make pa_exifautotran be more specific - only "skip" the known SOS error, and dont touch file if the output of the rotate is 0 bytes -- JUST IN CASE

utils/pa_exifautotran

@@ -18,7 +18,7 @@ EOF
     exit 0;;
   esac
 
-	case $(exiftool -t -s -s -s -n -IFD0:Orientation -IFD1:Orientation "$i") in
+	case $(jpegexiforient "$i") in
     1) transform="";;
     2) transform="-flip horizontal";;
     3) transform="-rotate 180";;
@@ -32,9 +32,20 @@ EOF
 
   if test -n "$transform"; then
     echo Executing: jpegtran -copy all $transform "$i" >&2
-    jpegtran -copy all $transform "$i" > tempfile
-    rm "$i"
-    mv tempfile "$i"
-    jpegexiforient -1 "$i"
+    jpegtran -copy all $transform "$i" > tempfile 2> err
+    ret=$?
+    err=`cat err`
+    if [ "$ret" = "2" ] && [ "$err" != "Invalid SOS parameters for sequential JPEG" ]; then
+        echo "$0: FAILED to rotate jpeg with unknown failure - dont change file"
+        rm err
+        rm tempfile
+        exit 1
+    fi
+    # last sanity check - make sure tempfile is not empty 
+    if [ -s tempfile ]; then
+        rm err
+        mv tempfile "$i"
+        jpegexiforient -1 "$i" > /dev/null
+    fi
   fi
 done