TIP529 image metadata: changed driver interface: split metadata to in/out object, driver communication dstring, file close flag, reorder all options in a more logical order. Forking intended, will merge later. Thanks Jan, for your work.

4 files changed, 230 insertions, 248 deletions

diff --git a/generic/tk.h b/generic/tk.h
index 5aa8998..cd16ce0 100644
--- a/generic/tk.h
+++ b/generic/tk.h
@@ -1441,26 +1441,29 @@ typedef int (Tk_ImageStringWriteProc) (Tcl_Interp *interp, Tcl_Obj *format,
 
 /*
  * The following alternate definitions are used with the Tk8.7 file format
- * supporting a metadata dict
+ * supporting a metadata dict, internal dstring and close file flag
  */
 
 typedef struct Tk_PhotoImageFormat87 Tk_PhotoImageFormat87;
-typedef int (Tk_ImageFileMatchProc87) (Tcl_Channel chan, const char *fileName,
-	Tcl_Obj *format, int *widthPtr, int *heightPtr, Tcl_Interp *interp,
-	Tcl_Obj **metadataPtr);
-typedef int (Tk_ImageStringMatchProc87) (Tcl_Obj *dataObj, Tcl_Obj *format,
-	int *widthPtr, int *heightPtr, Tcl_Interp *interp, Tcl_Obj **metadataPtr);
+typedef int (Tk_ImageFileMatchProc87) (Tcl_Interp *interp, Tcl_Channel chan,
+	const char *fileName, Tcl_Obj *format, Tcl_Obj *metadataIn, int *widthPtr,
+	int *heightPtr, int *closeChannelPtr, Tcl_DString *driverInternal);
+typedef int (Tk_ImageStringMatchProc87) (Tcl_Interp *interp, Tcl_Obj *dataObj,
+	Tcl_Obj *format, Tcl_Obj *metadataIn, int *widthPtr, int *heightPtr,
+	Tcl_DString *driverInternal);
 typedef int (Tk_ImageFileReadProc87) (Tcl_Interp *interp, Tcl_Channel chan,
-	const char *fileName, Tcl_Obj *format, Tk_PhotoHandle imageHandle,
+	const char *fileName, Tcl_Obj *format, Tcl_Obj *metadataIn,
+	Tk_PhotoHandle imageHandle,
 	int destX, int destY, int width, int height, int srcX, int srcY,
-	Tcl_Obj **metadataPtr);
+	Tcl_Obj *metadataOut, Tcl_DString *driverInternal);
 typedef int (Tk_ImageStringReadProc87) (Tcl_Interp *interp, Tcl_Obj *dataObj,
-	Tcl_Obj *format, Tk_PhotoHandle imageHandle, int destX, int destY,
-	int width, int height, int srcX, int srcY, Tcl_Obj **metadataPtr);
+	Tcl_Obj *format, Tcl_Obj *metadataIn, Tk_PhotoHandle imageHandle,
+	int destX, int destY, int width, int height, int srcX, int srcY,
+	Tcl_Obj *metadataOut, Tcl_DString *driverInternal);
 typedef int (Tk_ImageFileWriteProc87) (Tcl_Interp *interp, const char *fileName,
-	Tcl_Obj *format, Tk_PhotoImageBlock *blockPtr, Tcl_Obj *metadata);
+	Tcl_Obj *format, Tcl_Obj *metadataIn, Tk_PhotoImageBlock *blockPtr);
 typedef int (Tk_ImageStringWriteProc87) (Tcl_Interp *interp, Tcl_Obj *format,
-	Tk_PhotoImageBlock *blockPtr, Tcl_Obj *metadata);
+	Tcl_Obj *metadataIn, Tk_PhotoImageBlock *blockPtr);
 
 
 /*
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c
index 1036bae..f9f0bea 100644
--- a/generic/tkImgGIF.c
+++ b/generic/tkImgGIF.c
@@ -118,29 +118,33 @@ typedef size_t (WriteBytesFunc) (ClientData clientData, const char *bytes,
  * The format record for the GIF file format:
  */
 
