#include "image.h"

int
Hfmt(Fmt *f)
{
	ImgHdr h;
	char chan[12], *c;

	h = va_arg(f->args, ImgHdr);
	if((c = chantostr(chan, h.chan)) == nil)
		c = "error";
	return fmtprint(f, "%s%11s %11d %11d %11d %11d ",
		h.compressed ? "compressed\n" : "",
		c, h.r.min.x, h.r.min.y, h.r.max.x, h.r.max.y );
}

int
readimghdr(int fd, ImgHdr *hdr)
{
	char b[5*12];
	int n, m;

	if((n = readn(fd, b, 11)) != 11) {
		if(n >= 0)
			werrstr("short read");
		return -1;
	}

	if(hdr->compressed = memcmp(b, "compressed\n", 11) == 0)
		m = readn(fd, b, sizeof b);
	else
		m = readn(fd, b+11, sizeof(b)-11);

	if(m < 0)
		return -1;
	if((n += m) < sizeof b) {
		werrstr("short read");
		return -1;
	}

	/* don't allow atoi to read beyond the end of the buffer */
	if(b[5*12 - 1] != ' ') {
		werrstr("invalid");
		return -1;
	}

	if((hdr->chan = strtochan(b)) == 0) {
		werrstr("bad chan: %.11s", b);
		return -1;
	}
	hdr->r = Rect(atoi(b + 1*12), atoi(b + 2*12), atoi(b + 3*12), atoi(b + 4*12));

	return 0;
}