wayland/tests/os-wrappers-test.c
Kristian Høgsberg 53d24713a3 Change filedescriptor API to be thread safe
The update callback for the file descriptors was always a bit awkward and
un-intuitive.  The idea was that whenever the protocol code needed to
write data to the fd it would call the 'update' function.  This function
would adjust the mainloop so that it polls for POLLOUT on the fd so we
can eventually flush the data to the socket.

The problem is that in multi-threaded applications, any thread can issue
a request, which writes data to the output buffer and thus triggers the
update callback.  Thus, we'll be calling out with the display mutex
held and may call from any thread.

The solution is to eliminate the udpate callback and just require that
the application or server flushes all connection buffers before blocking.
This turns out to be a simpler API, although we now require clients to
deal with EAGAIN and non-blocking writes.  It also saves a few syscalls,
since the socket will be writable most of the time and most writes will
complete, so we avoid changing epoll to poll for POLLOUT, then write and
then change it back for each write.
2012-10-10 20:59:00 -04:00

365 lines
8.2 KiB
C

/*
* Copyright © 2012 Collabora, Ltd.
* Copyright © 2012 Intel Corporation
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting documentation, and
* that the name of the copyright holders not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no representations
* about the suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <unistd.h>
#include <dlfcn.h>
#include <errno.h>
#include <stdarg.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/epoll.h>
#include "wayland-private.h"
#include "test-runner.h"
#include "wayland-os.h"
static int fall_back;
static int (*real_socket)(int, int, int);
static int wrapped_calls_socket;
static int (*real_fcntl)(int, int, ...);
static int wrapped_calls_fcntl;
static ssize_t (*real_recvmsg)(int, struct msghdr *, int);
static int wrapped_calls_recvmsg;
static int (*real_epoll_create1)(int);
static int wrapped_calls_epoll_create1;
static void
init_fallbacks(int do_fallbacks)
{
fall_back = do_fallbacks;
real_socket = dlsym(RTLD_NEXT, "socket");
real_fcntl = dlsym(RTLD_NEXT, "fcntl");
real_recvmsg = dlsym(RTLD_NEXT, "recvmsg");
real_epoll_create1 = dlsym(RTLD_NEXT, "epoll_create1");
}
__attribute__ ((visibility("default"))) int
socket(int domain, int type, int protocol)
{
wrapped_calls_socket++;
if (fall_back && (type & SOCK_CLOEXEC)) {
errno = EINVAL;
return -1;
}
return real_socket(domain, type, protocol);
}
__attribute__ ((visibility("default"))) int
fcntl(int fd, int cmd, ...)
{
va_list ap;
void *arg;
wrapped_calls_fcntl++;
if (fall_back && (cmd == F_DUPFD_CLOEXEC)) {
errno = EINVAL;
return -1;
}
va_start(ap, cmd);
arg = va_arg(ap, void*);
va_end(ap);
return real_fcntl(fd, cmd, arg);
}
__attribute__ ((visibility("default"))) ssize_t
recvmsg(int sockfd, struct msghdr *msg, int flags)
{
wrapped_calls_recvmsg++;
if (fall_back && (flags & MSG_CMSG_CLOEXEC)) {
errno = EINVAL;
return -1;
}
return real_recvmsg(sockfd, msg, flags);
}
__attribute__ ((visibility("default"))) int
epoll_create1(int flags)
{
wrapped_calls_epoll_create1++;
if (fall_back) {
wrapped_calls_epoll_create1++; /* epoll_create() not wrapped */
errno = EINVAL;
return -1;
}
return real_epoll_create1(flags);
}
static void
do_os_wrappers_socket_cloexec(int n)
{
int fd;
int nr_fds;
nr_fds = count_open_fds();
/* simply create a socket that closes on exec */
fd = wl_os_socket_cloexec(PF_LOCAL, SOCK_STREAM, 0);
assert(fd >= 0);
/*
* Must have 2 calls if falling back, but must also allow
* falling back without a forced fallback.
*/
assert(wrapped_calls_socket > n);
exec_fd_leak_check(nr_fds);
}
TEST(os_wrappers_socket_cloexec)
{
/* normal case */
init_fallbacks(0);
do_os_wrappers_socket_cloexec(0);
}
TEST(os_wrappers_socket_cloexec_fallback)
{
/* forced fallback */
init_fallbacks(1);
do_os_wrappers_socket_cloexec(1);
}
static void
do_os_wrappers_dupfd_cloexec(int n)
{
int base_fd;
int fd;
int nr_fds;
nr_fds = count_open_fds();
base_fd = socket(PF_LOCAL, SOCK_STREAM, 0);
