[m-rev.] diff: Fix broken output in mandelbrot benchmark

[Paul Bone]

Fix broken output in mandelbrot benchmark

This benchmark broke when unicode support was introduced.  It was fixed
once, but somehow seems to have reverted to its broken version (maybe when
we imported from CVS?).

benchmarks/progs/mandelbrot/mandelbrot.m:
    Re-fix the benchmark.
---
 benchmarks/progs/mandelbrot/mandelbrot.m | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/benchmarks/progs/mandelbrot/mandelbrot.m b/benchmarks/progs/mandelbrot/mandelbrot.m
index c0c26ea..9d6c095 100644
--- a/benchmarks/progs/mandelbrot/mandelbrot.m
+++ b/benchmarks/progs/mandelbrot/mandelbrot.m
@@ -315,23 +315,27 @@ my_map(M, [X | Xs], [Y | Ys]) :-
 :- pred write_ppm(image::in, io::di, io::uo) is det.
 
 write_ppm(image(Width, Height, Rows), !IO) :-
-    io.open_output(filename, Result, !IO),
+    io.open_binary_output(filename, Result, !IO),
     (
         Result = ok(Stream),
-        io.format(Stream, "P6 %d %d 255\n", [i(Width), i(Height)], !IO),
+        format("P6 %d %d 255\n", [i(Width), i(Height)], Header),
+        foldl((pred(C::in, IO0::di, IO::uo) is det :-
+                write_byte(Stream, char.to_int(C), IO0, IO)
+            ), Header, !IO),
         foldl_pred(write_colour(Stream), Rows, !IO),
-        io.close_output(Stream, !IO)
+        io.close_binary_output(Stream, !IO)
     ;
         Result = error(Error),
         error(format("%s: %s", [s(filename), s(error_message(Error))]))
     ).
 
-:- pred write_colour(output_stream::in, colour::in, io::di, io::uo) is det.
+:- pred write_colour(binary_output_stream::in, colour::in, io::di, io::uo)
+    is det.
 
 write_colour(Stream, colour(R, G, B), !IO) :-
-    write_char(Stream, char.det_from_int(R), !IO),
-    write_char(Stream, char.det_from_int(G), !IO),
-    write_char(Stream, char.det_from_int(B), !IO).
+    write_byte(Stream, R, !IO),
+    write_byte(Stream, G, !IO),
+    write_byte(Stream, B, !IO).
 
 %----------------------------------------------------------------------------%
 
-- 
1.8.1.3