-static int		FileMatchGIF(Tcl_Channel chan, const char *fileName,
-			    Tcl_Obj *format, int *widthPtr, int *heightPtr,
-			    Tcl_Interp *interp, Tcl_Obj **metadataPtr);
+static int		FileMatchGIF(Tcl_Interp *interp, Tcl_Channel chan,
+			    const char *fileName, Tcl_Obj *format,
+			    Tcl_Obj *metadataIn, int *widthPtr, int *heightPtr,
+			    int *closeChannelPtr, Tcl_DString *driverInternal);
 static int		FileReadGIF(Tcl_Interp *interp, Tcl_Channel chan,
 			    const char *fileName, Tcl_Obj *format,
-			    Tk_PhotoHandle imageHandle, int destX, int destY,
-			    int width, int height, int srcX, int srcY,
-			    Tcl_Obj **metadataPtr);
-static int		StringMatchGIF(Tcl_Obj *dataObj, Tcl_Obj *format,
-			    int *widthPtr, int *heightPtr, Tcl_Interp *interp,
-			    Tcl_Obj **metadataPtr);
+			    Tcl_Obj *metadataIn, Tk_PhotoHandle imageHandle,
+			    int destX, int destY, int width, int height,
+			    int srcX, int srcY,
+			    Tcl_Obj *metadataOut, Tcl_DString *driverInternal);
+static int		StringMatchGIF(Tcl_Interp *interp, Tcl_Obj *dataObj,
+			    Tcl_Obj *format, Tcl_Obj *metadataIn, int *widthPtr,
+			    int *heightPtr, Tcl_DString *driverInternal);
 static int		StringReadGIF(Tcl_Interp *interp, Tcl_Obj *dataObj,
-			    Tcl_Obj *format, Tk_PhotoHandle imageHandle,
+			    Tcl_Obj *format, Tcl_Obj *metadataIn,
+			    Tk_PhotoHandle imageHandle,
 			    int destX, int destY, int width, int height,
-			    int srcX, int srcY, Tcl_Obj **metadataPtr);
+			    int srcX, int srcY,
+			    Tcl_Obj *metadataOut, Tcl_DString *driverInternal);
 static int		FileWriteGIF(Tcl_Interp *interp, const char *filename,
-			    Tcl_Obj *format, Tk_PhotoImageBlock *blockPtr,
-			    Tcl_Obj *metadata);
+			    Tcl_Obj *format, Tcl_Obj *metadataIn,
+			    Tk_PhotoImageBlock *blockPtr);
 static int		StringWriteGIF(Tcl_Interp *interp, Tcl_Obj *format,
-			    Tk_PhotoImageBlock *blockPtr, Tcl_Obj *metadata);
+			     Tcl_Obj *metadataIn, Tk_PhotoImageBlock *blockPtr);
 static int		CommonWriteGIF(Tcl_Interp *interp, ClientData clientData,
 			    WriteBytesFunc *writeProc, Tcl_Obj *format,
-			    Tk_PhotoImageBlock *blockPtr, Tcl_Obj *metadata);
+			    Tcl_Obj *metadataIn, Tk_PhotoImageBlock *blockPtr);
 
 Tk_PhotoImageFormat87 tkImgFmtGIF = {
     "gif",		/* name */
@@ -172,7 +176,7 @@ static int		ReadOneByte(Tcl_Interp *interp,
 			    GIFImageConfig *gifConfPtr, Tcl_Channel chan);
 static int		DoExtension(GIFImageConfig *gifConfPtr,
 			    Tcl_Channel chan, int label, unsigned char *buffer,
-			    int *transparent, Tcl_Obj *metadata);
+			    int *transparent, Tcl_Obj *metadataOut);
 static int		GetCode(Tcl_Channel chan, int code_size, int flag,
 			    GIFImageConfig *gifConfPtr);
 static int		GetDataBlock(GIFImageConfig *gifConfPtr,
@@ -350,14 +354,16 @@ static void		FlushChar(GIFState_t *statePtr);
 
 static int
 FileMatchGIF(
+    Tcl_Interp *dummy,		/* not used */
     Tcl_Channel chan,		/* The image file, open for reading. */
     const char *fileName,	/* The name of the image file. */
     Tcl_Obj *format,		/* User-specified format object, or NULL. */
+    Tcl_Obj *metadataIn,	/* metadata input, may be NULL */
     int *widthPtr, int *heightPtr,
 				/* The dimensions of the image are returned
 				 * here if the file is a valid raw GIF file. */
-    Tcl_Interp *dummy,		/* not used */
-    Tcl_Obj **metadataPtr)	/* metadata to investigate and to return */
+    int *closeChannelPtr,	/* Return if the channel may be closed */
+    Tcl_DString *driverInternal)/* memory passed to FileReadGIF */
 {
     GIFImageConfig gifConf;
     (void)fileName;
@@ -393,6 +399,7 @@ FileReadGIF(
     Tcl_Channel chan,		/* The image file, open for reading. */
     const char *fileName,	/* The name of the image file. */
     Tcl_Obj *format,		/* User-specified format object, or NULL. */
+    Tcl_Obj *metadataIn,	/* metadata input, may be NULL */
     Tk_PhotoHandle imageHandle,	/* The photo image to write into. */
     int destX, int destY,	/* Coordinates of top-left pixel in photo
 				 * image to be written to. */
@@ -400,8 +407,8 @@ FileReadGIF(
 				 * written to. */
     int srcX, int srcY,		/* Coordinates of top-left pixel to be used in
 				 * image being read. */
-    Tcl_Obj **metadataPtr)	/* metadata to investigate and to return */
-				/* may point to a NULL pointer */
+    Tcl_Obj *metadataOut,	/* metadata return dict, may be NULL */
+    Tcl_DString *driverInternal)/* memory passed from FileMatchGIF */
 {
     int fileWidth, fileHeight, imageWidth, imageHeight;
     unsigned int nBytes;
@@ -410,7 +417,6 @@ FileReadGIF(
     unsigned char buf[100];
     unsigned char *trashBuffer = NULL;
     int bitPixel;
-    Tcl_Obj *metadata;
     int dictSize = 0;
     int gifLabel;
     unsigned char colorMap[MAXCOLORMAPSIZE][4];
@@ -521,28 +527,6 @@ FileReadGIF(
      */
 
     /*
-     * Initialize the metadata dict as an unshared copy of the input metadata.
-     * We do not want to modify the metadataPtr in case of an error.
-     * So first get a local unshared copy, which is assigned on success.
-     */
-
-    metadata = *metadataPtr;
-    if (metadata == NULL) {
-	metadata = Tcl_NewDictObj();
-    } else {
-	if (Tcl_IsShared(metadata)) {
-	    metadata = Tcl_DuplicateObj(metadata);
-	}
-    }
-
-    /*
-     * Start with a ref count of 1 to delete it in the error case with
-     * Tcl_DecrRefCount().
-     */
-
-    Tcl_IncrRefCount(metadata);
-
-    /*
      * Search for the frame from the GIF to display.
      */
 
