add a "const" to get_string

libvips/foreign/radiance.c

@@ -1056,7 +1056,7 @@ write_new( VipsImage *in, const char *filename )
 static int
 vips2rad_put_header( Write *write )
 {
-	char *str;
+	const char *str;
 	int i, j;
 	double d;
 

libvips/foreign/tiffsave.c

@@ -88,7 +88,7 @@ vips_foreign_save_tiff_build( VipsObject *object )
 	VipsForeignSave *save = (VipsForeignSave *) object;
 	VipsForeignSaveTiff *tiff = (VipsForeignSaveTiff *) object;
 
-	char *p;
+	const char *p;
 
 	if( VIPS_OBJECT_CLASS( vips_foreign_save_tiff_parent_class )->
 		build( object ) )

libvips/foreign/vips2jpeg.c

@@ -452,7 +452,7 @@ static int
 set_exif_resolution( ExifData *ed, VipsImage *im )
 {
 	double xres, yres;
-	char *p;
+	const char *p;
 	int unit;
 
 	VIPS_DEBUG_MSG( "set_exif_resolution: vips res of %g, %g\n",
@@ -578,7 +578,7 @@ static void
 vips_exif_update_entry( ExifEntry *entry, VipsExif *ve )
 {
 	char name[256];
-	char *value;
+	const char *value;
 
 	vips_snprintf( name, 256, "exif-ifd%d-%s", 
 		exif_entry_get_ifd( entry ),

libvips/include/vips/header.h

@@ -149,7 +149,7 @@ int vips_image_get_double( const VipsImage *image,
 	const char *field, double *out );
 void vips_image_set_double( VipsImage *image, const char *field, double d );
 int vips_image_get_string( const VipsImage *image, 
-	const char *field, char **out );
+	const char *field, const char **out );
 void vips_image_set_string( VipsImage *image, 
 	const char *field, const char *str );
 

libvips/iofuncs/header.c

@@ -1357,7 +1357,8 @@ vips_image_set_double( VipsImage *image, const char *field, double d )
  * Returns: 0 on success, -1 otherwise.
  */
 int
-vips_image_get_string( const VipsImage *image, const char *field, char **out )
+vips_image_get_string( const VipsImage *image, const char *field, 
+	const char **out )
 {
 	int i;
 	GValue value_copy = { 0 };

libvips/iofuncs/image.c

@@ -418,7 +418,7 @@ static void
 vips_image_summary( VipsObject *object, VipsBuf *buf )
 {
 	VipsImage *image = VIPS_IMAGE( object );
-	char *p;
+	const char *p;
 
 	vips_buf_appendf( buf, "%dx%d",
 		vips_image_get_width( image ), vips_image_get_height( image ) );

tools/vipsthumbnail.c

@@ -148,9 +148,7 @@ calculate_shrink( int width, int height, double *residual )
 static int
 thumbnail_find_jpegshrink( VipsImage *im )
 {
-	int shrink;
-
-	shrink = calculate_shrink( im->Xsize, im->Ysize, NULL );
+	int shrink = calculate_shrink( im->Xsize, im->Ysize, NULL );
 
 	if( shrink >= 8 )
 		return( 8 );