OpenEmuKit/Source/OEXPCGameCoreManager.m

/*
 Copyright (c) 2013, OpenEmu Team

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:
     * Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.
     * Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in the
       documentation and/or other materials provided with the distribution.
     * Neither the name of the OpenEmu Team nor the
       names of its contributors may be used to endorse or promote products
       derived from this software without specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY OpenEmu Team ''AS IS'' AND ANY
 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED. IN NO EVENT SHALL OpenEmu Team BE LIABLE FOR ANY
 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#import "OEXPCGameCoreManager.h"
#import "OEXPCGameCoreHelper.h"
#import "OECorePlugin.h"
#import "OEGameCoreManager_Internal.h"
#import "OESystemPlugin.h"
#import "OEThreadProxy.h"
#import <OpenEmuXPCCommunicator/OpenEmuXPCCommunicator.h>
#import "OEShaderParamValue.h"

@interface OEXPCGameCoreManager ()
{
    NSTask          *_backgroundProcessTask;
    NSString        *_processIdentifier;

    NSXPCConnection *_helperConnection;
    OEThreadProxy   *_gameCoreOwnerProxy;
    BOOL             _isStoppingBackgroundProcess;
}

@property(nonatomic, strong) id<OEXPCGameCoreHelper> gameCoreHelper;
@end

@implementation OEXPCGameCoreManager
@dynamic gameCoreHelper;

- (void)getTerminatingProcesses:(void(^)(NSMutableSet *processes))block
{
    static dispatch_queue_t queue;
    static NSMutableSet *processes;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        queue = dispatch_queue_create("org.openemu.TerminatingXPCProcesses", DISPATCH_QUEUE_SERIAL);
        processes = [NSMutableSet set];
    });

    dispatch_async(queue, ^{
        block(processes);
    });
}

- (void)selfRetain
{
    [self getTerminatingProcesses:
     ^(NSMutableSet *processes)
     {
         [processes addObject:self];
     }];
}

- (void)selfRelease
{
    [self getTerminatingProcesses:
     ^(NSMutableSet *processes)
     {
         [processes removeObject:self];
     }];
}

- (void)loadROMWithCompletionHandler:(void(^)(void))completionHandler errorHandler:(void(^)(NSError *))errorHandler;
{
    _processIdentifier = [NSString stringWithFormat:@"%@ # %@", [[[self ROMPath] lastPathComponent] stringByReplacingOccurrencesOfString:@" " withString:@"-"], [[NSUUID UUID] UUIDString]];
    [self _startHelperProcess];

    [[OEXPCCAgent defaultAgent] retrieveListenerEndpointForIdentifier:_processIdentifier completionHandler:
     ^(NSXPCListenerEndpoint *endpoint)
     {
         if(endpoint == nil)
         {
             NSLog(@"No listener endpoint for identifier: %@", self->_processIdentifier);
             dispatch_async(dispatch_get_main_queue(), ^{
                 NSError *error = [NSError errorWithDomain:OEGameCoreErrorDomain
                                                      code:OEGameCoreCouldNotLoadROMError
                                                  userInfo:nil];
                 errorHandler(error);
                 [self stop];
             });
             
             // There's no listener endpoint, so don't bother trying to create an NSXPCConnection.
             // Returning now since calling initWithListenerEndpoint: and passing it nil results in a memory leak.
             // Also, there's no point in trying to get the gameCoreHelper if there's no _helperConnection.
             return;
         }

         self->_gameCoreOwnerProxy = [OEThreadProxy threadProxyWithTarget:[self gameCoreOwner] thread:[NSThread mainThread]];
         self->_helperConnection = [[NSXPCConnection alloc] initWithListenerEndpoint:endpoint];
        
         [self->_helperConnection setExportedInterface:[NSXPCInterface interfaceWithProtocol:@protocol(OEGameCoreOwner)]];
         [self->_helperConnection setExportedObject:self->_gameCoreOwnerProxy];

         NSXPCInterface *intf = [NSXPCInterface interfaceWithProtocol:@protocol(OEXPCGameCoreHelper)];
         NSSet *set = [NSSet setWithObjects:OEShaderParamValue.class, NSArray.class, OEShaderParamGroupValue.class, nil];
         [intf setClasses:set forSelector:@selector(shaderParamGroupsWithCompletionHandler:) argumentIndex:0 ofReply:YES];
        
         [self->_helperConnection setRemoteObjectInterface:intf];
         [self->_helperConnection resume];

