tkImgGIF.c was not following the Tcl C style; fixed...

2 files changed, 681 insertions, 571 deletions

diff --git a/ChangeLog b/ChangeLog
index cfbac8c..22e0e83 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2002-02-19  Donal K. Fellows  <fellowsd@cs.man.ac.uk>
+
+	* generic/tkImgGIF.c: Made file meet the formatting rules from the
+	Tcl Engineering Manual better; mostly differences in whitespace.
+
 2002-02-18  Jeff Hobbs  <jeffh@ActiveState.com>
 
 	* unix/configure: regen'd
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c
index 5b79558..6fe4ed9 100644
--- a/generic/tkImgGIF.c
+++ b/generic/tkImgGIF.c
@@ -19,17 +19,17 @@
  * This file also contains code from the giftoppm program, which is
  * copyrighted as follows:
  *
- * +-------------------------------------------------------------------+
- * | Copyright 1990, David Koblas.                                     |
- * |   Permission to use, copy, modify, and distribute this software   |
- * |   and its documentation for any purpose and without fee is hereby |
- * |   granted, provided that the above copyright notice appear in all |
- * |   copies and that both that copyright notice and this permission  |
- * |   notice appear in supporting documentation.  This software is    |
- * |   provided "as is" without express or implied warranty.           |
+ * +--------------------------------------------------------------------+
+ * | Copyright 1990, David Koblas.					|
+ * |   Permission to use, copy, modify, and distribute this software	|
+ * |   and its documentation for any purpose and without fee is hereby	|
+ * |   granted, provided that the above copyright notice appear in all	|
+ * |   copies and that both that copyright notice and this permission	|
+ * |   notice appear in supporting documentation.  This software is	|
+ * |   provided "as is" without express or implied warranty.		|
  * +-------------------------------------------------------------------+
  *
- * RCS: @(#) $Id: tkImgGIF.c,v 1.19 2002/01/17 05:13:11 dgp Exp $
+ * RCS: @(#) $Id: tkImgGIF.c,v 1.20 2002/02/19 14:05:43 dkf Exp $
  */
 
 /*
@@ -41,7 +41,7 @@
  * Any other invalid character is treated as an EOF
  */
 
-#define GIF_SPECIAL	 (256)
+#define GIF_SPECIAL	(256)
 #define GIF_PAD		(GIF_SPECIAL+1)
 #define GIF_SPACE	(GIF_SPECIAL+2)
 #define GIF_BAD		(GIF_SPECIAL+3)
@@ -72,13 +72,15 @@ typedef struct mFile {
  * encoding independant.
  */
 
-static CONST char GIF87a[] =
-	{ 0x47, 0x49, 0x46, 0x38, 0x37, 0x61, 0x00 }; /* ASCII GIF87a */
-static CONST char GIF89a[] =
-	{ 0x47, 0x49, 0x46, 0x38, 0x39, 0x61, 0x00 }; /* ASCII GIF89a */
-#  define GIF_TERMINATOR 0x3b                         /* ASCII ; */
-#  define GIF_EXTENSION  0x21                         /* ASCII ! */
-#  define GIF_START      0x2c                         /* ASCII , */
+static CONST char GIF87a[] = {			/* ASCII GIF87a */
+    0x47, 0x49, 0x46, 0x38, 0x37, 0x61, 0x00
+};
+static CONST char GIF89a[] = {			/* ASCII GIF89a */
+    0x47, 0x49, 0x46, 0x38, 0x39, 0x61, 0x00
+};
+#  define GIF_TERMINATOR 0x3b			/* ASCII ; */
+#  define GIF_EXTENSION  0x21			/* ASCII ! */
+#  define GIF_START	 0x2c			/* ASCII , */
 
 /*
  * 			 HACK ALERT!!  HACK ALERT!!  HACK ALERT!!
@@ -96,10 +98,10 @@ static Tcl_ThreadDataKey dataKey;
  * The format record for the GIF file format:
  */
 
-static int      FileMatchGIF _ANSI_ARGS_((Tcl_Channel chan, CONST char *fileName,
+static int	FileMatchGIF _ANSI_ARGS_((Tcl_Channel chan, CONST char *fileName,
 		    Tcl_Obj *format, int *widthPtr, int *heightPtr,
 		    Tcl_Interp *interp));
-static int      FileReadGIF  _ANSI_ARGS_((Tcl_Interp *interp,
+static int	FileReadGIF  _ANSI_ARGS_((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));
@@ -118,13 +120,13 @@ static int	CommonWriteGIF _ANSI_ARGS_((Tcl_Interp *interp,
 		    Tk_PhotoImageBlock *blockPtr));
 
 Tk_PhotoImageFormat tkImgFmtGIF = {
-	"gif",			/* name */
-	FileMatchGIF,   /* fileMatchProc */
-	StringMatchGIF, /* stringMatchProc */
-	FileReadGIF,    /* fileReadProc */
-	StringReadGIF,  /* stringReadProc */
-	FileWriteGIF,   /* fileWriteProc */
-	NULL,           /* stringWriteProc */
+    "gif",		/* name */
+    FileMatchGIF,	/* fileMatchProc */
+    StringMatchGIF,	/* stringMatchProc */
+    FileReadGIF,	/* fileReadProc */
+    StringReadGIF,	/* stringReadProc */
+    FileWriteGIF,	/* fileWriteProc */
+    NULL,		/* stringWriteProc */
 };
 
 #define INTERLACE		0x40
@@ -136,7 +138,7 @@ Tk_PhotoImageFormat tkImgFmtGIF = {
 #define CM_BLUE			2
 #define CM_ALPHA		3
 #define MAX_LWZ_BITS		12
-#define LM_to_uint(a,b)         (((b)<<8)|(a))
+#define LM_to_uint(a,b)		(((b)<<8)|(a))
 #define ReadOK(file,buffer,len)	(Fread(buffer, len, 1, file) != 0)
 
 /*
@@ -288,7 +290,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY,
     }
     bitPixel = 2<<(buf[0]&0x07);
 
-    if (BitSet(buf[0], LOCALCOLORMAP)) {    /* Global Colormap */
+    if (BitSet(buf[0], LOCALCOLORMAP)) {	/* Global Colormap */
 	if (!ReadColorMap(chan, bitPixel, colorMap)) {
 	    Tcl_AppendResult(interp, "error reading color map",
 		    (char *) NULL);
@@ -378,7 +380,9 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY,
 	bitPixel = 1<<((buf[8]&0x07)+1);
 
 	if (index--) {
-	    /* this is not the image we want to read: skip it. */
+	    /*
+	     * This is not the image we want to read: skip it.
+	     */
 	    if (BitSet(buf[8], LOCALCOLORMAP)) {
 		if (!ReadColorMap(chan, bitPixel, colorMap)) {
 		    Tcl_AppendResult(interp,
@@ -387,7 +391,9 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY,
 		}
 	    }
 
-	    /* If we've not yet allocated a trash buffer, do so now */
+	    /*
+	     * If we've not yet allocated a trash buffer, do so now.
+	     */
 	    if (trashBuffer == NULL) {
 		nBytes = fileWidth * fileHeight * 3;
 		trashBuffer =
@@ -395,28 +401,32 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY,
 	    }
 
 	    /*
-	     * Slurp!  Process the data for this image and stuff it in a
-	     * trash buffer.
+	     * Slurp!  Process the data for this image and stuff it in
+	     * a trash buffer.
 	     *
-	     * Yes, it might be more efficient here to *not* store the data
-	     * (we're just going to throw it away later).  However, I elected
-	     * to implement it this way for good reasons.  First, I wanted to
-	     * avoid duplicating the (fairly complex) LWZ decoder in ReadImage.
-	     * Fine, you say, why didn't you just modify it to allow the use of
-	     * a NULL specifier for the output buffer?  I tried that, but it
-	     * negatively impacted the performance of what I think will be the
-	     * common case:  reading the first image in the file.  Rather than
-	     * marginally improve the speed of the less frequent case, I chose
-	     * to maintain high performance for the common case.
+	     * Yes, it might be more efficient here to *not* store the
+	     * data (we're just going to throw it away later).
+	     * However, I elected to implement it this way for good
+	     * reasons.  First, I wanted to avoid duplicating the
+	     * (fairly complex) LWZ decoder in ReadImage.  Fine, you
+	     * say, why didn't you just modify it to allow the use of
+	     * a NULL specifier for the output buffer?  I tried that,
+	     * but it negatively impacted the performance of what I
+	     * think will be the common case: reading the first image
+	     * in the file.  Rather than marginally improve the speed
+	     * of the less frequent case, I chose to maintain high
+	     * performance for the common case.
 	     */
 	    if (ReadImage(interp, (char *) trashBuffer, chan, fileWidth,
-			  fileHeight, colorMap, 0, 0, 0, 0, 0, -1) != TCL_OK) {
-	      goto error;
+		    fileHeight, colorMap, 0, 0, 0, 0, 0, -1) != TCL_OK) {
+		goto error;
 	    }
 	    continue;
 	}
 
