better handling of jpeg warnings

libvips/conversion/tilecache.c

@@ -398,6 +398,8 @@ vips_tile_destroy( VipsTile *tile )
 static void
 vips_block_cache_init( VipsBlockCache *cache )
 {
+	printf( "vips_block_cache_init\n" ); 
+
 	cache->tile_width = 128;
 	cache->tile_height = 128;
 	cache->max_tiles = 1000;
@@ -652,10 +654,6 @@ vips_line_cache_build( VipsObject *object )
 	block_cache->tile_width = block_cache->in->Xsize;
 	block_cache->tile_height = 1;
 
-	/* This adjust with request size, see vips_line_cache_gen().
-	 */
-	block_cache->max_tiles = 100;
-
 	if( vips_image_pio_input( block_cache->in ) )
 		return( -1 );
 
@@ -692,6 +690,13 @@ vips_line_cache_class_init( VipsLineCacheClass *class )
 static void
 vips_line_cache_init( VipsLineCache *cache )
 {
+	printf( "vips_line_cache_init\n" ); 
+
+	/* This adjust with request size, see vips_line_cache_gen().
+	 */
+	((VipsBlockCache *) cache)->max_tiles = 500;
+
+	((VipsBlockCache *) cache)->strategy = VIPS_CACHE_SEQUENTIAL;
 }
 
 /**

libvips/foreign/jpeg2vips.c

@@ -167,7 +167,7 @@ readjpeg_free( ReadJpeg *jpeg )
 			vips_warn( "VipsJpeg", 
 				_( "read gave %ld warnings" ), 
 				jpeg->eman.pub.num_warnings );
-			vips_warn( "VipsJpeg", "%s", vips_error_buffer() );
+			vips_warn( NULL, "%s", vips_error_buffer() );
 		}
 
 		/* Make the message only appear once.

libvips/foreign/vips2jpeg.c

@@ -202,6 +202,7 @@ write_new( VipsImage *in )
         write->cinfo.err = jpeg_std_error( &write->eman.pub );
 	write->eman.pub.error_exit = vips__new_error_exit;
 	write->eman.pub.output_message = vips__new_output_message;
+	write->eman.pub.output_message = vips__new_output_message;
 	write->eman.fp = NULL;
 	write->profile_bytes = NULL;
 	write->profile_length = 0;

libvips/iofuncs/error.c

@@ -311,7 +311,8 @@ vips_vdiag( const char *domain, const char *fmt, va_list ap )
 	if( !g_getenv( IM_DIAGNOSTICS ) ) {
 		g_mutex_lock( vips__global_lock );
 		(void) fprintf( stderr, _( "%s: " ), _( "vips diagnostic" ) );
-		(void) fprintf( stderr, _( "%s: " ), domain );
+		if( domain )
+			(void) fprintf( stderr, _( "%s: " ), domain );
 		(void) vfprintf( stderr, fmt, ap );
 		(void) fprintf( stderr, "\n" );
 		g_mutex_unlock( vips__global_lock );
@@ -361,7 +362,8 @@ vips_vwarn( const char *domain, const char *fmt, va_list ap )
 	if( !g_getenv( IM_WARNING ) ) {
 		g_mutex_lock( vips__global_lock );
 		(void) fprintf( stderr, _( "%s: " ), _( "vips warning" ) );
-		(void) fprintf( stderr, _( "%s: " ), domain );
+		if( domain )
+			(void) fprintf( stderr, _( "%s: " ), domain );
 		(void) vfprintf( stderr, fmt, ap );
 		(void) fprintf( stderr, "\n" );
 		g_mutex_unlock( vips__global_lock );

tools/vips.c

@@ -1073,7 +1073,8 @@ main( int argc, char **argv )
 	 * since we don't want to use the vips7 compat wrappers in vips8
 	 * unless we have to. They don't support all args types.
 	 */
-	if( action && !handled && 
+	if( action && 
+		!handled && 
 		(fn = im_find_function( action )) ) {
 		(void) add_main_group( context, NULL );
 		parse_options( context, &argc, argv );
@@ -1087,11 +1088,17 @@ main( int argc, char **argv )
 
 		handled = TRUE;
 	}
-	im_error_clear();
+
+	/* im_find_function() set an error msg.
+	 */
+	if( action &&
+		!handled )
+		im_error_clear();
 
 	/* Could be a vips8 VipsOperation.
 	 */
-	if( action && !handled && 
+	if( action && 
+		!handled && 
 		(operation = vips_operation_new( action )) ) {
 		main_group = add_main_group( context, operation );
 		vips_call_options( main_group, operation );
@@ -1113,9 +1120,15 @@ main( int argc, char **argv )
 
 		handled = TRUE;
 	}
-	im_error_clear();
 
-	if( action && !handled ) {
+	/* vips_operation_new() set an error msg for unknown operation.
+	 */
+	if( action &&
+		!handled )
+		im_error_clear();
+
+	if( action && 
+		!handled ) {
 		printf( "%s", _( "possible actions:\n" ) );
 		for( i = 0; i < VIPS_NUMBER( actions ); i++ )
 			printf( "%10s - %s\n",