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#include "../libfilezilla/buffer.hpp"
#include "../libfilezilla/glue/unix.hpp"
#include "../libfilezilla/process.hpp"
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
namespace fz {
bool set_cloexec(int fd)
{
#ifdef FD_CLOEXEC
if (fd != -1) {
int flags = fcntl(fd, F_GETFD);
if (flags >= 0) {
return fcntl(fd, F_SETFD, flags | FD_CLOEXEC) >= 0;
}
}
#else
errno = ENOSYS;
#endif
return false;
}
bool create_pipe(int fds[2])
{
disable_sigpipe();
fds[0] = -1;
fds[1] = -1;
#if HAVE_PIPE2
int res = pipe2(fds, O_CLOEXEC);
if (!res) {
return true;
}
else if (errno != ENOSYS) {
return false;
}
else
#endif
{
forkblock b;
if (pipe(fds) != 0) {
return false;
}
set_cloexec(fds[0]);
set_cloexec(fds[1]);
}
return true;
}
void disable_sigpipe()
{
[[maybe_unused]] static bool const once = []() { signal(SIGPIPE, SIG_IGN); return true; }();
}
bool create_socketpair(int fds[2])
{
disable_sigpipe();
int flags = SOCK_STREAM;
#ifdef SOCK_CLOEXEC
flags |= SOCK_CLOEXEC;
#else
forkblock b;
#endif
bool ret = socketpair(AF_UNIX, flags, 0, fds) == 0;
if (!ret) {
fds[0] = -1;
fds[1] = -1;
}
#ifndef SOCK_CLOEXEC
if (ret) {
set_cloexec(fds[0]);
set_cloexec(fds[1]);
}
#endif
return ret;
}
int send_fd(int socket, fz::buffer & buf, int fd, int & error)
{
if (buf.empty()) {
error = EINVAL;
return -1;
}
if (socket < 0) {
error = EBADF;
return -1;
}
#ifdef MSG_NOSIGNAL
const int flags = MSG_NOSIGNAL;
#else
const int flags = 0;
#endif
struct msghdr msg{};
struct iovec iov{};
iov.iov_base = buf.get();
iov.iov_len = buf.size();
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
union {
char buf[CMSG_SPACE(sizeof(int))];
struct cmsghdr header;
} cmsg_u; // For alignment reasons
if (fd != -1) {
msg.msg_control = cmsg_u.buf;
msg.msg_controllen = sizeof(cmsg_u.buf);
memset(msg.msg_control, 0, msg.msg_controllen);
struct cmsghdr * cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
}
int res{};
do {
res = sendmsg(socket, &msg, flags);
}
while (res == -1 && errno == EINTR);
if (res > 0) {
buf.consume(res);
error = 0;
}
else {
error = errno;
}
return res;
}
int read_fd(int socket, fz::buffer & buf, int & fd, int & error)
{
fd = -1;
if (socket < 0) {
error = EBADF;
return -1;
}
int flags{};
#ifdef MSG_NOSIGNAL
flags |= MSG_NOSIGNAL;
#endif
#ifdef MSG_CMSG_CLOEXEC
flags |= MSG_CMSG_CLOEXEC;
#else
forkblock b;
#endif
struct msghdr msg{};
struct iovec iov{};
iov.iov_base = buf.get(16*1024);
iov.iov_len = 16*1024;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
union {
char buf[CMSG_SPACE(sizeof(int))];
struct cmsghdr header;
} cmsg_u; // For alignment reasons
msg.msg_control = cmsg_u.buf;
msg.msg_controllen = sizeof(cmsg_u.buf);
int res{};
do {
res = recvmsg(socket, &msg, flags);
}
while (res == -1 && errno == EINTR);
error = errno;
if (res >= 0) {
buf.add(res);
error = 0;
struct cmsghdr * cmsg = CMSG_FIRSTHDR(&msg);
if (cmsg && cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS && cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
memcpy(&fd, CMSG_DATA(cmsg), sizeof(int));
#ifndef MSG_CMSG_CLOEXEC
set_cloexec(fd);
#endif
};
}
else {
error = errno;
}
return res;
}
int set_nonblocking(int fd, bool non_blocking)
{
int flags = fcntl(fd, F_GETFL);
if (flags == -1) {
return errno;
}
if (non_blocking) {
flags |= O_NONBLOCK;
}
else {
flags &= ~O_NONBLOCK;
}
int res = fcntl(fd, F_SETFL, flags);
if (res == -1) {
return errno;
}
return 0;
}
}
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