1 files changed, 39 insertions, 22 deletions

diff --git a/src/image.c b/src/image.c
index 3dac7086cb4..c1c1671899b 100644
--- a/src/image.c
+++ b/src/image.c
@@ -2574,7 +2574,7 @@ xbm_image_p (Lisp_Object object)
 static int
 xbm_scan (char **s, char *end, char *sval, int *ival)
 {
-  unsigned char c;
+  unsigned char c UNINIT;
 
  loop:
 
@@ -5277,6 +5277,25 @@ pbm_scan_number (char **s, char *end)
   return val;
 }
 
+/* Scan an index from *S and return it.  It is a one-byte unsigned
+   index if !TWO_BYTE, and a two-byte big-endian unsigned index if
+   TWO_BYTE.  */
+
+static int
+pbm_scan_index (char **s, bool two_byte)
+{
+  char *p = *s;
+  unsigned char c0 = *p++;
+  int n = c0;
+  if (two_byte)
+    {
+      unsigned char c1 = *p++;
+      n = (n << 8) + c1;
+    }
+  *s = p;
+  return n;
+}
+
 
 /* Load PBM image IMG for use on frame F.  */
 
@@ -5499,7 +5518,8 @@ pbm_load (struct frame *f, struct image *img)
   else
     {
       int expected_size = height * width;
-      if (max_color_idx > 255)
+      bool two_byte = 255 < max_color_idx;
+      if (two_byte)
 	expected_size *= 2;
       if (type == PBM_COLOR)
 	expected_size *= 3;
@@ -5522,24 +5542,14 @@ pbm_load (struct frame *f, struct image *img)
 	    int r, g, b;
 
 	    if (type == PBM_GRAY && raw_p)
-	      {
-		r = g = b = *p++;
-		if (max_color_idx > 255)
-		  r = g = b = r * 256 + *p++;
-	      }
+	      r = g = b = pbm_scan_index (&p, two_byte);
 	    else if (type == PBM_GRAY)
 	      r = g = b = pbm_scan_number (&p, end);
 	    else if (raw_p)
 	      {
-		r = *p++;
-		if (max_color_idx > 255)
-		  r = r * 256 + *p++;
-		g = *p++;
-		if (max_color_idx > 255)
-		  g = g * 256 + *p++;
-		b = *p++;
-		if (max_color_idx > 255)
-		  b = b * 256 + *p++;
+		r = pbm_scan_index (&p, two_byte);
+		g = pbm_scan_index (&p, two_byte);
+		b = pbm_scan_index (&p, two_byte);
 	      }
 	    else
 	      {
@@ -7839,7 +7849,7 @@ gif_load (struct frame *f, struct image *img)
   init_color_table ();
 
 #ifndef USE_CAIRO
-  unsigned long bgcolor;
+  unsigned long bgcolor UNINIT;
   if (STRINGP (specified_bg))
     bgcolor = x_alloc_image_color (f, img, specified_bg,
 				   FRAME_BACKGROUND_PIXEL (f));
@@ -8542,13 +8552,19 @@ imagemagick_load_image (struct frame *f, struct image *img,
   char hint_buffer[MaxTextExtent];
   char *filename_hint = NULL;
 
+  /* Initialize the ImageMagick environment.  */
+  static bool imagemagick_initialized;
+  if (!imagemagick_initialized)
+    {
+      imagemagick_initialized = true;
+      MagickWandGenesis ();
+    }
+
   /* Handle image index for image types who can contain more than one image.
      Interface :index is same as for GIF.  First we "ping" the image to see how
      many sub-images it contains.  Pinging is faster than loading the image to
      find out things about it.  */
 
-  /* Initialize the imagemagick environment.  */
-  MagickWandGenesis ();
   image = image_spec_value (img->spec, QCindex, NULL);
   ino = INTEGERP (image) ? XFASTINT (image) : 0;
   image_wand = NewMagickWand ();
@@ -8849,8 +8865,10 @@ imagemagick_load_image (struct frame *f, struct image *img,
   DestroyMagickWand (image_wand);
   if (bg_wand) DestroyPixelWand (bg_wand);
 
-  /* `MagickWandTerminus' terminates the imagemagick environment.  */
-  MagickWandTerminus ();
+  /* Do not call MagickWandTerminus, to work around ImageMagick bug 825.  See:
+     https://github.com/ImageMagick/ImageMagick/issues/825
+     Although this bug was introduced in ImageMagick 6.9.9-14 and
+     fixed in 6.9.9-18, it's simpler to work around it in all versions.  */
 
   return 1;
 
@@ -8858,7 +8876,6 @@ imagemagick_load_image (struct frame *f, struct image *img,
   DestroyMagickWand (image_wand);
   if (bg_wand) DestroyPixelWand (bg_wand);
 
-  MagickWandTerminus ();
   /* TODO more cleanup.  */
   image_error ("Error parsing IMAGEMAGICK image `%s'", img->spec);
   return 0;