Eric Blake <eblake@xxxxxxxxxx> writes: > On Sat, Feb 03, 2024 at 09:02:25AM +0100, Markus Armbruster wrote: >> The __linux__ version of qemu_chr_open_pp_fd() tries to claim the >> parport device with a PPCLAIM ioctl(). On success, it stores the file >> descriptor in the chardev object, and returns success. On failure, it >> closes the file descriptor, and returns failure. >> >> chardev_new() then passes the Chardev to object_unref(). This duly >> calls char_parallel_finalize(), which closes the file descriptor >> stored in the chardev object. Since qemu_chr_open_pp_fd() didn't >> store it, it's still zero, so this closes standard input. Ooopsie. >> >> To demonstate, add a unit test. With the bug above unfixed, running >> this test closes standard input. char_hotswap_test() happens to run >> next. It opens a socket, duly gets file descriptor 0, and since it >> tests for success with > 0 instead of >= 0, it fails. > > Two bugs for the price of one! > >> >> The test needs to be conditional exactly like the chardev it tests. >> Since the condition is rather complicated, steal the solution from the >> serial chardev: define HAVE_CHARDEV_PARALLEL in qemu/osdep.h. This >> also permits simplifying chardev/meson.build a bit. >> >> The bug fix is easy enough: store the file descriptor, and leave >> closing it to char_parallel_finalize(). >> >> Signed-off-by: Markus Armbruster <armbru@xxxxxxxxxx> >> --- > >> +++ b/include/qemu/osdep.h >> @@ -508,11 +508,18 @@ void qemu_anon_ram_free(void *ptr, size_t size); >> >> #ifdef _WIN32 >> #define HAVE_CHARDEV_SERIAL 1 >> -#elif defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ >> +#define HAVE_CHARDEV_PARALLEL 1 >> +#else >> +#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ >> || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \ >> || defined(__GLIBC__) || defined(__APPLE__) >> #define HAVE_CHARDEV_SERIAL 1 >> #endif >> +#if defined(__linux__) || defined(__FreeBSD__) \ >> + || defined(__FreeBSD_kernel__) || defined(__DragonFly__) >> +#define HAVE_CHARDEV_PARALLEL 1 >> +#endif >> +#endif > > Not for this patch, but I've grown to like a preprocessor style I've > seen in other projects to make it easier to read nested #if: > > #ifdef _WIN32 > # define HAVE_CHARDEV_SERIAL 1 > # define HAVE_CHARDEV_PARALLEL 1 > #else > # if defined(__linux__) ... defined(__APPLE__) > # define HAVE_CHARDEV_SERIAL 1 > # endif > # if defined(__linux__) ... defined(__DragonFly__) > # define HAVE_CHARDEV_PARALLEL 1 > # endif > #endif I like this style, too. >> +++ b/chardev/meson.build >> @@ -21,11 +21,9 @@ if host_os == 'windows' >> else >> chardev_ss.add(files( >> 'char-fd.c', >> + 'char-parallel.c', >> 'char-pty.c', > > Indentation looks off. Otherwise, Will fix. > Reviewed-by: Eric Blake <eblake@xxxxxxxxxx> Thanks! _______________________________________________ Devel mailing list -- devel@xxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxx
