diff options
| -rw-r--r-- | src/mq/mq_notify.c | 67 |
1 files changed, 65 insertions, 2 deletions
diff --git a/src/mq/mq_notify.c b/src/mq/mq_notify.c index d85db1da..60bb2db2 100644 --- a/src/mq/mq_notify.c +++ b/src/mq/mq_notify.c @@ -1,10 +1,73 @@ #include <mqueue.h> #include <pthread.h> #include <errno.h> +#include <sys/socket.h> +#include <signal.h> +#include <unistd.h> #include "syscall.h" +struct args { + pthread_barrier_t barrier; + int sock; + const struct sigevent *sev; +}; + +void *start(void *p) +{ + struct args *args = p; + char buf[32]; + ssize_t n; + int s = args->sock; + void (*func)(union sigval) = args->sev->sigev_notify_function; + union sigval val = args->sev->sigev_value; + + pthread_barrier_wait(&args->barrier); + n = recv(s, buf, sizeof(buf), MSG_NOSIGNAL|MSG_WAITALL); + close(s); + if (n==sizeof buf && buf[sizeof buf - 1] == 1) + func(val); + return 0; +} + int mq_notify(mqd_t mqd, const struct sigevent *sev) { - errno = ENOSYS; - return -1; + struct args args = { .sev = sev }; + pthread_attr_t attr; + pthread_t td; + int s; + struct sigevent sev2; + static const char zeros[32]; + + if (!sev || sev->sigev_notify != SIGEV_THREAD) + return syscall(SYS_mq_notify, mqd, sev); + + s = socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, 0); + if (s < 0) return -1; + args.sock = s; + + if (sev->sigev_notify_attributes) attr = *sev->sigev_notify_attributes; + else pthread_attr_init(&attr); + pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); + pthread_barrier_init(&args.barrier, 0, 2); + + if (pthread_create(&td, &attr, start, &args)) { + __syscall(SYS_close, s); + errno = EAGAIN; + return -1; + } + + pthread_barrier_wait(&args.barrier); + pthread_barrier_destroy(&args.barrier); + + sev2.sigev_notify = SIGEV_THREAD; + sev2.sigev_signo = s; + sev2.sigev_value.sival_ptr = &zeros; + + if (syscall(SYS_mq_notify, mqd, &sev2) < 0) { + pthread_cancel(td); + __syscall(SYS_close, s); + return -1; + } + + return 0; } |