-	/* If a trash buffer has been allocated, free it now */
+	/*
+	 * If a trash buffer has been allocated, free it now.
+	 */
 	if (trashBuffer != NULL) {
 	    ckfree((char *)trashBuffer);
 	    trashBuffer = NULL;
@@ -520,25 +530,31 @@ StringMatchGIF(dataObj, format, widthPtr, heightPtr, interp)
 
     data = Tcl_GetByteArrayFromObj(dataObj, &length);
 
-    /* Header is a minimum of 10 bytes */
+    /*
+     * Header is a minimum of 10 bytes.
+     */
     if (length < 10) {
-      return 0;
+	return 0;
     }
 
-    /* Check whether the data is Base64 encoded */
+    /*
+     * Check whether the data is Base64 encoded.
+     */
 
     if ((strncmp(GIF87a, (char *) data, 6) != 0) && 
-	(strncmp(GIF89a, (char *) data, 6) != 0)) {
-      /* Try interpreting the data as Base64 encoded */
-      mInit((unsigned char *) data, &handle);
-      got = Mread(header, 10, 1, &handle);
-      if (got != 10
-	      || ((strncmp(GIF87a, (char *) header, 6) != 0)
-	      && (strncmp(GIF89a, (char *) header, 6) != 0))) {
-	  return 0;
-      }
+	    (strncmp(GIF89a, (char *) data, 6) != 0)) {
+	/*
+	 * Try interpreting the data as Base64 encoded
+	 */
+	mInit((unsigned char *) data, &handle);
+	got = Mread(header, 10, 1, &handle);
+	if (got != 10
+		|| ((strncmp(GIF87a, (char *) header, 6) != 0)
+		&& (strncmp(GIF89a, (char *) header, 6) != 0))) {
+	    return 0;
+	}
     } else {
-      memcpy((VOID *) header, (VOID *) data, 10);
+	memcpy((VOID *) header, (VOID *) data, 10);
     }
     *widthPtr = LM_to_uint(header[6],header[7]);
     *heightPtr = LM_to_uint(header[8],header[9]);
@@ -574,13 +590,13 @@ StringReadGIF(interp, dataObj, format, imageHandle,
     Tcl_Obj *format;		/* format object, or NULL */
     Tk_PhotoHandle imageHandle;	/* the image to write this data into */
     int destX, destY;		/* The rectangular region of the  */
-    int  width, height;		/*   image to copy */
+    int width, height;		/*   image to copy */
     int srcX, srcY;
 {
     int result;
     MFile handle;
     ThreadSpecificData *tsdPtr = (ThreadSpecificData *) 
-            Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
     Tcl_Channel dataSrc;
     char *data;
 
@@ -588,8 +604,7 @@ StringReadGIF(interp, dataObj, format, imageHandle,
      * Check whether the data is Base64 encoded
      */
     data = (char *) Tcl_GetByteArrayFromObj(dataObj, NULL);
-    if ((strncmp(GIF87a, data, 6) != 0) && 
-	    (strncmp(GIF89a, data, 6) != 0)) {
+    if ((strncmp(GIF87a, data, 6) != 0) && (strncmp(GIF89a, data, 6) != 0)) {
 	mInit((unsigned char *)data, &handle);
 	tsdPtr->fromData = 1;
 	dataSrc = (Tcl_Channel) &handle;
@@ -601,7 +616,7 @@ StringReadGIF(interp, dataObj, format, imageHandle,
     result = FileReadGIF(interp, dataSrc, "inline data",
 	    format, imageHandle, destX, destY, width, height, srcX, srcY);
     tsdPtr->fromData = 0;
-    return(result);
+    return result;
 }
 
 /*
@@ -656,65 +671,65 @@ ReadGIFHeader(chan, widthPtr, heightPtr)
 
 static int
 ReadColorMap(chan, number, buffer)
-     Tcl_Channel chan;
-     int number;
-     unsigned char buffer[MAXCOLORMAPSIZE][4];
+    Tcl_Channel chan;
+    int number;
+    unsigned char buffer[MAXCOLORMAPSIZE][4];
 {
-	int i;
-	unsigned char rgb[3];
+    int i;
+    unsigned char rgb[3];
 
-	for (i = 0; i < number; ++i) {
-	    if (! ReadOK(chan, rgb, sizeof(rgb))) {
-		return 0;
-	    }
-	    
-	    if (buffer) {
-		buffer[i][CM_RED] = rgb[0] ;
-		buffer[i][CM_GREEN] = rgb[1] ;
-		buffer[i][CM_BLUE] = rgb[2] ;
-		buffer[i][CM_ALPHA] = 255 ;
-	    }
+    for (i = 0; i < number; ++i) {
+	if (! ReadOK(chan, rgb, sizeof(rgb))) {
+	    return 0;
+	}
+
+	if (buffer) {
+	    buffer[i][CM_RED] = rgb[0] ;
+	    buffer[i][CM_GREEN] = rgb[1] ;
+	    buffer[i][CM_BLUE] = rgb[2] ;
+	    buffer[i][CM_ALPHA] = 255 ;
 	}
-	return 1;
+    }
+    return 1;
 }
 
 
 
 static int
 DoExtension(chan, label, transparent)
-     Tcl_Channel chan;
-     int label;
-     int *transparent;
+    Tcl_Channel chan;
+    int label;
+    int *transparent;
 {
     static unsigned char buf[256];
     int count;
 
     switch (label) {
-	case 0x01:      /* Plain Text Extension */
-	    break;
-	    
-	case 0xff:      /* Application Extension */
-	    break;
+    case 0x01:		/* Plain Text Extension */
+	break;
 
-	case 0xfe:      /* Comment Extension */
-	    do {
-		count = GetDataBlock(chan, (unsigned char*) buf);
-	    } while (count > 0);
-	    return count;
+    case 0xff:		/* Application Extension */
+	break;
 
-	case 0xf9:      /* Graphic Control Extension */
+    case 0xfe:		/* Comment Extension */
+	do {
 	    count = GetDataBlock(chan, (unsigned char*) buf);
-	    if (count < 0) {
-		return 1;
-	    }
-	    if ((buf[0] & 0x1) != 0) {
-		*transparent = buf[3];
-	    }
+	} while (count > 0);
+	return count;
+
+    case 0xf9:		/* Graphic Control Extension */
+	count = GetDataBlock(chan, (unsigned char*) buf);
+	if (count < 0) {
+	    return 1;
+	}
+	if ((buf[0] & 0x1) != 0) {
+	    *transparent = buf[3];
+	}
 
-	    do {
-		count = GetDataBlock(chan, (unsigned char*) buf);
-	    } while (count > 0);
-	    return count;
+	do {
+	    count = GetDataBlock(chan, (unsigned char*) buf);
+	} while (count > 0);
+	return count;
     }
 
     do {
@@ -727,8 +742,8 @@ static int ZeroDataBlock = 0;
 
 static int
 GetDataBlock(chan, buf)
-     Tcl_Channel chan;
-     unsigned char *buf;
+    Tcl_Channel chan;
+    unsigned char *buf;
 {
     unsigned char count;
 