@@ -567,7 +551,8 @@ FileReadGIF(
 		goto error;
 	    }
 	    if (DoExtension(gifConfPtr, chan, gifLabel,
-		    gifConfPtr->workingBuffer, &transparent, metadata) < 0) {
+		    gifConfPtr->workingBuffer, &transparent, metadataOut)
+		    < 0) {
 		Tcl_SetObjResult(interp, Tcl_NewStringObj(
 			"error reading extension in GIF image", -1));
 		Tcl_SetErrorCode(interp, "TK", "IMAGE", "GIF", "BAD_EXT",
@@ -762,7 +747,8 @@ FileReadGIF(
 		goto error;
 	    }
 	    if (DoExtension(gifConfPtr, chan, gifLabel,
-		    gifConfPtr->workingBuffer, &transparent, metadata) < 0) {
+		    gifConfPtr->workingBuffer, &transparent, metadataOut)
+		    < 0) {
 		Tcl_SetObjResult(interp, Tcl_NewStringObj(
 			"error reading extension in GIF image", -1));
 		Tcl_SetErrorCode(interp, "TK", "IMAGE", "GIF", "BAD_EXT",
@@ -788,30 +774,8 @@ FileReadGIF(
     Tcl_SetObjResult(interp, Tcl_NewStringObj(tkImgFmtGIF.name, -1));
     result = TCL_OK;
 
-    /*
-     * Merge the metadata object if there is data in the dict.
-     */
-
-    if (TCL_OK != (result = Tcl_DictObjSize(interp,metadata, &dictSize))) {
-	goto error;
-    }
-    if (dictSize > 0) {
-	if (*metadataPtr != NULL) {
-	    Tcl_DecrRefCount(*metadataPtr);
-	}
-	*metadataPtr = metadata;
-    }
-
-    /*
-     * If a trash buffer has been allocated, free it now.
-     */
-
-    if (trashBuffer != NULL) {
-	ckfree(trashBuffer);
-    }
-    return result;
-
-  error:
+error:
+    
     /*
      * If a trash buffer has been allocated, free it now.
      */
@@ -819,12 +783,6 @@ FileReadGIF(
     if (trashBuffer != NULL) {
 	ckfree(trashBuffer);
     }
-
-    /*
-     * free the metadata object in case of error.
-     * Otherwise, it is not freed as the ref count was incremented above.
-     */
-    Tcl_DecrRefCount(metadata);
     return result;
 }
 
@@ -888,12 +846,13 @@ ReadOneByte(
 
 static int
 StringMatchGIF(
+    Tcl_Interp *dummy,		/* not used */
     Tcl_Obj *dataObj,		/* the object containing the image data */
     Tcl_Obj *format,		/* the image format object, or NULL */
+    Tcl_Obj *metadataIn,	/* metadata input, may be NULL */
     int *widthPtr,		/* where to put the string width */
     int *heightPtr,		/* where to put the string height */
-    Tcl_Interp *dummy,		/* not used */
-    Tcl_Obj **metadataPtr)	/* metadata to investigate and to return */
+    Tcl_DString *driverInternal)/* memory to pass to StringReadGIF */
 {
     unsigned char *data, header[10];
     TkSizeT got, length;
@@ -961,11 +920,13 @@ StringReadGIF(
     Tcl_Interp *interp,		/* interpreter for reporting errors in */
     Tcl_Obj *dataObj,		/* object containing the image */
     Tcl_Obj *format,		/* format object, or NULL */
+    Tcl_Obj *metadataIn,	/* metadata input, may be NULL */
     Tk_PhotoHandle imageHandle,	/* the image to write this data into */
     int destX, int destY,	/* The rectangular region of the */
     int width, int height,	/* image to copy */
     int srcX, int srcY,
-    Tcl_Obj **metadataPtr)	/* metadata to investigate and to return */
+    Tcl_Obj *metadataOut,	/* metadata return dict, may be NULL */
+    Tcl_DString *driverInternal)/* memory passed from StringReadGIF */
 {
     MFile handle, *hdlPtr = &handle;
     TkSizeT length;
@@ -994,7 +955,9 @@ StringReadGIF(
      */
 
     return FileReadGIF(interp, (Tcl_Channel) hdlPtr, xferFormat, format,
-	    imageHandle, destX, destY, width, height, srcX, srcY, metadataPtr);
+	    metadataIn,
+	    imageHandle, destX, destY, width, height, srcX, srcY,
+	    metadataOut, driverInternal);
 }
 