assert(base_fd >= 0);
fd = wl_os_dupfd_cloexec(base_fd, 13);
assert(fd >= 13);
close(base_fd);
/*
* Must have 4 calls if falling back, but must also allow
* falling back without a forced fallback.
*/
assert(wrapped_calls_fcntl > n);
exec_fd_leak_check(nr_fds);
}
TEST(os_wrappers_dupfd_cloexec)
{
init_fallbacks(0);
do_os_wrappers_dupfd_cloexec(0);
}
TEST(os_wrappers_dupfd_cloexec_fallback)
{
init_fallbacks(1);
do_os_wrappers_dupfd_cloexec(3);
}
struct marshal_data {
struct wl_connection *read_connection;
struct wl_connection *write_connection;
int s[2];
uint32_t read_mask;
uint32_t write_mask;
union {
int h[3];
} value;
int nr_fds_begin;
int nr_fds_conn;
int wrapped_calls;
};
static void
setup_marshal_data(struct marshal_data *data)
{
assert(socketpair(AF_UNIX,
SOCK_STREAM | SOCK_CLOEXEC, 0, data->s) == 0);
data->read_connection = wl_connection_create(data->s[0]);
assert(data->read_connection);
data->write_connection = wl_connection_create(data->s[1]);
assert(data->write_connection);
}
static void
marshal_demarshal(struct marshal_data *data,
void (*func)(void), int size, const char *format, ...)
{
struct wl_closure *closure;
static const int opcode = 4444;
static struct wl_object sender = { NULL, NULL, 1234 };
struct wl_message message = { "test", format, NULL };
struct wl_map objects;
struct wl_object object;
va_list ap;
uint32_t msg[1] = { 1234 };
va_start(ap, format);
closure = wl_closure_vmarshal(&sender, opcode, ap, &message);
va_end(ap);
assert(closure);
assert(wl_closure_send(closure, data->write_connection) == 0);
wl_closure_destroy(closure);
assert(wl_connection_flush(data->write_connection) == size);
assert(wl_connection_read(data->read_connection) == size);
wl_map_init(&objects);
object.id = msg[0];
closure = wl_connection_demarshal(data->read_connection,
size, &objects, &message);
wl_closure_invoke(closure, &object, func, data);
wl_closure_destroy(closure);
}
static void
validate_recvmsg_h(struct marshal_data *data,
struct wl_object *object, int fd1, int fd2, int fd3)
{
struct stat buf1, buf2;
assert(fd1 >= 0);
assert(fd2 >= 0);
assert(fd3 >= 0);
assert(fd1 != data->value.h[0]);
assert(fd2 != data->value.h[1]);
assert(fd3 != data->value.h[2]);
assert(fstat(fd3, &buf1) == 0);
assert(fstat(data->value.h[2], &buf2) == 0);
assert(buf1.st_dev == buf2.st_dev);
assert(buf1.st_ino == buf2.st_ino);
/* close the original file descriptors */
close(data->value.h[0]);
close(data->value.h[1]);
close(data->value.h[2]);
/* the dup'd (received) fds should still be open */
assert(count_open_fds() == data->nr_fds_conn + 3);
/*
* Must have 2 calls if falling back, but must also allow
* falling back without a forced fallback.
*/
assert(wrapped_calls_recvmsg > data->wrapped_calls);
if (data->wrapped_calls == 0 && wrapped_calls_recvmsg > 1)
printf("recvmsg fell back unforced.\n");
/* all fds opened during the test in any way should be gone on exec */
exec_fd_leak_check(data->nr_fds_begin);
}
static void
do_os_wrappers_recvmsg_cloexec(int n)
{
struct marshal_data data;
data.nr_fds_begin = count_open_fds();
data.wrapped_calls = n;
setup_marshal_data(&data);
data.nr_fds_conn = count_open_fds();
assert(pipe(data.value.h) >= 0);
data.value.h[2] = open("/dev/zero", O_RDONLY);
assert(data.value.h[2] >= 0);
marshal_demarshal(&data, (void *) validate_recvmsg_h,
8, "hhh", data.value.h[0], data.value.h[1],
data.value.h[2]);
}
TEST(os_wrappers_recvmsg_cloexec)
{
init_fallbacks(0);
do_os_wrappers_recvmsg_cloexec(0);
}
TEST(os_wrappers_recvmsg_cloexec_fallback)
{
init_fallbacks(1);
do_os_wrappers_recvmsg_cloexec(1);
}
static void
do_os_wrappers_epoll_create_cloexec(int n)
{
int fd;
int nr_fds;
nr_fds = count_open_fds();
fd = wl_os_epoll_create_cloexec();
assert(fd >= 0);
#ifdef EPOLL_CLOEXEC
assert(wrapped_calls_epoll_create1 == n);
#else
printf("No epoll_create1.\n");
#endif
exec_fd_leak_check(nr_fds);
}
TEST(os_wrappers_epoll_create_cloexec)
{
init_fallbacks(0);
do_os_wrappers_epoll_create_cloexec(1);
}
TEST(os_wrappers_epoll_create_cloexec_fallback)
{
init_fallbacks(1);
do_os_wrappers_epoll_create_cloexec(2);
}
/* FIXME: add tests for wl_os_accept_cloexec() */