Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX
From: Erik Faye-Lund <hidden>
Date: 2016-06-15 22:59:17
Possibly related (same subject, not in this thread)
- 2016-06-15 · Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX · Filipe Cabecinhas <hidden>
- 2016-06-15 · Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX · Junio C Hamano <hidden>
- 2016-06-15 · Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX · Junio C Hamano <hidden>
- 2016-06-15 · Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX · Filipe Cabecinhas <hidden>
- 2016-06-15 · Re: write() _will_ fail on Mac OS X/XNU if nbytes > INT_MAX · Junio C Hamano <hidden>
I know I'm extremely late to the party, and this patch has already landed, but... On Sat, May 11, 2013 at 1:05 AM, Junio C Hamano [off-list ref] wrote:
Filipe Cabecinhas [off-list ref] writes:quoted
Due to a bug in the Darwin kernel, write() calls have a maximum size of INT_MAX bytes. This patch introduces a new compat function: clipped_write This function behaves the same as write() but will write, at most, INT_MAX characters. It may be necessary to include this function on Windows, too.
We are already doing something similar for Windows in mingw_write (see compat/mingw.c), but with a much smaller size. It feels a bit pointless to duplicate this logic.
quoted hunk ↗ jump to hunk
diff --git a/compat/clipped-write.c b/compat/clipped-write.c new file mode 100644 index 0000000..9183698 --- /dev/null +++ b/compat/clipped-write.c@@ -0,0 +1,13 @@ +#include <limits.h> +#include <unistd.h> + +/* + * Version of write that will write at most INT_MAX bytes. + * Workaround a xnu bug on Mac OS X + */ +ssize_t clipped_write(int fildes, const void *buf, size_t nbyte) +{ + if (nbyte > INT_MAX) + nbyte = INT_MAX; + return write(fildes, buf, nbyte); +}
If we were to reuse this logic with Windows, we'd need to have some way of overriding the max-size of the write.