 /*
@@ -1103,7 +1066,7 @@ DoExtension(
     int label,
     unsigned char *buf, /* defined as 280 byte working buffer */
     int *transparent,
-    Tcl_Obj *metadata)
+    Tcl_Obj *metadataOut)
 {
     int count;
     /* Prepare extension name
@@ -1139,7 +1102,8 @@ DoExtension(
 	    return -1;
 	}
 	/* Detect XMP extension */
-	if (0 == memcmp(buf,"XMP DataXMP",11)) {
+	if (NULL != metadataOut
+		&& 0 == memcmp(buf,"XMP DataXMP",11)) {
 	    /* XMP format does not use the block structure of GIF
 	     * The data is utf-8 which never contains 0's
 	     * A magic trailer of 258 bytes is added with the following data:
@@ -1180,7 +1144,7 @@ DoExtension(
 	    encoding = Tcl_GetEncoding(NULL, "utf-8");
 	    Tcl_DStringInit(&recodedDString);
 	    Tcl_ExternalToUtfDString(encoding, Tcl_DStringValue(&dataDString), length, &recodedDString);
-	    result = Tcl_DictObjPut(NULL, metadata,
+	    result = Tcl_DictObjPut(NULL, metadataOut,
 		    Tcl_NewStringObj("XMP",-1),
 		    Tcl_NewStringObj(Tcl_DStringValue(&recodedDString),
 			Tcl_DStringLength(&recodedDString)));
@@ -1208,7 +1172,8 @@ DoExtension(
 	break;
     }
     /* Add extension to dict */
-    if (extensionStreamName[0] != '\0' ) {
+    if (NULL != metadataOut
+	    && extensionStreamName[0] != '\0' ) {
 	Tcl_Obj *metadataData;
 	int length = 0;
 	for (;;) {
@@ -1218,8 +1183,9 @@ DoExtension(
 		return -1;
 	    case 0: /* end of data */
 		if (length > 0) {
-		    if ( TCL_OK != Tcl_DictObjPut(NULL, metadata,
-			    Tcl_NewByteArrayObj((unsigned char *)extensionStreamName,
+		    if ( TCL_OK != Tcl_DictObjPut(NULL, metadataOut,
+			    Tcl_NewByteArrayObj(
+				(unsigned char *)extensionStreamName,
 			    strlen(extensionStreamName)), metadataData)) {
 			return -1;
 		    }
@@ -1906,8 +1872,8 @@ FileWriteGIF(
     Tcl_Interp *interp,		/* Interpreter to use for reporting errors. */
     const char *filename,
     Tcl_Obj *format,
-    Tk_PhotoImageBlock *blockPtr,
-    Tcl_Obj *metadata)
+    Tcl_Obj *metadata,
+    Tk_PhotoImageBlock *blockPtr)
 {
     Tcl_Channel chan = NULL;
     int result;
@@ -1922,7 +1888,8 @@ FileWriteGIF(
 	return TCL_ERROR;
     }
 
-    result = CommonWriteGIF(interp, chan, WriteToChannel, format, blockPtr, metadata);
+    result = CommonWriteGIF(interp, chan, WriteToChannel, format, metadata,
+	    blockPtr);
 
     if (Tcl_Close(interp, chan) == TCL_ERROR) {
 	return TCL_ERROR;
@@ -1937,15 +1904,15 @@ StringWriteGIF(
     Tcl_Interp *interp,		/* Interpreter to use for reporting errors and
 				 * returning the GIF data. */
     Tcl_Obj *format,
-    Tk_PhotoImageBlock *blockPtr,
-    Tcl_Obj *metadata)
+    Tcl_Obj *metadata,
+    Tk_PhotoImageBlock *blockPtr)
 {
     int result;
     Tcl_Obj *objPtr = Tcl_NewObj();
 
     Tcl_IncrRefCount(objPtr);
     result = CommonWriteGIF(interp, objPtr, WriteToByteArray, format,
-	    blockPtr, metadata);
+	    metadata, blockPtr);
     if (result == TCL_OK) {
 	Tcl_SetObjResult(interp, objPtr);
     }
@@ -1985,8 +1952,8 @@ CommonWriteGIF(
     ClientData handle,
     WriteBytesFunc *writeProc,
     Tcl_Obj *format,
-    Tk_PhotoImageBlock *blockPtr,
-    Tcl_Obj *metadata)
+    Tcl_Obj *metadata,
+    Tk_PhotoImageBlock *blockPtr)
 {
     GifWriterState state;
     int resolution;
diff --git a/generic/tkImgPhoto.c b/generic/tkImgPhoto.c
index ef5f38d..c79f128 100644
--- a/generic/tkImgPhoto.c
+++ b/generic/tkImgPhoto.c
@@ -200,16 +200,21 @@ static char *		ImgGetPhoto(PhotoMaster *masterPtr,
 			    struct SubcommandOptions *optPtr);
 static int		MatchFileFormat(Tcl_Interp *interp, Tcl_Channel chan,
 			    const char *fileName, Tcl_Obj *formatString,
-			    Tcl_Obj **metadataObjPtr,
+			    Tcl_Obj *metadataInObj,
+			    Tcl_Obj *metadataOutObj,
 			    Tk_PhotoImageFormat **imageFormatPtr,
 			    Tk_PhotoImageFormat87 **imageFormat87Ptr,
-			    int *widthPtr, int *heightPtr, int *oldformat);
+			    int *widthPtr, int *heightPtr, int *oldformat,
+			    int *closeChannelPtr,
+			    Tcl_DString *driverInternalPtr);
 static int		MatchStringFormat(Tcl_Interp *interp, Tcl_Obj *data,
 			    Tcl_Obj *formatString,
-			    Tcl_Obj **metadataObjPtr,
+			    Tcl_Obj *metadataInObj,
+			    Tcl_Obj *metadataOutObj,
 			    Tk_PhotoImageFormat **imageFormatPtr,
 			    Tk_PhotoImageFormat87 **imageFormat87Ptr,
-			    int *widthPtr, int *heightPtr, int *oldformat);
+			    int *widthPtr, int *heightPtr, int *oldformat,
+			    Tcl_DString *driverInternalPtr);
 static const char *	GetExtension(const char *path);
 