         __block void *gameCoreHelperPointer;
         id<OEXPCGameCoreHelper> gameCoreHelper =
         [self->_helperConnection remoteObjectProxyWithErrorHandler:
          ^(NSError *error)
          {
              NSLog(@"Helper Connection (%p) failed with error: %@", gameCoreHelperPointer, error);
              dispatch_async(dispatch_get_main_queue(), ^{
                  errorHandler(error);
                  [self stop];
              });
          }];

         gameCoreHelperPointer = (__bridge void *)gameCoreHelper;

         if(gameCoreHelper == nil) return;

         [gameCoreHelper loadROMAtPath:[self ROMPath] romCRC32:[self ROMCRC32] romMD5:[self ROMMD5] romHeader:[self ROMHeader] romSerial:[self ROMSerial] systemRegion:[self systemRegion] displayModeInfo:[self displayModeInfo] usingCorePluginAtPath:[[self plugin] path] systemPluginPath:[[self systemPlugin] path] completionHandler:
          ^(NSError *error)
          {
              if(error != nil)
              {
                  dispatch_async(dispatch_get_main_queue(), ^{
                      errorHandler(error);
                      [self stop];
                  });

                  // There's no listener endpoint, so don't bother trying to create an NSXPCConnection.
                  // Returning now since calling initWithListenerEndpoint: and passing it nil results in a memory leak.
                  return;
              }

              [self setGameCoreHelper:gameCoreHelper];
              dispatch_async(dispatch_get_main_queue(), ^{
                  completionHandler();
              });
          }];
     }];
}

- (void)_startHelperProcess
{
    OEXPCCAgentConfiguration *configuration = [OEXPCCAgentConfiguration defaultConfiguration];

    NSString *helperPath = [[NSBundle mainBundle] pathForResource:@"OpenEmuHelperApp" ofType:nil];
    _backgroundProcessTask = [[NSTask alloc] init];

    [_backgroundProcessTask setExecutableURL:[NSURL fileURLWithPath:helperPath]];
    [_backgroundProcessTask setCurrentDirectoryURL:[NSURL fileURLWithPath:[helperPath stringByDeletingLastPathComponent]]];
    [_backgroundProcessTask setArguments:@[ [configuration agentServiceNameProcessArgument], [configuration processIdentifierArgumentForIdentifier:_processIdentifier] ]];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_taskDidTerminate:) name:NSTaskDidTerminateNotification object:_backgroundProcessTask];
    
    BOOL logCoreOutput = [[NSUserDefaults standardUserDefaults] boolForKey:@"OELogCoreOutput"];

    if (logCoreOutput) {
        NSLog(@"Will log core output for %@", _processIdentifier);
        
        __block int fildes[2] = {0};
        pipe(fildes);
        NSFileHandle *writeFh = [[NSFileHandle alloc] initWithFileDescriptor:fildes[1] closeOnDealloc:YES];
        [_backgroundProcessTask setStandardOutput:writeFh];
        [_backgroundProcessTask setStandardError:writeFh];
        
        int readFildes = fildes[0];
        NSString *pidcopy = _processIdentifier;
        dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0), ^{
            FILE *fp = fdopen(readFildes, "r");
            char *linep = NULL;
            size_t linecap = 0;
            ssize_t linelen = getline(&linep, &linecap, fp);
            while (linelen > 0) {
                fputs(linep, stdout);
                linelen = getline(&linep, &linecap, fp);
            }
            free(linep);
            fclose(fp);
            NSLog(@"Helper app %@ has terminated", pidcopy);
        });
    } else {
        /* Do not even receive the core output if we're not doing anything with it
         * to save CPU time */
        [_backgroundProcessTask setStandardOutput:[NSFileHandle fileHandleWithNullDevice]];
        [_backgroundProcessTask setStandardError:[NSFileHandle fileHandleWithNullDevice]];
    }

    [_backgroundProcessTask launch];
}

- (void)stop
{
    if(_isStoppingBackgroundProcess) return;

    _isStoppingBackgroundProcess = YES;

    [self selfRetain];

    [self setGameCoreHelper:nil];
    _gameCoreOwnerProxy = nil;

    [_helperConnection invalidate];
    _helperConnection = nil;

    [_backgroundProcessTask terminate];
}

- (void)_taskDidTerminate:(NSNotification *)notification
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];

    _backgroundProcessTask = nil;

    DLog(@"Did stop background process.");

    [self selfRelease];
}


@end