diff options
| -rw-r--r-- | source/fitz/draw-device.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/source/fitz/draw-device.c b/source/fitz/draw-device.c index 9146b3e2..60735460 100644 --- a/source/fitz/draw-device.c +++ b/source/fitz/draw-device.c @@ -220,7 +220,11 @@ static void fz_knockout_end(fz_draw_device *dev) else fz_blend_pixmap(state[0].dest, state[1].dest, 255, blendmode, isolated, state[1].shape); - fz_drop_pixmap(dev->ctx, state[1].dest); + /* The following test should not be required, but just occasionally + * errors can cause the stack to get out of sync, and this saves our + * bacon. */ + if (state[0].dest != state[1].dest) + fz_drop_pixmap(dev->ctx, state[1].dest); if (state[0].shape != state[1].shape) { if (state[0].shape) @@ -1352,8 +1356,13 @@ fz_draw_pop_clip(fz_device *devp) fz_paint_pixmap_with_mask(state[0].shape, state[1].shape, state[1].mask); fz_drop_pixmap(dev->ctx, state[1].shape); } - fz_drop_pixmap(dev->ctx, state[1].mask); - fz_drop_pixmap(dev->ctx, state[1].dest); + /* The following tests should not be required, but just occasionally + * errors can cause the stack to get out of sync, and this might save + * our bacon. */ + if (state[0].mask != state[1].mask) + fz_drop_pixmap(dev->ctx, state[1].mask); + if (state[0].dest != state[1].dest) + fz_drop_pixmap(dev->ctx, state[1].dest); #ifdef DUMP_GROUP_BLENDS fz_dump_blend(dev->ctx, state[0].dest, " to get "); if (state[0].shape) @@ -1579,7 +1588,11 @@ fz_draw_end_group(fz_device *devp) else fz_blend_pixmap(state[0].dest, state[1].dest, alpha * 255, blendmode, isolated, state[1].shape); - fz_drop_pixmap(dev->ctx, state[1].dest); + /* The following test should not be required, but just occasionally + * errors can cause the stack to get out of sync, and this might save + * our bacon. */ + if (state[0].dest != state[1].dest) + fz_drop_pixmap(dev->ctx, state[1].dest); if (state[0].shape != state[1].shape) { if (state[0].shape) @@ -1940,8 +1953,13 @@ fz_draw_end_tile(fz_device *devp) /* Do nothing */ } - fz_drop_pixmap(dev->ctx, state[1].dest); - fz_drop_pixmap(dev->ctx, state[1].shape); + /* The following tests should not be required, but just occasionally + * errors can cause the stack to get out of sync, and this might save + * our bacon. */ + if (state[0].dest != state[1].dest) + fz_drop_pixmap(dev->ctx, state[1].dest); + if (state[0].shape != state[1].shape) + fz_drop_pixmap(dev->ctx, state[1].shape); #ifdef DUMP_GROUP_BLENDS fz_dump_blend(dev->ctx, state[0].dest, " to get "); if (state[0].shape) |