 /*
@@ -851,7 +856,7 @@ ImgPhotoCmd(
 
 	if (stringWriteProc == NULL) {
 	    result = (stringWriteProc87)(interp,
-		    options.format, &block, options.metadata);
+		    options.format, options.metadata, &block);
 	} else if (oldformat) {
 	    Tcl_DString buffer;
 	    typedef int (*OldStringWriteProc)(Tcl_Interp *interp,
@@ -949,9 +954,9 @@ ImgPhotoCmd(
     }
 
     case PHOTO_PUT: {
-	Tcl_Obj *format, *data, *metadata;
 	int result;
-
+	Tcl_Obj *format, *data;
+	Tcl_DString driverInternalDString;
 	/*
 	 * photo put command - first parse the options.
 	 */
@@ -970,30 +975,24 @@ ImgPhotoCmd(
 	    Tcl_WrongNumArgs(interp, 2, objv, "data ?-option value ...?");
 	    return TCL_ERROR;
 	}
-
+	
 	/*
-	 * Prepare a metadata dict.
-	 * If the object pointer points to NULL, there is no metadata dict on input.
-	 * The match and read calls may modify it and change it from NULL.
-	 * The refcount of options.metadata is >= 1
+	 * Prepare memory connection between format match and read function
 	 */
-	if (options.metadata == NULL) {
-	    metadata = NULL;
-	} else {
-	    metadata = options.metadata;
-	    Tcl_IncrRefCount(metadata);
-	}
+	
+	Tcl_DStringInit(&driverInternalDString);
 
 	/*
 	 * See if there's a format that can read the data
 	 */
 
 	if (MatchStringFormat(interp, objv[2], options.format,
-		&metadata, &imageFormat,
-		&imageFormat87, &imageWidth, &imageHeight, &oldformat)
+		options.metadata, NULL, &imageFormat,
+		&imageFormat87, &imageWidth, &imageHeight, &oldformat,
+		&driverInternalDString)
 		!= TCL_OK) {
 	    result = TCL_ERROR;
-	    goto putsCleanup;
+	    goto putCleanup;
 	}
 
 	if (!(options.options & OPT_TO) || (options.toX2 < 0)) {
@@ -1021,18 +1020,21 @@ ImgPhotoCmd(
 		    options.toX2 - options.toX,
 		    options.toY2 - options.toY, 0, 0) != TCL_OK) {
 		result = TCL_ERROR;
-		goto putsCleanup;
+		goto putCleanup;
 	    }
 	} else {
 	    if (imageFormat87->stringReadProc(interp, data, format,
+		    options.metadata,
 		    (Tk_PhotoHandle) masterPtr, options.toX, options.toY,
 		    options.toX2 - options.toX,
 		    options.toY2 - options.toY, 0, 0,
-		    &metadata) != TCL_OK) {
-                result = TCL_ERROR;
-                goto putsCleanup;
+		    NULL, &driverInternalDString)
+		    != TCL_OK) {
+		result = TCL_ERROR;
+		goto putCleanup;
 	    }
 	}
+
 	/*
 	 * SB: is the next line really needed? The stringReadProc
 	 * writes image data with Tk_PhotoPutBlock(), which in turn
@@ -1040,15 +1042,18 @@ ImgPhotoCmd(
 	 * IMAGE_CHANGED bit.
 	 */
 	masterPtr->flags |= IMAGE_CHANGED;
+
 	result = TCL_OK;
-putsCleanup:
-	if (metadata != NULL)
-	    Tcl_DecrRefCount(metadata);
+putCleanup:
+	Tcl_DStringFree(&driverInternalDString);
 	return result;
+
     }
     case PHOTO_READ: {
-	Tcl_Obj *format, *metadata;
+	Tcl_Obj *format;
 	int result;
+	int closeChannel = 0;
+	Tcl_DString driverInternalDString;
 
 	/*
 	 * photo read command - first parse the options specified.
@@ -1101,22 +1106,16 @@ putsCleanup:
 	}
 
 	/*
-	* Prepare a metadata dict.
-	* If the object pointer points to NULL, there is no metadata dict on input.
-	* The match and read calls may modify it and change it from NULL.
-	* ToDo: think about ref counting and freeing it below
-	*/
-	if (options.metadata == NULL) {
-	    metadata = NULL;
-	} else {
-	    metadata = options.metadata;
-	    Tcl_IncrRefCount(metadata);
-	}
-
+	 * Prepare memory connection between format match and read function
+	 */
+	
+	Tcl_DStringInit(&driverInternalDString);
+	closeChannel = 0;
 	if (MatchFileFormat(interp, chan,
 		Tcl_GetString(options.name), options.format,
-		&metadata, &imageFormat,
-		&imageFormat87, &imageWidth, &imageHeight, &oldformat)
+		options.metadata, NULL, &imageFormat,
+		&imageFormat87, &imageWidth, &imageHeight, &oldformat,
+		&closeChannel, &driverInternalDString)
 		!= TCL_OK) {
 	    result = TCL_ERROR;
 	    goto readCleanup;
@@ -1177,13 +1176,12 @@ putsCleanup:
 	} else {
 	    result = imageFormat87->fileReadProc(interp, chan,
 		    Tcl_GetString(options.name),
-		    format, (Tk_PhotoHandle) masterPtr, options.toX,
-		    options.toY, width, height, options.fromX, options.fromY,
-		    &metadata);
+		    format, options.metadata, (Tk_PhotoHandle) masterPtr,
+		    options.toX, options.toY, width, height, options.fromX,
+		    options.fromY, NULL, &driverInternalDString);
 	}
 readCleanup:
-	if (metadata != NULL)
-	    Tcl_DecrRefCount(metadata);
+	Tcl_DStringFree(&driverInternalDString);
 	if (chan != NULL) {
 	    Tcl_Close(NULL, chan);
 	}
@@ -1564,8 +1562,8 @@ readCleanup:
 		    Tcl_GetString(options.name), format, &block);
 	} else {
 	    result = imageFormat87->fileWriteProc(interp,
-		    Tcl_GetString(options.name), format, &block,
-		    options.metadata);
+		    Tcl_GetString(options.name), format, options.metadata,
+		    &block);
 	}
 	if (options.background) {
 	    Tk_FreeColor(options.background);
@@ -1944,7 +1942,8 @@ ImgPhotoConfigureMaster(
 {
     PhotoInstance *instancePtr;
     const char *oldFileString, *oldPaletteString;
-    Tcl_Obj *oldData, *data = NULL, *oldFormat, *format = NULL, *metadata = NULL;
+    Tcl_Obj *oldData, *data = NULL, *oldFormat, *format = NULL,
+	    *metadataIn = NULL, *metadataOut = NULL;
     Tcl_Obj *tempdata, *tempformat;
     TkSizeT length;
     int i, j, result, imageWidth, imageHeight, oldformat;
@@ -1953,6 +1952,8 @@ ImgPhotoConfigureMaster(
     Tk_PhotoImageFormat *imageFormat;
     Tk_PhotoImageFormat87 *imageFormat87;
     const char **args;
+    Tcl_DString driverInternalDString;
+    int closeChannel;
 