@@ -753,17 +768,17 @@ GetDataBlock(chan, buf)
  * ReadImage --
  *
  *	Process a GIF image from a given source, with a given height,
- *      width, transparency, etc.
+ *	width, transparency, etc.
  *
- *      This code is based on the code found in the ImageMagick GIF decoder,
- *      which is (c) 2000 ImageMagick Studio.
+ *	This code is based on the code found in the ImageMagick GIF decoder,
+ *	which is (c) 2000 ImageMagick Studio.
  *
- *      Some thoughts on our implementation:
- *      It sure would be nice if ReadImage didn't take 11 parameters!  I think
- *      that if we were smarter, we could avoid doing that.
+ *	Some thoughts on our implementation:
+ *	It sure would be nice if ReadImage didn't take 11 parameters!  I think
+ *	that if we were smarter, we could avoid doing that.
  *
- *      Possible further optimizations:  we could pull the GetCode function
- *      directly into ReadImage, which would improve our speed.
+ *	Possible further optimizations:  we could pull the GetCode function
+ *	directly into ReadImage, which would improve our speed.
  *
  * Results:
  *	Processes a GIF image and loads the pixel data into a memory array.
@@ -777,15 +792,15 @@ GetDataBlock(chan, buf)
 static int
 ReadImage(interp, imagePtr, chan, len, rows, cmap,
 	width, height, srcX, srcY, interlace, transparent)
-     Tcl_Interp *interp;
-     char *imagePtr;
-     Tcl_Channel chan;
-     int len, rows;
-     unsigned char cmap[MAXCOLORMAPSIZE][4];
-     int width, height;
-     int srcX, srcY;
-     int interlace;
-     int transparent;
+    Tcl_Interp *interp;
+    char *imagePtr;
+    Tcl_Channel chan;
+    int len, rows;
+    unsigned char cmap[MAXCOLORMAPSIZE][4];
+    int width, height;
+    int srcX, srcY;
+    int interlace;
+    int transparent;
 {
     unsigned char initialCodeSize;
     int v;
@@ -797,9 +812,9 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
     unsigned char  append[(1 << MAX_LWZ_BITS)];
     unsigned char  stack[(1 << MAX_LWZ_BITS)*2];
     register unsigned char *top;
-    int codeSize, clearCode, inCode, endCode, oldCode, maxCode,
-	code, firstCode;
-    
+    int codeSize, clearCode, inCode, endCode, oldCode, maxCode;
+    int code, firstCode;
+
     /*
      *  Initialize the decoder
      */
@@ -808,7 +823,7 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 		Tcl_PosixError(interp), (char *) NULL);
 	return TCL_ERROR;
     }
-    if (transparent!=-1) {
+    if (transparent != -1) {
 	cmap[transparent][CM_RED] = 0;
 	cmap[transparent][CM_GREEN] = 0;
 	cmap[transparent][CM_BLUE] = 0;
@@ -817,19 +832,21 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 
     pixelPtr = imagePtr;
 
-    /* Initialize the decoder */
-    /* Set values for "special" numbers:
+    /*
+     * Initialize the decoder.
+     *
+     * Set values for "special" numbers:
      * clear code	reset the decoder
      * end code		stop decoding
      * code size	size of the next code to retrieve
      * max code		next available table position
      */
-    clearCode   = 1 << (int) initialCodeSize;
-    endCode     = clearCode + 1;
-    codeSize    = (int) initialCodeSize + 1;
-    maxCode     = clearCode + 2;
-    oldCode     = -1;
-    firstCode   = -1;
+    clearCode = 1 << (int) initialCodeSize;
+    endCode = clearCode + 1;
+    codeSize = (int) initialCodeSize + 1;
+    maxCode = clearCode + 2;
+    oldCode = -1;
+    firstCode = -1;
     
     memset((void *)prefix, 0, (1 << MAX_LWZ_BITS) * sizeof(short));
     memset((void *)append, 0, (1 << MAX_LWZ_BITS) * sizeof(char));
@@ -840,12 +857,16 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 
     GetCode(chan, 0, 1);
 
-    /* Read until we finish the image */
+    /*
+     * Read until we finish the image
+     */
     for (i = 0, ypos = 0; i < rows; i++) {
 	for (xpos = 0; xpos < len; ) {
 
 	    if (top == stack) {
-		/* Bummer -- our stack is empty.  Now we have to work! */
+		/*
+		 * Bummer -- our stack is empty.  Now we have to work!
+		 */
 		code = GetCode(chan, codeSize, 0);
 		if (code < 0) {
 		    return TCL_OK;
@@ -864,10 +885,12 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 		}
 
 		if (code == clearCode) {
-		    /* Reset the decoder */
-		    codeSize    = initialCodeSize + 1;
-		    maxCode     = clearCode + 2;
-		    oldCode     = -1;
+		    /*
+		     * Reset the decoder.
+		     */
+		    codeSize = initialCodeSize + 1;
+		    maxCode = clearCode + 2;
+		    oldCode = -1;
 		    continue;
 		}
 		
@@ -880,7 +903,7 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 		     * roll this into the clearCode test above, because
 		     * at that point we have not yet read the next code.
 		     */
-		    *top++=append[code];
+		    *top++ = append[code];
 		    oldCode = code;
 		    firstCode = code;
 		    continue;
@@ -916,15 +939,20 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 		    return TCL_OK;
 		}
 
-		/* Push the head of the string onto the stack */
+		/*
+		 * Push the head of the string onto the stack.
+		 */
 		*top++ = firstCode;
 
-		/* Add a new string to the string table */
+		/*
+		 * Add a new string to the string table
+		 */
 		prefix[maxCode] = oldCode;
 		append[maxCode] = firstCode;
 		maxCode++;
 
-		/* maxCode tells us the maximum code value we can accept.
+		/*
+		 * maxCode tells us the maximum code value we can accept.
 		 * If we see that we need more bits to represent it than
 		 * we are requesting from the unpacker, we need to increase
 		 * the number we ask for.
@@ -936,7 +964,9 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 		oldCode = inCode;
 	    }
 
-	    /* Pop the next color index off the stack */
+	    /*
+	     * Pop the next color index off the stack.
+	     */
 	    v = *(--top);
 	    if (v < 0) {
 		return TCL_OK;
@@ -957,7 +987,9 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 
 	}
 
-	/* If interlacing, the next ypos is not just +1 */
+	/*
+	 * If interlacing, the next ypos is not just +1
+	 */
 	if (interlace) {
 	    ypos += interlaceStep[pass];
 	    while (ypos >= height) {
@@ -981,23 +1013,23 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
  *
  * GetCode --
  *
- *      Extract the next compression code from the file.  In GIF's, the
- *      compression codes are between 3 and 12 bits long and are then
- *      packed into 8 bit bytes, left to right, for example:
- *                 bbbaaaaa
- *                 dcccccbb
- *                 eeeedddd
- *                 ...
- *      We use a byte buffer read from the file and a sliding window
- *      to unpack the bytes.  Thanks to ImageMagick for the sliding window
- *      idea.
- *      args:  chan         the channel to read from
- *             code_size    size of the code to extract
- *             flag         boolean indicating whether the extractor
- *                          should be reset or not
+ *	Extract the next compression code from the file.  In GIF's, the
+ *	compression codes are between 3 and 12 bits long and are then
+ *	packed into 8 bit bytes, left to right, for example:
+ *		bbbaaaaa
+ *		dcccccbb
+ *		eeeedddd
+ *		...
+ *	We use a byte buffer read from the file and a sliding window
+ *	to unpack the bytes.  Thanks to ImageMagick for the sliding window
+ *	idea.
+ *	args:  chan	    the channel to read from
+ *	       code_size    size of the code to extract
+ *	       flag	    boolean indicating whether the extractor
+ *			    should be reset or not
  *
  * Results:
- *	code                the next compression code
+ *	code		    the next compression code
  *
  * Side effects:
  *	May consume more input from chan.
@@ -1007,9 +1039,9 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap,
 
 static int
 GetCode(chan, code_size, flag)
-     Tcl_Channel chan;
-     int code_size;
-     int flag;
+    Tcl_Channel chan;
+    int code_size;
+    int flag;
 {
     static unsigned char buf[280];
     static int bytes = 0, done;
@@ -1020,7 +1052,9 @@ GetCode(chan, code_size, flag)
     int ret;
     
     if (flag) {
-	/* Initialize the decoder */
+	/*
+	 * Initialize the decoder.
+	 */
 	bitsInWindow = 0;
 	bytes = 0;
 	window = 0;
@@ -1030,12 +1064,16 @@ GetCode(chan, code_size, flag)
     }
 
     while (bitsInWindow < code_size) {
-	/* Not enough bits in our window to cover the request */
+	/*
+	 * Not enough bits in our window to cover the request.
+	 */
 	if (done) {
 	    return -1;
 	}
 	if (bytes == 0) {
-	    /* Not enough bytes in our buffer to add to the window */
+	    /*
+	     * Not enough bytes in our buffer to add to the window.
+	     */
 	    bytes = GetDataBlock(chan, buf);
 	    c = buf;
 	    if (bytes <= 0) {
@@ -1043,7 +1081,9 @@ GetCode(chan, code_size, flag)
 		break;
 	    }
 	}
-	/* Tack another byte onto the window, see if that's enough */
+	/*
+	 * Tack another byte onto the window, see if that's enough.
+	 */
 	window += (*c) << bitsInWindow;
 	c++;
 	bitsInWindow += 8;
@@ -1051,10 +1091,14 @@ GetCode(chan, code_size, flag)
     }
 
