osdep: Fix runtime failure on older Linux kernels

If QEMU finds newer kernel header files on compilation time, it will use
advertised features like pipe2 or SOCK_CLOEXEC by just doing a compile test.
If later the executables are executed on an older kernel (<2.6.27,
like Xen Dom0 2.6.18), then QEMU will fail on opening sockets and creating
pipes and returns the rather unspecific "qemu_init_main_loop failed".
This patch fixes this by checking the return values of these calls
for EINVAL and ENOSYS and falling back to the older versions automatically.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This commit is contained in:
Andre Przywara 2009-12-18 10:45:07 +01:00 committed by Aurelien Jarno
parent c1bb0dcef2
commit 3a03bfa5a2

18
osdep.c
View file

@ -262,13 +262,15 @@ int qemu_pipe(int pipefd[2])
#ifdef CONFIG_PIPE2
ret = pipe2(pipefd, O_CLOEXEC);
#else
if (ret != -1 || errno != ENOSYS) {
return ret;
}
#endif
ret = pipe(pipefd);
if (ret == 0) {
qemu_set_cloexec(pipefd[0]);
qemu_set_cloexec(pipefd[1]);
}
#endif
return ret;
}
@ -283,12 +285,14 @@ int qemu_socket(int domain, int type, int protocol)
#ifdef SOCK_CLOEXEC
ret = socket(domain, type | SOCK_CLOEXEC, protocol);
#else
if (ret != -1 || errno != EINVAL) {
return ret;
}
#endif
ret = socket(domain, type, protocol);
if (ret >= 0) {
qemu_set_cloexec(ret);
}
#endif
return ret;
}
@ -302,12 +306,14 @@ int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
#ifdef CONFIG_ACCEPT4
ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
#else
if (ret != -1 || errno != EINVAL) {
return ret;
}
#endif
ret = accept(s, addr, addrlen);
if (ret >= 0) {
qemu_set_cloexec(ret);
}
#endif
return ret;
}