     args = (const char **)ckalloc((objc + 1) * sizeof(char *));
     for (i = 0, j = 0; i < objc; i++,j++) {
@@ -1987,7 +1988,7 @@ ImgPhotoConfigureMaster(
 	    } else if ((args[j][1] == 'm') &&
 		!strncmp(args[j], "-metadata", length)) {
 		if (++i < objc) {
-		    metadata = objv[i];
+		    metadataIn = objv[i];
 		    j--;
 		} else {
 		    ckfree(args);
@@ -2002,6 +2003,12 @@ ImgPhotoConfigureMaster(
     }
 
     /*
+     * Prepare memory connection between format match and read function
+     */
+
+    Tcl_DStringInit(&driverInternalDString);
+
+    /*
      * Save the current values for fileString and dataString, so we can tell
      * if the user specifies them anew. IMPORTANT: if the format changes we
      * have to interpret "-file" and "-data" again as well! It might be that
@@ -2078,29 +2085,30 @@ ImgPhotoConfigureMaster(
 	}
 	masterPtr->format = format;
     }
-    if (metadata) {
+    if (metadataIn) {
 	/*
 	 * make -metadata a dict and take it if keys in.
 	 * Otherwise set a metadata null pointer.
 	 */
 	int dictSize;
 
-	if (TCL_OK != Tcl_DictObjSize(interp,metadata, &dictSize)) {
+	if (TCL_OK != Tcl_DictObjSize(interp,metadataIn, &dictSize)) {
 	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
 		    "value for \"-metadata\" not a dict", -1));
 	    Tcl_SetErrorCode(interp, "TK", "IMAGE", "PHOTO",
 		    "UNRECOGNIZED_DATA", NULL);
 	    return TCL_ERROR;
 	}
+
 	if (dictSize > 0) {
-	    Tcl_IncrRefCount(metadata);
+	    Tcl_IncrRefCount(metadataIn);
 	} else {
-	    metadata = NULL;
+	    metadataIn = NULL;
 	}
 	if (masterPtr->metadata) {
 	    Tcl_DecrRefCount(masterPtr->metadata);
 	}
-	masterPtr->metadata = metadata;
+	masterPtr->metadata = metadataIn;
     }
     /*
      * Set the image to the user-requested size, if any, and make sure storage
@@ -2123,6 +2131,7 @@ ImgPhotoConfigureMaster(
     if ((masterPtr->fileString != NULL)
 	    && ((masterPtr->fileString != oldFileString)
 	    || (masterPtr->format != oldFormat))) {
+
 	/*
 	 * Prevent file system access in a safe interpreter.
 	 */
@@ -2141,6 +2150,8 @@ ImgPhotoConfigureMaster(
 	    goto errorExit;
 	}
 
+	closeChannel = 0;
+
 	/*
 	 * -translation binary also sets -encoding binary
 	 */
@@ -2148,9 +2159,10 @@ ImgPhotoConfigureMaster(
 	if ((Tcl_SetChannelOption(interp, chan,
 		"-translation", "binary") != TCL_OK) ||
 		(MatchFileFormat(interp, chan, masterPtr->fileString,
-			masterPtr->format, &(masterPtr->metadata),
+			masterPtr->format, masterPtr->metadata, NULL,
 			&imageFormat, &imageFormat87,
-			&imageWidth, &imageHeight, &oldformat) != TCL_OK)) {
+			&imageWidth, &imageHeight, &oldformat, &closeChannel,
+			&driverInternalDString) != TCL_OK)) {
 	    Tcl_Close(NULL, chan);
 	    goto errorExit;
 	}
@@ -2173,10 +2185,10 @@ ImgPhotoConfigureMaster(
 		    0, 0, imageWidth, imageHeight, 0, 0);
 	} else {
 	    result = imageFormat87->fileReadProc(interp, chan,
-		    masterPtr->fileString, tempformat,
+		    masterPtr->fileString, tempformat, masterPtr->metadata,
 		    (Tk_PhotoHandle) masterPtr,
 		    0, 0, imageWidth, imageHeight, 0, 0,
-		    &(masterPtr->metadata));
+		    metadataOut, &driverInternalDString);
 	}
 	Tcl_Close(NULL, chan);
 	if (result != TCL_OK) {
@@ -2196,9 +2208,9 @@ ImgPhotoConfigureMaster(
 		    || (masterPtr->format != oldFormat))) {
 
