Simplify and fix reading of ASCII images.

2006-09-06  Matthias Clasen  <mclasen@redhat.com>

	* io-pnm.c: Simplify and fix reading of ASCII images.

2 files changed, 71 insertions, 82 deletions

diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index 58029e44fe..b72ed39b2f 100644
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,7 @@
+2006-09-06  Matthias Clasen  <mclasen@redhat.com>
+
+	* io-pnm.c: Simplify and fix reading of ASCII images. 
+
 2006-08-17  Matthias Clasen  <mclasen@redhat.com>
 
 	* === Released 2.10.2 ===
diff --git a/gdk-pixbuf/io-pnm.c b/gdk-pixbuf/io-pnm.c
index 3af9794c25..af40f0fe25 100644
--- a/gdk-pixbuf/io-pnm.c
+++ b/gdk-pixbuf/io-pnm.c
@@ -527,109 +527,90 @@ pnm_read_raw_scanline (PnmLoaderContext *context)
 }
 
 static gint
-pnm_read_ascii_scanline (PnmLoaderContext *context)
+pnm_read_ascii_mono_scanline (PnmLoaderContext *context)
 {
 	PnmIOBuffer *inbuf;
-	guint offset;
-	guint value, numval, i;
-	guchar data;
-	guchar mask;
-	guchar *dptr;
+	guint value;
 	gint retval;
+	guchar *dptr;
 	gint max_length;
-	
-	g_return_val_if_fail (context != NULL, PNM_FATAL_ERR);
-	
-	data = mask = 0;
-	
-	inbuf = &context->inbuf;
-	
-	context->dptr = context->pixels + context->output_row * context->rowstride;
-	
-	switch (context->type) {
-	case PNM_FORMAT_PBM:
+
+	if (context->type == PNM_TYPE_PBM)
 		max_length = 1;
-		numval = MIN (8, context->width - context->output_col);
-		offset = context->output_col / 8;
-		break;
-	case PNM_FORMAT_PGM:
-		max_length = -1;
-		numval = 1;
-		offset = context->output_col;
-		break;
-	case PNM_FORMAT_PPM:
+	else
 		max_length = -1;
-		numval = 3;
-		offset = context->output_col * 3;
-		break;
-		
-	default:
-		g_set_error (context->error,
-			     GDK_PIXBUF_ERROR,
-			     GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
-			     _("PNM image format is invalid"));
 
-		return PNM_FATAL_ERR;
+	inbuf = &context->inbuf;
+
+	context->dptr = context->pixels + context->output_row * context->rowstride;
+
+	dptr = context->dptr + context->output_col * 3;
+
+	while (TRUE) {
+		retval = pnm_read_next_value (inbuf, max_length, &value, context->error);
+		if (retval != PNM_OK)
+			return retval;
+
+		if (context->type == PNM_TYPE_PBM) {
+			value = value ? 0 : 0xff;
+		}
+		else {
+			/* scale the color up or down to an 8-bit color depth */
+			if (value > context->maxval)
+				value = 255;
+			else
+				value = (guchar)(255 * value / context->maxval);
+		}
+			
+		*dptr++ = value;
+		*dptr++ = value;
+		*dptr++ = value;
+
+		context->output_col++;
+
+		if (context->output_col == context->width) {
+			context->output_col = 0;
+			context->output_row++;
+			break;
+		}
 	}
+
+	return PNM_OK;
+}
+
+static gint
+pnm_read_ascii_color_scanline (PnmLoaderContext *context)
+{
+	PnmIOBuffer *inbuf;
+	guint value, i;
+	guchar *dptr;
+	gint retval;
+	
+	inbuf = &context->inbuf;
+	
+	context->dptr = context->pixels + context->output_row * context->rowstride;
 	
-	dptr = context->dptr + offset + context->scan_state;
+	dptr = context->dptr + context->output_col * 3 + context->scan_state;
 	
 	while (TRUE) {
-		if (context->type == PNM_FORMAT_PBM) {
-			mask = 0x80;
-			data = 0;
-			numval = MIN (8, context->width - context->output_col);
-		}
-		
-		for (i = context->scan_state; i < numval; i++) {
-			retval = pnm_read_next_value (inbuf, max_length, 
-						      &value, context->error);
+		for (i = context->scan_state; i < 3; i++) {
+			retval = pnm_read_next_value (inbuf, -1, &value, context->error);
 			if (retval != PNM_OK) {
 				/* save state and return */
 				context->scan_state = i;
 				return retval;
 			}
 			
-			switch (context->type) {
-			case PNM_FORMAT_PBM:
-				if (value)
-					data |= mask;
-				mask >>= 1;
-				
-				break;
-			case PNM_FORMAT_PGM:
-			case PNM_FORMAT_PPM:
-				/* scale the color up or down to an 8-bit color depth */
-				if (value > context->maxval)
-					*dptr++ = 255;
-				else
-					*dptr++ = (guchar)(255 * value / context->maxval);
-				break;
-			default:
-				g_set_error (context->error,
-					     GDK_PIXBUF_ERROR,
-					     GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
-					     _("PNM image format is invalid"));
-				return PNM_FATAL_ERR;
-				break;
-			}
+			if (value > context->maxval)
+				*dptr++ = 255;
+			else
+				*dptr++ = (guchar)(255 * value / context->maxval);
 		}
 		
 		context->scan_state = 0;
-		
-		if (context->type == PNM_FORMAT_PBM) {
-			*dptr++ = data;
-			context->output_col += numval;
-		} else {
-			context->output_col++;
-		}
+		context->output_col++;
 		
 		if (context->output_col == context->width) {
-			if (context->type == PNM_FORMAT_PBM)
-				explode_bitmap_into_buf (context);
-			else if (context->type == PNM_FORMAT_PGM)
-				explode_gray_into_buf (context);
-			
 			context->output_col = 0;
 			context->output_row++;
 			break;
@@ -659,8 +640,12 @@ pnm_read_scanline (PnmLoaderContext *context)
 		break;
 	case PNM_FORMAT_PBM:
 	case PNM_FORMAT_PGM:
+		retval = pnm_read_ascii_mono_scanline (context);
+		if (retval != PNM_OK)
+			return retval;
+		break;		
 	case PNM_FORMAT_PPM:
-		retval = pnm_read_ascii_scanline (context);
+		retval = pnm_read_ascii_color_scanline (context);
 		if (retval != PNM_OK)
 			return retval;
 		break;