From: Marc-André Lureau <marcandre.lur...@redhat.com> Fortunately, qemu_fork() is no longer used since commit a95570e3e4d6 ("io/command: use glib GSpawn, instead of open-coding fork/exec"). (GSpawn uses posix_spawn() whenever possible instead)
Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> Reviewed-by: Daniel P. Berrangé <berra...@redhat.com> Message-Id: <20230221124802.4103554-2-marcandre.lur...@redhat.com> --- include/qemu/osdep.h | 14 --------- util/oslib-posix.c | 70 -------------------------------------------- util/oslib-win32.c | 9 ------ 3 files changed, 93 deletions(-) diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index 88c9facbf2..f68b5d8708 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -665,20 +665,6 @@ void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, */ char *qemu_get_pid_name(pid_t pid); -/** - * qemu_fork: - * - * A version of fork that avoids signal handler race - * conditions that can lead to child process getting - * signals that are otherwise only expected by the - * parent. It also resets all signal handlers to the - * default settings. - * - * Returns 0 to child process, pid number to parent - * or -1 on failure. - */ -pid_t qemu_fork(Error **errp); - /* Using intptr_t ensures that qemu_*_page_mask is sign-extended even * when intptr_t is 32-bit and we are aligning a long long. */ diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 77d882e681..760390b31e 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -583,76 +583,6 @@ char *qemu_get_pid_name(pid_t pid) } -pid_t qemu_fork(Error **errp) -{ - sigset_t oldmask, newmask; - struct sigaction sig_action; - int saved_errno; - pid_t pid; - - /* - * Need to block signals now, so that child process can safely - * kill off caller's signal handlers without a race. - */ - sigfillset(&newmask); - if (pthread_sigmask(SIG_SETMASK, &newmask, &oldmask) != 0) { - error_setg_errno(errp, errno, - "cannot block signals"); - return -1; - } - - pid = fork(); - saved_errno = errno; - - if (pid < 0) { - /* attempt to restore signal mask, but ignore failure, to - * avoid obscuring the fork failure */ - (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL); - error_setg_errno(errp, saved_errno, - "cannot fork child process"); - errno = saved_errno; - return -1; - } else if (pid) { - /* parent process */ - - /* Restore our original signal mask now that the child is - * safely running. Only documented failures are EFAULT (not - * possible, since we are using just-grabbed mask) or EINVAL - * (not possible, since we are using correct arguments). */ - (void)pthread_sigmask(SIG_SETMASK, &oldmask, NULL); - } else { - /* child process */ - size_t i; - - /* Clear out all signal handlers from parent so nothing - * unexpected can happen in our child once we unblock - * signals */ - sig_action.sa_handler = SIG_DFL; - sig_action.sa_flags = 0; - sigemptyset(&sig_action.sa_mask); - - for (i = 1; i < NSIG; i++) { - /* Only possible errors are EFAULT or EINVAL The former - * won't happen, the latter we expect, so no need to check - * return value */ - (void)sigaction(i, &sig_action, NULL); - } - - /* Unmask all signals in child, since we've no idea what the - * caller's done with their signal mask and don't want to - * propagate that to children */ - sigemptyset(&newmask); - if (pthread_sigmask(SIG_SETMASK, &newmask, NULL) != 0) { - Error *local_err = NULL; - error_setg_errno(&local_err, errno, - "cannot unblock signals"); - error_report_err(local_err); - _exit(1); - } - } - return pid; -} - void *qemu_alloc_stack(size_t *sz) { void *ptr, *guardpage; diff --git a/util/oslib-win32.c b/util/oslib-win32.c index 07ade41800..528c9ee156 100644 --- a/util/oslib-win32.c +++ b/util/oslib-win32.c @@ -283,15 +283,6 @@ char *qemu_get_pid_name(pid_t pid) } -pid_t qemu_fork(Error **errp) -{ - errno = ENOSYS; - error_setg_errno(errp, errno, - "cannot fork child process"); - return -1; -} - - #undef connect int qemu_connect_wrap(int sockfd, const struct sockaddr *addr, socklen_t addrlen) -- 2.39.2