cvs: gd /libgd/src gd_tiff.c

nlopess		Sat Oct  6 10:52:09 2007 UTC

  Modified files:              
    /gd/libgd/src	gd_tiff.c 
  Log:
  replace pow(2, ) with a bitwise shift
  add comment to note that no overflow check is necessary in the colorMap* allocations
  
http://cvs.php.net/viewvc.cgi/gd/libgd/src/gd_tiff.c?r1=1.8&r2=1.9&diff_format=u
Index: gd/libgd/src/gd_tiff.c
diff -u gd/libgd/src/gd_tiff.c:1.8 gd/libgd/src/gd_tiff.c:1.9
--- gd/libgd/src/gd_tiff.c:1.8	Sat Oct  6 10:42:17 2007
+++ gd/libgd/src/gd_tiff.c	Sat Oct  6 10:52:09 2007
@@ -29,7 +29,7 @@
 
    ----------------------------------------------------------------------------
  */
-/* $Id: gd_tiff.c,v 1.8 2007/10/06 10:42:17 nlopess Exp $ */
+/* $Id: gd_tiff.c,v 1.9 2007/10/06 10:52:09 nlopess Exp $ */
 
 #ifdef HAVE_CONFIG_H
 	#include "config.h"
@@ -249,10 +249,10 @@
 
 	/* build the color map for 8 bit images */
 	if(bitDepth != 24) {
-		/*TODO: Add checking */
-		colorMapRed = (uint16 *) gdMalloc(3 * pow(2, bitsPerSample));
-		colorMapGreen = (uint16 *) gdMalloc(3 * pow(2, bitsPerSample));
-		colorMapBlue = (uint16 *) gdMalloc(3 * pow(2, bitsPerSample));
+		/* no overflow check is necessary because bitsPerSample is at most 8 and the following doesn't overflow */
+		colorMapRed = (uint16 *) gdMalloc(3 * (1 << bitsPerSample));
+		colorMapGreen = (uint16 *) gdMalloc(3 * (1 << bitsPerSample));
+		colorMapBlue = (uint16 *) gdMalloc(3 * (1 << bitsPerSample));
 
 		for(i = 0; i < image->colorsTotal; i++) {
 			colorMapRed[i] = gdImageRed(image,i) + (gdImageRed(image,i) * 256);
@@ -409,7 +409,7 @@
 	uint32 offset;
 
 	TIFFGetField(tiff, TIFFTAG_BITSPERSAMPLE, &bitsPerSample);
-	offset = pow(2, bitsPerSample);
+	offset = 1 << bitsPerSample;
 
 	if(color == 0) {
 		val = ctx.red[index];