sameduck/QuickLook/main.c

/* This is an Apple-provided "bootstrap" code for Quick Look generators, nothing intersting here. */

#include <CoreFoundation/CoreFoundation.h>
#include <CoreFoundation/CFPlugInCOM.h>
#include <CoreServices/CoreServices.h>
#include <QuickLook/QuickLook.h>

// -----------------------------------------------------------------------------
//	constants
// -----------------------------------------------------------------------------

// Don't modify this line
#define PLUGIN_ID "48BC750C-2BB9-49B1-AE80-786E22B3DEB4"

//
// Below is the generic glue code for all plug-ins.
//
// You should not have to modify this code aside from changing
// names if you decide to change the names defined in the Info.plist
//


// -----------------------------------------------------------------------------
//	typedefs
// -----------------------------------------------------------------------------

OSStatus GenerateThumbnailForURL(void *thisInterface, QLThumbnailRequestRef thumbnail, CFURLRef url, CFStringRef contentTypeUTI, CFDictionaryRef options, CGSize maxSize);
OSStatus GeneratePreviewForURL(void *thisInterface, QLPreviewRequestRef preview, CFURLRef url, CFStringRef contentTypeUTI, CFDictionaryRef options);

// The layout for an instance of QuickLookGeneratorPlugIn
typedef struct __QuickLookGeneratorPluginType
{
    void        *conduitInterface;
    CFUUIDRef    factoryID;
    UInt32       refCount;
} QuickLookGeneratorPluginType;

// -----------------------------------------------------------------------------
//	prototypes
// -----------------------------------------------------------------------------
//	Forward declaration for the IUnknown implementation.
//

QuickLookGeneratorPluginType  *AllocQuickLookGeneratorPluginType(CFUUIDRef inFactoryID);
void                         DeallocQuickLookGeneratorPluginType(QuickLookGeneratorPluginType *thisInstance);
HRESULT                      QuickLookGeneratorQueryInterface(void *thisInstance,REFIID iid,LPVOID *ppv);
void                        *QuickLookGeneratorPluginFactory(CFAllocatorRef allocator,CFUUIDRef typeID);
ULONG                        QuickLookGeneratorPluginAddRef(void *thisInstance);
ULONG                        QuickLookGeneratorPluginRelease(void *thisInstance);

// -----------------------------------------------------------------------------
//	myInterfaceFtbl	definition
// -----------------------------------------------------------------------------
//	The QLGeneratorInterfaceStruct function table.
//
static QLGeneratorInterfaceStruct myInterfaceFtbl = {
    NULL,
    QuickLookGeneratorQueryInterface,
    QuickLookGeneratorPluginAddRef,
    QuickLookGeneratorPluginRelease,
    NULL,
    NULL,
    NULL,
    NULL
};


// -----------------------------------------------------------------------------
//	AllocQuickLookGeneratorPluginType
// -----------------------------------------------------------------------------
//	Utility function that allocates a new instance.
//      You can do some initial setup for the generator here if you wish
//      like allocating globals etc...
//
QuickLookGeneratorPluginType *AllocQuickLookGeneratorPluginType(CFUUIDRef inFactoryID)
{
    QuickLookGeneratorPluginType *theNewInstance;

    theNewInstance = (QuickLookGeneratorPluginType *)malloc(sizeof(QuickLookGeneratorPluginType));
    memset(theNewInstance,0,sizeof(QuickLookGeneratorPluginType));

        /* Point to the function table Malloc enough to store the stuff and copy the filler from myInterfaceFtbl over */
    theNewInstance->conduitInterface = malloc(sizeof(QLGeneratorInterfaceStruct));
    memcpy(theNewInstance->conduitInterface,&myInterfaceFtbl,sizeof(QLGeneratorInterfaceStruct));

        /*  Retain and keep an open instance refcount for each factory. */
    theNewInstance->factoryID = CFRetain(inFactoryID);
    CFPlugInAddInstanceForFactory(inFactoryID);

        /* This function returns the IUnknown interface so set the refCount to one. */
    theNewInstance->refCount = 1;
    return theNewInstance;
}