 
-    /* The next code will always be the last code_size bits of the window */
+    /*
+     * The next code will always be the last code_size bits of the window.
+     */
     ret = window & ((1 << code_size) - 1);
     
-    /* Shift data in the window to put the next code at the end */
+    /*
+     * Shift data in the window to put the next code at the end.
+     */
     window >>= code_size;
     bitsInWindow -= code_size;
     return ret;
@@ -1144,20 +1188,20 @@ Mread(dst, chunkSize, numChunks, handle)
 
 static int
 Mgetc(handle)
-   MFile *handle;		/* Handle containing decoder data and state. */
+   MFile *handle;		/* Handle containing decoder data and state */
 {
     int c;
     int result = 0;		/* Initialization needed only to prevent
 				 * gcc compiler warning. */
-     
+
     if (handle->state == GIF_DONE) {
-	return(GIF_DONE);
+	return GIF_DONE;
     }
 
     do {
 	c = char64(*handle->data);
 	handle->data++;
-    } while (c==GIF_SPACE);
+    } while (c == GIF_SPACE);
 
     if (c>GIF_SPECIAL) {
 	handle->state = GIF_DONE;
@@ -1165,24 +1209,24 @@ Mgetc(handle)
     }
 
     switch (handle->state++) {
-	case 0:
-	   handle->c = c<<2;
-	   result = Mgetc(handle);
-	   break;
-	case 1:
-	   result = handle->c | (c>>4);
-	   handle->c = (c&0xF)<<4;
-	   break;
-	case 2:
-	   result = handle->c | (c>>2);
-	   handle->c = (c&0x3) << 6;
-	   break;
-	case 3:
-	   result = handle->c | c;
-	   handle->state = 0;
-	   break;
-    }
-    return(result);
+    case 0:
+	handle->c = c<<2;
+	result = Mgetc(handle);
+	break;
+    case 1:
+	result = handle->c | (c>>4);
+	handle->c = (c&0xF)<<4;
+	break;
+    case 2:
+	result = handle->c | (c>>2);
+	handle->c = (c&0x3) << 6;
+	break;
+    case 3:
+	result = handle->c | c;
+	handle->state = 0;
+	break;
+    }
+    return result;
 }
 
 /*
@@ -1207,33 +1251,37 @@ char64(c)
 int c;
 {
     switch(c) {
-        case 'A': return(0);  case 'B': return(1);  case 'C': return(2);
-        case 'D': return(3);  case 'E': return(4);  case 'F': return(5);
-        case 'G': return(6);  case 'H': return(7);  case 'I': return(8);
-        case 'J': return(9);  case 'K': return(10); case 'L': return(11);
-        case 'M': return(12); case 'N': return(13); case 'O': return(14);
-        case 'P': return(15); case 'Q': return(16); case 'R': return(17);
-        case 'S': return(18); case 'T': return(19); case 'U': return(20);
-        case 'V': return(21); case 'W': return(22); case 'X': return(23);
-        case 'Y': return(24); case 'Z': return(25); case 'a': return(26);
-        case 'b': return(27); case 'c': return(28); case 'd': return(29);
-        case 'e': return(30); case 'f': return(31); case 'g': return(32);
-        case 'h': return(33); case 'i': return(34); case 'j': return(35);
-        case 'k': return(36); case 'l': return(37); case 'm': return(38);
-        case 'n': return(39); case 'o': return(40); case 'p': return(41);
-        case 'q': return(42); case 'r': return(43); case 's': return(44);
-        case 't': return(45); case 'u': return(46); case 'v': return(47);
-        case 'w': return(48); case 'x': return(49); case 'y': return(50);
-        case 'z': return(51); case '0': return(52); case '1': return(53);
-        case '2': return(54); case '3': return(55); case '4': return(56);
-        case '5': return(57); case '6': return(58); case '7': return(59);
-        case '8': return(60); case '9': return(61); case '+': return(62);
-        case '/': return(63);
-
-	case ' ': case '\t': case '\n': case '\r': case '\f': return(GIF_SPACE);
-	case '=':  return(GIF_PAD);
-	case '\0': return(GIF_DONE);
-	default: return(GIF_BAD);
+    case 'A': return 0;  case 'B': return 1;  case 'C': return 2;
+    case 'D': return 3;  case 'E': return 4;  case 'F': return 5;
+    case 'G': return 6;  case 'H': return 7;  case 'I': return 8;
+    case 'J': return 9;  case 'K': return 10; case 'L': return 11;
+    case 'M': return 12; case 'N': return 13; case 'O': return 14;
+    case 'P': return 15; case 'Q': return 16; case 'R': return 17;
+    case 'S': return 18; case 'T': return 19; case 'U': return 20;
+    case 'V': return 21; case 'W': return 22; case 'X': return 23;
+    case 'Y': return 24; case 'Z': return 25; case 'a': return 26;
+    case 'b': return 27; case 'c': return 28; case 'd': return 29;
+    case 'e': return 30; case 'f': return 31; case 'g': return 32;
+    case 'h': return 33; case 'i': return 34; case 'j': return 35;
+    case 'k': return 36; case 'l': return 37; case 'm': return 38;
+    case 'n': return 39; case 'o': return 40; case 'p': return 41;
+    case 'q': return 42; case 'r': return 43; case 's': return 44;
+    case 't': return 45; case 'u': return 46; case 'v': return 47;
+    case 'w': return 48; case 'x': return 49; case 'y': return 50;
+    case 'z': return 51; case '0': return 52; case '1': return 53;
+    case '2': return 54; case '3': return 55; case '4': return 56;
+    case '5': return 57; case '6': return 58; case '7': return 59;
+    case '8': return 60; case '9': return 61; case '+': return 62;
+    case '/': return 63;
+
+    case ' ': case '\t': case '\n': case '\r': case '\f':
+	return GIF_SPACE;
+    case '=':
+	return GIF_PAD;
+    case '\0':
+	return GIF_DONE;
+    default:
+	return GIF_BAD;
     }
 }
 
@@ -1257,18 +1305,18 @@ Fread(dst, hunk, count, chan)
     Tcl_Channel chan;
 {
     ThreadSpecificData *tsdPtr = (ThreadSpecificData *) 
-            Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
+	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
     MFile *handle;
 
     switch (tsdPtr->fromData) {
-      case 1:
-	return(Mread(dst, hunk, count, (MFile *) chan));
-      case 2:
+    case 1:
+	return Mread(dst, hunk, count, (MFile *) chan);
+    case 2:
 	handle = (MFile *) chan;
 	memcpy((VOID *)dst, (VOID *) handle->data, (size_t) (hunk * count));
 	handle->data += hunk * count;
-	return((int) (hunk * count));
-      default:
+	return (int)(hunk * count);
+    default:
 	return Tcl_Read(chan, (char *) dst, (int) (hunk * count));
     }
 }
@@ -1277,13 +1325,13 @@ Fread(dst, hunk, count, chan)
 /*
  * ChanWriteGIF - writes a image in GIF format.
  *-------------------------------------------------------------------------
- * Author:          		Lolo
- *                              Engeneering Projects Area 
- *	            		Department of Mining 
- *                  		University of Oviedo
+ * Author:			Lolo
+ *				Engeneering Projects Area 
+ *				Department of Mining 
+ *				University of Oviedo
  * e-mail			zz11425958@zeus.etsimo.uniovi.es
- *                  		lolo@pcsig22.etsimo.uniovi.es
- * Date:            		Fri September 20 1996
+ *				lolo@pcsig22.etsimo.uniovi.es
+ * Date:			Fri September 20 1996
  *
  * Modified for transparency handling (gif89a) and miGIF compression
  * by Jan Nijtmans <j.nijtmans@chello.nl>
@@ -1307,11 +1355,11 @@ Fread(dst, hunk, count, chan)
 
 typedef int (* ifunptr) _ANSI_ARGS_((void));	
 
