WIP: Gracefully handle nothing to do

src/lib/OpenEXR/ImfDeepScanLineInputFile.cpp

@@ -931,6 +931,9 @@ void ScanLineProcess::run_fill (
     int fbY,
     const std::vector<DeepSlice> &filllist)
 {
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     for (auto& fills: filllist)
     {
         uint8_t*       ptr;
@@ -1011,6 +1014,9 @@ void ScanLineProcess::copy_sample_count (
 {
     const Slice& scslice = outfb->getSampleCountSlice ();
 
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     int     end = cinfo.height - decoder.user_line_end_ignore;
     int64_t xS = int64_t (scslice.xStride);
     int64_t yS = int64_t (scslice.yStride);

src/lib/OpenEXR/ImfDeepTiledInputFile.cpp

@@ -1141,6 +1141,9 @@ void TileProcess::run_fill (
     const DeepFrameBuffer *outfb, int fb_absX, int fb_absY, int t_absX, int t_absY,
     const std::vector<DeepSlice> &filllist)
 {
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     for (auto& fills: filllist)
     {
         uint8_t* ptr;
@@ -1227,6 +1230,9 @@ void TileProcess::copy_sample_count (
     if (s.xSampling != 1 || s.ySampling != 1)
         throw IEX_NAMESPACE::ArgExc ("Tiled data should not have subsampling.");
 
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     int xOffset = s.xTileCoords ? 0 : t_absX;
     int yOffset = s.yTileCoords ? 0 : t_absY;
 

src/lib/OpenEXR/ImfScanLineInputFile.cpp

@@ -660,6 +660,9 @@ void ScanLineProcess::run_fill (
     int fbY,
     const std::vector<Slice> &filllist)
 {
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     for (auto& s: filllist)
     {
         uint8_t*       ptr;

src/lib/OpenEXR/ImfTiledInputFile.cpp

@@ -988,6 +988,9 @@ void TileProcess::run_fill (
     const FrameBuffer *outfb, int fb_absX, int fb_absY, int t_absX, int t_absY,
     const std::vector<Slice> &filllist)
 {
+    if (cinfo.height == 0 || cinfo.width == 0)
+        return;
+
     for (auto& s: filllist)
     {
         uint8_t* ptr;

src/lib/OpenEXRCore/compression.c

@@ -509,7 +509,9 @@ exr_uncompress_chunk (exr_decode_pipeline_t* decode)
         if ((decode->decode_flags & EXR_DECODE_SAMPLE_DATA_ONLY)) return rv;
     }
 
-    if (rv == EXR_ERR_SUCCESS)
+    if (rv == EXR_ERR_SUCCESS &&
+        decode->chunk.packed_size > 0 &&
+        decode->chunk.unpacked_size > 0)
         rv = decompress_data (
             ctxt,
             part->comp_type,

src/lib/OpenEXRCore/decoding.c

@@ -154,8 +154,9 @@ default_read_chunk (exr_decode_pipeline_t* decode)
         decode->unpacked_alloc_size == 0)
         decode->unpacked_buffer = NULL;
 
-    if (part->storage_mode == EXR_STORAGE_DEEP_SCANLINE ||
-        part->storage_mode == EXR_STORAGE_DEEP_TILED)
+    if ((part->storage_mode == EXR_STORAGE_DEEP_SCANLINE ||
+         part->storage_mode == EXR_STORAGE_DEEP_TILED) &&
+        decode->chunk.sample_count_table_size > 0)
     {
         rv = internal_decode_alloc_buffer (
             decode,
@@ -192,7 +193,7 @@ default_read_chunk (exr_decode_pipeline_t* decode)
                 decode->packed_sample_count_table);
         }
     }
-    else
+    else if (decode->chunk.packed_size > 0)
     {
         rv = internal_decode_alloc_buffer (
             decode,
@@ -204,6 +205,8 @@ default_read_chunk (exr_decode_pipeline_t* decode)
         rv = exr_read_chunk (
             ctxt, decode->part_index, &(decode->chunk), decode->packed_buffer);
     }
+    else
+        rv = EXR_ERR_SUCCESS;
 
     return rv;
 }
@@ -310,6 +313,11 @@ exr_decoding_initialize (
         }
     }
 
+    // will have already been reported during header parse, but just
+    // stop the file from being read
+    if (!part->channels || part->channels->type != EXR_ATTR_CHLIST)
+        return EXR_ERR_INVALID_ATTR;
+
     rv = internal_coding_fill_channel_info (
         &(decode->channels),
         &(decode->channel_count),