 	if (MatchStringFormat(interp, masterPtr->dataString,
-		masterPtr->format, &(masterPtr->metadata),
+		masterPtr->format, masterPtr->metadata, NULL,
 		&imageFormat, &imageFormat87, &imageWidth,
-		&imageHeight, &oldformat) != TCL_OK) {
+		&imageHeight, &oldformat, &driverInternalDString) != TCL_OK) {
 	    goto errorExit;
 	}
 	if (ImgPhotoSetSize(masterPtr, imageWidth, imageHeight) != TCL_OK) {
@@ -2222,9 +2234,18 @@ ImgPhotoConfigureMaster(
 		goto errorExit;
 	    }
 	} else {
+	    
+	    /*
+	     * Flag that we want the metadata result dict
+	     */
+
+	    metadataOut = Tcl_NewDictObj();
+	    Tcl_IncrRefCount(metadataOut);
+
 	    if (imageFormat87->stringReadProc(interp, tempdata, tempformat,
-		    (Tk_PhotoHandle) masterPtr, 0, 0, imageWidth, imageHeight,
-		    0, 0, &(masterPtr->metadata)) != TCL_OK) {
+		    masterPtr->metadata, (Tk_PhotoHandle) masterPtr, 0, 0,
+		    imageWidth, imageHeight, 0, 0, metadataOut,
+		    &driverInternalDString) != TCL_OK) {
 		goto errorExit;
 	    }
 	}
@@ -2234,6 +2255,48 @@ ImgPhotoConfigureMaster(
     }
 
     /*
+     * Merge driver returned metadata and master metadata
+     */
+    if (metadataOut != NULL) {
+	int dictSize;
+	if (TCL_OK != Tcl_DictObjSize(interp,metadataOut, &dictSize)) {
+	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		    "driver metadata not a dict", -1));
+	    Tcl_SetErrorCode(interp, "TK", "IMAGE", "PHOTO",
+		    "UNRECOGNIZED_DATA", NULL);
+	    goto errorExit;
+	}
+	if (dictSize > 0) {
+
+	    /*
+	     * We have driver return metadata
+	     */
+	    
+	    if (masterPtr->metadata == NULL) {
+		masterPtr->metadata = metadataOut;
+		metadataOut = NULL;
+	    } else {
+		Tcl_DictSearch search;
+		Tcl_Obj *key, *value;
+		int done;
+
+		if (Tcl_IsShared(masterPtr->metadata)) {
+		    masterPtr->metadata = Tcl_DuplicateObj(masterPtr->metadata);
+		    Tcl_IncrRefCount(masterPtr->metadata);
+		}
+
+		if (Tcl_DictObjFirst(interp, metadataOut, &search, &key, &value,
+			&done) != TCL_OK) {
+		    goto errorExit;
+		}
+		for (; !done ; Tcl_DictObjNext(&search, &key, &value, &done)) {
+		    Tcl_DictObjPut(interp, masterPtr->metadata, key, value);
+		}
+	    }
+	}
+    }
+    
+    /*
      * Enforce a reasonable value for gamma.
      */
 
@@ -2265,24 +2328,32 @@ ImgPhotoConfigureMaster(
 	    masterPtr->height, masterPtr->width, masterPtr->height);
     masterPtr->flags &= ~IMAGE_CHANGED;
 
+    Tcl_DStringInit(&driverInternalDString);
     if (oldData != NULL) {
 	Tcl_DecrRefCount(oldData);
     }
     if (oldFormat != NULL) {
 	Tcl_DecrRefCount(oldFormat);
     }
+    if (metadataOut != NULL) {
+	Tcl_DecrRefCount(metadataOut);
+    }
 
     ToggleComplexAlphaIfNeeded(masterPtr);
 
     return TCL_OK;
 
   errorExit:
+    Tcl_DStringInit(&driverInternalDString);
     if (oldData != NULL) {
 	Tcl_DecrRefCount(oldData);
     }
     if (oldFormat != NULL) {
 	Tcl_DecrRefCount(oldFormat);
     }
+    if (metadataOut != NULL) {
+	Tcl_DecrRefCount(metadataOut);
+    }
     return TCL_ERROR;
 }
 
@@ -2635,7 +2706,8 @@ MatchFileFormat(
     Tcl_Channel chan,		/* The image file, open for reading. */
     const char *fileName,	/* The name of the image file. */
     Tcl_Obj *formatObj,		/* User-specified format string, or NULL. */
-    Tcl_Obj **metadataObjPtr,	/* User-specified metadata and return it */
+    Tcl_Obj *metadataInObj,	/* User-specified metadata, may be NULL */
+    Tcl_Obj *metadataOutObj,	/* metadata to return, may be NULL */
     Tk_PhotoImageFormat **imageFormatPtr,
 				/* A pointer to the photo image format record
 				 * is returned here. For format87, this is set
@@ -2647,7 +2719,10 @@ MatchFileFormat(
     int *widthPtr, int *heightPtr,
 				/* The dimensions of the image are returned
 				 * here. */
-    int *oldformat)		/* Returns 1 if the old image API is used. */
+    int *oldformat,		/* Returns 1 if the old image API is used. */
+    int *closeChannelPtr,    	/* Is set to 1 if channel can be closed */
+    Tcl_DString *driverInternalPtr)/* Memory to be passed to the corresponding
+				 * ReadFileFormat function */
 {
     int matched = 0, useoldformat = 0, use87format = 0;
     Tk_PhotoImageFormat *formatPtr;
@@ -2769,8 +2844,9 @@ MatchFileFormat(
 	if (format87Ptr->fileMatchProc != NULL) {
 	    (void) Tcl_Seek(chan, Tcl_LongAsWide(0L), SEEK_SET);
 