-#define LSB(a)                  ((unsigned char) (((short)(a)) & 0x00FF))
-#define MSB(a)                  ((unsigned char) (((short)(a)) >> 8))
+#define LSB(a)			((unsigned char) (((short)(a)) & 0x00FF))
+#define MSB(a)			((unsigned char) (((short)(a)) >> 8))
 
 #define GIFBITS 12
-#define HSIZE  5003            /* 80% occupancy */
+#define HSIZE  5003		/* 80% occupancy */
 
 static int ssize;
 static int csize;
@@ -1340,7 +1388,7 @@ static void savemap _ANSI_ARGS_((Tk_PhotoImageBlock *blockPtr,
 static int ReadValue _ANSI_ARGS_((void));
 
 static int
-FileWriteGIF (interp, filename, format, blockPtr)
+FileWriteGIF(interp, filename, format, blockPtr)
     Tcl_Interp *interp;		/* Interpreter to use for reporting errors. */
     CONST char	*filename;
     Tcl_Obj	*format;
@@ -1383,9 +1431,9 @@ CommonWriteGIF(interp, handle, format, blockPtr)
     top = 0;
     left = 0;
 
-    pixelSize=blockPtr->pixelSize;
-    greenOffset=blockPtr->offset[1]-blockPtr->offset[0];
-    blueOffset=blockPtr->offset[2]-blockPtr->offset[0];
+    pixelSize = blockPtr->pixelSize;
+    greenOffset = blockPtr->offset[1]-blockPtr->offset[0];
+    blueOffset = blockPtr->offset[2]-blockPtr->offset[0];
     alphaOffset = blockPtr->offset[0];
     if (alphaOffset < blockPtr->offset[2]) {
 	alphaOffset = blockPtr->offset[2];
@@ -1398,30 +1446,32 @@ CommonWriteGIF(interp, handle, format, blockPtr)
 
     Tcl_Write(handle, (char *) (alphaOffset ? GIF89a : GIF87a), 6);
 
-    for (x=0;x<MAXCOLORMAPSIZE;x++) {
+    for (x=0 ; x<MAXCOLORMAPSIZE ; x++) {
 	mapa[x][CM_RED] = 255;
 	mapa[x][CM_GREEN] = 255;
 	mapa[x][CM_BLUE] = 255;
     }
 
 
-    width=blockPtr->width;
-    height=blockPtr->height;
-    pixelo=blockPtr->pixelPtr + blockPtr->offset[0];
-    pixelPitch=blockPtr->pitch;
+    width = blockPtr->width;
+    height = blockPtr->height;
+    pixelo = blockPtr->pixelPtr + blockPtr->offset[0];
+    pixelPitch = blockPtr->pitch;
     savemap(blockPtr,mapa);
-    if (num>=MAXCOLORMAPSIZE) {
+    if (num >= MAXCOLORMAPSIZE) {
 	Tcl_AppendResult(interp, "too many colors", (char *) NULL);
 	return TCL_ERROR;
     }
-    if (num<2) num=2;
-    c=LSB(width);
+    if (num<2) {
+	num = 2;
+    }
+    c = LSB(width);
     Mputc(c,handle);
-    c=MSB(width);
+    c = MSB(width);
     Mputc(c,handle);
-    c=LSB(height);
+    c = LSB(height);
     Mputc(c,handle);
-    c=MSB(height);
+    c = MSB(height);
     Mputc(c,handle);
 
     resolution = 0;
@@ -1433,16 +1483,20 @@ CommonWriteGIF(interp, handle, format, blockPtr)
 
     num = 1 << resolution;
 
-    /*  background color */
+    /*
+     * background color
+     */
 
     c = 0;
     Mputc(c,handle);
 
-    /*  zero for future expansion  */
+    /*
+     * zero for future expansion.
+     */
 
     Mputc(c,handle);
 
-    for (x=0; x<num ;x++) {
+    for (x=0 ; x<num ; x++) {
 	c = mapa[x][CM_RED];
 	Mputc(c,handle);
 	c = mapa[x][CM_GREEN];
@@ -1463,28 +1517,28 @@ CommonWriteGIF(interp, handle, format, blockPtr)
 
     c = GIF_START;
     Mputc(c,handle);
-    c=LSB(top);
+    c = LSB(top);
     Mputc(c,handle);
-    c=MSB(top);
+    c = MSB(top);
     Mputc(c,handle);
-    c=LSB(left);
+    c = LSB(left);
     Mputc(c,handle);
-    c=MSB(left);
+    c = MSB(left);
     Mputc(c,handle);
 
-    c=LSB(width);
+    c = LSB(width);
     Mputc(c,handle);
-    c=MSB(width);
+    c = MSB(width);
     Mputc(c,handle);
 
-    c=LSB(height);
+    c = LSB(height);
     Mputc(c,handle);
-    c=MSB(height);
+    c = MSB(height);
     Mputc(c,handle);
 
-    c=0;
+    c = 0;
     Mputc(c,handle);
-    c=resolution;
+    c = resolution;
     Mputc(c,handle);
 
     ssize = rsize = blockPtr->width;
@@ -1507,9 +1561,9 @@ color(red, green, blue, mapa)
     unsigned char mapa[MAXCOLORMAPSIZE][3];
 {
     int x;
-    for (x=(alphaOffset != 0);x<=MAXCOLORMAPSIZE;x++) {
-	if ((mapa[x][CM_RED]==red) && (mapa[x][CM_GREEN]==green) &&
-		(mapa[x][CM_BLUE]==blue)) {
+    for (x=(alphaOffset != 0) ; x<=MAXCOLORMAPSIZE ; x++) {
+	if ((mapa[x][CM_RED] == red) && (mapa[x][CM_GREEN] == green) &&
+		(mapa[x][CM_BLUE] == blue)) {
 	    return x;
 	}
     }
@@ -1522,10 +1576,10 @@ nuevo(red, green, blue, mapa)
     int red,green,blue;
     unsigned char mapa[MAXCOLORMAPSIZE][3];
 {
-    int x;
-    for (x=(alphaOffset != 0);x<=num;x++) {
-	if ((mapa[x][CM_RED]==red) && (mapa[x][CM_GREEN]==green) &&
-		(mapa[x][CM_BLUE]==blue)) {
+    int x = (alphaOffset != 0);
+    for (; x<=num ; x++) {
+	if ((mapa[x][CM_RED] == red) && (mapa[x][CM_GREEN] == green) &&
+		(mapa[x][CM_BLUE] == blue)) {
 	    return 0;
 	}
     }
@@ -1537,9 +1591,9 @@ savemap(blockPtr,mapa)
     Tk_PhotoImageBlock *blockPtr;
     unsigned char mapa[MAXCOLORMAPSIZE][3];
 {
-    unsigned char  *colores;
+    unsigned char *colores;
     int x,y;
-    unsigned char  red,green,blue;
+    unsigned char red,green,blue;
 
     if (alphaOffset) {
 	num = 0;
@@ -1550,22 +1604,22 @@ savemap(blockPtr,mapa)
 	num = -1;
     }
 
