common parts of all lib*_read_data moved to io-main.h

[libucw.git] / images / io-libpng.c

diff --git a/images/io-libpng.c b/images/io-libpng.c
index dbf33d511dd359f97b32dda431782f3e244f0855..638427da8f3950647eb6b0a3558783dc732092f6 100644 (file)
--- a/images/io-libpng.c
+++ b/images/io-libpng.c
@@ -13,6 +13,7 @@
 #include "lib/mempool.h"
 #include "lib/fastbuf.h"
 #include "images/images.h"
+#include "images/io-main.h"
 #include <png.h>
 #include <setjmp.h>
 
@@ -143,29 +144,28 @@ libpng_read_header(struct image_io *io)
   switch (rd->color_type)
     {
       case PNG_COLOR_TYPE_GRAY:
-        io->flags |= COLOR_SPACE_GRAYSCALE;
+        io->flags = COLOR_SPACE_GRAYSCALE;
        io->number_of_colors = 1 << 8;
         break;
       case PNG_COLOR_TYPE_GRAY_ALPHA:
-        io->flags |= COLOR_SPACE_GRAYSCALE | IMAGE_ALPHA;
+        io->flags = COLOR_SPACE_GRAYSCALE | IMAGE_ALPHA;
        io->number_of_colors = 1 << 8;
         break;
       case PNG_COLOR_TYPE_RGB:
-        io->flags |= COLOR_SPACE_RGB;
+        io->flags = COLOR_SPACE_RGB;
        io->number_of_colors = 1 << 24;
         break;
       case PNG_COLOR_TYPE_RGB_ALPHA:
        io->number_of_colors = 1 << 24;
-        io->flags |= COLOR_SPACE_RGB | IMAGE_ALPHA;
+        io->flags = COLOR_SPACE_RGB | IMAGE_ALPHA;
         break;
       case PNG_COLOR_TYPE_PALETTE:
-        io->flags |= COLOR_SPACE_RGB | IMAGE_ALPHA;
+        io->flags = COLOR_SPACE_RGB | IMAGE_ALPHA | IMAGE_IO_HAS_PALETTE;
        int num_palette;
        if (png_get_PLTE(rd->png_ptr, rd->info_ptr, NULL, &num_palette))
          io->number_of_colors = num_palette;
        else
          io->number_of_colors = 1 << rd->bit_depth;
-       io->has_palette = 1;
         break;
       default:
         png_destroy_read_struct(&rd->png_ptr, &rd->info_ptr, &rd->end_ptr);
@@ -197,11 +197,9 @@ libpng_read_data(struct image_io *io)
         return 0;
     }
 
-  volatile int need_scale = io->cols != rd->cols || io->rows != rd->rows;
-  struct image * volatile img = need_scale ?
-    image_new(io->thread, rd->cols, rd->rows, io->flags & IMAGE_PIXEL_FORMAT, NULL) :
-    image_new(io->thread, rd->cols, rd->rows, io->flags, io->pool);
-  if (!img)
+  /* Prepare the image */
+  struct image_io_read_data_internals rdi;
+  if (unlikely(!image_io_read_data_prepare(&rdi, io, rd->cols, rd->rows)))
     {
       png_destroy_read_struct(&rd->png_ptr, &rd->info_ptr, &rd->end_ptr);
       return 0;
@@ -211,8 +209,7 @@ libpng_read_data(struct image_io *io)
     {
       DBG("Libpng failed to read the image, longjump saved us");
       png_destroy_read_struct(&rd->png_ptr, &rd->info_ptr, &rd->end_ptr);
-      if (need_scale || !io->pool)
-       image_destroy(img);
+      image_io_read_data_break(&rdi, io);
       return 0;
     }
 
@@ -265,6 +262,7 @@ libpng_read_data(struct image_io *io)
 
   /* Read image data */
   DBG("Reading image data");
+  struct image *img = rdi.image;
   byte *pixels = img->pixels;
   png_bytep rows[img->rows];
   for (uns r = 0; r < img->rows; r++, pixels += img->row_size)
@@ -275,29 +273,8 @@ libpng_read_data(struct image_io *io)
   /* Destroy libpng read structure */
   png_destroy_read_struct(&rd->png_ptr, &rd->info_ptr, &rd->end_ptr);
 
-  /* Scale and store the resulting image */
-  if (need_scale)
-    {
-      struct image *dest = image_new(io->thread, io->cols, io->rows, io->flags, io->pool);
-      if (!dest)
-        {
-         image_destroy(img);
-         return 0;
-       }
-      if (!image_scale(io->thread, dest, img))
-        {
-         image_destroy(img);
-         if (!io->pool)
-           image_destroy(dest);
-         return 0;
-       }
-      io->image = dest;
-    }
-  else
-    io->image = img;
-  io->image_destroy = !io->pool;
-
-  return 1;
+  /* Finish the image  */
+  return image_io_read_data_finish(&rdi, io);
 }
 
 int