"SUInstallerTargetPath";
static NSString * const SUInstallerTempNameKey = @"SUInstallerTempName";
static NSString * const SUInstallerHostKey = @"SUInstallerHost";
static NSString * const SUInstallerDelegateKey = @"SUInstallerDelegate";
static NSString * const SUInstallerResultKey = @"SUInstallerResult";
static NSString * const SUInstallerErrorKey = @"SUInstallerError";
static NSString * const SUInstallerInstallationPathKey = @"SUInstallerInstallationPath";

@implementation SUPlainInstaller

+ (void)finishInstallationWithInfo:(NSDictionary *)info
{
	// *** GETS CALLED ON NON-MAIN THREAD!

	[self finishInstallationToPath:info[SUInstallerInstallationPathKey] withResult:[info[SUInstallerResultKey] boolValue] host:info[SUInstallerHostKey] error:info[SUInstallerErrorKey] delegate:info[SUInstallerDelegateKey]];
}

+ (void)performInstallationWithInfo:(NSDictionary *)info
{
	// *** GETS CALLED ON NON-MAIN THREAD!

	@autoreleasepool {
		NSError *error = nil;

		NSString	*	oldPath = [info[SUInstallerHostKey] bundlePath];
		NSString	*	installationPath = info[SUInstallerInstallationPathKey];
		BOOL result = [self copyPathWithAuthentication:info[SUInstallerPathKey] overPath: installationPath temporaryName:info[SUInstallerTempNameKey] error:&error];

		if( result )
		{
			BOOL	haveOld = [[NSFileManager defaultManager] fileExistsAtPath: oldPath];
			BOOL	differentFromNew = ![oldPath isEqualToString: installationPath];
			if( haveOld && differentFromNew )
				[self _movePathToTrash: oldPath];	// On success, trash old copy if there's still one due to renaming.
		}
		NSMutableDictionary *mutableInfo = [[info mutableCopy] autorelease];
		mutableInfo[SUInstallerResultKey] = @(result);
		mutableInfo[SUInstallerInstallationPathKey] = installationPath;
		if (!result && error)
			mutableInfo[SUInstallerErrorKey] = error;
		dispatch_async(dispatch_get_main_queue(), ^{
			[self finishInstallationWithInfo:mutableInfo];
		});
	}
}

+ (void)performInstallationToPath:(NSString *)installationPath fromPath:(NSString *)path host:(SUHost *)host delegate:(id<SUInstallerDelegate>)delegate synchronously:(BOOL)synchronously versionComparator:(id <SUVersionComparison>)comparator
{
	// Prevent malicious downgrades:
	#if !PERMIT_AUTOMATED_DOWNGRADES
	if ([comparator compareVersion:[host version] toVersion:[[NSBundle bundleWithPath:path] objectForInfoDictionaryKey:@"CFBundleVersion"]] == NSOrderedDescending)
	{
		NSString * errorMessage = [NSString stringWithFormat:@"Sparkle Updater: Possible attack in progress! Attempting to \"upgrade\" from %@ to %@. Aborting update.", [host version], [[NSBundle bundleWithPath:path] objectForInfoDictionaryKey:@"CFBundleVersion"]];
		NSError *error = [NSError errorWithDomain:SUSparkleErrorDomain code:SUDowngradeError userInfo:@{NSLocalizedDescriptionKey: errorMessage}];
		[self finishInstallationToPath:installationPath withResult:NO host:host error:error delegate:delegate];
		return;
	}
	#endif

    NSString *targetPath = [host installationPath];
    NSString *tempName = [self temporaryNameForPath:targetPath];
	NSDictionary *info = @{SUInstallerPathKey: path, SUInstallerTargetPathKey: targetPath, SUInstallerTempNameKey: tempName, SUInstallerHostKey: host, SUInstallerDelegateKey: delegate, SUInstallerInstallationPathKey: installationPath};
	if (synchronously)
		[self performInstallationWithInfo:info];
	else {
		dispatch_async(dispatch_get_global_queue(0, 0), ^{
			[self performInstallationWithInfo:info];
		});
	}
}

@end