-    for(y=0;y<blockPtr->height;y++) {
-	colores=blockPtr->pixelPtr + blockPtr->offset[0]
+    for(y=0 ; y<blockPtr->height ; y++) {
+	colores = blockPtr->pixelPtr + blockPtr->offset[0]
 		+ y * blockPtr->pitch;
-	for(x=0;x<blockPtr->width;x++) {
+	for(x=0 ; x<blockPtr->width ; x++) {
 	    if (!alphaOffset || (colores[alphaOffset] != 0)) {
 		red = colores[0];
 		green = colores[greenOffset];
 		blue = colores[blueOffset];
 		if (nuevo(red,green,blue,mapa)) {
 		    num++;
-		    if (num>=MAXCOLORMAPSIZE) {
+		    if (num >= MAXCOLORMAPSIZE) {
 			return;
 		    }
-		    mapa[num][CM_RED]=red;
-		    mapa[num][CM_GREEN]=green;
-		    mapa[num][CM_BLUE]=blue;
+		    mapa[num][CM_RED] = red;
+		    mapa[num][CM_GREEN] = green;
+		    mapa[num][CM_BLUE] = blue;
 		}
 	    }
 	    colores += pixelSize;
@@ -1582,10 +1636,10 @@ ReadValue()
     if (csize == 0) {
 	return EOF;
     }
-    if (alphaOffset && (pixelo[alphaOffset]==0)) {
+    if (alphaOffset && (pixelo[alphaOffset] == 0)) {
 	col = 0;
     } else {
-	col = color(pixelo[0],pixelo[greenOffset],pixelo[blueOffset], mapa);
+	col = color(pixelo[0], pixelo[greenOffset], pixelo[blueOffset], mapa);
     }
     pixelo += pixelSize;
     if (--ssize <= 0) {
@@ -1599,48 +1653,53 @@ ReadValue()
 
 
 
-/*-----------------------------------------------------------------------
+/*
+ *-----------------------------------------------------------------------
  *
  * miGIF Compression - mouse and ivo's GIF-compatible compression
  *
- *          -run length encoding compression routines-
+ *		-run length encoding compression routines-
  *
  * Copyright (C) 1998 Hutchison Avenue Software Corporation
- *               http://www.hasc.com
- *               info@hasc.com
- *
- * Permission to use, copy, modify, and distribute this software and its
- * documentation for any purpose and without fee is hereby granted, provided
- * that the above copyright notice appear in all copies and that both that
- * copyright notice and this permission notice appear in supporting
- * documentation.  This software is provided "AS IS." The Hutchison Avenue 
- * Software Corporation disclaims all warranties, either express or implied, 
- * including but not limited to implied warranties of merchantability and 
- * fitness for a particular purpose, with respect to this code and accompanying
- * documentation. 
+ *		 http://www.hasc.com
+ *		 info@hasc.com
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose and without fee is hereby
+ * granted, provided that the above copyright notice appear in all
+ * copies and that both that copyright notice and this permission
+ * notice appear in supporting documentation.  This software is
+ * provided "AS IS." The Hutchison Avenue Software Corporation
+ * disclaims all warranties, either express or implied, including but
+ * not limited to implied warranties of merchantability and fitness
+ * for a particular purpose, with respect to this code and
+ * accompanying documentation.
  * 
- * The miGIF compression routines do not, strictly speaking, generate files 
- * conforming to the GIF spec, since the image data is not LZW-compressed 
- * (this is the point: in order to avoid transgression of the Unisys patent 
- * on the LZW algorithm.)  However, miGIF generates data streams that any 
- * reasonably sane LZW decompresser will decompress to what we want.
- *
- * miGIF compression uses run length encoding. It compresses horizontal runs 
- * of pixels of the same color. This type of compression gives good results
- * on images with many runs, for example images with lines, text and solid 
- * shapes on a solid-colored background. It gives little or no compression 
- * on images with few runs, for example digital or scanned photos.
- *
- *                               der Mouse
- *                      mouse@rodents.montreal.qc.ca
- *            7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B
- *
- *                             ivo@hasc.com
+ * The miGIF compression routines do not, strictly speaking, generate
+ * files conforming to the GIF spec, since the image data is not
+ * LZW-compressed (this is the point: in order to avoid transgression
+ * of the Unisys patent on the LZW algorithm.)  However, miGIF
+ * generates data streams that any reasonably sane LZW decompresser
+ * will decompress to what we want.
+ *
+ * miGIF compression uses run length encoding. It compresses
+ * horizontal runs of pixels of the same color. This type of
+ * compression gives good results on images with many runs, for
+ * example images with lines, text and solid shapes on a solid-colored
+ * background. It gives little or no compression on images with few
+ * runs, for example digital or scanned photos.
+ *
+ *				 der Mouse
+ *			mouse@rodents.montreal.qc.ca
+ *	      7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B
+ *
+ *			       ivo@hasc.com
  *
  * The Graphics Interchange Format(c) is the Copyright property of
  * CompuServe Incorporated.  GIF(sm) is a Service Mark property of
  * CompuServe Incorporated.
  *
+ *-----------------------------------------------------------------------
  */
 
 static int rl_pixel;
@@ -1665,145 +1724,172 @@ static Tcl_Channel ofile;
 static unsigned char oblock[256];
 static int oblen;
 
-/* Used only when debugging GIF compression code */
-/* #define DEBUGGING_ENVARS */
+/*
+ * Used only when debugging GIF compression code
+ */
+/* #define MIGIF_DEBUGGING_ENVARS */
 
-#ifdef DEBUGGING_ENVARS
+#ifdef MIGIF_DEBUGGING_ENVARS
 
 static int verbose_set = 0;
 static int verbose;
-#define VERBOSE (verbose_set?verbose:set_verbose())
+#define MIGIF_VERBOSE (verbose_set?verbose:set_verbose())
+#define DEBUGMSG(printf_args) if (MIGIF_VERBOSE) { printf printf_args; }
 
-static int set_verbose(void)
+static int
+set_verbose(void)
 {
- verbose = !!getenv("GIF_VERBOSE");
- verbose_set = 1;
- return(verbose);
+    verbose = !!getenv("MIGIF_VERBOSE");
+    verbose_set = 1;
+    return verbose;
 }
 
-#else
-
-#define VERBOSE 0
-
-#endif
-
-
 static CONST char *
 binformat(v, nbits)
     unsigned int v;
     int nbits;
 {
- static char bufs[8][64];
- static int bhand = 0;
- unsigned int bit;
- int bno;
- char *bp;
-
- bhand --;
- if (bhand < 0) bhand = (sizeof(bufs)/sizeof(bufs[0]))-1;
- bp = &bufs[bhand][0];
- for (bno=nbits-1,bit=((unsigned int)1)<<bno;bno>=0;bno--,bit>>=1)
-  { *bp++ = (v & bit) ? '1' : '0';
-    if (((bno&3) == 0) && (bno != 0)) *bp++ = '.';
-  }
- *bp = '\0';
- return(&bufs[bhand][0]);
+    static char bufs[8][64];
+    static int bhand = 0;
+    unsigned int bit;
+    int bno;
+    char *bp;
+
+    bhand--;
+    if (bhand < 0) {
+	bhand = (sizeof(bufs) / sizeof(bufs[0])) - 1;
+    }
+    bp = &bufs[bhand][0];
+    for (bno=nbits-1,bit=((unsigned int)1)<<bno ; bno>=0 ; bno--,bit>>=1) {
+	*bp++ = (v & bit) ? '1' : '0';
+	if (((bno&3) == 0) && (bno != 0)) {
+	    *bp++ = '.';
+	}
+    }
+    *bp = '\0';
+    return &bufs[bhand][0];
 }
 
