Simplify expression and remove the possibility of div by 0

smalyshev · smalyshev · commit 57e7c3aac100 · 2019-07-07T16:16:05.000-07:00
Maybe should use exp2() but not sure about how supported it is.
diff --git a/ext/exif/exif.c b/ext/exif/exif.c
@@ -2683,7 +2683,7 @@ PHP_FUNCTION(exif_tagname)
 		RETURN_FALSE;
 	}
 
-	RETURN_STRING(szTemp)
+	RETURN_STRING(szTemp);
 }
 /* }}} */
 
@@ -3369,7 +3369,7 @@ static int exif_process_IFD_TAG(image_info_type *ImageInfo, char *dir_entry, cha
 				   have appropriate aperture information yet. */
 				if (ImageInfo->ApertureFNumber == 0) {
 					ImageInfo->ApertureFNumber
-						= (float)exp(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*log(2)*0.5);
+						= expf(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*logf(2.0)*0.5);
 				}
 				break;
 
@@ -3380,7 +3380,7 @@ static int exif_process_IFD_TAG(image_info_type *ImageInfo, char *dir_entry, cha
 				  */
 				if (ImageInfo->ExposureTime == 0) {
 					ImageInfo->ExposureTime
-						= (float)(1/exp(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*log(2)));
+						= expf(-exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*logf(2.0));
 				}
 				break;
 			case TAG_EXPOSURETIME:

Original file line number	Diff line number	Diff line change
`@@ -2683,7 +2683,7 @@ PHP_FUNCTION(exif_tagname)`
`2683`	`2683`	`RETURN_FALSE;`
`2684`	`2684`	`}`
`2685`	`2685`
`2686`		`- RETURN_STRING(szTemp)`
	`2686`	`+ RETURN_STRING(szTemp);`
`2687`	`2687`	`}`
`2688`	`2688`	`/* }}} */`
`2689`	`2689`
`@@ -3369,7 +3369,7 @@ static int exif_process_IFD_TAG(image_info_type ImageInfo, char dir_entry, cha`
`3369`	`3369`	`have appropriate aperture information yet. */`
`3370`	`3370`	`if (ImageInfo->ApertureFNumber == 0) {`
`3371`	`3371`	`ImageInfo->ApertureFNumber`
`3372`		`- = (float)exp(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)log(2)0.5);`
	`3372`	`+ = expf(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)logf(2.0)0.5);`
`3373`	`3373`	`}`
`3374`	`3374`	`break;`
`3375`	`3375`
`@@ -3380,7 +3380,7 @@ static int exif_process_IFD_TAG(image_info_type ImageInfo, char dir_entry, cha`
`3380`	`3380`	`*/`
`3381`	`3381`	`if (ImageInfo->ExposureTime == 0) {`
`3382`	`3382`	`ImageInfo->ExposureTime`
`3383`		`- = (float)(1/exp(exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*log(2)));`
	`3383`	`+ = expf(-exif_convert_any_format(value_ptr, format, ImageInfo->motorola_intel)*logf(2.0));`
`3384`	`3384`	`}`
`3385`	`3385`	`break;`
`3386`	`3386`	`case TAG_EXPOSURETIME:`