// -----------------------------------------------------------------------------
//	DeallocQuickLookGeneratorPluginType
// -----------------------------------------------------------------------------
//	Utility function that deallocates the instance when
//	the refCount goes to zero.
//      In the current implementation generator interfaces are never deallocated
//      but implement this as this might change in the future
//
void DeallocQuickLookGeneratorPluginType(QuickLookGeneratorPluginType *thisInstance)
{
    CFUUIDRef theFactoryID;

    theFactoryID = thisInstance->factoryID;
        /* Free the conduitInterface table up */
    free(thisInstance->conduitInterface);

        /* Free the instance structure */
    free(thisInstance);
    if (theFactoryID){
        CFPlugInRemoveInstanceForFactory(theFactoryID);
        CFRelease(theFactoryID);
    }
}

// -----------------------------------------------------------------------------
//	QuickLookGeneratorQueryInterface
// -----------------------------------------------------------------------------
//	Implementation of the IUnknown QueryInterface function.
//
HRESULT QuickLookGeneratorQueryInterface(void *thisInstance,REFIID iid,LPVOID *ppv)
{
    CFUUIDRef interfaceID;

    interfaceID = CFUUIDCreateFromUUIDBytes(kCFAllocatorDefault,iid);

    if (CFEqual(interfaceID,kQLGeneratorCallbacksInterfaceID)){
            /* If the Right interface was requested, bump the ref count,
             * set the ppv parameter equal to the instance, and
             * return good status.
             */
        ((QLGeneratorInterfaceStruct *)((QuickLookGeneratorPluginType *)thisInstance)->conduitInterface)->GenerateThumbnailForURL = GenerateThumbnailForURL;
        ((QLGeneratorInterfaceStruct *)((QuickLookGeneratorPluginType *)thisInstance)->conduitInterface)->GeneratePreviewForURL = GeneratePreviewForURL;
        ((QLGeneratorInterfaceStruct *)((QuickLookGeneratorPluginType*)thisInstance)->conduitInterface)->AddRef(thisInstance);
        *ppv = thisInstance;
        CFRelease(interfaceID);
        return S_OK;
    }else{
        /* Requested interface unknown, bail with error. */
        *ppv = NULL;
        CFRelease(interfaceID);
        return E_NOINTERFACE;
    }
}

// -----------------------------------------------------------------------------
// QuickLookGeneratorPluginAddRef
// -----------------------------------------------------------------------------
//	Implementation of reference counting for this type. Whenever an interface
//	is requested, bump the refCount for the instance. NOTE: returning the
//	refcount is a convention but is not required so don't rely on it.
//
ULONG QuickLookGeneratorPluginAddRef(void *thisInstance)
{
    ((QuickLookGeneratorPluginType *)thisInstance )->refCount += 1;
    return ((QuickLookGeneratorPluginType*) thisInstance)->refCount;
}

// -----------------------------------------------------------------------------
// QuickLookGeneratorPluginRelease
// -----------------------------------------------------------------------------
//	When an interface is released, decrement the refCount.
//	If the refCount goes to zero, deallocate the instance.
//
ULONG QuickLookGeneratorPluginRelease(void *thisInstance)
{
    ((QuickLookGeneratorPluginType*)thisInstance)->refCount -= 1;
    if (((QuickLookGeneratorPluginType*)thisInstance)->refCount == 0){
        DeallocQuickLookGeneratorPluginType((QuickLookGeneratorPluginType*)thisInstance );
        return 0;
    }else{
        return ((QuickLookGeneratorPluginType*) thisInstance )->refCount;
    }
}

// -----------------------------------------------------------------------------
//  QuickLookGeneratorPluginFactory
// -----------------------------------------------------------------------------
void *QuickLookGeneratorPluginFactory(CFAllocatorRef allocator,CFUUIDRef typeID)
{
    QuickLookGeneratorPluginType *result;
    CFUUIDRef                 uuid;

        /* If correct type is being requested, allocate an
         * instance of kQLGeneratorTypeID and return the IUnknown interface.
         */
    if (CFEqual(typeID,kQLGeneratorTypeID)){
        uuid = CFUUIDCreateFromString(kCFAllocatorDefault,CFSTR(PLUGIN_ID));
        result = AllocQuickLookGeneratorPluginType(uuid);
        CFRelease(uuid);
        return result;
    }
        /* If the requested type is incorrect, return NULL. */
    return NULL;
}