-static void write_block()
+#else
+
+#define MIGIF_VERBOSE 0
+#define DEBUGMSG(printf_args) /* do nothing */
+
+#endif
+
+static void
+write_block()
 {
- int i;
- unsigned char c;
-
- if (VERBOSE)
-  { printf("write_block %d:",oblen);
-    for (i=0;i<oblen;i++) printf(" %02x",oblock[i]);
-    printf("\n");
-  }
- c = oblen;
- Tcl_Write(ofile, (char *) &c, 1);
- Tcl_Write(ofile, (char *) &oblock[0], oblen);
- oblen = 0;
+    int i;
+    unsigned char c;
+
+    if (MIGIF_VERBOSE) {
+	printf("write_block %d:", oblen);
+	for (i=0 ; i<oblen ; i++) {
+	    printf(" %02x", oblock[i]);
+	}
+	printf("\n");
+    }
+    c = oblen;
+    Tcl_Write(ofile, (char *) &c, 1);
+    Tcl_Write(ofile, (char *) &oblock[0], oblen);
+    oblen = 0;
 }
 
 static void
 block_out(c)
     unsigned char c;
 {
- if (VERBOSE) printf("block_out %s\n",binformat(c,8));
- oblock[oblen++] = c;
- if (oblen >= 255) write_block();
+    DEBUGMSG(("block_out %s\n", binformat(c, 8)));
+    oblock[oblen++] = c;
+    if (oblen >= 255) {
+	write_block();
+    }
 }
 
-static void block_flush()
+static void
+block_flush()
 {
- if (VERBOSE) printf("block_flush\n");
- if (oblen > 0) write_block();
+    DEBUGMSG(("block_flush\n"));
+    if (oblen > 0) {
+	write_block();
+    }
 }
 
-static void output(val)
+static void
+output(val)
     int val;
 {
- if (VERBOSE) printf("output %s [%s %d %d]\n",binformat(val,out_bits),binformat(obuf,obits),obits,out_bits);
- obuf |= val << obits;
- obits += out_bits;
- while (obits >= 8)
-  { block_out(obuf&0xff);
-    obuf >>= 8;
-    obits -= 8;
-  }
- if (VERBOSE) printf("output leaving [%s %d]\n",binformat(obuf,obits),obits);
+    DEBUGMSG(("output %s [%s %d %d]\n", binformat(val, out_bits),
+	    binformat(obuf, obits), obits, out_bits));
+    obuf |= val << obits;
+    obits += out_bits;
+    while (obits >= 8) {
+	block_out(obuf&0xff);
+	obuf >>= 8;
+	obits -= 8;
+    }
+    DEBUGMSG(("output leaving [%s %d]\n", binformat(obuf, obits), obits));
 }
 
-static void output_flush()
+static void
+output_flush()
 {
- if (VERBOSE) printf("output_flush\n");
- if (obits > 0) block_out(obuf);
- block_flush();
+    DEBUGMSG(("output_flush\n"));
+    if (obits > 0) {
+	block_out(obuf);
+    }
+    block_flush();
 }
 
-static void did_clear()
+static void
+did_clear()
 {
- if (VERBOSE) printf("did_clear\n");
- out_bits = out_bits_init;
- out_bump = out_bump_init;
- out_clear = out_clear_init;
- out_count = 0;
- rl_table_max = 0;
- just_cleared = 1;
+    DEBUGMSG(("did_clear\n"));
+    out_bits = out_bits_init;
+    out_bump = out_bump_init;
+    out_clear = out_clear_init;
+    out_count = 0;
+    rl_table_max = 0;
+    just_cleared = 1;
 }
 
 static void
 output_plain(c)
     int c;
 {
- if (VERBOSE) printf("output_plain %s\n",binformat(c,out_bits));
- just_cleared = 0;
- output(c);
- out_count ++;
- if (out_count >= out_bump)
-  { out_bits ++;
-    out_bump += 1 << (out_bits - 1);
-  }
- if (out_count >= out_clear)
-  { output(code_clear);
-    did_clear();
-  }
+    DEBUGMSG(("output_plain %s\n", binformat(c, out_bits)));
+    just_cleared = 0;
+    output(c);
+    out_count++;
+    if (out_count >= out_bump) {
+	out_bits++;
+	out_bump += 1 << (out_bits - 1);
+    }
+    if (out_count >= out_clear) {
+	output(code_clear);
+	did_clear();
+    }
 }
 
-static unsigned int isqrt(x)
+static unsigned int
+isqrt(x)
     unsigned int x;
 {
- unsigned int r;
- unsigned int v;
-
- if (x < 2) return(x);
- for (v=x,r=1;v;v>>=2,r<<=1) ;
- while (1)
-  { v = ((x / r) + r) / 2;
-    if ((v == r) || (v == r+1)) return(r);
-    r = v;
-  }
+    unsigned int r;
+    unsigned int v;
+
+    if (x < 2) {
+	return x;
+    }
+    for (v=x,r=1 ; v ; v>>=2,r<<=1);
+    while (1) {
+	v = ((x / r) + r) / 2;
+	if (v==r || v==r+1) {
+	    return r;
+	}
+	r = v;
+    }
 }
 
 static unsigned int
@@ -1811,205 +1897,224 @@ compute_triangle_count(count, nrepcodes)
     unsigned int count;
     unsigned int nrepcodes;
 {
- unsigned int perrep;
- unsigned int cost;
-
- cost = 0;
- perrep = (nrepcodes * (nrepcodes+1)) / 2;
- while (count >= perrep)
-  { cost += nrepcodes;
-    count -= perrep;
-  }
- if (count > 0)
-  { unsigned int n;
-    n = isqrt(count);
-    while ((n*(n+1)) >= 2*count) n --;
-    while ((n*(n+1)) < 2*count) n ++;
-    cost += n;
-  }
- return(cost);
+    unsigned int perrep;
+    unsigned int cost;
+
+    cost = 0;
+    perrep = (nrepcodes * (nrepcodes+1)) / 2;
+    while (count >= perrep) {
+	cost += nrepcodes;
+	count -= perrep;
+    }
+    if (count > 0) {
+	unsigned int n;
+	n = isqrt(count);
+	while (n*(n+1) >= 2*count) {
+	    n--;
+	}
+	while (n*(n+1) < 2*count) {
+	    n++;
+	}
+	cost += n;
+    }
+    return cost;
 }
 
-static void max_out_clear()
+static void
+max_out_clear()
 {
- out_clear = max_ocodes;
+    out_clear = max_ocodes;
 }
 
-static void reset_out_clear()
+static void
+reset_out_clear()
 {
- out_clear = out_clear_init;
- if (out_count >= out_clear)
-  { output(code_clear);
-    did_clear();
-  }
+    out_clear = out_clear_init;
+    if (out_count >= out_clear) {
+	output(code_clear);
+	did_clear();
+    }
 }
 
 static void
 rl_flush_fromclear(count)
     int count;
 {
- int n;
-
- if (VERBOSE) printf("rl_flush_fromclear %d\n",count);
- max_out_clear();
- rl_table_pixel = rl_pixel;
- n = 1;
- while (count > 0)
-  { if (n == 1)
-     { rl_table_max = 1;
-       output_plain(rl_pixel);
-       count --;
-     }
-    else if (count >= n)
-     { rl_table_max = n;
-       output_plain(rl_basecode+n-2);
-       count -= n;
-     }
-    else if (count == 1)
-     { rl_table_max ++;
-       output_plain(rl_pixel);
-       count = 0;
-     }
-    else
-     { rl_table_max ++;
-       output_plain(rl_basecode+count-2);
-       count = 0;
-     }
-    if (out_count == 0) n = 1; else n ++;
-  }
- reset_out_clear();
- if (VERBOSE) printf("rl_flush_fromclear leaving table_max=%d\n",rl_table_max);
+    int n;
+
+    DEBUGMSG(("rl_flush_fromclear %d\n", count));
+    max_out_clear();
+    rl_table_pixel = rl_pixel;
+    n = 1;
+    while (count > 0) {
+	if (n == 1) {
+	    rl_table_max = 1;
+	    output_plain(rl_pixel);
+	    count--;
+	} else if (count >= n) {
+	    rl_table_max = n;
+	    output_plain(rl_basecode+n-2);
+	    count -= n;
+	} else if (count == 1) {
+	    rl_table_max++;
+	    output_plain(rl_pixel);
+	    count = 0;
+	} else {
+	    rl_table_max++;
+	    output_plain(rl_basecode+count-2);
+	    count = 0;
+	}
+	if (out_count == 0) {
+	    n = 1;
+	} else {
+	    n++;
+	}
+    }
+    reset_out_clear();
+    DEBUGMSG(("rl_flush_fromclear leaving table_max=%d\n", rl_table_max));
 }
 
