/*
 * ================================
 * eli960@qq.com
 * http:/linuxmail.cn/
 * 2015年10月12日
 * ================================
 */

#include "zcc/zcc_stdlib.h"
#include "zcc/zcc_errno.h"
#ifdef _WIN64
#include <WinSock2.h>
#include <handleapi.h>
#include <io.h>
#else // _WIN64
#include <unistd.h>
#include <fcntl.h>
#include <sys/file.h>
#ifdef __linux__
#include <sys/ioctl.h>
#include <sys/socket.h>
#endif // __linux__
#include <poll.h>
#endif // _WIN64

zcc_namespace_begin;

#ifdef __linux__
/**
 * @brief 通过Unix域套接字发送文件描述符
 * @param fd 用于发送的套接字描述符
 * @param sendfd 要发送的文件描述符
 * @return 成功返回1,失败返回-1
 */
/* postfix src/util/unix_send_fd.c */
int send_fd(int fd, int sendfd)
{
 struct msghdr msg;
 struct iovec iov[1];

 union
 {
 struct cmsghdr just_for_alignment;
 char control[CMSG_SPACE(sizeof(sendfd))];
 } control_un;
 struct cmsghdr *cmptr;

 // 初始化消息头
 std::memset(&msg, 0, sizeof(msg));
 msg.msg_control = control_un.control;
 msg.msg_controllen = sizeof(control_un.control);

 cmptr = CMSG_FIRSTHDR(&msg);
 cmptr->cmsg_len = CMSG_LEN(sizeof(sendfd));
 cmptr->cmsg_level = SOL_SOCKET;
 cmptr->cmsg_type = SCM_RIGHTS;

 int *int_ptr = (int *)(CMSG_DATA(cmptr));
 *int_ptr = sendfd;

 msg.msg_name = 0;
 msg.msg_namelen = 0;

 iov->iov_base = var_blank_buffer;
 iov->iov_len = 1;
 msg.msg_iov = iov;
 msg.msg_iovlen = 1;

 int sendmsg_ret;
 do
 {
 // 调用sendmsg函数发送消息
 sendmsg_ret = (int)::sendmsg(fd, &msg, 0);
 } while ((sendmsg_ret < 0) && (errno == EINTR));
 if (sendmsg_ret >= 0)
 {
 return 1;
 }

 return (-1);
}

/**
 * @brief 通过Unix域套接字接收文件描述符
 * @param fd 用于接收的套接字描述符
 * @return 接收到的文件描述符,失败返回-1
 */
/* postfix src/util/unix_recv_fd.c */
int recv_fd(int fd)
{
 struct msghdr msg;
 int newfd;
 struct iovec iov[1];
 char buf[1];

 union
 {
 struct cmsghdr just_for_alignment;
 char control[CMSG_SPACE(sizeof(newfd))];
 } control_un;
 struct cmsghdr *cmptr;

 // 初始化消息头
 std::memset(&msg, 0, sizeof(msg));
 msg.msg_control = control_un.control;
 msg.msg_controllen = sizeof(control_un.control);

 msg.msg_name = 0;
 msg.msg_namelen = 0;

 iov->iov_base = buf;
 iov->iov_len = sizeof(buf);
 msg.msg_iov = iov;
 msg.msg_iovlen = 1;

 int recvmsg_ret;
 do
 {
 // 调用recvmsg函数接收消息
 recvmsg_ret = (int)::recvmsg(fd, &msg, 0);
 } while ((recvmsg_ret < 0) && (errno == EINTR));
 if (recvmsg_ret < 0)
 {
 return -1;
 }

 if (((cmptr = CMSG_FIRSTHDR(&msg)) != 0) && (cmptr->cmsg_len == CMSG_LEN(sizeof(newfd))))
 {
 if (cmptr->cmsg_level != SOL_SOCKET)
 {
 // 输出错误信息
 zcc_fatal("control level %d != SOL_SOCKET", cmptr->cmsg_level);
 }
 if (cmptr->cmsg_type != SCM_RIGHTS)
 {
 // 输出错误信息
 zcc_fatal("control type %d != SCM_RIGHTS", cmptr->cmsg_type);
 }
 int *int_ptr = (int *)(CMSG_DATA(cmptr));
 newfd = *int_ptr;
 return newfd;
 }

 return (-1);
}
#endif // __linux__

zcc_namespace_end;