Many small edits.

src/cmd/draw/iconv.c

@@ -0,0 +1,102 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <memdraw.h>
+
+void
+usage(void)
+{
+	fprint(2, "usage: iconv [-u] [-c chanstr] [file]\n");
+	exits("usage");
+}
+
+void
+writeuncompressed(int fd, Memimage *m)
+{
+	char chanstr[32];
+	int bpl, y, j;
+	uchar *buf;
+
+	if(chantostr(chanstr, m->chan) == nil)
+		sysfatal("can't convert channel descriptor: %r");
+	fprint(fd, "%11s %11d %11d %11d %11d ",
+		chanstr, m->r.min.x, m->r.min.y, m->r.max.x, m->r.max.y);
+
+	bpl = bytesperline(m->r, m->depth);
+	buf = malloc(bpl);
+	if(buf == nil)
+		sysfatal("malloc failed: %r");
+	for(y=m->r.min.y; y<m->r.max.y; y++){
+		j = unloadmemimage(m, Rect(m->r.min.x, y, m->r.max.x, y+1), buf, bpl);
+		if(j != bpl)
+			sysfatal("image unload failed: %r");
+		if(write(fd, buf, bpl) != bpl)
+			sysfatal("write failed: %r");
+	}
+	free(buf);
+}
+
+void
+main(int argc, char *argv[])
+{
+	char *tostr, *file;
+	int fd, uncompressed;
+	ulong tochan;
+	Memimage *m, *n;
+
+	tostr = nil;
+	uncompressed = 0;
+	ARGBEGIN{
+	case 'c':
+		tostr = EARGF(usage());
+		break;
+	case 'u':
+		uncompressed = 1;
+		break;
+	default:
+		usage();
+	}ARGEND
+
+	memimageinit();
+
+	file = "<stdin>";
+	m = nil;
+
+	switch(argc){
+	case 0:
+		m = readmemimage(0);
+		break;
+	case 1:
+		file = argv[0];
+		fd = open(file, OREAD);
+		if(fd < 0)
+			sysfatal("can't open %s: %r", file);
+		m = readmemimage(fd);
+		close(fd);
+		break;
+	default:
+		usage();
+	}
+
+	if(m == nil)
+		sysfatal("can't read %s: %r", file);
+
+	if(tostr == nil)
+		tochan = m->chan;
+	else{
+		tochan = strtochan(tostr);
+		if(tochan == 0)
+			sysfatal("bad channel descriptor '%s'", tostr);
+	}
+
+	n = allocmemimage(m->r, tochan);
+	if(n == nil)
+		sysfatal("can't allocate new image: %r");
+
+	memimagedraw(n, n->r, m, m->r.min, nil, ZP, S);
+	if(uncompressed)
+		writeuncompressed(1, n);
+	else
+		writememimage(1, n);
+	exits(nil);
+}