-static void rl_flush_clearorrep(count)
+static void
+rl_flush_clearorrep(count)
     int count;
 {
- int withclr;
-
- if (VERBOSE) printf("rl_flush_clearorrep %d\n",count);
- withclr = 1 + compute_triangle_count(count,max_ocodes);
- if (withclr < count)
-  { output(code_clear);
-    did_clear();
-    rl_flush_fromclear(count);
-  }
- else
-  { for (;count>0;count--) output_plain(rl_pixel);
-  }
+    int withclr;
+
+    DEBUGMSG(("rl_flush_clearorrep %d\n", count));
+    withclr = 1 + compute_triangle_count(count, max_ocodes);
+    if (withclr < count) {
+	output(code_clear);
+	did_clear();
+	rl_flush_fromclear(count);
+    } else {
+	for (; count>0 ; count--) {
+	    output_plain(rl_pixel);
+	}
+    }
 }
 
-static void rl_flush_withtable(count)
+static void
+rl_flush_withtable(count)
     int count;
 {
- int repmax;
- int repleft;
- int leftover;
-
- if (VERBOSE) printf("rl_flush_withtable %d\n",count);
- repmax = count / rl_table_max;
- leftover = count % rl_table_max;
- repleft = (leftover ? 1 : 0);
- if (out_count+repmax+repleft > max_ocodes)
-  { repmax = max_ocodes - out_count;
-    leftover = count - (repmax * rl_table_max);
-    repleft = 1 + compute_triangle_count(leftover,max_ocodes);
-  }
- if (VERBOSE) printf("rl_flush_withtable repmax=%d leftover=%d repleft=%d\n",repmax,leftover,repleft);
- if (1+(int)compute_triangle_count(count,max_ocodes) < repmax+repleft)
-  { output(code_clear);
-    did_clear();
-    rl_flush_fromclear(count);
-    return;
-  }
- max_out_clear();
- for (;repmax>0;repmax--) output_plain(rl_basecode+rl_table_max-2);
- if (leftover)
-  { if (just_cleared)
-     { rl_flush_fromclear(leftover);
-     }
-    else if (leftover == 1)
-     { output_plain(rl_pixel);
-     }
-    else
-     { output_plain(rl_basecode+leftover-2);
-     }
-  }
- reset_out_clear();
+    int repmax;
+    int repleft;
+    int leftover;
+
+    DEBUGMSG(("rl_flush_withtable %d\n", count));
+    repmax = count / rl_table_max;
+    leftover = count % rl_table_max;
+    repleft = (leftover ? 1 : 0);
+    if (out_count+repmax+repleft > max_ocodes) {
+	repmax = max_ocodes - out_count;
+	leftover = count - (repmax * rl_table_max);
+	repleft = 1 + compute_triangle_count(leftover, max_ocodes);
+    }
+    DEBUGMSG(("rl_flush_withtable repmax=%d leftover=%d repleft=%d\n",
+	    repmax, leftover, repleft));
+    if (1+(int)compute_triangle_count(count, max_ocodes) < repmax+repleft) {
+	output(code_clear);
+	did_clear();
+	rl_flush_fromclear(count);
+	return;
+    }
+    max_out_clear();
+    for (; repmax>0 ; repmax--) {
+	output_plain(rl_basecode + rl_table_max - 2);
+    }
+    if (leftover) {
+	if (just_cleared) {
+	    rl_flush_fromclear(leftover);
+	} else if (leftover == 1) {
+	    output_plain(rl_pixel);
+	} else {
+	    output_plain(rl_basecode + leftover - 2);
+	}
+    }
+    reset_out_clear();
 }
 
-static void rl_flush()
+static void
+rl_flush()
 {
- if (VERBOSE) printf("rl_flush [ %d %d\n",rl_count,rl_pixel);
- if (rl_count == 1)
-  { output_plain(rl_pixel);
+    DEBUGMSG(("rl_flush [ %d %d\n", rl_count, rl_pixel));
+    if (rl_count == 1) {
+	output_plain(rl_pixel);
+	rl_count = 0;
+	DEBUGMSG(("rl_flush ]\n"));
+	return;
+    }
+    if (just_cleared) {
+	rl_flush_fromclear(rl_count);
+    } else if ((rl_table_max < 2) || (rl_table_pixel != rl_pixel)) {
+	rl_flush_clearorrep(rl_count);
+    } else {
+	rl_flush_withtable(rl_count);
+    }
+    DEBUGMSG(("rl_flush ]\n"));
     rl_count = 0;
-    if (VERBOSE) printf("rl_flush ]\n");
-    return;
-  }
- if (just_cleared)
-  { rl_flush_fromclear(rl_count);
-  }
- else if ((rl_table_max < 2) || (rl_table_pixel != rl_pixel))
-  { rl_flush_clearorrep(rl_count);
-  }
- else
-  { rl_flush_withtable(rl_count);
-  }
- if (VERBOSE) printf("rl_flush ]\n");
- rl_count = 0;
 }
 
 
-static void compress( init_bits, handle, readValue )
+static void
+compress(init_bits, handle, readValue)
     int init_bits;
     Tcl_Channel handle;
     ifunptr readValue;
 {
- int c;
-
- ofile = handle;
- obuf = 0;
- obits = 0;
- oblen = 0;
- code_clear = 1 << (init_bits - 1);
- code_eof = code_clear + 1;
- rl_basecode = code_eof + 1;
- out_bump_init = (1 << (init_bits - 1)) - 1;
- /* for images with a lot of runs, making out_clear_init larger will
-    give better compression. */ 
- out_clear_init = (init_bits <= 3) ? 9 : (out_bump_init-1);
-#ifdef DEBUGGING_ENVARS
-  { const char *ocienv;
-    ocienv = getenv("GIF_OUT_CLEAR_INIT");
-    if (ocienv)
-     { out_clear_init = atoi(ocienv);
-       if (VERBOSE) printf("[overriding out_clear_init to %d]\n",out_clear_init);
-     }
-  }
+    int c;
+
+    ofile = handle;
+    obuf = 0;
+    obits = 0;
+    oblen = 0;
+    code_clear = 1 << (init_bits - 1);
+    code_eof = code_clear + 1;
+    rl_basecode = code_eof + 1;
+    out_bump_init = (1 << (init_bits - 1)) - 1;
+    /*
+     * For images with a lot of runs, making out_clear_init larger
+     * will give better compression.
+     */
+    out_clear_init = (init_bits <= 3) ? 9 : (out_bump_init-1);
+#ifdef MIGIF_DEBUGGING_ENVARS
+    {
+	const char *ocienv;
+	ocienv = getenv("MIGIF_OUT_CLEAR_INIT");
+	if (ocienv) {
+	    out_clear_init = atoi(ocienv);
+	    DEBUGMSG(("[overriding out_clear_init to %d]\n", out_clear_init));
+	}
+    }
 #endif
- out_bits_init = init_bits;
- max_ocodes = (1 << GIFBITS) - ((1 << (out_bits_init - 1)) + 3);
- did_clear();
- output(code_clear);
- rl_count = 0;
- while (1)
-  { c = readValue();
-    if ((rl_count > 0) && (c != rl_pixel)) rl_flush();
-    if (c == EOF) break;
-    if (rl_pixel == c)
-     { rl_count ++;
-     }
-    else
-     { rl_pixel = c;
-       rl_count = 1;
-     }
-  }
- output(code_eof);
- output_flush();
+    out_bits_init = init_bits;
+    max_ocodes = (1 << GIFBITS) - ((1 << (out_bits_init - 1)) + 3);
+    did_clear();
+    output(code_clear);
+    rl_count = 0;
+    while (1) {
+	c = readValue();
+	if ((rl_count > 0) && (c != rl_pixel)) {
+	    rl_flush();
+	}
+	if (c == EOF) {
+	    break;
+	}
+	if (rl_pixel == c) {
+	    rl_count++;
+	} else {
+	    rl_pixel = c;
+	    rl_count = 1;
+	}
+    }
+    output(code_eof);
+    output_flush();
 }
 
-/*-----------------------------------------------------------------------
+/*
+ *-----------------------------------------------------------------------
  *
  * End of miGIF section  - See copyright notice at start of section.
  *
- *-----------------------------------------------------------------------*/
+ *-----------------------------------------------------------------------
+ */