-	    if (format87Ptr->fileMatchProc(chan, fileName, formatObj,
-		    widthPtr, heightPtr, interp, metadataObjPtr)) {
+	    if (format87Ptr->fileMatchProc(interp, chan, fileName, formatObj,
+		    metadataInObj, widthPtr, heightPtr, closeChannelPtr,
+		    driverInternalPtr)) {
 		if (*widthPtr < 1) {
 		    *widthPtr = 1;
 		}
@@ -2833,7 +2909,8 @@ MatchStringFormat(
     Tcl_Interp *interp,		/* Interpreter to use for reporting errors. */
     Tcl_Obj *data,		/* Object containing the image data. */
     Tcl_Obj *formatObj,		/* User-specified format string, or NULL. */
-    Tcl_Obj **metadataObjPtr,	/* User-specified metadata and return it */
+    Tcl_Obj *metadataInObj,	/* User-specified metadata, may be NULL */
+    Tcl_Obj *metadataOutObj,	/* metadata output dict, may be NULL */
     Tk_PhotoImageFormat **imageFormatPtr,
 				/* A pointer to the photo image format record
 				 * is returned here. For format87, this is set
@@ -2845,7 +2922,9 @@ MatchStringFormat(
     int *widthPtr, int *heightPtr,
 				/* The dimensions of the image are returned
 				 * here. */
-    int *oldformat)		/* Returns 1 if the old image API is used. */
+    int *oldformat,		/* Returns 1 if the old image API is used. */
+    Tcl_DString *driverInternalPtr)/* Memory to be passed to the corresponding
+				 * ReadFileFormat function */
 {
     int matched = 0, useoldformat = 0, use87format = 0;
     Tk_PhotoImageFormat *formatPtr, *defaultFormatPtr = NULL;
@@ -2959,15 +3038,15 @@ MatchStringFormat(
 	    }
 	    if ((format87Ptr->stringMatchProc != NULL)
 		    && (format87Ptr->stringReadProc != NULL)
-		    && format87Ptr->stringMatchProc(
-                            data, formatObj,
-			    widthPtr, heightPtr, interp, metadataObjPtr)) {
+		    && format87Ptr->stringMatchProc(interp, data, formatObj,
+			    metadataInObj, widthPtr, heightPtr,
+			    driverInternalPtr)) {
 		break;
 	    }
 	}
     }
 
-    if (formatPtr == NULL && format87Ptr == 0) {
+    if (formatPtr == NULL && format87Ptr == NULL) {
 	/*
 	 * Try the default format as last resort (only if no -format option
 	 * was passed).
@@ -4085,72 +4164,6 @@ Tk_PhotoSetSize(
 /*
  *----------------------------------------------------------------------
  *
- * Tk_PhotoGetMetadata --
- *
- *	This function is called to obtain the metadata object of a photo
- *	image.
- *
- * Results:
- *	The image's metadata object pointer.
- *
- * Side effects:
- *	None.
- *
- *----------------------------------------------------------------------
- */
-
-Tcl_Obj *
-Tk_PhotoGetMetadata(
-    Tk_PhotoHandle handle)	/* Handle for the image whose dimensions are
-				 * requested. */
-{
-    PhotoMaster *masterPtr = (PhotoMaster *) handle;
-
-    return masterPtr->metadata;
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * Tk_PhotoSetMetadata --
- *
- *	This function is called to obtain to set the metadata object of a
- *	photo image.
- *
- * Results:
- *	None
- *
- * Side effects:
- *	None.
- *
- *----------------------------------------------------------------------
- */
-
-void
-Tk_PhotoSetMetadata(
-    Tk_PhotoHandle handle,	/* Handle for the image whose dimensions are
-				 * requested. */
-    Tcl_Obj *metadata)
-{
-    PhotoMaster *masterPtr = (PhotoMaster *) handle;
-    /*
-     * Free current object if present
-     */
-    if(masterPtr->metadata != NULL) {
-	Tcl_DecrRefCount(masterPtr->metadata);
-    }
-    /*
-     * Increment ref count of new object to get it
-     */
-    if (metadata != NULL) {
-	Tcl_IncrRefCount(metadata);
-    }
-    masterPtr->metadata = metadata;
-}
-
-/*
- *----------------------------------------------------------------------
- *
  * TkGetPhotoValidRegion --
  *
  *	This function is called to get the part of the photo where there is
diff --git a/generic/tkStubInit.c b/generic/tkStubInit.c
index 461ca1e..e52d404 100644
--- a/generic/tkStubInit.c
+++ b/generic/tkStubInit.c
@@ -1301,8 +1301,7 @@ const TkStubs tkStubs = {
     Tk_Interp, /* 271 */
     Tk_CreateOldImageType, /* 272 */
     Tk_CreateOldPhotoImageFormat, /* 273 */
-    Tk_PhotoGetMetadata, /* 274 */
-    Tk_PhotoSetMetadata, /* 275 */
+    Tk_CreatePhotoImageFormat87 /* 274 */
 };
 
 /* !END!: Do not edit above this line. */