Attachment 628161 Details for Bug 859485 – Reproducer

Reproducer

foo.c (text/plain), 2.45 KB, created by Rui Matos on 2012-10-16 13:36:09 UTC

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Creator: Rui Matos

Created: 2012-10-16 13:36:09 UTC

Size: 2.45 KB

patch

obsolete

>#include <assert.h>
>#include <stdio.h>
>#include <unistd.h>
>#include <stdlib.h>
>#include <errno.h>
>#include <fcntl.h>
>#include <sys/ioctl.h>
>#include <linux/kd.h>
>
>#define USEC_PER_MSEC 1000ULL
>
>int close_nointr(int fd) {
>        assert(fd >= 0);
>
>        for (;;) {
>                int r;
>
>                r = close(fd);
>                if (r >= 0)
>                        return r;
>
>                if (errno != EINTR)
>                        return -errno;
>        }
>}
>
>void close_nointr_nofail(int fd) {
>        int saved_errno = errno;
>
>        /* like close_nointr() but cannot fail, and guarantees errno
>         * is unchanged */
>
>        close_nointr(fd) == 0;
>
>        errno = saved_errno;
>}
>
>int open_terminal(const char *name, int mode) {
>        int fd, r;
>        unsigned c = 0;
>
>        /*
>         * If a TTY is in the process of being closed opening it might
>         * cause EIO. This is horribly awful, but unlikely to be
>         * changed in the kernel. Hence we work around this problem by
>         * retrying a couple of times.
>         *
>         * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/554172/comments/245
>         */
>
>        for (;;) {
>                fd = open(name, mode);
>                if (fd >= 0)
>                        break;
>
>                if (errno != EIO)
>                        return -errno;
>
>                /* Max 1s in total */
>                if (c >= 20)
>                        return -errno;
>
>                usleep(50 * USEC_PER_MSEC);
>                c++;
>        }
>
>        if (fd < 0)
>                return -errno;
>
>        r = isatty(fd);
>        if (r < 0) {
>                close_nointr_nofail(fd);
>                return -errno;
>        }
>
>        if (!r) {
>                close_nointr_nofail(fd);
>                return -ENOTTY;
>        }
>
>        return fd;
>}
>
>int main(int argc, char **argv) {
>        const char *vc;
>        int fd = -1;
>        int r = EXIT_FAILURE;
>
>        if (argv[1])
>                vc = argv[1];
>        else
>                vc = "/dev/tty0";
>
>        fd = open_terminal(vc, O_RDWR|O_CLOEXEC);
>        if (fd < 0) {
>                printf("Failed to open %s\n", vc);
>                goto finish;
>        }
>
>        if (ioctl(fd, KDSKBMODE, K_UNICODE) < 0) {
>                printf("Error setting current keyboard mode: %s\n", strerror(errno));
>                goto finish;
>        }
>
>        r = EXIT_SUCCESS;
>finish:
>        if (fd >= 0)
>                close_nointr_nofail(fd);
>
>        return r;
>}

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Attachments on bug 859485: 615495 | 615496 | 628161