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Message-ID: <253CC91A3D00087821A92B6D43237A44@eigenstate.org>
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Subject: Re: [9front] minor bug report: png spews
Date: Fri, 21 Aug 2020 11:47:26 -0700
From: ori@eigenstate.org
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X-Bullshit: engine dependency control 

> looks like it's just a forgotten debug print because it only occurs with -9. oddly, there are rather a lot of lines computing just for that message. 
> 
> here's a patch, tested minimally. let me know if you want a different format; this is diff -c.
> 
> png.c.0:132,138 - png.c:132,137
>   	Rawimage **array, *r, *c;
>   	Image *i, *i2;
>   	int j, ch, outchan;
> - 	long len;
>   	Biobuf b;
>   	char buf[32];
>   	static int inited;
> png.c.0:207,230 - png.c:206,211
>   	}
>   	if(nineflag){
>   		chantostr(buf, outchan);
> - 		len = (c->r.max.x - c->r.min.x) * (c->r.max.y - c->r.min.y);
> - 		switch(c->chandesc){
> - 		case CY:
> - 			// len *= 1;
> - 			break;
> - 		case CYA16:
> - 			len *= 2;
> - 			break;
> - 		case CRGB24:
> - 			len *= 3;
> - 			break;
> - 		case CRGBA32:
> - 			len *= 4;
> - 			break;
> - 		}
> - 		if(c->chanlen != len)
> - 			fprint(2, "%s: writing %d bytes for len %ld chan %s\n",
> - 				argv0, c->chanlen, len, buf);
>   		print("%11s %11d %11d %11d %11d ", buf,
>   			c->r.min.x, c->r.min.y, c->r.max.x, c->r.max.y);
>   		if(write(1, c->chans[0], c->chanlen) != c->chanlen){

Hm. Does this happen on all PNG images?
If not, do you have an example image that triggers it?

I haven't tested yet, but it looks like it's warning about
a possible miscomputation of image size.